Search Results

Search found 21199 results on 848 pages for 'game controller'.

Page 377/848 | < Previous Page | 373 374 375 376 377 378 379 380 381 382 383 384  | Next Page >

  • Finding direction of travel in a world with wrapped edges

    - by crazy
    I need to find the shortest distance direction from one point in my 2D world to another point where the edges are wrapped (like asteroids etc). I know how to find the shortest distance but am struggling to find which direction it's in. The shortest distance is given by: int rows = MapY; int cols = MapX; int d1 = abs(S.Y - T.Y); int d2 = abs(S.X - T.X); int dr = min(d1, rows-d1); int dc = min(d2, cols-d2); double dist = sqrt((double)(dr*dr + dc*dc)); Example of the world : : T : :--------------:--------- : : : S : : : : : : T : : : :--------------: In the diagram the edges are shown with : and -. I've shown a wrapped repeat of the world at the top right too. I want to find the direction in degrees from S to T. So the shortest distance is to the top right repeat of T. but how do I calculate the direction in degreed from S to the repeated T in the top right? I know the positions of both S and T but I suppose I need to find the position of the repeated T however there more than 1. The worlds coordinates system starts at 0,0 at the top left and 0 degrees for the direction could start at West. It seems like this shouldn’t be too hard but I haven’t been able to work out a solution. I hope somone can help? Any websites would be appreciated.

    Read the article

  • Ray Tracing concers: Efficient Data Structure and Photon Mapping

    - by Grieverheart
    I'm trying to build a simple ray tracer for specific target scenes. An example of such scene can be seen below. I'm concerned as to what accelerating data structure would be most efficient in this case since all objects are touching but on the other hand, the scene is uniform. The objects in my ray tracer are stored as a collection of triangles, thus I also have access to individual triangles. Also, when trying to find the bounding box of the scene, how should infinite planes be handled? Should one instead use the viewing frustum to calculate the bounding box? A few other questions I have are about photon mapping. I've read the original paper by Jensen and many more material. In the compact data structure for the photon they introduce, they store photon power as 4 chars, which from my understanding is 3 chars for color and 1 for flux. But I don't understand how 1 char is enough to store a flux of the order of 1/n, where n is the number of photons (I'm also a bit confused about flux vs power). The other question about photon mapping is, if it would be more efficient in my case to store photons per object (or even per Object's triangle) instead of using a balanced kd-tree. Also, same question about bounding box of the scene but for photon mapping. How should one find a bounding box from the pov of the light when infinite planes are involved?

    Read the article

  • Lock mouse in center of screen, and still use to move camera Unity

    - by Flotolk
    I am making a program from 1st person point of view. I would like the camera to be moved using the mouse, preferably using simple code, like from XNA var center = this.Window.ClientBounds; MouseState newState = Mouse.GetState(); if (Keyboard.GetState().IsKeyUp(Keys.Escape)) { Mouse.SetPosition((int)center.X, (int)center.Y); camera.Rotation -= (newState.X - center.X) * 0.005f; camera.UpDown += (newState.Y - center.Y) * 0.005f; } Is there any code that lets me do this in Unity, since Unity does not support XNA, I need a new library to use, and a new way to collect this input. this is also a little tougher, since I want one object to go up and down based on if you move it the mouse up and down, and another object to be the one turning left and right. I am also very concerned about clamping the mouse to the center of the screen, since you will be selecting items, and it is easiest to have a simple cross-hairs in the center of the screen for this purpose. Here is the code I am using to move right now: using UnityEngine; using System.Collections; [AddComponentMenu("Camera-Control/Mouse Look")] public class MouseLook : MonoBehaviour { public enum RotationAxes { MouseXAndY = 0, MouseX = 1, MouseY = 2 } public RotationAxes axes = RotationAxes.MouseXAndY; public float sensitivityX = 15F; public float sensitivityY = 15F; public float minimumX = -360F; public float maximumX = 360F; public float minimumY = -60F; public float maximumY = 60F; float rotationY = 0F; void Update () { if (axes == RotationAxes.MouseXAndY) { float rotationX = transform.localEulerAngles.y + Input.GetAxis("Mouse X") * sensitivityX; rotationY += Input.GetAxis("Mouse Y") * sensitivityY; rotationY = Mathf.Clamp (rotationY, minimumY, maximumY); transform.localEulerAngles = new Vector3(-rotationY, rotationX, 0); } else if (axes == RotationAxes.MouseX) { transform.Rotate(0, Input.GetAxis("Mouse X") * sensitivityX, 0); } else { rotationY += Input.GetAxis("Mouse Y") * sensitivityY; rotationY = Mathf.Clamp (rotationY, minimumY, maximumY); transform.localEulerAngles = new Vector3(-rotationY, transform.localEulerAngles.y, 0); } while (Input.GetKeyDown(KeyCode.Space) == true) { Screen.lockCursor = true; } } void Start () { // Make the rigid body not change rotation if (GetComponent<Rigidbody>()) GetComponent<Rigidbody>().freezeRotation = true; } } This code does everything except lock the mouse to the center of the screen. Screen.lockCursor = true; does not work though, since then the camera no longer moves, and the cursor does not allow you to click anything else either.

    Read the article

  • Is there a way to export all the images of my tweening effect in Flash?

    - by Paul
    i'm using Flash to create the animation of my character in 2D (i'm just beginning). Is it possible to make a tween effect of a character, and then automatically export all the images/frames? So far, it's a bit fastidious : i create my tweening effect, then i put a keyframe for each frame i want to copy and paste, then i select the movieclips and shapes and copy and paste them into another flash document, i position those clips at the exact same location as the previous image, then i erase the previous image and export the image... For 30 frames! Is there any faster way? Thanks

    Read the article

  • getting bone base and tip positions from a transform matrix?

    - by ddos
    I need this for a Blender3d script, but you don't really need to know Blender to answer this. I need to get bone head and tip positions from a transform matrix read from a file. The position of base is the location part of the matrix, length of the bone (distance from base to tip) is the scale, position of the tip is calculated from the scale (distance from bone base) and rotation part of the matrix. So how to calculate these? bone.base([x,y,z]) # x,y,z - floats bone.tip([x,y,z])

    Read the article

  • 2d Ice movement

    - by Jeremy Clarkson
    I am building an top-down 2d RPG like zelda. I have been trying to implement ice sliding. I have a tile with the slide property. I thought it would be easy to get working. I figured that I would read the slide property, and move the character forward until the slide property no longer exists. So I tried a loop but all it did was stop at the first tile in an infinite loop. I then took the loop out and tried taking direct control of the character to move him along the slide path but I couldn't get it to move. Is there an easy way to do an ice sliding tile based movement in libgdx. I looked for a tutorial but none exist.

    Read the article

  • Efficiently representing a dynamic transform hierarchy

    - by Mattia
    I'm looking for a way to represent a dynamic transform hierarchy (i.e. one where nodes can be inserted and removed arbitrarily) that's a bit more efficient than using a standard tree of pointers . I saw the answers to this question ( Efficient structure for representing a transform hierarchy. ), but as far as I can determine the tree-as-array approach only works for static hierarchies or dynamic ones where nodes have a fixed number of children (both deal-breakers for me). I'm probably wrong about that but could anyone point out how? If I'm not wrong are there other alternatives that work for dynamic hierarchies?

    Read the article

  • How to get warnings when compiling fx files

    - by jdv-Jan de Vaan
    When I compile DirectX shaders (.fx files), I dont see any compiler warnings unless there was an error in the effect. This happens both when using the offline FXC compiler, as well as calling SlimDx's CompileEffect (which is what we normally do). I could force warnings as errors (/WX), but if you enable that, you get an error that compilation failed, without the warning that caused the problem. So how can I output warnings for shaders that compile properly?

    Read the article

  • How can I downsample a texture using FBOs?

    - by snape
    I am rendering a scene to FBO as my render target whose size is 8 times the size of the orignal screen in OpenGL. Now i wan to downsample the texture generated by FBO to the size of the screen so as to achieve spatial anti aliasing. How do i achieve the down sampling ? Please provide implementation details. Note : If there is a better way of doing anti aliasing in FBOs please mention that too. I am trying to remove the aliasing in the image attached below.

    Read the article

  • OpenGL position from depth is wrong

    - by CoffeeandCode
    My engine is currently implemented using a deferred rendering technique, and today I decided to change it up a bit. First I was storing 5 textures as so: DEPTH24_STENCIL8 - Depth and stencil RGBA32F - Position RGBA10_A2 - Normals RGBA8 x 2 - Specular & Diffuse I decided to minimize it and reconstruct positions from the depth buffer. Trying to figure out what is wrong with my method currently has not been fun :/ Currently I get this: which changes whenever I move the camera... weird Vertex shader really simple #version 150 layout(location = 0) in vec3 position; layout(location = 1) in vec2 uv; out vec2 uv_f; void main(){ uv_f = uv; gl_Position = vec4(position, 1.0); } Fragment shader Where the fun (and not so fun) stuff happens #version 150 uniform sampler2D depth_tex; uniform sampler2D normal_tex; uniform sampler2D diffuse_tex; uniform sampler2D specular_tex; uniform mat4 inv_proj_mat; uniform vec2 nearz_farz; in vec2 uv_f; ... other uniforms and such ... layout(location = 3) out vec4 PostProcess; vec3 reconstruct_pos(){ float z = texture(depth_tex, uv_f).x; vec4 sPos = vec4(uv_f * 2.0 - 1.0, z, 1.0); sPos = inv_proj_mat * sPos; return (sPos.xyz / sPos.w); } void main(){ vec3 pos = reconstruct_pos(); vec3 normal = texture(normal_tex, uv_f).rgb; vec3 diffuse = texture(diffuse_tex, uv_f).rgb; vec4 specular = texture(specular_tex, uv_f); ... do lighting ... PostProcess = vec4(pos, 1.0); // Just for testing } Rendering code probably nothing wrong here, seeing as though it always worked before this->gbuffer->bind(); gl::Clear(gl::COLOR_BUFFER_BIT | gl::DEPTH_BUFFER_BIT); gl::Enable(gl::DEPTH_TEST); gl::Enable(gl::CULL_FACE); ... bind geometry shader and draw models and shiz ... gl::Disable(gl::DEPTH_TEST); gl::Disable(gl::CULL_FACE); gl::Enable(gl::BLEND); ... bind textures and lighting shaders shown above then draw each light ... gl::BindFramebuffer(gl::FRAMEBUFFER, 0); gl::Clear(gl::COLOR_BUFFER_BIT | gl::DEPTH_BUFFER_BIT); gl::Disable(gl::BLEND); ... bind screen shaders and draw quad with PostProcess texture ... Rinse_and_repeat(); // not actually a function ;) Why are my positions being output like they are?

    Read the article

  • Creating a curved mesh on inside of sphere based on texture image coordinates

    - by user5025
    In Blender, I have created a sphere with a panoramic texture on the inside. I have also manually created a plane mesh (curved to match the size of the sphere) that sits on the inside wall where I can draw a different texture. This is great, but I really want to reduce the manual labor, and do some of this work in a script -- like having a variable for the panoramic image, and coordinates of the area in the photograph that I want to replace with a new mesh. The hardest part of doing this is going to be creating a curved mesh in code that can sit on the inside wall of a sphere. Can anyone point me in the right direction?

    Read the article

  • Zelda-style Top-down RPG. Storing data for each tile type

    - by Delerat
    I'm creating a Zelda-style RPG using Tiled, C#, and MonoGame. When my code parses the .tmx file, it will get a number to associate with each tile type based off of their position in the tile sheet. If I ever need to change my sprite sheet, this number will change for many of the tiles. How can I guarantee that when I parse my .tmx file, I will be able to know exactly what tile type I'm getting so that I can associate the proper data with it(transparency, animated, collision, etc.)?

    Read the article

  • How can I transform a Point2f with a matrix on Android?

    - by Vivendi
    I'm developing for Android and I'm using the android.renderscript.Matrix3f class to do some calculations. What I need to do now is to now is to do something like mat.tranform(pointIn, pointOut); So I need to transform a matrix by a given Point class. In awt I would simply do this: AffineTransform t = new AffineTransform(); Point2D.Float p = new Point2D.Float(); t.transform( p, p ); But in Android I now have this: Matrix3f t = new Matrix3f(); PointF p = new PointF(); // Now I need to tranform it somehow.. But the Matrix3f class in Android doesn't have a Matrix.transform(Point2D ptSrc, Point2D ptDst) method. So I guess I have to do the transformation manually. But I'm not really sure how that works. From what I've seen it's something like a translate and then a rotate? Could anyone please tell me how to do this in code?

    Read the article

  • How can I determine if a cube is adjacent to another cube, and optimize its buffers if so?

    - by Christian Frantz
    I'm trying to optimize the rendering of a collection of cubes, (based on an answer I was given to another question I asked). I understand the logic behind occlusion culling, but I'm having trouble with the code. When I create a cube, I want to determine if that cube is touching another existing cube, and if so I don't want to generate the redundant data in my vertex or index buffers. I'm planning on making a method that I call from my cube constructor so that everytime I create a cube, these checks are made, and neither occluded face is ever drawn. How would I go about this?

    Read the article

  • How do I increase moving speed of body?

    - by Siddharth
    How to move ball speedily on the screen using box2d in libGDX? package com.badlogic.box2ddemo; import com.badlogic.gdx.ApplicationListener; import com.badlogic.gdx.Gdx; import com.badlogic.gdx.graphics.GL10; import com.badlogic.gdx.graphics.Texture; import com.badlogic.gdx.graphics.g2d.Sprite; import com.badlogic.gdx.graphics.g2d.SpriteBatch; import com.badlogic.gdx.graphics.g2d.TextureRegion; import com.badlogic.gdx.math.Matrix4; import com.badlogic.gdx.math.Vector2; import com.badlogic.gdx.physics.box2d.Body; import com.badlogic.gdx.physics.box2d.BodyDef; import com.badlogic.gdx.physics.box2d.BodyDef.BodyType; import com.badlogic.gdx.physics.box2d.Box2DDebugRenderer; import com.badlogic.gdx.physics.box2d.CircleShape; import com.badlogic.gdx.physics.box2d.Fixture; import com.badlogic.gdx.physics.box2d.FixtureDef; import com.badlogic.gdx.physics.box2d.PolygonShape; import com.badlogic.gdx.physics.box2d.World; public class Box2DDemo implements ApplicationListener { private SpriteBatch batch; private TextureRegion texture; private World world; private Body groundDownBody, groundUpBody, groundLeftBody, groundRightBody, ballBody; private BodyDef groundBodyDef1, groundBodyDef2, groundBodyDef3, groundBodyDef4, ballBodyDef; private PolygonShape groundDownPoly, groundUpPoly, groundLeftPoly, groundRightPoly; private CircleShape ballPoly; private Sprite sprite; private FixtureDef fixtureDef; private Vector2 ballPosition; private Box2DDebugRenderer renderer; Vector2 vector2; @Override public void create() { texture = new TextureRegion(new Texture( Gdx.files.internal("img/red_ring.png"))); sprite = new Sprite(texture); sprite.setOrigin(sprite.getWidth() / 2, sprite.getHeight() / 2); batch = new SpriteBatch(); world = new World(new Vector2(0.0f, 0.0f), false); groundBodyDef1 = new BodyDef(); groundBodyDef1.type = BodyType.StaticBody; groundBodyDef1.position.x = 0.0f; groundBodyDef1.position.y = 0.0f; groundDownBody = world.createBody(groundBodyDef1); groundBodyDef2 = new BodyDef(); groundBodyDef2.type = BodyType.StaticBody; groundBodyDef2.position.x = 0f; groundBodyDef2.position.y = Gdx.graphics.getHeight(); groundUpBody = world.createBody(groundBodyDef2); groundBodyDef3 = new BodyDef(); groundBodyDef3.type = BodyType.StaticBody; groundBodyDef3.position.x = 0f; groundBodyDef3.position.y = 0f; groundLeftBody = world.createBody(groundBodyDef3); groundBodyDef4 = new BodyDef(); groundBodyDef4.type = BodyType.StaticBody; groundBodyDef4.position.x = Gdx.graphics.getWidth(); groundBodyDef4.position.y = 0f; groundRightBody = world.createBody(groundBodyDef4); groundDownPoly = new PolygonShape(); groundDownPoly.setAsBox(480.0f, 10f); fixtureDef = new FixtureDef(); fixtureDef.density = 0f; fixtureDef.restitution = 1f; fixtureDef.friction = 0f; fixtureDef.shape = groundDownPoly; fixtureDef.filter.groupIndex = 0; groundDownBody.createFixture(fixtureDef); groundUpPoly = new PolygonShape(); groundUpPoly.setAsBox(480.0f, 10f); fixtureDef = new FixtureDef(); fixtureDef.friction = 0f; fixtureDef.restitution = 0f; fixtureDef.density = 0f; fixtureDef.shape = groundUpPoly; fixtureDef.filter.groupIndex = 0; groundUpBody.createFixture(fixtureDef); groundLeftPoly = new PolygonShape(); groundLeftPoly.setAsBox(10f, 320f); fixtureDef = new FixtureDef(); fixtureDef.friction = 0f; fixtureDef.restitution = 0f; fixtureDef.density = 0f; fixtureDef.shape = groundLeftPoly; fixtureDef.filter.groupIndex = 0; groundLeftBody.createFixture(fixtureDef); groundRightPoly = new PolygonShape(); groundRightPoly.setAsBox(10f, 320f); fixtureDef = new FixtureDef(); fixtureDef.friction = 0f; fixtureDef.restitution = 0f; fixtureDef.density = 0f; fixtureDef.shape = groundRightPoly; fixtureDef.filter.groupIndex = 0; groundRightBody.createFixture(fixtureDef); ballPoly = new CircleShape(); ballPoly.setRadius(16f); fixtureDef = new FixtureDef(); fixtureDef.shape = ballPoly; fixtureDef.density = 1f; fixtureDef.friction = 1f; fixtureDef.restitution = 1f; ballBodyDef = new BodyDef(); ballBodyDef.type = BodyType.DynamicBody; ballBodyDef.position.x = (int) 200; ballBodyDef.position.y = (int) 200; ballBody = world.createBody(ballBodyDef); ballBody.setLinearVelocity(200f, 200f); // ballBody.applyLinearImpulse(new Vector2(250f, 250f), // ballBody.getLocalCenter()); ballBody.createFixture(fixtureDef); renderer = new Box2DDebugRenderer(true, false, false); } @Override public void dispose() { ballPoly.dispose(); groundLeftPoly.dispose(); groundUpPoly.dispose(); groundDownPoly.dispose(); groundRightPoly.dispose(); world.destroyBody(ballBody); world.dispose(); } @Override public void pause() { } @Override public void render() { world.step(1f/30f, 3, 3); Gdx.gl.glClearColor(1f, 1f, 1f, 1f); Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT); batch.begin(); vector2 = ballBody.getLinearVelocity(); System.out.println("X=" + vector2.x + " Y=" + vector2.y); ballPosition = ballBody.getPosition(); renderer.render(world,batch.getProjectionMatrix()); // int preX = (int) (vector2.x / Math.abs(vector2.x)); // int preY = (int) (vector2.y / Math.abs(vector2.y)); // // if (Math.abs(vector2.x) == 0.0f) // ballBody1.setLinearVelocity(1.4142137f, vector2.y); // else if (Math.abs(vector2.x) < 1.4142137f) // ballBody1.setLinearVelocity(preX * 5, vector2.y); // // if (Math.abs(vector2.y) == 0.0f) // ballBody1.setLinearVelocity(vector2.x, 1.4142137f); // else if (Math.abs(vector2.y) < 1.4142137f) // ballBody1.setLinearVelocity(vector2.x, preY * 5); batch.draw(sprite, (ballPosition.x - (texture.getRegionWidth() / 2)), (ballPosition.y - (texture.getRegionHeight() / 2))); batch.end(); } @Override public void resize(int arg0, int arg1) { } @Override public void resume() { } } I implement above code but I can not achieve higher moving speed of the ball

    Read the article

  • WIn API Basic Paint program

    - by Tom Burman
    Just trying to learn a bit of Win API. Im trying to make a basic drawing app, a bit like MS Paint. For the time being im trying to get one function to work which is, when you left click and drag the mouse around the screen a line is drawn behind the mouse. Heres what i have so far, but for some reason: 1) the line starts drawing straight away rather then waiting for the left click 2) the line isn't solid its very dotty. case WM_MOUSEMOVE: { if(MK_LBUTTON){ hdc = GetDC(hwnd); hPen = CreatePen(PS_SOLID,5,RGB(0, 0, 255)); SelectObject(hdc, hPen); int x = LOWORD(lParam); int y = HIWORD(lParam); MoveToEx(hdc,x,y,NULL); LineTo(hdc, LOWORD(lParam), HIWORD(lParam)); ReleaseDC(hwnd,hdc); } else break; } } Thanks for any help!

    Read the article

  • Safe zone implementation in Asteroids

    - by Moaz
    I would like to implement a safe zone for asteroids so that when the ship gets destroyed, it shouldn't be there unless it is safe from other asteroids. I tried to check the distance between each asteroid and the ship, and if it is above threshold, it sets a flag to the ship that's a safe zone, but sometimes it work and sometimes it doesn't. What am I doing wrong? Here's my code: for (list<Asteroid>::iterator itr_astroid = asteroids.begin(); itr_astroid!=asteroids.end(); ) { if(currentShip.m_state == Ship::Ship_Dead) { float distance = itr_astroid->getCenter().distance(Vec2f(getWindowWidth()/2,getWindowHeight()/2)); if( distance>200) { currentShip.m_saveField = true; break; } else { currentShip.m_saveField = false; itr_astroid++; } } else { itr_astroid++; } } At ship's death: if(m_state == Ship_Dead && m_saveField==true) { --m_lifeSpan; } if(m_lifeSpan<=0 && m_saveField == true) { m_state = Ship_Alive; m_Vel = Vec2f(0,0); m_Pos.x = app::getWindowWidth()/2; m_Pos.y = app::getWindowHeight()/2; m_lifeSpan = 100; }

    Read the article

  • Where can I find free or buy "next-gen" 3D Assets?

    - by Valmond
    Usually I buy 3D Assets from sites like turbosquid.com or similar. My problem is that I have lately implemented glow, normal maps, specular (and specular power) maps and reflection maps and I can't find any models that use those techniques. So where can I find / buy "next gen" assets (at least models/items with a normal map)? I have checked for similar posts but those I found are about either free only or 2D or 'ordinary' 3D so I hope this is not a duplicate.

    Read the article

  • Can't get sprite to rotate correctly?

    - by rphello101
    I'm attempting to play with graphics using Java/Slick 2d. I'm trying to get my sprite to rotate to wherever the mouse is on the screen and then move accordingly. I figured the best way to do this was to keep track of the angle the sprite is at since I have to multiply the cosine/sine of the angle by the move speed in order to get the sprite to go "forwards" even if it is, say, facing 45 degrees in quadrant 3. However, before I even worry about that, I'm having trouble even getting my sprite to rotate in the first place. Preliminary console tests showed that this code worked, but when applied to the sprite, it just kind twitches. Anyone know what's wrong? int mX = Mouse.getX(); int mY = HEIGHT - Mouse.getY(); int pX = sprite.x; int pY = sprite.y; int tempY, tempX; double mAng, pAng = sprite.angle; double angRotate=0; if(mX!=pX){ tempY=pY-mY; tempX=mX-pX; mAng = Math.toDegrees(Math.atan2(Math.abs((tempY)),Math.abs((tempX)))); if(mAng==0 && mX<=pX) mAng=180; } else{ if(mY>pY) mAng=270; else mAng=90; } //Calculations if(mX<pX&&mY<pY){ //If in Q2 mAng = 180-mAng; } if(mX<pX&&mY>pY){ //If in Q3 mAng = 180+mAng; } if(mX>pX&&mY>pY){ //If in Q4 mAng = 360-mAng; } angRotate = mAng-pAng; sprite.angle = mAng; sprite.image.setRotation((float)angRotate);

    Read the article

  • Is a Single Texture Cube Map Possible?

    - by smoth190
    I'm currently developing a test project to explore OpenGL 3 texturing abilities. I have a simple cube, made of 8 vertices and 36 indices. I want each of the cubes faces to have a different texture, so I devised this texture: I made it obvious which sections I want visible (I hope...). In Direct3D, I once made a skybox, and I used a cubemap. However, I had to split it into 6 different textures. This is annoying and hard to manage, it would be nice to have just one texture. Is this even possible? I read somewhere that I could do this by duplicating vertices, is that a good idea? Someone else said I could do it in the shader, but that also baffles me...

    Read the article

  • Continuous Movement of gun bullet

    - by Siddharth
    I was using box2d for the movement of the body. When I apply gravity (0,0) the bullet continuously move but when I change gravity to the earth the behavior was changed. I also try to apply continuous force to the bullet body but the behavior was not so good. So please provide any suggestion to continuously move bullet body in earth gravity. currentVelocity = bulletBody.getLinearVelocity(); if (currentVelocity.len() < speed|| currentVelocity.len() > speed + 0.25f) { velocityChange = Math.abs(speed - currentVelocity.len()); currentVelocity.set(currentVelocity.x* velocityChange, currentVelocity.y*velocityChange); bulletBody.applyLinearImpulse(currentVelocity,bulletBody.getWorldCenter()); } I apply above code for the continuous velocity of the body. And also I did not able to find any setGravityScale method in the library.

    Read the article

  • OpenGL ES rotate texture

    - by 0xSina
    I just got started with OpenGL ES... I have a fragment: const char * sFragment = _STRINGIFY( varying highp vec2 coordinate; precision mediump float; uniform vec4 maskC; uniform float threshold; uniform sampler2D videoframe; uniform sampler2D videosprite; uniform vec4 mask; uniform vec4 maskB; uniform int recording; vec3 normalize(vec3 color, float meanr) { return color*vec3(0.75 + meanr, 1., 1. - meanr); } void main() { float d; float dB; float dC; float meanr; float meanrB; float meanrC; float minD; vec4 pixelColor; vec4 spriteColor; pixelColor = texture2D(videoframe, coordinate); spriteColor = texture2D(videosprite, coordinate); meanr = (pixelColor.r + mask.r)/8.; meanrB = (pixelColor.r + maskB.r)/8.; meanrC = (pixelColor.r + maskC.r)/8.; d = distance(normalize(pixelColor.rgb, meanr), normalize(mask.rgb, meanr)); dB = distance(normalize(pixelColor.rgb, meanrB), normalize(maskB.rgb, meanrB)); dC = distance(normalize(pixelColor.rgb, meanrC), normalize(maskC.rgb, meanrC)); minD = min(d, dB); minD = min(minD, dC); gl_FragColor = spriteColor; if (minD > threshold) { gl_FragColor = pixelColor; } } Now, depending on wether recording is 0 or 1, I want to rotate uniform sampler2D videosprite 180 degrees (reflection in x-axis, flip vertically). How can I do that? I found the function glRotatef(), but how do i specify that I want to rotate video sprite and not videoframe? Thanks

    Read the article

  • 3D zooming technique to maintain the relative position of an object on screen

    - by stark
    Is it possible to zoom to a certain point on screen by modifying the field of view and rotating the view of the camera as to keep that point/object in the same place on screen while zooming ? Changing the camera position is not allowed. I projected the 3D pos of the object on screen and remembered it. Then on each frame I calculate the direction to it in camera space and then I construct a rotation matrix to align this direction to Z axis (in cam space). After this, I calculate the direction from the camera to the object in world space and transform this vector with the matrix I obtained earlier and then use this final vector as the camera's new direction. And it's actually "kinda working", the problem is that it is more/less off than the camera's rotation before starting to zoom depending on the area you are trying to zoom in (larger error on edges/corners). It looks acceptable, but I'm not settling for only this. Any suggestions/resources for doing this technique perfectly? If some of you want to explain the math in detail, be my guest, I can understand these things well.

    Read the article

  • Getting the number of fragments which passed the depth test

    - by Etan
    In "modern" environments, the "NV Occlusion Query" extension provides a method to get the number of fragments which passed the depth test. However, on the iPad / iPhone using OpenGL ES, the extension is not available. What is the most performant approach to implement a similar behaviour in the fragment shader? Some of my ideas: Render the object completely in white, then count all the colors together using a two-pass shader where first a vertical line is rendered and for each fragment the shader computes the sum over the whole row. Then, a single vertex is rendered whose fragment sums all the partial sums of the first pass. Doesn't seem to be very efficient. Render the object completely in white over a black background. Downsample recursively, abusing the hardware linear interpolation between textures until being at a reasonably small resolution. This leads to fragments which have a greyscale level depending on the number of white pixels where in their corresponding region. Is this even accurate enough? Use mipmaps and simply read the pixel on the 1x1 level. Again the question of accuracy and if it is even possible using non-power-of-two textures. The problem wit these approaches is, that the pipeline gets stalled which results in major performance issues. Therefore, I'm looking for a more performant way to accomplish my goal. Using the EXT_OCCLUSION_QUERY_BOOLEAN extension Apple introduced EXT_OCCLUSION_QUERY_BOOLEAN in iOS 5.0 for iPad 2. "4.1.6 Occlusion Queries Occlusion queries use query objects to track the number of fragments or samples that pass the depth test. An occlusion query can be started and finished by calling BeginQueryEXT and EndQueryEXT, respectively, with a target of ANY_SAMPLES_PASSED_EXT or ANY_SAMPLES_PASSED_CONSERVATIVE_EXT. When an occlusion query is started with the target ANY_SAMPLES_PASSED_EXT, the samples-boolean state maintained by the GL is set to FALSE. While that occlusion query is active, the samples-boolean state is set to TRUE if any fragment or sample passes the depth test. When the occlusion query finishes, the samples-boolean state of FALSE or TRUE is written to the corresponding query object as the query result value, and the query result for that object is marked as available. If the target of the query is ANY_SAMPLES_PASSED_CONSERVATIVE_EXT, an implementation may choose to use a less precise version of the test which can additionally set the samples-boolean state to TRUE in some other implementation dependent cases." The first sentence hints on a behavior which is exactly what I'm looking for: getting the number of pixels which passed the depth test in an asynchronous manner without much performance loss. However, the rest of the document describes only how to get boolean results. Is it possible to exploit this extension to get the pixel count? Does the hardware support it so that there may be hidden API to get access to the pixel count? Other extensions which could be exploitable would be debugging features like the number of times the fragment shader was invoked (PSInvocations in DirectX - not sure if something simila is available in OpenGL ES). However, this would also result in a pipeline stall.

    Read the article

  • XNA texture stretching at extreme coordinates

    - by Shaun Hamman
    I was toying around with infinitely scrolling 2D textures using the XNA framework and came across a rather strange observation. Using the basic draw code: spriteBatch.Begin(SpriteSortMode.Deferred, null, SamplerState.PointWrap, null, null); spriteBatch.Draw(texture, Vector2.Zero, sourceRect, Color.White, 0.0f, Vector2.Zero, 2.0f, SpriteEffects.None, 1.0f); spriteBatch.End(); with a small 32x32 texture and a sourceRect defined as: sourceRect = new Rectangle(0, 0, Window.ClientBounds.Width, Window.ClientBounds.Height); I was able to scroll the texture across the window infinitely by changing the X and Y coordinates of the sourceRect. Playing with different coordinate locations, I noticed that if I made either of the coordinates too large, the texture no longer drew and was instead replaced by either a flat color or alternating bands of color. Tracing the coordinates back down, I found the following at around (0, -16,777,000): As you can see, the texture in the top half of the image is stretched vertically. My question is why is this occurring? Certainly I can do things like bind the x/y position to some low multiple of 32 to give the same effect without this occurring, so fixing it isn't an issue, but I'm curious about why this happens. My initial thought was perhaps it was overflowing the coordinate value or some such thing, but looking at a data type size chart, the next closest below is an unsigned short with a range of about 32,000, and above is an unsigned int with a range of around 2,000,000,000 so that isn't likely the cause.

    Read the article

< Previous Page | 373 374 375 376 377 378 379 380 381 382 383 384  | Next Page >