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  • From Java Object class to C++

    - by Rui
    Hi, I'm relative new to C++ and my background is in Java. I have to port some code from Java to C++ and some doubts came up relative to the Object Java's class. So, if I want to port this: void Algorithm::setInputParameter(std::string name, Object object) { ..... } I believe I should use void* type or templates right? I don't know what's the "standard" procedure to accomplish it. Thanks

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  • Custom Cocoa Framework and a problem using it

    - by happyCoding25
    Hello, I made a custom cocoa framework just to experiment and find the best way to make one but ran in to a problem using it. The framework project builds and compiles just fine, but when I use it in an xcode project I get the error, 'LogTest' undeclared. The name of the framework is LogTest Heres the code to my app that uses the framework: AppDelegate.h: #import <Cocoa/Cocoa.h> #import <LogTest/LogTest.h> @interface TestAppDelegate : NSObject <NSApplicationDelegate> { NSWindow *window; } @property (assign) IBOutlet NSWindow *window; @end AppDelegate.m: #import "TestAppDelegate.h" @implementation TestAppDelegate @synthesize window; - (void)awakeFromNib { [LogTest logStart:@"testing 123":@"testing 1234"]; //This is the line where the error occurs } @end Framework Code........ LogTest.h: #import <Cocoa/Cocoa.h> #import "Method.h" @protocol LogTest //Not sure if this is needed I just wanted a blank header @end Method.h: #import <Cocoa/Cocoa.h> @interface Method : NSObject { } + (void)logStart:(NSString *)test:(NSString *)test2; @end Method.m: #import "Method.h" @implementation Method + (void)logStart:(NSString *)test:(NSString *)test2 { NSLog(test); NSLog(test2); } @end If anyone knows why I am getting this error please reply. Thanks for any help

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  • Cannot implicity convert type void to System.Threading.Tasks.Task<bool>

    - by sagesky36
    I have a WCF Service that contains the following method. All the methods in the service are asynchrounous and compile just fine. public async Task<Boolean> ValidateRegistrationAsync(String strUserName) { try { using (YeagerTechEntities DbContext = new YeagerTechEntities()) { DbContext.Configuration.ProxyCreationEnabled = false; DbContext.Database.Connection.Open(); var reg = await DbContext.aspnet_Users.FirstOrDefaultAsync(f => f.UserName == strUserName); if (reg != null) return true; else return false; } } catch (Exception) { throw; } } My client application was set to access the WCF service with the check box for the "Allow generation of asynchronous operations" and it generated the proxy just fine. I am receiving the above subject error when trying to call this WCF service method from my client with the following code. Mind you, I know what the error message means, but this is my first time trying to call an asynchronous task in a WCF service from a client. Task<Boolean> blnMbrShip = db.ValidateRegistrationAsync(FormsAuthentication.Decrypt(cn.Value).Name); What do I need to do to properly call the method so the design time compile error disappears? Thanks so much in advance...

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  • Equivalent to window.setTimeout() for C++

    - by bobobobo
    In javascript there's this sweet, sweet function window.setTimeout( func, 1000 ) ; which will asynchronously invoke func after 1000 ms. I want to do something similar in C++ (without multithreading), so I put together a sample loop like: #include <stdio.h> struct Callback { // The _time_ this function will be executed. double execTime ; // The function to execute after execTime has passed void* func ; } ; // Sample function to execute void go() { puts( "GO" ) ; } // Global program-wide sense of time double time ; int main() { // start the timer time = 0 ; // Make a sample callback Callback c1 ; c1.execTime = 10000 ; c1.func = go ; while( 1 ) { // its time to execute it if( time c1.execTime ) { c1.func ; // !! doesn't work! } time++; } } How can I make something like this work?

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  • IPhone sdk stop the accelerometer from working when something happens.

    - by Harry
    Hi, I am using the accelerometer to move a few UIImageViews around the screen, at the moment the accelerometer only works when a NSTimer is at 0, this is fine. I would also like to make the accelerometer stop again when a different function happens. here is my code at the moment: -(BOOL) accelerometerWorks { return time == 0; } -(void) accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration{ if(![self accelerometerWorks]) return; valueX = acceleration.x*25.5; int newX = (int)(ball.center.x +valueX); if (newX 320-BALL_RADIUS) newX = 320-BALL_RADIUS; if (newX < 0+BALL_RADIUS) newX = 0+BALL_RADIUS; int XA = (int)(balloonbit1.center.x +valueX); if (XA 320-BALL_RADIUS) XA = 320-BALL_RADIUS; if (XA < 0+BALL_RADIUS) XA = 0+BALL_RADIUS; int XB = (int)(balloonbit2.center.x +valueX); if (XB 320-BALL_RADIUS) XB = 320-BALL_RADIUS; if (XB < 0+BALL_RADIUS) XB = 0+BALL_RADIUS; int XI = (int)(balloonbit3.center.x +valueX); if (XI 320-BALL_RADIUS) XI = 320-BALL_RADIUS; if (XI < 0+BALL_RADIUS) XI = 0+BALL_RADIUS; int XJ = (int)(balloonbit4.center.x +valueX); if (XJ 320-BALL_RADIUS) XJ = 320-BALL_RADIUS; if (XJ < 0+BALL_RADIUS) XJ = 0+BALL_RADIUS; int XE = (int)(balloonbit5.center.x +valueX); if (XE 320-BALL_RADIUS) XE = 320-BALL_RADIUS; if (XE < 0+BALL_RADIUS) XE = 0+BALL_RADIUS; int XF = (int)(balloonbit6.center.x +valueX); if (XF 320-BALL_RADIUS) XF = 320-BALL_RADIUS; if (XF < 0+BALL_RADIUS) XF = 0+BALL_RADIUS; int XH = (int)(balloonbit8.center.x +valueX); if (XH 320-BALL_RADIUS) XH = 320-BALL_RADIUS; if (XH < 0+BALL_RADIUS) XH = 0+BALL_RADIUS; ball.center = CGPointMake (newX, 429); balloonbit1.center = CGPointMake (XA, 429); balloonbit2.center = CGPointMake (XB, 426); balloonbit3.center = CGPointMake (XI, 410); balloonbit4.center = CGPointMake (XJ, 415); balloonbit5.center = CGPointMake (XE, 409); balloonbit6.center = CGPointMake (XF, 427); balloonbit8.center = CGPointMake (XH, 417); } This all works fine, i would now like to stop the accelerometer from working, using the same accelerometerWorks method or a new method, accelerometerWontWork. This is the code that when it is called i would like the accelerometer to stop. (it is very long so i wont put all of it there, but its all the same throughout): -(void) checkCollision{ if (CGRectIntersectsRect(pinend.frame, balloonbit1.frame)){ if (balloonbit1.frame.origin.y pinend.frame.origin.y){ [maintimer invalidate]; levelfailed.center = CGPointMake (160, 235); } } if (CGRectIntersectsRect(pinend.frame, balloonbit2.frame)){ if (balloonbit2.frame.origin.y pinend.frame.origin.y){ [maintimer invalidate]; levelfailed.center = CGPointMake (160, 235); } } if (CGRectIntersectsRect(pinend.frame, balloonbit3.frame)){ if (balloonbit3.frame.origin.y pinend.frame.origin.y){ [maintimer invalidate]; levelfailed.center = CGPointMake (160, 235); } } } I understand that i may have to turn this into a BOOL. Thats fine. If i haven't explained it well please say and i will re write it. Thanks! Harry.

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  • question/problem regarding assigning an array of char *

    - by Fantastic Fourier
    Hi I'm working with C and I have a question about assigning pointers. struct foo { int _bar; char * _car[MAXINT]; // this is meant to be an array of char * so that it can hold pointers to names of cars } int foofunc (void * arg) { int bar; char * car[MAXINT]; struct foo thing = (struct foo *) arg; bar = arg->_bar; // this works fine car = arg->_car; // this gives compiler errors of incompatible types in assignment } car and _car have same declaration so why am I getting an error about incompatible types? My guess is that it has something to do with them being pointers (because they are pointers to arrays of char *, right?) but I don't see why that is a problem. when i declared char * car; instead of char * car[MAXINT]; it compiles fine. but I don't see how that would be useful to me later when I need to access certain info using index, it would be very annoying to access that info later. in fact, I'm not even sure if I am going about the right way, maybe there is a better way to store a bunch of strings instead of using array of char *?

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  • c incompatible types in assignment, problem with pointers?

    - by Fantastic Fourier
    Hi I'm working with C and I have a question about assigning pointers. struct foo { int _bar; char * _car[MAXINT]; // this is meant to be an array of char * so that it can hold pointers to names of cars } int foofunc (void * arg) { int bar; char * car[MAXINT]; struct foo thing = (struct foo *) arg; bar = arg->_bar; // this works fine car = arg->_car; // this gives compiler errors of incompatible types in assignment } car and _car have same declaration so why am I getting an error about incompatible types? My guess is that it has something to do with them being pointers (because they are pointers to arrays of char *, right?) but I don't see why that is a problem. when i declared char * car; instead of char * car[MAXINT]; it compiles fine. but I don't see how that would be useful to me later when I need to access certain info using index, it would be very annoying to access that info later. in fact, I'm not even sure if I am going about the right way, maybe there is a better way to store a bunch of strings instead of using array of char *?

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  • If statement question iphone?

    - by NextRev
    I am creating a game where where you complete shapes and the area gets filled in. However, if there is an enemy bird within your shape, it will not fill in. I want to make it so that if you do trap a bird within your shape, you will lose a life. How can I write an if statement that pretty much says if the below code doesn't take place, then you lose a life. If it helps losing a life is called doDie in my code. -(void)fillMutablePath{ CGPoint movePoint = CGPointFromString([pointsToFillArray objectAtIndex:0]); CGPathMoveToPoint(fillPath, NULL, movePoint.x, movePoint.y); for (int i=0; i<[pointsToFillArray count]; i++) { CGPoint tempPoint = CGPointFromString([pointsToFillArray objectAtIndex:i]); CGPathAddLineToPoint(fillPath, NULL, tempPoint.x, tempPoint.y); } CGContextAddPath(gameViewObj._myContext, fillPath); CGContextFillPath(gameViewObj._myContext); CGPathRelease(fillPath); [pointsToFillArray removeAllObjects]; } if(fillMutablePath doesn't take place when making a shape){ [self doDie]; } Like i said above, the reason fillMutablePath wouldn't take place is because a bird would be trapped within the shape. Any help would be much appreciated!!

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  • Questions about game states

    - by MrPlow
    I'm trying to make a framework for a game I've wanted to do for quite a while. The first thing that I decided to implement was a state system for game states. When my "original" idea of having a doubly linked list of game states failed I found This blog and liked the idea of a stack based game state manager. However there were a few things I found weird: Instead of RAII two class methods are used to initialize and destroy the state Every game state class is a singleton(and singletons are bad aren't they?) Every GameState object is static So I took the idea and altered a few things and got this: GameState.h class GameState { private: bool m_paused; protected: StateManager& m_manager; public: GameState(StateManager& manager) : m_manager(manager), m_paused(false){} virtual ~GameState() {} virtual void update() = 0; virtual void draw() = 0; virtual void handleEvents() = 0; void pause() { m_paused = true; } void resume() { m_paused = false; } void changeState(std::unique_ptr<GameState> state) { m_manager.changeState(std::move(state)); } }; StateManager.h class GameState; class StateManager { private: std::vector< std::unique_ptr<GameState> > m_gameStates; public: StateManager(); void changeState(std::unique_ptr<GameState> state); void StateManager::pushState(std::unique_ptr<GameState> state); void popState(); void update(); void draw(); void handleEvents(); }; StateManager.cpp StateManager::StateManager() {} void StateManager::changeState( std::unique_ptr<GameState> state ) { if(!m_gameStates.empty()) { m_gameStates.pop_back(); } m_gameStates.push_back( std::move(state) ); } void StateManager::pushState(std::unique_ptr<GameState> state) { if(!m_gameStates.empty()) { m_gameStates.back()->pause(); } m_gameStates.push_back( std::move(state) ); } void StateManager::popState() { if(!m_gameStates.empty()) m_gameStates.pop_back(); } void StateManager::update() { if(!m_gameStates.empty()) m_gameStates.back()->update(); } void StateManager::draw() { if(!m_gameStates.empty()) m_gameStates.back()->draw(); } void StateManager::handleEvents() { if(!m_gameStates.empty()) m_gameStates.back()->handleEvents(); } And it's used like this: main.cpp StateManager states; states.changeState( std::unique_ptr<GameState>(new GameStateIntro(states)) ); while(gamewindow::gameWindow.isOpen()) { states.handleEvents(); states.update(); states.draw(); } Constructors/Destructors are used to create/destroy states instead of specialized class methods, state objects are no longer static but

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  • How to read some bytes from BYTE*

    - by chekalin-v
    I have BYTE pointer. For example the length of this BYTE array is 10. How can I read 4 bytes from 3 position BYTE array? Now I doing it so BYTE *source = "1234567890\0"; BYTE* tmp = new BYTE[4+1](); for(int i=0; i<4; i++) { tmp[i] = source[i+3]; }

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  • What could cause a returning function to crash? C++

    - by JeanOTF
    So I have been debugging this error for hours now. I writing a program using Ogre3d relevant only because it doesn't load symbols so it doesn't let me stack trace which made finding the location of the crash even harder. So, write before I call a specific function I print out "Starting" then I call the function and immediately after I print "Stopping". Throughout the function I print out letters A-F where F is printed right before the function returns (one line above the last '}') The weird thing is when the crash occurs it is after the 'F' is printed but there is no 'Stopping'. Does this mean that the crash is happening in between somewhere? The only thing I can think of is something going wrong during the deallocation of some of the memory allocated during the function. I've never had anything happen like this, I will keep checking to make sure it's going wrong where I think it is.

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  • Problems Allocating Objects of Derived Class Where Base Class has Abstract Virtual Functions

    - by user1743901
    I am trying to get this Zombie/Human agent based simulation running, but I am having problems with these derived classes (Human and Zombie) who have parent class "Creature". I have 3 virtual functions declared in "Creature" and all three of these are re-declared AND DEFINED in both "Human" and "Zombie". But for some reason when I have my program call "new" to allocate memory for objects of type Human or Zombie, it complains about the virtual functions being abstract. Here's the code: definitions.h #ifndef definitions_h #define definitions_h class Creature; class Item; class Coords; class Grid { public: Creature*** cboard; Item*** iboard; int WIDTH; int HEIGHT; Grid(int WIDTHVALUE, int HEIGHTVALUE); void FillGrid(); //initializes grid object with humans and zombies void Refresh(); //calls Creature::Die(),Move(),Attack(),Breed() on every square void UpdateBuffer(char** buffer); bool isEmpty(int startx, int starty, int dir); char CreatureType(int xcoord, int ycoord); char CreatureType(int startx, int starty, int dir); }; class Random { public: int* rptr; void Print(); Random(int MIN, int MAX, int LEN); ~Random(); private: bool alreadyused(int checkthis, int len, int* rptr); bool isClean(); int len; }; class Coords { public: int x; int y; int MaxX; int MaxY; Coords() {x=0; y=0; MaxX=0; MaxY=0;} Coords(int X, int Y, int WIDTH, int HEIGHT) {x=X; y=Y; MaxX=WIDTH; MaxY=HEIGHT; } void MoveRight(); void MoveLeft(); void MoveUp(); void MoveDown(); void MoveUpRight(); void MoveUpLeft(); void MoveDownRight(); void MoveDownLeft(); void MoveDir(int dir); void setx(int X) {x=X;} void sety(int Y) {y=Y;} }; class Creature { public: bool alive; Coords Location; char displayletter; Creature() {Location.x=0; Location.y=0;} Creature(int i, int j) {Location.setx(i); Location.sety(j);} virtual void Attack() =0; virtual void AttackCreature(Grid G, int attackdirection) =0; virtual void Breed() =0; void Die(); void Move(Grid G); int DecideSquare(Grid G); void MoveTo(Grid G, int dir); }; class Human : public Creature { public: bool armed; //if armed, chances of winning fight increased for next fight bool vaccinated; //if vaccinated, no chance of getting infected int bitecount; //if a human is bitten, bite count is set to a random number int breedcount; //if a human goes x steps without combat, will breed if next to a human int starvecount; //if a human does not eat in x steps, will die Human() {displayletter='H';} Human(int i, int j) {displayletter='H';} void Attack(Grid G); void AttackCreature(Grid G, int attackdirection); void Breed(Grid G); //will breed after x steps and next to human int DecideAttack(Grid G); }; class Zombie : public Creature { public: Zombie() {displayletter='Z';} Zombie(int i, int j) {displayletter='Z';} void Attack(Grid G); void AttackCreature(Grid G, int attackdirection); void Breed() {} //does nothing int DecideAttack(Grid G); void AttackCreature(Grid G, int attackdirection); }; class Item { }; #endif definitions.cpp #include <cstdlib> #include "definitions.h" Random::Random(int MIN, int MAX, int LEN) //constructor { len=LEN; rptr=new int[LEN]; //allocate array of given length for (int i=0; i<LEN; i++) { int random; do { random = rand() % (MAX-MIN+1) + MIN; } while (alreadyused(random,LEN,rptr)); rptr[i]=random; } } bool Random::alreadyused(int checkthis, int len, int* rptr) { for (int i=0; i<len; i++) { if (rptr[i]==checkthis) return 1; } return 0; } Random::~Random() { delete rptr; } Grid::Grid(int WIDTHVALUE, int HEIGHTVALUE) { WIDTH = WIDTHVALUE; HEIGHT = HEIGHTVALUE; //builds 2d array of creature pointers cboard = new Creature**[WIDTH]; for(int i=0; i<WIDTH; i++) { cboard[i] = new Creature*[HEIGHT]; } //builds 2d array of item pointers iboard = new Item**[WIDTH]; for (int i=0; i<WIDTH; i++) { iboard[i] = new Item*[HEIGHT]; } } void Grid::FillGrid() { /* For each creature pointer in grid, randomly selects whether to initalize as zombie, human, or empty square. This methodology can be changed to initialize different creature types with different probabilities */ int random; for (int i=0; i<WIDTH; i++) { for (int j=0; j<HEIGHT; j++) { Random X(1,100,1); //create a single random integer from [1,100] at X.rptr random=*(X.rptr); if (random < 20) cboard[i][j] = new Human(i,j); else if (random < 40) cboard[i][j] = new Zombie(i,j); else cboard[i][j] = NULL; } } //at this point every creature pointer should be pointing to either //a zombie, human, or NULL with varying probabilities } void Grid::UpdateBuffer(char** buffer) { for (int i=0; i<WIDTH; i++) { for (int j=0; j<HEIGHT; j++) { if (cboard[i][j]) buffer[i][j]=cboard[i][j]->displayletter; else buffer[i][j]=' '; } } } bool Grid::isEmpty(int startx, int starty, int dir) { Coords StartLocation(startx,starty,WIDTH,HEIGHT); switch(dir) { case 1: StartLocation.MoveUp(); if (cboard[StartLocation.x][StartLocation.y]) return 0; case 2: StartLocation.MoveUpRight(); if (cboard[StartLocation.x][StartLocation.y]) return 0; case 3: StartLocation.MoveRight(); if (cboard[StartLocation.x][StartLocation.y]) return 0; case 4: StartLocation.MoveDownRight(); if (cboard[StartLocation.x][StartLocation.y]) return 0; case 5: StartLocation.MoveDown(); if (cboard[StartLocation.x][StartLocation.y]) return 0; case 6: StartLocation.MoveDownLeft(); if (cboard[StartLocation.x][StartLocation.y]) return 0; case 7: StartLocation.MoveLeft(); if (cboard[StartLocation.x][StartLocation.y]) return 0; case 8: StartLocation.MoveUpLeft(); if (cboard[StartLocation.x][StartLocation.y]) return 0; } return 1; } char Grid::CreatureType(int xcoord, int ycoord) { if (cboard[xcoord][ycoord]) //if there is a creature at location xcoord,ycoord return (cboard[xcoord][ycoord]->displayletter); else //if pointer at location xcoord,ycoord is null, return null char return '\0'; } char Grid::CreatureType(int startx, int starty, int dir) { Coords StartLocation(startx,starty,WIDTH,HEIGHT); switch(dir) { case 1: StartLocation.MoveUp(); if (cboard[StartLocation.x][StartLocation.y]) return (cboard[StartLocation.x][StartLocation.y]->displayletter); case 2: StartLocation.MoveUpRight(); if (cboard[StartLocation.x][StartLocation.y]) return (cboard[StartLocation.x][StartLocation.y]->displayletter); case 3: StartLocation.MoveRight(); if (cboard[StartLocation.x][StartLocation.y]) return (cboard[StartLocation.x][StartLocation.y]->displayletter); case 4: StartLocation.MoveDownRight(); if (cboard[StartLocation.x][StartLocation.y]) return (cboard[StartLocation.x][StartLocation.y]->displayletter); case 5: StartLocation.MoveDown(); if (cboard[StartLocation.x][StartLocation.y]) return (cboard[StartLocation.x][StartLocation.y]->displayletter); case 6: StartLocation.MoveDownLeft(); if (cboard[StartLocation.x][StartLocation.y]) return (cboard[StartLocation.x][StartLocation.y]->displayletter); case 7: StartLocation.MoveLeft(); if (cboard[StartLocation.x][StartLocation.y]) return (cboard[StartLocation.x][StartLocation.y]->displayletter); case 8: StartLocation.MoveUpLeft(); if (cboard[StartLocation.x][StartLocation.y]) return (cboard[StartLocation.x][StartLocation.y]->displayletter); } //if function hasn't returned by now, square being looked at is pointer to null return '\0'; //return null char } void Coords::MoveRight() {(x==MaxX)? (x=0):(x++);} void Coords::MoveLeft() {(x==0)? (x=MaxX):(x--);} void Coords::MoveUp() {(y==0)? (y=MaxY):(y--);} void Coords::MoveDown() {(y==MaxY)? (y=0):(y++);} void Coords::MoveUpRight() {MoveUp(); MoveRight();} void Coords::MoveUpLeft() {MoveUp(); MoveLeft();} void Coords::MoveDownRight() {MoveDown(); MoveRight();} void Coords::MoveDownLeft() {MoveDown(); MoveLeft();} void Coords::MoveDir(int dir) { switch(dir) { case 1: MoveUp(); break; case 2: MoveUpRight(); break; case 3: MoveRight(); break; case 4: MoveDownRight(); break; case 5: MoveDown(); break; case 6: MoveDownLeft(); break; case 7: MoveLeft(); break; case 8: MoveUpLeft(); break; case 0: break; } } void Creature::Move(Grid G) { int movedir=DecideSquare(G); MoveTo(G,movedir); } int Creature::DecideSquare(Grid G) { Random X(1,8,8); //X.rptr now points to 8 unique random integers from [1,8] for (int i=0; i<8; i++) { int dir=X.rptr[i]; if (G.isEmpty(Location.x,Location.y,dir)) return dir; } return 0; } void Creature::MoveTo(Grid G, int dir) { Coords OldLocation=Location; Location.MoveDir(dir); G.cboard[Location.x][Location.y]=this; //point new location to this creature G.cboard[OldLocation.x][OldLocation.y]=NULL; //point old location to NULL } void Creature::Die() { if (!alive) { delete this; this=NULL; } } void Human::Breed(Grid G) { if (!breedcount) { Coords BreedLocation=Location; Random X(1,8,8); for (int i=0; i<8; i++) { BreedLocation.MoveDir(X.rptr[i]); if (!G.cboard[BreedLocation.x][BreedLocation.y]) { G.cboard[BreedLocation.x][BreedLocation.y])=new Human(BreedLocation.x,BreedLocation.y); return; } } } } int Human::DecideAttack(Grid G) { Coords AttackLocation=Location; Random X(1,8,8); int attackdir; for (int i=0; i<8; i++) { attackdir=X.rptr[i]; switch(G.CreatureType(Location.x,Location.y,attackdir)) { case 'H': break; case 'Z': return attackdir; case '\0': break; default: break; } } return 0; //no zombies! } int AttackRoll(int para1, int para2) { //outcome 1: Zombie wins, human dies //outcome 2: Human wins, zombie dies //outcome 3: Human wins, zombie dies, but human is bitten Random X(1,100,1); int roll= *(X.rptr); if (roll < para1) return 1; else if (roll < para2) return 2; else return 3; } void Human::AttackCreature(Grid G, int attackdirection) { Coords AttackLocation=Location; AttackLocation.MoveDir(attackdirection); int para1=33; int para2=33; if (vaccinated) para2=101; //makes attackroll > para 2 impossible, never gets infected if (armed) para1-=16; //reduces chance of zombie winning fight int roll=AttackRoll(para1,para2); //outcome 1: Zombie wins, human dies //outcome 2: Human wins, zombie dies //outcome 3: Human wins, zombie dies, but human is bitten switch(roll) { case 1: alive=0; //human (this) dies return; case 2: G.cboard[AttackLocation.x][AttackLocation.y]->alive=0; return; //zombie dies case 3: G.cboard[AttackLocation.x][AttackLocation.y]->alive=0; //zombie dies Random X(3,7,1); //human is bitten bitecount=*(X.rptr); return; } } int Zombie::DecideAttack(Grid G) { Coords AttackLocation=Location; Random X(1,8,8); int attackdir; for (int i=0; i<8; i++) { attackdir=X.rptr[i]; switch(G.CreatureType(Location.x,Location.y,attackdir)) { case 'H': return attackdir; case 'Z': break; case '\0': break; default: break; } } return 0; //no zombies! } void Zombie::AttackCreature(Grid G, int attackdirection) { int reversedirection; if (attackdirection < 9 && attackdirection>0) { (attackdirection<5)? (reversedirection=attackdirection+4):(reversedirection=attackdirection-4); } else reversedirection=0; //this should never happen //when a zombie attacks a human, the Human::AttackZombie() function is called //in the "reverse" direction, utilizing that function that has already been written Coords ZombieLocation=Location; Coords HumanLocation=Location; HumanLocation.MoveDir(attackdirection); if (G.cboard[HumanLocation.x][HumanLocation.y]) //if there is a human there, which there should be G.cboard[HumanLocation.x][HumanLocation.y]->AttackCreature(G,reversedirection); } void Zombie::Attack(Grid G) { int attackdirection=DecideAttack(G); AttackCreature(G,attackdirection); } main.cpp #include <cstdlib> #include <iostream> #include "definitions.h" using namespace std; int main(int argc, char *argv[]) { Grid G(500,500); system("PAUSE"); return EXIT_SUCCESS; }

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  • When and why you should use void (instead of i.e. bool/int)

    - by Jonas
    I occasionally run into methods where a developer chose to return something which isn't critical to the function. I mean, when looking at the code, it apparently works just as nice as a void and after a moment of thought, I ask "Why?" Does this sound familiar? Sometimes I would agree that most often it is better to return something like a bool or int, rather then just do a void. I'm not sure though, in the big picture, about the pros and cons. Depending on situation, returning an int can make the caller aware of the amount of rows or objects affected by the method (e.g., 5 records saved to MSSQL). If a method like "InsertSomething" returns a boolean, I can have the method designed to return true if success, else false. The caller can choose to act or not on that information. On the other hand, May it lead to a less clear purpose of a method call? Bad coding often forces me to double-check the method content. If it returns something, it tells you that the method is of a type you have to do something with the returned result. Another issue would be, if the method implementation is unknown to you, what did the developer decide to return that isn't function critical? Of course you can comment it. The return value has to be processed, when the processing could be ended at the closing bracket of method. What happens under the hood? Did the called method get false because of a thrown error? Or did it return false due to the evaluated result? What are your experiences with this? How would you act on this?

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  • Why can't `main` return a double or String rather than int or void?

    - by sunny
    In many languages such as C, C++, and Java, the main method/function has a return type of void or int, but not double or String. What might be the reasons behind that? I know a little bit that we can't do that because main is called by runtime library and it expects some syntax like int main() or int main(int,char**) so we have to stick to that. So my question is: why does main have the type signature that it has, and not a different one?

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  • Linker errors between multiple projects in Visual C++

    - by rlbond
    Hi, I have a solution with multiple projects. I have a "main" project, which acts as a menu and from there, the user can access any of the other projects. On this main project, I get linker errors for every function called. How do I avoid these linker errors? I set the project dependencies already in the "Project Dependencies..." dialog. Thanks EDIT -- I did as suggested and added the output folder to the linker's additional directories. Now, however, I get a million errors as follows: 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: void __thiscall std::basic_ios ::setstate(int,bool)" (?setstate@?$basic_ios@DU?$char_traits@D@std@@@std@@QAEXH_N@Z) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: int __thiscall std::ios_base::width(int)" (?width@ios_base@std@@QAEHH@Z) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: int __thiscall std::basic_streambuf ::sputn(char const *,int)" (?sputn@?$basic_streambuf@DU?$char_traits@D@std@@@std@@QAEHPBDH@Z) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: static bool __cdecl std::char_traits::eq_int_type(int const &,int const &)" (?eq_int_type@?$char_traits@D@std@@SA_NABH0@Z) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: static int __cdecl std::char_traits::eof(void)" (?eof@?$char_traits@D@std@@SAHXZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: int __thiscall std::basic_streambuf ::sputc(char)" (?sputc@?$basic_streambuf@DU?$char_traits@D@std@@@std@@QAEHD@Z) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: class std::basic_streambuf * __thiscall std::basic_ios ::rdbuf(void)const " (?rdbuf@?$basic_ios@DU?$char_traits@D@std@@@std@@QBEPAV?$basic_streambuf@DU?$char_traits@D@std@@@2@XZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: char __thiscall std::basic_ios ::fill(void)const " (?fill@?$basic_ios@DU?$char_traits@D@std@@@std@@QBEDXZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: int __thiscall std::ios_base::flags(void)const " (?flags@ios_base@std@@QBEHXZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: int __thiscall std::ios_base::width(void)const " (?width@ios_base@std@@QBEHXZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: static unsigned int __cdecl std::char_traits::length(char const *)" (?length@?$char_traits@D@std@@SAIPBD@Z) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: class std::basic_ostream & __thiscall std::basic_ostream ::flush(void)" (?flush@?$basic_ostream@DU?$char_traits@D@std@@@std@@QAEAAV12@XZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: class std::basic_ostream * __thiscall std::basic_ios ::tie(void)const " (?tie@?$basic_ios@DU?$char_traits@D@std@@@std@@QBEPAV?$basic_ostream@DU?$char_traits@D@std@@@2@XZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: bool __thiscall std::ios_base::good(void)const " (?good@ios_base@std@@QBE_NXZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: void __thiscall std::basic_ostream ::_Osfx(void)" (?_Osfx@?$basic_ostream@DU?$char_traits@D@std@@@std@@QAEXXZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: void __thiscall std::basic_streambuf ::_Lock(void)" (?_Lock@?$basic_streambuf@DU?$char_traits@D@std@@@std@@QAEXXZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: void __thiscall std::basic_streambuf ::_Unlock(void)" (?_Unlock@?$basic_streambuf@DU?$char_traits@D@std@@@std@@QAEXXZ) already defined in panels.lib(panel_main.obj) 3msvcprtd.lib(MSVCP90D.dll) : error LNK2005: "public: class std::locale::facet * __thiscall std::locale::facet::_Decref(void)" (?_Decref@facet@locale@std@@QAEPAV123@XZ) already defined in panels.lib(panel_main.obj) 3libcpmtd.lib(ios.obj) : error LNK2005: "private: static void __cdecl std::ios_base::_Ios_base_dtor(class std::ios_base *)" (?_Ios_base_dtor@ios_base@std@@CAXPAV12@@Z) already defined in msvcprtd.lib(MSVCP90D.dll) 3libcpmtd.lib(ios.obj) : error LNK2005: "public: static void __cdecl std::ios_base::_Addstd(class std::ios_base *)" (?_Addstd@ios_base@std@@SAXPAV12@@Z) already defined in msvcprtd.lib(MSVCP90D.dll) 3libcpmtd.lib(locale0.obj) : error LNK2005: "void __cdecl _AtModuleExit(void (__cdecl*)(void))" (?_AtModuleExit@@YAXP6AXXZ@Z) already defined in msvcprtd.lib(locale0_implib.obj) 3libcpmtd.lib(locale0.obj) : error LNK2005: __Fac_tidy already defined in msvcprtd.lib(locale0_implib.obj) 3libcpmtd.lib(locale0.obj) : error LNK2005: "private: static void __cdecl std::locale::facet::facet_Register(class std::locale::facet *)" (?facet_Register@facet@locale@std@@CAXPAV123@@Z) already defined in msvcprtd.lib(locale0_implib.obj) 3libcpmtd.lib(locale0.obj) : error LNK2005: "private: static class std::locale::_Locimp * __cdecl std::locale::_Getgloballocale(void)" (?_Getgloballocale@locale@std@@CAPAV_Locimp@12@XZ) already defined in msvcprtd.lib(MSVCP90D.dll) 3libcpmtd.lib(locale0.obj) : error LNK2005: "private: static class std::locale::_Locimp * __cdecl std::locale::_Init(void)" (?_Init@locale@std@@CAPAV_Locimp@12@XZ) already defined in msvcprtd.lib(MSVCP90D.dll) 3libcpmtd.lib(locale0.obj) : error LNK2005: "public: static void __cdecl std::_Locinfo::_Locinfo_ctor(class std::_Locinfo *,class std::basic_string,class std::allocator const &)" (?_Locinfo_ctor@_Locinfo@std@@SAXPAV12@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@2@@Z) already defined in msvcprtd.lib(MSVCP90D.dll) 3libcpmtd.lib(locale0.obj) : error LNK2005: "public: static void __cdecl std::_Locinfo::_Locinfo_dtor(class std::_Locinfo *)" (?_Locinfo_dtor@_Locinfo@std@@SAXPAV12@@Z) already defined in msvcprtd.lib(MSVCP90D.dll) 3libcpmtd.lib(xlock.obj) : error LNK2005: "public: __thiscall std::_Lockit::_Lockit(int)" (??0_Lockit@std@@QAE@H@Z) already defined in msvcprtd.lib(MSVCP90D.dll) 3libcpmtd.lib(xlock.obj) : error LNK2005: "public: __thiscall std::_Lockit::~_Lockit(void)" (??1_Lockit@std@@QAE@XZ) already defined in msvcprtd.lib(MSVCP90D.dll)

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  • Count seconds and minutes with MCU timer/interrupt?

    - by arynhard
    I am trying to figure out how to create a timer for my C8051F020 MCU. The following code uses the value passed to init_Timer2() with the following formula: 65535-(0.1 / (12/2000000)=48868. I set up the timer to count every time it executes and for every 10 counts, count one second. This is based on the above formula. 48868 when passed to init_Timer2 will produce a 0.1 second delay. It would take ten of them per second. However, when I test the timer it is a little fast. At ten seconds the timer reports 11 seconds, at 20 seconds the timer reports 22 seconds. I would like to get as close to a perfect second as I can. Here is my code: #include <compiler_defs.h> #include <C8051F020_defs.h> void init_Clock(void); void init_Watchdog(void); void init_Ports(void); void init_Timer2(unsigned int counts); void start_Timer2(void); void timer2_ISR(void); unsigned int timer2_Count; unsigned int seconds; unsigned int minutes; int main(void) { init_Clock(); init_Watchdog(); init_Ports(); start_Timer2(); P5 &= 0xFF; while (1); } //============================================================= //Functions //============================================================= void init_Clock(void) { OSCICN = 0x04; //2Mhz //OSCICN = 0x07; //16Mhz } void init_Watchdog(void) { //Disable watchdog timer WDTCN = 0xDE; WDTCN = 0xAD; } void init_Ports(void) { XBR0 = 0x00; XBR1 = 0x00; XBR2 = 0x40; P0 = 0x00; P0MDOUT = 0x00; P5 = 0x00; //Set P5 to 1111 P74OUT = 0x08; //Set P5 4 - 7 (LEDs) to push pull (Output) } void init_Timer2(unsigned int counts) { CKCON = 0x00; //Set all timers to system clock divided by 12 T2CON = 0x00; //Set timer 2 to timer mode RCAP2 = counts; T2 = 0xFFFF; //655535 IE |= 0x20; //Enable timer 2 T2CON |= 0x04; //Start timer 2 } void start_Timer2(void) { EA = 0; init_Timer2(48868); EA = 1; } void timer2_ISR(void) interrupt 5 { T2CON &= ~(0x80); P5 ^= 0xF0; timer2_Count++; if(timer2_Count % 10 == 0) { seconds++; } if(seconds % 60 == 0 && seconds != 0) { minutes++; } }

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  • Help with Collision Resolution?

    - by Milo
    I'm trying to learn about physics by trying to make a simplified GTA 2 clone. My only problem is collision resolution. Everything else works great. I have a rigid body class and from there cars and a wheel class: class RigidBody extends Entity { //linear private Vector2D velocity = new Vector2D(); private Vector2D forces = new Vector2D(); private OBB2D predictionRect = new OBB2D(new Vector2D(), 1.0f, 1.0f, 0.0f); private float mass; private Vector2D deltaVec = new Vector2D(); private Vector2D v = new Vector2D(); //angular private float angularVelocity; private float torque; private float inertia; //graphical private Vector2D halfSize = new Vector2D(); private Bitmap image; private Matrix mat = new Matrix(); private float[] Vector2Ds = new float[2]; private Vector2D tangent = new Vector2D(); private static Vector2D worldRelVec = new Vector2D(); private static Vector2D relWorldVec = new Vector2D(); private static Vector2D pointVelVec = new Vector2D(); public RigidBody() { //set these defaults so we don't get divide by zeros mass = 1.0f; inertia = 1.0f; setLayer(LAYER_OBJECTS); } protected void rectChanged() { if(getWorld() != null) { getWorld().updateDynamic(this); } } //intialize out parameters public void initialize(Vector2D halfSize, float mass, Bitmap bitmap) { //store physical parameters this.halfSize = halfSize; this.mass = mass; image = bitmap; inertia = (1.0f / 20.0f) * (halfSize.x * halfSize.x) * (halfSize.y * halfSize.y) * mass; RectF rect = new RectF(); float scalar = 10.0f; rect.left = (int)-halfSize.x * scalar; rect.top = (int)-halfSize.y * scalar; rect.right = rect.left + (int)(halfSize.x * 2.0f * scalar); rect.bottom = rect.top + (int)(halfSize.y * 2.0f * scalar); setRect(rect); predictionRect.set(rect); } public void setLocation(Vector2D position, float angle) { getRect().set(position, getWidth(), getHeight(), angle); rectChanged(); } public void setPredictionLocation(Vector2D position, float angle) { getPredictionRect().set(position, getWidth(), getHeight(), angle); } public void setPredictionCenter(Vector2D center) { getPredictionRect().moveTo(center); } public void setPredictionAngle(float angle) { predictionRect.setAngle(angle); } public Vector2D getPosition() { return getRect().getCenter(); } public OBB2D getPredictionRect() { return predictionRect; } @Override public void update(float timeStep) { doUpdate(false,timeStep); } public void doUpdate(boolean prediction, float timeStep) { //integrate physics //linear Vector2D acceleration = Vector2D.scalarDivide(forces, mass); if(prediction) { Vector2D velocity = Vector2D.add(this.velocity, Vector2D.scalarMultiply(acceleration, timeStep)); Vector2D c = getRect().getCenter(); c = Vector2D.add(getRect().getCenter(), Vector2D.scalarMultiply(velocity , timeStep)); setPredictionCenter(c); //forces = new Vector2D(0,0); //clear forces } else { velocity.x += (acceleration.x * timeStep); velocity.y += (acceleration.y * timeStep); //velocity = Vector2D.add(velocity, Vector2D.scalarMultiply(acceleration, timeStep)); Vector2D c = getRect().getCenter(); v.x = getRect().getCenter().getX() + (velocity.x * timeStep); v.y = getRect().getCenter().getY() + (velocity.y * timeStep); deltaVec.x = v.x - c.x; deltaVec.y = v.y - c.y; deltaVec.normalize(); setCenter(v.x, v.y); forces.x = 0; //clear forces forces.y = 0; } //angular float angAcc = torque / inertia; if(prediction) { float angularVelocity = this.angularVelocity + angAcc * timeStep; setPredictionAngle(getAngle() + angularVelocity * timeStep); //torque = 0; //clear torque } else { angularVelocity += angAcc * timeStep; setAngle(getAngle() + angularVelocity * timeStep); torque = 0; //clear torque } } public void updatePrediction(float timeStep) { doUpdate(true, timeStep); } //take a relative Vector2D and make it a world Vector2D public Vector2D relativeToWorld(Vector2D relative) { mat.reset(); Vector2Ds[0] = relative.x; Vector2Ds[1] = relative.y; mat.postRotate(JMath.radToDeg(getAngle())); mat.mapVectors(Vector2Ds); relWorldVec.x = Vector2Ds[0]; relWorldVec.y = Vector2Ds[1]; return new Vector2D(Vector2Ds[0], Vector2Ds[1]); } //take a world Vector2D and make it a relative Vector2D public Vector2D worldToRelative(Vector2D world) { mat.reset(); Vector2Ds[0] = world.x; Vector2Ds[1] = world.y; mat.postRotate(JMath.radToDeg(-getAngle())); mat.mapVectors(Vector2Ds); return new Vector2D(Vector2Ds[0], Vector2Ds[1]); } //velocity of a point on body public Vector2D pointVelocity(Vector2D worldOffset) { tangent.x = -worldOffset.y; tangent.y = worldOffset.x; return Vector2D.add( Vector2D.scalarMultiply(tangent, angularVelocity) , velocity); } public void applyForce(Vector2D worldForce, Vector2D worldOffset) { //add linear force forces.x += worldForce.x; forces.y += worldForce.y; //add associated torque torque += Vector2D.cross(worldOffset, worldForce); } @Override public void draw( GraphicsContext c) { c.drawRotatedScaledBitmap(image, getPosition().x, getPosition().y, getWidth(), getHeight(), getAngle()); } public Vector2D getVelocity() { return velocity; } public void setVelocity(Vector2D velocity) { this.velocity = velocity; } public Vector2D getDeltaVec() { return deltaVec; } } Vehicle public class Wheel { private Vector2D forwardVec; private Vector2D sideVec; private float wheelTorque; private float wheelSpeed; private float wheelInertia; private float wheelRadius; private Vector2D position = new Vector2D(); public Wheel(Vector2D position, float radius) { this.position = position; setSteeringAngle(0); wheelSpeed = 0; wheelRadius = radius; wheelInertia = (radius * radius) * 1.1f; } public void setSteeringAngle(float newAngle) { Matrix mat = new Matrix(); float []vecArray = new float[4]; //forward Vector vecArray[0] = 0; vecArray[1] = 1; //side Vector vecArray[2] = -1; vecArray[3] = 0; mat.postRotate(newAngle / (float)Math.PI * 180.0f); mat.mapVectors(vecArray); forwardVec = new Vector2D(vecArray[0], vecArray[1]); sideVec = new Vector2D(vecArray[2], vecArray[3]); } public void addTransmissionTorque(float newValue) { wheelTorque += newValue; } public float getWheelSpeed() { return wheelSpeed; } public Vector2D getAnchorPoint() { return position; } public Vector2D calculateForce(Vector2D relativeGroundSpeed, float timeStep, boolean prediction) { //calculate speed of tire patch at ground Vector2D patchSpeed = Vector2D.scalarMultiply(Vector2D.scalarMultiply( Vector2D.negative(forwardVec), wheelSpeed), wheelRadius); //get velocity difference between ground and patch Vector2D velDifference = Vector2D.add(relativeGroundSpeed , patchSpeed); //project ground speed onto side axis Float forwardMag = new Float(0.0f); Vector2D sideVel = velDifference.project(sideVec); Vector2D forwardVel = velDifference.project(forwardVec, forwardMag); //calculate super fake friction forces //calculate response force Vector2D responseForce = Vector2D.scalarMultiply(Vector2D.negative(sideVel), 2.0f); responseForce = Vector2D.subtract(responseForce, forwardVel); float topSpeed = 500.0f; //calculate torque on wheel wheelTorque += forwardMag * wheelRadius; //integrate total torque into wheel wheelSpeed += wheelTorque / wheelInertia * timeStep; //top speed limit (kind of a hack) if(wheelSpeed > topSpeed) { wheelSpeed = topSpeed; } //clear our transmission torque accumulator wheelTorque = 0; //return force acting on body return responseForce; } public void setTransmissionTorque(float newValue) { wheelTorque = newValue; } public float getTransmissionTourque() { return wheelTorque; } public void setWheelSpeed(float speed) { wheelSpeed = speed; } } //our vehicle object public class Vehicle extends RigidBody { private Wheel [] wheels = new Wheel[4]; private boolean throttled = false; public void initialize(Vector2D halfSize, float mass, Bitmap bitmap) { //front wheels wheels[0] = new Wheel(new Vector2D(halfSize.x, halfSize.y), 0.45f); wheels[1] = new Wheel(new Vector2D(-halfSize.x, halfSize.y), 0.45f); //rear wheels wheels[2] = new Wheel(new Vector2D(halfSize.x, -halfSize.y), 0.75f); wheels[3] = new Wheel(new Vector2D(-halfSize.x, -halfSize.y), 0.75f); super.initialize(halfSize, mass, bitmap); } public void setSteering(float steering) { float steeringLock = 0.13f; //apply steering angle to front wheels wheels[0].setSteeringAngle(steering * steeringLock); wheels[1].setSteeringAngle(steering * steeringLock); } public void setThrottle(float throttle, boolean allWheel) { float torque = 85.0f; throttled = true; //apply transmission torque to back wheels if (allWheel) { wheels[0].addTransmissionTorque(throttle * torque); wheels[1].addTransmissionTorque(throttle * torque); } wheels[2].addTransmissionTorque(throttle * torque); wheels[3].addTransmissionTorque(throttle * torque); } public void setBrakes(float brakes) { float brakeTorque = 15.0f; //apply brake torque opposing wheel vel for (Wheel wheel : wheels) { float wheelVel = wheel.getWheelSpeed(); wheel.addTransmissionTorque(-wheelVel * brakeTorque * brakes); } } public void doUpdate(float timeStep, boolean prediction) { for (Wheel wheel : wheels) { float wheelVel = wheel.getWheelSpeed(); //apply negative force to naturally slow down car if(!throttled && !prediction) wheel.addTransmissionTorque(-wheelVel * 0.11f); Vector2D worldWheelOffset = relativeToWorld(wheel.getAnchorPoint()); Vector2D worldGroundVel = pointVelocity(worldWheelOffset); Vector2D relativeGroundSpeed = worldToRelative(worldGroundVel); Vector2D relativeResponseForce = wheel.calculateForce(relativeGroundSpeed, timeStep,prediction); Vector2D worldResponseForce = relativeToWorld(relativeResponseForce); applyForce(worldResponseForce, worldWheelOffset); } //no throttling yet this frame throttled = false; if(prediction) { super.updatePrediction(timeStep); } else { super.update(timeStep); } } @Override public void update(float timeStep) { doUpdate(timeStep,false); } public void updatePrediction(float timeStep) { doUpdate(timeStep,true); } public void inverseThrottle() { float scalar = 0.2f; for(Wheel wheel : wheels) { wheel.setTransmissionTorque(-wheel.getTransmissionTourque() * scalar); wheel.setWheelSpeed(-wheel.getWheelSpeed() * 0.1f); } } } And my big hack collision resolution: private void update() { camera.setPosition((vehicle.getPosition().x * camera.getScale()) - ((getWidth() ) / 2.0f), (vehicle.getPosition().y * camera.getScale()) - ((getHeight() ) / 2.0f)); //camera.move(input.getAnalogStick().getStickValueX() * 15.0f, input.getAnalogStick().getStickValueY() * 15.0f); if(input.isPressed(ControlButton.BUTTON_GAS)) { vehicle.setThrottle(1.0f, false); } if(input.isPressed(ControlButton.BUTTON_STEAL_CAR)) { vehicle.setThrottle(-1.0f, false); } if(input.isPressed(ControlButton.BUTTON_BRAKE)) { vehicle.setBrakes(1.0f); } vehicle.setSteering(input.getAnalogStick().getStickValueX()); //vehicle.update(16.6666666f / 1000.0f); boolean colided = false; vehicle.updatePrediction(16.66666f / 1000.0f); List<Entity> buildings = world.queryStaticSolid(vehicle,vehicle.getPredictionRect()); if(buildings.size() > 0) { colided = true; } if(!colided) { vehicle.update(16.66f / 1000.0f); } else { Vector2D delta = vehicle.getDeltaVec(); vehicle.setVelocity(Vector2D.negative(vehicle.getVelocity().multiply(0.2f)). add(delta.multiply(-1.0f))); vehicle.inverseThrottle(); } } Here is OBB public class OBB2D { // Corners of the box, where 0 is the lower left. private Vector2D corner[] = new Vector2D[4]; private Vector2D center = new Vector2D(); private Vector2D extents = new Vector2D(); private RectF boundingRect = new RectF(); private float angle; //Two edges of the box extended away from corner[0]. private Vector2D axis[] = new Vector2D[2]; private double origin[] = new double[2]; public OBB2D(Vector2D center, float w, float h, float angle) { set(center,w,h,angle); } public OBB2D(float left, float top, float width, float height) { set(new Vector2D(left + (width / 2), top + (height / 2)),width,height,0.0f); } public void set(Vector2D center,float w, float h,float angle) { Vector2D X = new Vector2D( (float)Math.cos(angle), (float)Math.sin(angle)); Vector2D Y = new Vector2D((float)-Math.sin(angle), (float)Math.cos(angle)); X = X.multiply( w / 2); Y = Y.multiply( h / 2); corner[0] = center.subtract(X).subtract(Y); corner[1] = center.add(X).subtract(Y); corner[2] = center.add(X).add(Y); corner[3] = center.subtract(X).add(Y); computeAxes(); extents.x = w / 2; extents.y = h / 2; computeDimensions(center,angle); } private void computeDimensions(Vector2D center,float angle) { this.center.x = center.x; this.center.y = center.y; this.angle = angle; boundingRect.left = Math.min(Math.min(corner[0].x, corner[3].x), Math.min(corner[1].x, corner[2].x)); boundingRect.top = Math.min(Math.min(corner[0].y, corner[1].y),Math.min(corner[2].y, corner[3].y)); boundingRect.right = Math.max(Math.max(corner[1].x, corner[2].x), Math.max(corner[0].x, corner[3].x)); boundingRect.bottom = Math.max(Math.max(corner[2].y, corner[3].y),Math.max(corner[0].y, corner[1].y)); } public void set(RectF rect) { set(new Vector2D(rect.centerX(),rect.centerY()),rect.width(),rect.height(),0.0f); } // Returns true if other overlaps one dimension of this. private boolean overlaps1Way(OBB2D other) { for (int a = 0; a < axis.length; ++a) { double t = other.corner[0].dot(axis[a]); // Find the extent of box 2 on axis a double tMin = t; double tMax = t; for (int c = 1; c < corner.length; ++c) { t = other.corner[c].dot(axis[a]); if (t < tMin) { tMin = t; } else if (t > tMax) { tMax = t; } } // We have to subtract off the origin // See if [tMin, tMax] intersects [0, 1] if ((tMin > 1 + origin[a]) || (tMax < origin[a])) { // There was no intersection along this dimension; // the boxes cannot possibly overlap. return false; } } // There was no dimension along which there is no intersection. // Therefore the boxes overlap. return true; } //Updates the axes after the corners move. Assumes the //corners actually form a rectangle. private void computeAxes() { axis[0] = corner[1].subtract(corner[0]); axis[1] = corner[3].subtract(corner[0]); // Make the length of each axis 1/edge length so we know any // dot product must be less than 1 to fall within the edge. for (int a = 0; a < axis.length; ++a) { axis[a] = axis[a].divide((axis[a].length() * axis[a].length())); origin[a] = corner[0].dot(axis[a]); } } public void moveTo(Vector2D center) { Vector2D centroid = (corner[0].add(corner[1]).add(corner[2]).add(corner[3])).divide(4.0f); Vector2D translation = center.subtract(centroid); for (int c = 0; c < 4; ++c) { corner[c] = corner[c].add(translation); } computeAxes(); computeDimensions(center,angle); } // Returns true if the intersection of the boxes is non-empty. public boolean overlaps(OBB2D other) { if(right() < other.left()) { return false; } if(bottom() < other.top()) { return false; } if(left() > other.right()) { return false; } if(top() > other.bottom()) { return false; } if(other.getAngle() == 0.0f && getAngle() == 0.0f) { return true; } return overlaps1Way(other) && other.overlaps1Way(this); } public Vector2D getCenter() { return center; } public float getWidth() { return extents.x * 2; } public float getHeight() { return extents.y * 2; } public void setAngle(float angle) { set(center,getWidth(),getHeight(),angle); } public float getAngle() { return angle; } public void setSize(float w,float h) { set(center,w,h,angle); } public float left() { return boundingRect.left; } public float right() { return boundingRect.right; } public float bottom() { return boundingRect.bottom; } public float top() { return boundingRect.top; } public RectF getBoundingRect() { return boundingRect; } public boolean overlaps(float left, float top, float right, float bottom) { if(right() < left) { return false; } if(bottom() < top) { return false; } if(left() > right) { return false; } if(top() > bottom) { return false; } return true; } }; What I do is when I predict a hit on the car, I force it back. It does not work that well and seems like a bad idea. What could I do to have more proper collision resolution. Such that if I hit a wall I will never get stuck in it and if I hit the side of a wall I can steer my way out of it. Thanks I found this nice ppt. It talks about pulling objects apart and calculating new velocities. How could I calc new velocities in my case? http://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CC8QFjAB&url=http%3A%2F%2Fcoitweb.uncc.edu%2F~tbarnes2%2FGameDesignFall05%2FSlides%2FCh4.2-CollDet.ppt&ei=x4ucULy5M6-N0QGRy4D4Cg&usg=AFQjCNG7FVDXWRdLv8_-T5qnFyYld53cTQ&cad=rja

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  • SQL SERVER – Puzzle Involving NULL – Resolve – Error – Operand data type void type is invalid for sum operator

    - by pinaldave
    Today is Monday let us start this week with interesting puzzle. Yesterday I had also posted quick question here: SQL SERVER – T-SQL Scripts to Find Maximum between Two Numbers Run following code: SELECT SUM(data) FROM (SELECT NULL AS DATA) t It will throw following error. Msg 8117, Level 16, State 1, Line 1 Operand data type void type is invalid for sum operator. I can easily fix if I use ISNULL Function as displayed following. SELECT SUM(data) FROM (SELECT ISNULL(NULL,0) AS DATA) t Above script will not throw an error. However, there is one more method how this can be fixed. Can you come up with another method which will not generate error? Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Puzzle, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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  • Ingame menu is not working correctly

    - by Johnny
    The ingame menu opens when the player presses Escape during the main game. If the player presses Y in the ingame menu, the game switches to the main menu. Up to here, everything works. But: On the other hand, if the player presses N in the ingame menu, the game should switch back to the main game(should resume the main game). But that doesn't work. The game just rests in the ingame menu if the player presses N. I set a breakpoint in this line of the Ingamemenu class: KeyboardState kbState = Keyboard.GetState(); CurrentSate/currentGameState and LastState/lastGameState have the same state: IngamemenuState. But LastState/lastGameState should not have the same state than CurrentSate/currentGameState. What is wrong? Why is the ingame menu not working correctly? public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; IState lastState, currentState; public enum GameStates { IntroState = 0, MenuState = 1, MaingameState = 2, IngamemenuState = 3 } public void ChangeGameState(GameStates newState) { lastGameState = currentGameState; lastState = currentState; switch (newState) { case GameStates.IntroState: currentState = new Intro(this); currentGameState = GameStates.IntroState; break; case GameStates.MenuState: currentState = new Menu(this); currentGameState = GameStates.MenuState; break; case GameStates.MaingameState: currentState = new Maingame(this); currentGameState = GameStates.MaingameState; break; case GameStates.IngamemenuState: currentState = new Ingamemenu(this); currentGameState = GameStates.IngamemenuState; break; } currentState.Load(Content); } public void ChangeCurrentToLastGameState() { currentGameState = lastGameState; currentState = lastState; } public GameStates CurrentState { get { return currentGameState; } set { currentGameState = value; } } public GameStates LastState { get { return lastGameState; } set { lastGameState = value; } } private GameStates currentGameState = GameStates.IntroState; private GameStates lastGameState; public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; } protected override void Initialize() { ChangeGameState(GameStates.IntroState); base.Initialize(); } protected override void LoadContent() { spriteBatch = new SpriteBatch(GraphicsDevice); currentState.Load(Content); } protected override void Update(GameTime gameTime) { currentState.Update(gameTime); if ((lastGameState == GameStates.MaingameState) && (currentGameState == GameStates.IngamemenuState)) { lastState.Update(gameTime); } base.Update(gameTime); } protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); spriteBatch.Begin(); if ((lastGameState == GameStates.MaingameState) && (currentGameState == GameStates.IngamemenuState)) { lastState.Render(spriteBatch); } currentState.Render(spriteBatch); spriteBatch.End(); base.Draw(gameTime); } } public interface IState { void Load(ContentManager content); void Update(GameTime gametime); void Render(SpriteBatch batch); } public class Intro : IState { Texture2D Titelbildschirm; private Game1 game1; public Intro(Game1 game) { game1 = game; } public void Load(ContentManager content) { Titelbildschirm = content.Load<Texture2D>("gruft"); } public void Update(GameTime gametime) { KeyboardState kbState = Keyboard.GetState(); if (kbState.IsKeyDown(Keys.Space)) game1.ChangeGameState(Game1.GameStates.MenuState); } public void Render(SpriteBatch batch) { batch.Draw(Titelbildschirm, new Rectangle(0, 0, 1280, 720), Color.White); } } public class Menu:IState { Texture2D Choosescreen; private Game1 game1; public Menu(Game1 game) { game1 = game; } public void Load(ContentManager content) { Choosescreen = content.Load<Texture2D>("menubild"); } public void Update(GameTime gametime) { KeyboardState kbState = Keyboard.GetState(); if (kbState.IsKeyDown(Keys.Enter)) game1.ChangeGameState(Game1.GameStates.MaingameState); if (kbState.IsKeyDown(Keys.Escape)) game1.Exit(); } public void Render(SpriteBatch batch) { batch.Draw(Choosescreen, new Rectangle(0, 0, 1280, 720), Color.White); } } public class Maingame : IState { Texture2D Spielbildschirm, axe; Vector2 position = new Vector2(100,100); private Game1 game1; public Maingame(Game1 game) { game1 = game; } public void Load(ContentManager content) { Spielbildschirm = content.Load<Texture2D>("hauszombie"); axe = content.Load<Texture2D>("axxx"); } public void Update(GameTime gametime) { KeyboardState keyboardState = Keyboard.GetState(); float delta = (float)gametime.ElapsedGameTime.TotalSeconds; position.X += 5 * delta; position.Y += 3 * delta; if (keyboardState.IsKeyDown(Keys.Escape)) game1.ChangeGameState(Game1.GameStates.IngamemenuState); } public void Render(SpriteBatch batch) { batch.Draw(Spielbildschirm, new Rectangle(0, 0, 1280, 720), Color.White); batch.Draw(axe, position, Color.White); } } public class Ingamemenu : IState { Texture2D Quitscreen; private Game1 game1; public Ingamemenu(Game1 game) { game1 = game; } public void Load(ContentManager content) { Quitscreen = content.Load<Texture2D>("quit"); } public void Update(GameTime gametime) { KeyboardState kbState = Keyboard.GetState(); if (kbState.IsKeyDown(Keys.Y)) game1.ChangeGameState(Game1.GameStates.MenuState); if (kbState.IsKeyDown(Keys.N)) game1.ChangeCurrentToLastGameState(); } public void Render(SpriteBatch batch) { batch.Draw(Quitscreen, new Rectangle(200, 200, 200, 200), Color.White); } }

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  • Java Simple Calculator

    - by Lahiru Kavinda
    I have made this calculator program in Java. This works well only when two numbers are calculated at one time. That means to get the sum of 1+2+3 you have to go this way : press 1 press + press 2 press = press + press 3 press = and it calculates it as 6. But I want to program this so that I can get the answer by: press 1 press + press 2 press + press 3 press = but this gives the answer 5!!! How to code this so that it works like an ordinary calculator? Here is my code: import java.awt.*; import java.awt.event.*; import javax.swing.*; public class cal1 extends JFrame { double op1 = 0d, op2 = 0d; double result = 0d; char action; boolean b = false; boolean pressequal = false; public cal1() { makeUI(); } private void makeUI() { setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setSize(400, 400); b0 = new JButton("0"); b1 = new JButton("1"); b2 = new JButton("2"); b3 = new JButton("3"); b4 = new JButton("4"); b5 = new JButton("5"); b6 = new JButton("6"); b7 = new JButton("7"); b8 = new JButton("8"); b9 = new JButton("9"); bDot = new JButton("."); bMul = new JButton("*"); bDiv = new JButton("/"); bPlus = new JButton("+"); bMinus = new JButton("-"); bEq = new JButton("="); t = new JTextField(12); t.setFont(new Font("Tahoma", Font.PLAIN, 24)); t.setHorizontalAlignment(JTextField.RIGHT); numpad = new JPanel(); display = new JPanel(); numpad.add(b7); numpad.add(b8); numpad.add(b9); numpad.add(bMul); numpad.add(b4); numpad.add(b5); numpad.add(b6); numpad.add(bDiv); numpad.add(b1); numpad.add(b2); numpad.add(b3); numpad.add(bMinus); numpad.add(bDot); numpad.add(b0); numpad.add(bEq); numpad.add(bPlus); numpad.setLayout(new GridLayout(4, 5, 5, 4)); display.add(t); add(display, BorderLayout.NORTH); add(numpad, BorderLayout.CENTER); t.addKeyListener(new KeyAdapter() { @Override public void keyTyped(KeyEvent e) { typeOnt(e); } }); b0.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b0pressed(e); } }); b1.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b1pressed(e); } }); b2.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b2pressed(e); } }); b3.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b3pressed(e); } }); b4.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b4pressed(e); } }); b5.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b5pressed(e); } }); b6.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b6pressed(e); } }); b7.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b7pressed(e); } }); b8.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b8pressed(e); } }); b9.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { b9pressed(e); } }); bDot.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { bDotpressed(e); } }); bPlus.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { bPlusPressed(e); } }); bMinus.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { bMinusPressed(e); } }); bMul.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { bMulPressed(e); } }); bDiv.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { bDivPressed(e); } }); bEq.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { bEqpressed(e); } }); } void typeOnt(KeyEvent e) { e.consume(); } void b0pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "0"); } else { t.setText(t.getText() + "0"); } } void b1pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "1"); } else { t.setText(t.getText() + "1"); } } void b2pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "2"); } else { t.setText(t.getText() + "2"); } } void b3pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "3"); } else { t.setText(t.getText() + "3"); } } void b4pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "4"); } else { t.setText(t.getText() + "4"); } } void b5pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "5"); } else { t.setText(t.getText() + "5"); } } void b6pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "6"); } else { t.setText(t.getText() + "6"); } } void b7pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "7"); } else { t.setText(t.getText() + "7"); } } void b8pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "8"); } else { t.setText(t.getText() + "8"); } } void b9pressed(ActionEvent e) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "9"); } else { t.setText(t.getText() + "9"); } } void bDotpressed(ActionEvent e) { if (!t.getText().contains(".")) { if (b) { t.setText(null); b = false; t.setText(t.getText() + "0."); } else if (t.getText().isEmpty()) { t.setText("0."); } else { t.setText(t.getText() + "."); } } } void bPlusPressed(ActionEvent e) { b = true; action = '+'; op1 = Double.parseDouble(t.getText()); } void bMinusPressed(ActionEvent e) { b = true; action = '-'; op1 = Double.parseDouble(t.getText()); } void bMulPressed(ActionEvent e) { b = true; action = '*'; op1 = Double.parseDouble(t.getText()); } void bDivPressed(ActionEvent e) { b = true; action = '/'; op1 = Double.parseDouble(t.getText()); } void bEqpressed(ActionEvent e) { op2 = Double.parseDouble(t.getText()); doCal(); } void doCal() { switch (action) { case '+': result = op1 + op2; break; case '-': result = op1 - op2; break; case '*': result = op1 * op2; break; case '/': result = op1 / op2; break; } t.setText(String.valueOf(result)); } public static void main(String[] args) { new cal1().setVisible(true); } JButton b0; JButton b1; JButton b2; JButton b3; JButton b4; JButton b5; JButton b6; JButton b7; JButton b8; JButton b9; JButton bDot; JButton bPlus; JButton bMinus; JButton bMul; JButton bDiv; JButton bEq; JPanel display; JPanel numpad; JTextField t; }

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  • How to pass a function in a function?

    - by SoulBeaver
    That's an odd title. I would greatly appreciate it if somebody could clarify what exactly I'm asking because I'm not so sure myself. I'm watching the Stanford videos on Programming Paradigms(that teacher is awesome) and I'm up to video five when he started doing this: void *lSearch( void* key, void* base, int elemSize, int n, int (*cmpFn)(void*, void*)) Naturally, I thought to myself, "Oi, I didn't know you could declare a function and define it later!". So I created my own C++ test version. int foo(int (*bar)(void*, void*)); int bar(void* a, void* b); int main(int argc, char** argv) { int *func = 0; foo(bar); cin.get(); return 0; } int foo(int (*bar)(void*, void*)) { int c(10), d(15); int *a = &c; int *b = &d; bar(a, b); return 0; } int bar(void* a, void* b) { cout << "Why hello there." << endl; return 0; } The question about the code is this: it fails if I declare function int *bar as a parameter of foo, but not int (*bar). Why!? Also, the video confuses me in the fact that his lSearch definition void* lSearch( /*params*/ , int (*cmpFn)(void*, void*)) is calling cmpFn in the definition, but when calling the lSearch function lSearch( /*params*/, intCmp ); also calls the defined function int intCmp(void* elem1, void* elem2); and I don't get how that works. Why, in lSearch, is the function called cmpFn, but defined as intCmp, which is of type int, not int* and still works? And why does the function in lSearch not have to have defined parameters?

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  • C function prototype: void f(). Is it recommended?

    - by ycalleecharan
    Hi, I'm learning C and I saw in a book that a function prototype has the form void f() and in the function declaration or in the calling function, the f function takes arguments. Thus In the function declaration we have something like void f(long double y[], long double A) and in the calling function is f(y, A). The function is doing operations on the array y i.e. when the function is called, some elements in the array y are changing. A is just a constant numerical value that doesn't change. I have two questions: If defining the function prototype at the top in the program as void f() a good practice? Or is it better to put it as void f(long double y[], long double A) as in the function declaration? The called function f is changing elements in the array y. Is void the right return type? The program is working fine as such with the void as described. Or should I change all my "voids" to "long double". I'm working with long double as I need as much precision as possible though on my machine both double and long double gives me 15 precision digits. Thanks a lot

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  • functional, bind1st and mem_fun

    - by Neil G
    Why won't this compile? #include <functional> #include <boost/function.hpp> class A { A() { typedef boost::function<void ()> FunctionCall; FunctionCall f = std::bind1st(std::mem_fun(&A::process), this); } void process() {} }; Errors: In file included from /opt/local/include/gcc44/c++/bits/stl_function.h:712, from /opt/local/include/gcc44/c++/functional:50, from a.cc:1: /opt/local/include/gcc44/c++/backward/binders.h: In instantiation of 'std::binder1st<std::mem_fun_t<void, A> >': a.cc:7: instantiated from here /opt/local/include/gcc44/c++/backward/binders.h:100: error: no type named 'second_argument_type' in 'class std::mem_fun_t<void, A>' /opt/local/include/gcc44/c++/backward/binders.h:103: error: no type named 'first_argument_type' in 'class std::mem_fun_t<void, A>' /opt/local/include/gcc44/c++/backward/binders.h:106: error: no type named 'first_argument_type' in 'class std::mem_fun_t<void, A>' /opt/local/include/gcc44/c++/backward/binders.h:111: error: no type named 'second_argument_type' in 'class std::mem_fun_t<void, A>' /opt/local/include/gcc44/c++/backward/binders.h:117: error: no type named 'second_argument_type' in 'class std::mem_fun_t<void, A>' /opt/local/include/gcc44/c++/backward/binders.h: In function 'std::binder1st<_Operation> std::bind1st(const _Operation&, const _Tp&) [with _Operation = std::mem_fun_t<void, A>, _Tp = A*]': a.cc:7: instantiated from here /opt/local/include/gcc44/c++/backward/binders.h:126: error: no type named 'first_argument_type' in 'class std::mem_fun_t<void, A>' In file included from /opt/local/include/boost/function/detail/maybe_include.hpp:13, from /opt/local/include/boost/function/detail/function_iterate.hpp:14, from /opt/local/include/boost/preprocessor/iteration/detail/iter/forward1.hpp:47, from /opt/local/include/boost/function.hpp:64, from a.cc:2: /opt/local/include/boost/function/function_template.hpp: In static member function 'static void boost::detail::function::void_function_obj_invoker0<FunctionObj, R>::invoke(boost::detail::function::function_buffer&) [with FunctionObj = std::binder1st<std::mem_fun_t<void, A> >, R = void]': /opt/local/include/boost/function/function_template.hpp:913: instantiated from 'void boost::function0<R>::assign_to(Functor) [with Functor = std::binder1st<std::mem_fun_t<void, A> >, R = void]' /opt/local/include/boost/function/function_template.hpp:722: instantiated from 'boost::function0<R>::function0(Functor, typename boost::enable_if_c<boost::type_traits::ice_not::value, int>::type) [with Functor = std::binder1st<std::mem_fun_t<void, A> >, R = void]' /opt/local/include/boost/function/function_template.hpp:1064: instantiated from 'boost::function<R()>::function(Functor, typename boost::enable_if_c<boost::type_traits::ice_not::value, int>::type) [with Functor = std::binder1st<std::mem_fun_t<void, A> >, R = void]' a.cc:7: instantiated from here /opt/local/include/boost/function/function_template.hpp:153: error: no match for call to '(std::binder1st<std::mem_fun_t<void, A> >) ()'

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  • Jdbc - Connect remote Mysql Database error

    - by Guilherme Ruiz
    I'm using JDBC to connect my program to a MySQL database. I already put the port number and yes, my database have permission to access. When i use localhost work perfectly, but when i try connect to a remote MySQL database, show this error on console. java.lang.ExceptionInInitializerError Caused by: java.lang.NumberFormatException: null at java.lang.Integer.parseInt(Integer.java:454) at java.lang.Integer.parseInt(Integer.java:527) at serial.BDArduino.<clinit>(BDArduino.java:25) Exception in thread "main" Java Result: 1 CONSTRUÍDO COM SUCESSO (tempo total: 1 segundo) Thank you in Advance ! MAIN CODE /* * To change this template, choose Tools | Templates * and open the template in the editor. */ package serial; import gnu.io.CommPort; import gnu.io.CommPortIdentifier; import gnu.io.SerialPort; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import javax.swing.JFrame; import javax.swing.JOptionPane; /** * * @author Ruiz */ public class BDArduino extends JFrame { static boolean connected = false; static int aux_sql8 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin8")); static int aux_sql2 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin2")); CommPort commPort = null; SerialPort serialPort = null; InputStream inputStream = null; static OutputStream outputStream = null; String comPortNum = "COM10"; int baudRate = 9600; int[] intArray = {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13}; /** * Creates new form ArduinoTest */ public BDArduino() { //super("Arduino Test App"); initComponents(); } class Escrita extends Thread { private int i; public void run() { while (true) { System.out.println("Número :" + i++); } } } //public void actionPerformed(ActionEvent e) { // String arg = e.getActionCommand(); public static void writeData(int a) throws IOException { outputStream.write(a); } public void action(String arg) { System.out.println(arg); Object[] msg = {"Baud Rate: ", "9600", "COM Port #: ", "COM10"}; if (arg == "connect") { if (connected == false) { new BDArduino.ConnectionMaker().start(); } else { closeConnection(); } } if (arg == "disconnect") { serialPort.close(); closeConnection(); } if (arg == "p2") { System.out.print("Pin #2\n"); try { outputStream.write(intArray[0]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p3") { System.out.print("Pin #3\n"); try { outputStream.write(intArray[1]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p4") { System.out.print("Pin #4\n"); try { outputStream.write(intArray[2]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p5") { System.out.print("Pin #5\n"); try { outputStream.write(intArray[3]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p6") { System.out.print("Pin #6\n"); try { outputStream.write(intArray[4]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p7") { System.out.print("Pin #7\n"); try { outputStream.write(intArray[5]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p8") { System.out.print("Pin #8\n"); try { outputStream.write(intArray[6]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p9") { System.out.print("Pin #9\n"); try { outputStream.write(intArray[7]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p10") { System.out.print("Pin #10\n"); try { outputStream.write(intArray[8]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p11") { System.out.print("Pin #11\n"); try { outputStream.write(intArray[9]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p12") { System.out.print("Pin #12\n"); try { outputStream.write(intArray[10]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p13") { System.out.print("Pin #12\n"); try { outputStream.write(intArray[11]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } } //******************************************************* //Arduino Connection *************************************** //****************************************************** void closeConnection() { try { outputStream.close(); } catch (Exception ex) { ex.printStackTrace(); String cantCloseConnectionMessage = "Can't Close Connection!"; JOptionPane.showMessageDialog(null, cantCloseConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } connected = false; System.out.print("\nDesconectado\n"); String disconnectedConnectionMessage = "Desconectado!"; JOptionPane.showMessageDialog(null, disconnectedConnectionMessage, "Desconectado", JOptionPane.INFORMATION_MESSAGE); }//end closeConnection() void connect() throws Exception { String portName = comPortNum; CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName); if (portIdentifier.isCurrentlyOwned()) { System.out.println("Error: Port is currently in use"); String portInUseConnectionMessage = "Port is currently in use!\nTry Again Later..."; JOptionPane.showMessageDialog(null, portInUseConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } else { commPort = portIdentifier.open(this.getClass().getName(), 2000); if (commPort instanceof SerialPort) { serialPort = (SerialPort) commPort; serialPort.setSerialPortParams(baudRate, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE); outputStream = serialPort.getOutputStream(); } else { System.out.println("Error: Only serial ports are handled "); String onlySerialConnectionMessage = "Serial Ports ONLY!"; JOptionPane.showMessageDialog(null, onlySerialConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } }//end else //wait some time try { Thread.sleep(300); } catch (InterruptedException ie) { } }//end connect //******************************************************* //*innerclasses****************************************** //******************************************************* public class ConnectionMaker extends Thread { public void run() { //try to make a connection try { connect(); } catch (Exception ex) { ex.printStackTrace(); System.out.print("ERROR: Cannot connect!"); String cantConnectConnectionMessage = "Cannot Connect!\nCheck the connection settings\nand/or your configuration\nand try again!"; JOptionPane.showMessageDialog(null, cantConnectConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } //show status serialPort.notifyOnDataAvailable(true); connected = true; //send ack System.out.print("\nConnected\n"); String connectedConnectionMessage = "Conectado!"; JOptionPane.showMessageDialog(null, connectedConnectionMessage, "Conectado", JOptionPane.INFORMATION_MESSAGE); }//end run }//end ConnectionMaker /** * This method is called from within the constructor to initialize the form. * WARNING: Do NOT modify this code. The content of this method is always * regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // <editor-fold defaultstate="collapsed" desc="Generated Code"> private void initComponents() { btnp2 = new javax.swing.JButton(); btncon = new javax.swing.JButton(); btndesc = new javax.swing.JButton(); btnp3 = new javax.swing.JButton(); btnp4 = new javax.swing.JButton(); btnp5 = new javax.swing.JButton(); btnp9 = new javax.swing.JButton(); btnp6 = new javax.swing.JButton(); btnp7 = new javax.swing.JButton(); btnp8 = new javax.swing.JButton(); btn13 = new javax.swing.JButton(); btnp10 = new javax.swing.JButton(); btnp11 = new javax.swing.JButton(); btnp12 = new javax.swing.JButton(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); btnp2.setText("2"); btnp2.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp2MouseClicked(evt); } }); btncon.setText("Conectar"); btncon.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnconMouseClicked(evt); } }); btndesc.setText("Desconectar"); btndesc.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btndescMouseClicked(evt); } }); btnp3.setText("3"); btnp3.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp3MouseClicked(evt); } }); btnp4.setText("4"); btnp4.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp4MouseClicked(evt); } }); btnp5.setText("5"); btnp5.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp5MouseClicked(evt); } }); btnp9.setText("9"); btnp9.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp9MouseClicked(evt); } }); btnp6.setText("6"); btnp6.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp6MouseClicked(evt); } }); btnp7.setText("7"); btnp7.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp7MouseClicked(evt); } }); btnp8.setText("8"); btnp8.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp8MouseClicked(evt); } }); btn13.setText("13"); btn13.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btn13MouseClicked(evt); } }); btnp10.setText("10"); btnp10.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp10MouseClicked(evt); } }); btnp11.setText("11"); btnp11.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp11MouseClicked(evt); } }); btnp12.setText("12"); btnp12.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp12MouseClicked(evt); } }); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(20, 20, 20) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false) .addGroup(layout.createSequentialGroup() .addComponent(btncon) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) .addComponent(btndesc)) .addGroup(layout.createSequentialGroup() .addComponent(btnp6, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp7, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp8, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp9, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGroup(layout.createSequentialGroup() .addComponent(btnp10, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp11, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp12, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btn13, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGroup(layout.createSequentialGroup() .addComponent(btnp2, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp3, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp4, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp5, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))) .addContainerGap(20, Short.MAX_VALUE)) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addContainerGap() .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(btncon) .addComponent(btndesc)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 20, Short.MAX_VALUE) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(btnp2) .addComponent(btnp3) .addComponent(btnp4) .addComponent(btnp5)) .addGap(18, 18, 18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(btnp6) .addComponent(btnp7) .addComponent(btnp8) .addComponent(btnp9)) .addGap(18, 18, 18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(btnp10) .addComponent(btnp11) .addComponent(btnp12) .addComponent(btn13)) .addGap(22, 22, 22)) ); pack(); }// </editor-fold> private void btnp2MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p2"); } private void btnconMouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("connect"); } private void btndescMouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("disconnect"); } private void btnp3MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p3"); } private void btnp4MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p4"); } private void btnp5MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here action("p5"); } private void btnp9MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p9"); } private void btnp6MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p6"); } private void btnp7MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p7"); } private void btnp8MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p8"); } private void btn13MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p13"); } private void btnp10MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p10"); } private void btnp11MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p11"); } private void btnp12MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p12"); } /** * @param args the command line arguments */ public static void main(String args[]) throws IOException { /* Set the Nimbus look and feel */ //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) "> /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel. * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) { if ("Nimbus".equals(info.getName())) { javax.swing.UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (Exception e) { } //</editor-fold> /* Create and display the form */ java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new BDArduino().setVisible(true); } }); //} while (true) { // int sql8 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin8")); if (connected == true && sql8 != aux_sql8) { aux_sql8 = sql8; if(sql8 == 1){ writeData(2); }else{ writeData(3); } } int sql2 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin2")); if (connected == true && sql2 != aux_sql2) { aux_sql2 = sql2; if(sql2 == 1){ writeData(4); }else{ writeData(5); } } try { Thread.sleep(500); } catch (InterruptedException e) { e.printStackTrace(); } } } // Variables declaration - do not modify private javax.swing.JButton btn13; private javax.swing.JButton btncon; private javax.swing.JButton btndesc; private javax.swing.JButton btnp10; private javax.swing.JButton btnp11; private javax.swing.JButton btnp12; private javax.swing.JButton btnp2; private javax.swing.JButton btnp3; private javax.swing.JButton btnp4; private javax.swing.JButton btnp5; private javax.swing.JButton btnp6; private javax.swing.JButton btnp7; private javax.swing.JButton btnp8; private javax.swing.JButton btnp9; // End of variables declaration }

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