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  • why no implicit conversion from pointer to reference to const pointer.

    - by user316606
    I'll illustrate my question with code: #include <iostream> void PrintInt(const unsigned char*& ptr) { int data = 0; ::memcpy(&data, ptr, sizeof(data)); // advance the pointer reference. ptr += sizeof(data); std::cout << std::hex << data << " " << std::endl; } int main(int, char**) { unsigned char buffer[] = { 0x11, 0x11, 0x11, 0x11, 0x22, 0x22, 0x22, 0x22, }; /* const */ unsigned char* ptr = buffer; PrintInt(ptr); // error C2664: ... PrintInt(ptr); // error C2664: ... return 0; } When I run this code (in VS2008) I get this: error C2664: 'PrintInt' : cannot convert parameter 1 from 'unsigned char *' to 'const unsigned char *&'. If I uncomment the "const" comment it works fine. However shouldn't pointer implicitly convert into const pointer and then reference be taken? Am I wrong in expecting this to work? Thanks!

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  • CArray doesn't call copy constructors on memory reallocations, now what?

    - by MMx
    Suppose I have a class that requires copy constructor to be called to make a correct copy of: struct CWeird { CWeird() { number = 47; target = &number; } CWeird(const CWeird &other) : number(other.number), target(&number) { } void output() { printf("%d %d\n", *target, number); } int *target, number; }; Now the trouble is that CArray doesn't call copy constructors on its elements when reallocating memory (only memcpy from the old memory to the new), e.g. this code CArray<CWeird> a; a.SetSize(1); a[0].output(); a.SetSize(2); a[0].output(); results in 47 47 -572662307 47 I don't get this. Why is it that std::vector can copy the same objects properly and CArray can't? What's the lesson here? Should I use only classes that don't require explicit copy constructors? Or is it a bad idea to use CArray for anything serious?

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  • Using memset on structures in C++

    - by garry
    Hey guys. I am working on fixing older code for my job. It is currently written in C++. They converted static allocation to dynamic but didn't edit the memsets/memcmp/memcpy. This is my first programming internship so bare with my newbe-like question. The following code is in C, but I want to have it in C++ ( I read that malloc isn't good practice in C++). I have two scenarios: First, we have f created. Then you use &f in order to fill with zero. The second is a pointer *pf. I'm not sure how to set pf to all 0's like the previous example in C++. Could you just do pf = new foo instead of malloc and then call memset(pf, 0, sizeof(foo))? struct foo { ... } f; memset( &f, 0, sizeof(f) ); //or struct foo { ... } *pf; pf = (struct foo*) malloc( sizeof(*pf) ); memset( pf, 0, sizeof(*pf) );

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  • Failing to use Array.Copy() in my WPF App

    - by Steven Wilson
    I am a C++ developer and recently started working on WPF. Well I am using Array.Copy() in my app and looks like I am not able to completely get the desired result. I had done in my C++ app as follows: static const signed char version[40] = { 'A', 'U', 'D', 'I', 'E', 'N', 'C', 'E', // name 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , // reserved, firmware size 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , // board number 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , // variant, version, serial 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 // date code, reserved }; unsigned char sendBuf[256] = {}; int memloc = 0; sendBuf[memloc++] = 0; sendBuf[memloc++] = 0; // fill in the audience header memcpy(sendBuf+memloc, version, 8); // the first 8 bytes memloc += 16; // the 8 copied, plus 8 reserved bytes I did the similar operation in my WPF (C#) app as follows: Byte[] sendBuf = new Byte[256]; char[] version = { 'A', 'U', 'D', 'I', 'E', 'N', 'C', 'E', // name '0', '0', '0', '0', '0', '0', '0', '0' , // reserved, firmware size '0', '0', '0', '0', '0', '0', '0', '0' , // board number '0', '0', '0', '0', '0', '0', '0', '0' , // variant, version, serial '0', '0', '0', '0', '0', '0', '0', '0' // date code, reserved }; // fill in the address to write to -- 0 sendBuf[memloc++] = 0; sendBuf[memloc++] = 0; // fill in the audience header Array.Copy(sendBuf + memloc, version, 8); // the first 8 bytes memloc += 16; But it throws me an error at Array.Copy(sendBuf + memloc, version, 8); as Operator '+' cannot be applied to operands of type 'byte[]' and 'int'. How can achieve this???? :) please help :)

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  • Why does setting a geometry shader cause my sprites to vanish?

    - by ChaosDev
    My application has multiple screens with different tasks. Once I set a geometry shader to the device context for my custom terrain, it works and I get the desired results. But then when I get back to the main menu, all sprites and text disappear. These sprites don't dissappear when I use pixel and vertex shaders. The sprites are being drawn through D3D11, of course, with specified view and projection matrices as well an input layout, vertex, and pixel shader. I'm trying DeviceContext->ClearState() but it does not help. Any ideas? void gGeometry::DrawIndexedWithCustomEffect(gVertexShader*vs,gPixelShader* ps,gGeometryShader* gs=nullptr) { unsigned int offset = 0; auto context = mp_D3D->mp_Context; //set topology context->IASetPrimitiveTopology(m_Topology); //set input layout context->IASetInputLayout(mp_inputLayout); //set vertex and index buffers context->IASetVertexBuffers(0,1,&mp_VertexBuffer->mp_Buffer,&m_VertexStride,&offset); context->IASetIndexBuffer(mp_IndexBuffer->mp_Buffer,mp_IndexBuffer->m_DXGIFormat,0); //send constant buffers to shaders context->VSSetConstantBuffers(0,vs->m_CBufferCount,vs->m_CRawBuffers.data()); context->PSSetConstantBuffers(0,ps->m_CBufferCount,ps->m_CRawBuffers.data()); if(gs!=nullptr) { context->GSSetConstantBuffers(0,gs->m_CBufferCount,gs->m_CRawBuffers.data()); context->GSSetShader(gs->mp_D3DGeomShader,0,0);//after this call all sprites disappear } //set shaders context->VSSetShader( vs->mp_D3DVertexShader, 0, 0 ); context->PSSetShader( ps->mp_D3DPixelShader, 0, 0 ); //draw context->DrawIndexed(m_indexCount,0,0); } //sprites void gSpriteDrawer::Draw(gTexture2D* texture,const RECT& dest,const RECT& source, const Matrix& spriteMatrix,const float& rotation,Vector2d& position,const Vector2d& origin,const Color& color) { VertexPositionColorTexture* verticesPtr; D3D11_MAPPED_SUBRESOURCE mappedResource; unsigned int TriangleVertexStride = sizeof(VertexPositionColorTexture); unsigned int offset = 0; float halfWidth = ( float )dest.right / 2.0f; float halfHeight = ( float )dest.bottom / 2.0f; float z = 0.1f; int w = texture->Width(); int h = texture->Height(); float tu = (float)source.right/(w); float tv = (float)source.bottom/(h); float hu = (float)source.left/(w); float hv = (float)source.top/(h); Vector2d t0 = Vector2d( hu+tu, hv); Vector2d t1 = Vector2d( hu+tu, hv+tv); Vector2d t2 = Vector2d( hu, hv+tv); Vector2d t3 = Vector2d( hu, hv+tv); Vector2d t4 = Vector2d( hu, hv); Vector2d t5 = Vector2d( hu+tu, hv); float ex=(dest.right/2)+(origin.x); float ey=(dest.bottom/2)+(origin.y); Vector4d v4Color = Vector4d(color.r,color.g,color.b,color.a); VertexPositionColorTexture vertices[] = { { Vector3d( dest.right-ex, -ey, z),v4Color, t0}, { Vector3d( dest.right-ex, dest.bottom-ey , z),v4Color, t1}, { Vector3d( -ex, dest.bottom-ey , z),v4Color, t2}, { Vector3d( -ex, dest.bottom-ey , z),v4Color, t3}, { Vector3d( -ex, -ey , z),v4Color, t4}, { Vector3d( dest.right-ex, -ey , z),v4Color, t5}, }; auto mp_context = mp_D3D->mp_Context; // Lock the vertex buffer so it can be written to. mp_context->Map(mp_vertexBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mappedResource); // Get a pointer to the data in the vertex buffer. verticesPtr = (VertexPositionColorTexture*)mappedResource.pData; // Copy the data into the vertex buffer. memcpy(verticesPtr, (void*)vertices, (sizeof(VertexPositionColorTexture) * 6)); // Unlock the vertex buffer. mp_context->Unmap(mp_vertexBuffer, 0); //set vertex shader mp_context->IASetVertexBuffers( 0, 1, &mp_vertexBuffer, &TriangleVertexStride, &offset); //set texture mp_context->PSSetShaderResources( 0, 1, &texture->mp_SRV); //set matrix to shader mp_context->UpdateSubresource(mp_matrixBuffer, 0, 0, &spriteMatrix, 0, 0 ); mp_context->VSSetConstantBuffers( 0, 1, &mp_matrixBuffer); //draw sprite mp_context->Draw( 6, 0 ); }

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  • i am using winsock2.h in c language the following errors are unuderstandable help required?

    - by moon
    i am going to paste here my code an errors :::: #include "stdio.h" #include "winsock2.h" #define SIO_RCVALL _WSAIOW(IOC_VENDOR,1) //this removes the need of mstcpip.h void StartSniffing (SOCKET Sock); //This will sniff here and there void ProcessPacket (unsigned char* , int); //This will decide how to digest void PrintIpHeader (unsigned char* , int); void PrintUdpPacket (unsigned char* , int); void ConvertToHex (unsigned char* , unsigned int); void PrintData (unsigned char* , int); //IP Header Structure typedef struct ip_hdr { unsigned char ip_header_len:4; // 4-bit header length (in 32-bit words) normally=5 (Means 20 Bytes may be 24 also) unsigned char ip_version :4; // 4-bit IPv4 version unsigned char ip_tos; // IP type of service unsigned short ip_total_length; // Total length unsigned short ip_id; // Unique identifier unsigned char ip_frag_offset :5; // Fragment offset field unsigned char ip_more_fragment :1; unsigned char ip_dont_fragment :1; unsigned char ip_reserved_zero :1; unsigned char ip_frag_offset1; //fragment offset unsigned char ip_ttl; // Time to live unsigned char ip_protocol; // Protocol(TCP,UDP etc) unsigned short ip_checksum; // IP checksum unsigned int ip_srcaddr; // Source address unsigned int ip_destaddr; // Source address } IPV4_HDR; //UDP Header Structure typedef struct udp_hdr { unsigned short source_port; // Source port no. unsigned short dest_port; // Dest. port no. unsigned short udp_length; // Udp packet length unsigned short udp_checksum; // Udp checksum (optional) } UDP_HDR; //ICMP Header Structure typedef struct icmp_hdr { BYTE type; // ICMP Error type BYTE code; // Type sub code USHORT checksum; USHORT id; USHORT seq; } ICMP_HDR; FILE *logfile; int tcp=0,udp=0,icmp=0,others=0,igmp=0,total=0,i,j; struct sockaddr_in source,dest; char hex[2]; //Its free! IPV4_HDR *iphdr; UDP_HDR *udpheader; int main() { SOCKET sniffer; struct in_addr addr; int in; char hostname[100]; struct hostent *local; WSADATA wsa; //logfile=fopen("log.txt","w"); //if(logfile==NULL) printf("Unable to create file."); //Initialise Winsock printf("\nInitialising Winsock..."); if (WSAStartup(MAKEWORD(2,2), &wsa) != 0) { printf("WSAStartup() failed.\n"); return 1; } printf("Initialised"); //Create a RAW Socket printf("\nCreating RAW Socket..."); sniffer = socket(AF_INET, SOCK_RAW, IPPROTO_IP); if (sniffer == INVALID_SOCKET) { printf("Failed to create raw socket.\n"); return 1; } printf("Created."); //Retrive the local hostname if (gethostname(hostname, sizeof(hostname)) == SOCKET_ERROR) { printf("Error : %d",WSAGetLastError()); return 1; } printf("\nHost name : %s \n",hostname); //Retrive the available IPs of the local host local = gethostbyname(hostname); printf("\nAvailable Network Interfaces : \n"); if (local == NULL) { printf("Error : %d.\n",WSAGetLastError()); return 1; } for (i = 0; local->h_addr_list[i] != 0; ++i) { memcpy(&addr, local->h_addr_list[i], sizeof(struct in_addr)); printf("Interface Number : %d Address : %s\n",i,inet_ntoa(addr)); } printf("Enter the interface number you would like to sniff : "); scanf("%d",&in); memset(&dest, 0, sizeof(dest)); memcpy(&dest.sin_addr.s_addr,local->h_addr_list[in],sizeof(dest.sin_addr.s_addr)); dest.sin_family = AF_INET; dest.sin_port = 0; printf("\nBinding socket to local system and port 0 ..."); if (bind(sniffer,(struct sockaddr *)&dest,sizeof(dest)) == SOCKET_ERROR) { printf("bind(%s) failed.\n", inet_ntoa(addr)); return 1; } printf("Binding successful"); //Enable this socket with the power to sniff : SIO_RCVALL is the key Receive ALL ;) j=1; printf("\nSetting socket to sniff..."); if (WSAIoctl(sniffer, SIO_RCVALL,&j, sizeof(j), 0, 0,(LPDWORD)&in,0, 0) == SOCKET_ERROR) { printf("WSAIoctl() failed.\n"); return 1; } printf("Socket set."); //Begin printf("\nStarted Sniffing\n"); printf("Packet Capture Statistics...\n"); StartSniffing(sniffer); //Happy Sniffing //End closesocket(sniffer); WSACleanup(); return 0; } void StartSniffing(SOCKET sniffer) { unsigned char *Buffer = ( unsigned char *)malloc(65536); //Its Big! int mangobyte; if (Buffer == NULL) { printf("malloc() failed.\n"); return; } do { mangobyte = recvfrom(sniffer,(char *)Buffer,65536,0,0,0); //Eat as much as u can if(mangobyte > 0) ProcessPacket(Buffer, mangobyte); else printf( "recvfrom() failed.\n"); } while (mangobyte > 0); free(Buffer); } void ProcessPacket(unsigned char* Buffer, int Size) { iphdr = (IPV4_HDR *)Buffer; ++total; switch (iphdr->ip_protocol) //Check the Protocol and do accordingly... { case 1: //ICMP Protocol ++icmp; //PrintIcmpPacket(Buffer,Size); break; case 2: //IGMP Protocol ++igmp; break; case 6: //TCP Protocol ++tcp; //PrintTcpPacket(Buffer,Size); break; case 17: //UDP Protocol ++udp; PrintUdpPacket(Buffer,Size); break; default: //Some Other Protocol like ARP etc. ++others; break; } printf("TCP : %d UDP : %d ICMP : %d IGMP : %d Others : %d Total : %d\r",tcp,udp,icmp,igmp,others,total); } void PrintIpHeader (unsigned char* Buffer, int Size) { unsigned short iphdrlen; iphdr = (IPV4_HDR *)Buffer; iphdrlen = iphdr->ip_header_len*4; memset(&source, 0, sizeof(source)); source.sin_addr.s_addr = iphdr->ip_srcaddr; memset(&dest, 0, sizeof(dest)); dest.sin_addr.s_addr = iphdr->ip_destaddr; fprintf(logfile,"\n"); fprintf(logfile,"IP Header\n"); fprintf(logfile," |-IP Version : %d\n",(unsigned int)iphdr->ip_version); fprintf(logfile," |-IP Header Length : %d DWORDS or %d Bytes\n",(unsigned int)iphdr->ip_header_len); fprintf(logfile," |-Type Of Service : %d\n",(unsigned int)iphdr->ip_tos); fprintf(logfile," |-IP Total Length : %d Bytes(Size of Packet)\n",ntohs(iphdr->ip_total_length)); fprintf(logfile," |-Identification : %d\n",ntohs(iphdr->ip_id)); fprintf(logfile," |-Reserved ZERO Field : %d\n",(unsigned int)iphdr->ip_reserved_zero); fprintf(logfile," |-Dont Fragment Field : %d\n",(unsigned int)iphdr->ip_dont_fragment); fprintf(logfile," |-More Fragment Field : %d\n",(unsigned int)iphdr->ip_more_fragment); fprintf(logfile," |-TTL : %d\n",(unsigned int)iphdr->ip_ttl); fprintf(logfile," |-Protocol : %d\n",(unsigned int)iphdr->ip_protocol); fprintf(logfile," |-Checksum : %d\n",ntohs(iphdr->ip_checksum)); fprintf(logfile," |-Source IP : %s\n",inet_ntoa(source.sin_addr)); fprintf(logfile," |-Destination IP : %s\n",inet_ntoa(dest.sin_addr)); } void PrintUdpPacket(unsigned char *Buffer,int Size) { unsigned short iphdrlen; iphdr = (IPV4_HDR *)Buffer; iphdrlen = iphdr->ip_header_len*4; udpheader = (UDP_HDR *)(Buffer + iphdrlen); fprintf(logfile,"\n\n***********************UDP Packet*************************\n"); PrintIpHeader(Buffer,Size); fprintf(logfile,"\nUDP Header\n"); fprintf(logfile," |-Source Port : %d\n",ntohs(udpheader->source_port)); fprintf(logfile," |-Destination Port : %d\n",ntohs(udpheader->dest_port)); fprintf(logfile," |-UDP Length : %d\n",ntohs(udpheader->udp_length)); fprintf(logfile," |-UDP Checksum : %d\n",ntohs(udpheader->udp_checksum)); fprintf(logfile,"\n"); fprintf(logfile,"IP Header\n"); PrintData(Buffer,iphdrlen); fprintf(logfile,"UDP Header\n"); PrintData(Buffer+iphdrlen,sizeof(UDP_HDR)); fprintf(logfile,"Data Payload\n"); PrintData(Buffer+iphdrlen+sizeof(UDP_HDR) ,(Size - sizeof(UDP_HDR) - iphdr->ip_header_len*4)); fprintf(logfile,"\n###########################################################"); } void PrintData (unsigned char* data , int Size) { for(i=0 ; i < Size ; i++) { if( i!=0 && i%16==0) //if one line of hex printing is complete... { fprintf(logfile," "); for(j=i-16 ; j<i ; j++) { if(data[j]>=32 && data[j]<=128) fprintf(logfile,"%c",(unsigned char)data[j]); //if its a number or alphabet else fprintf(logfile,"."); //otherwise print a dot } fprintf(logfile,"\n"); } if(i%16==0) fprintf(logfile," "); fprintf(logfile," %02X",(unsigned int)data[i]); if( i==Size-1) //print the last spaces { for(j=0;j<15-i%16;j++) fprintf(logfile," "); //extra spaces fprintf(logfile," "); for(j=i-i%16 ; j<=i ; j++) { if(data[j]>=32 && data[j]<=128) fprintf(logfile,"%c",(unsigned char)data[j]); else fprintf(logfile,"."); } fprintf(logfile,"\n"); } } } following are the errors Error 1 error LNK2019: unresolved external symbol __imp__WSACleanup@0 referenced in function _main sniffer.obj sniffer test Error 2 error LNK2019: unresolved external symbol __imp__closesocket@4 referenced in function _main sniffer.obj sniffer test Error 3 error LNK2019: unresolved external symbol __imp__WSAIoctl@36 referenced in function _main sniffer.obj sniffer test Error 4 error LNK2019: unresolved external symbol __imp__bind@12 referenced in function _main sniffer.obj sniffer test Error 5 error LNK2019: unresolved external symbol __imp__inet_ntoa@4 referenced in function _main sniffer.obj sniffer test Error 6 error LNK2019: unresolved external symbol __imp__gethostbyname@4 referenced in function _main sniffer.obj sniffer test Error 7 error LNK2019: unresolved external symbol __imp__WSAGetLastError@0 referenced in function _main sniffer.obj sniffer test Error 8 error LNK2019: unresolved external symbol __imp__gethostname@8 referenced in function _main sniffer.obj sniffer test Error 9 error LNK2019: unresolved external symbol __imp__socket@12 referenced in function _main sniffer.obj sniffer test Error 10 error LNK2019: unresolved external symbol __imp__WSAStartup@8 referenced in function _main sniffer.obj sniffer test Error 11 error LNK2019: unresolved external symbol __imp__recvfrom@24 referenced in function "void __cdecl StartSniffing(unsigned int)" (?StartSniffing@@YAXI@Z) sniffer.obj sniffer test Error 12 error LNK2019: unresolved external symbol __imp__ntohs@4 referenced in function "void __cdecl PrintIpHeader(unsigned char *,int)" (?PrintIpHeader@@YAXPAEH@Z) sniffer.obj sniffer test Error 13 fatal error LNK1120: 12 unresolved externals E:\CWM\sniffer test\Debug\sniffer test.exe sniffer test

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  • Issue with dynamic array Queue data structure with void pointer

    - by Nazgulled
    Hi, Maybe there's no way to solve this the way I'd like it but I don't know everything so I better ask... I've implemented a simple Queue with a dynamic array so the user can initialize with whatever number of items it wants. I'm also trying to use a void pointer as to allow any data type, but that's the problem. Here's my code: typedef void * QueueValue; typedef struct sQueueItem { QueueValue value; } QueueItem; typedef struct sQueue { QueueItem *items; int first; int last; int size; int count; } Queue; void queueInitialize(Queue **queue, size_t size) { *queue = xmalloc(sizeof(Queue)); QueueItem *items = xmalloc(sizeof(QueueItem) * size); (*queue)->items = items; (*queue)->first = 0; (*queue)->last = 0; (*queue)->size = size; (*queue)->count = 0; } Bool queuePush(Queue * const queue, QueueValue value, size_t val_sz) { if(isNull(queue) || isFull(queue)) return FALSE; queue->items[queue->last].value = xmalloc(val_sz); memcpy(queue->items[queue->last].value, value, val_sz); queue->last = (queue->last+1) % queue->size; queue->count += 1; return TRUE; } Bool queuePop(Queue * const queue, QueueValue *value) { if(isEmpty(queue)) return FALSE; *value = queue->items[queue->first].value; free(queue->items[queue->first].value); queue->first = (queue->first+1) % queue->size; queue->count -= 1; return TRUE; } The problem lies on the queuePop function. When I call it, I lose the value because I free it right away. I can't seem to solve this dilemma. I want my library to be generic and modular. The user should not care about allocating and freeing memory, that's the library's job. How can the user still get the value from queuePop and let the library handle all memory allocs/frees?

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  • Cocoa NSOutputStream send to a connection

    - by Chuck
    Hi, I am new to Cocoa, but managed to get a connection (to a FTP) up and running, and I've set up an eventhandler for the NSInputStream iStream to alert every response (which also works). What I manage to get is simply the hello message and a connection timeout 60 sec, closing control connection. After searching stackoverflow and finding a lot of NSOutputStream write problems (e.g. http://stackoverflow.com/questions/703729/how-to-use-nsoutputstreams-write-message) and a lot of confusion in my google hits, I figured I'd try to ask my own question: I've tried reading the developer.apple.com doc on OutputStream, but it seems almost impossible for me to send some data (in this case just a string) to the "connection" via the NSOutputStream oStream. - (IBAction) send_something: sender { const char *send_command_char = [@"USER foo" UTF8String]; send_command_buffer = [NSMutableData dataWithBytes:send_command_char length:strlen(send_command_char) + 1]; uint8_t *readBytes = (uint8_t *)[send_command_buffer mutableBytes]; NSInteger byteIndex = 0; readBytes += byteIndex; int data_len = [send_command_buffer length]; unsigned int len = ((data_len - byteIndex >= 1024) ? 1024 : (data_len-byteIndex)); uint8_t buf[len]; (void)memcpy(buf, readBytes, len); len = [oStream write:(const uint8_t *)buf maxLength:len]; byteIndex += len; } the above seems not to result in any useable events. typing it under NSStreamEventHasSpaceAvailable sometimes give a response if I spam the ftp by keep creating new connection instances and keep sending some command whenever oStream has free space. In other words, nothing "right" and so I'm still unclear how to properly send a command to the connection. Should I open - write - close every time i want to write to oStream (and thus to the ftp) and can I then expect a reply (hasBytesAvailable event on iStream)? For some reason I find it very difficult to find any clear tutorials on this matter. Seems like there are more than a few in the same position as me: unclear how to use oStream write? Any little bit that can help clear this up is greatly appreciated! If needed I can write the rest of the code. Chuck

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  • Efficient list compacting

    - by Patrik
    Suppose you have a list of unsigned ints. Suppose some elements are equal to 0 and you want to push them back. Currently I use this code (list is a pointer to a list of unsigned ints of size n for (i = 0; i < n; ++i) { if (list[i]) continue; int j; for (j = i + 1; j < n && !list[j]; ++j); int z; for (z = j + 1; z < n && list[z]; ++z); if (j == n) break; memmove(&(list[i]), &(list[j]), sizeof(unsigned int) * (z - j))); int s = z - j + i; for(j = s; j < z; ++j) list[j] = 0; i = s - 1; } Can you think of a more efficient way to perform this task? The snippet is purely theoretical, in the production code, each element of list is a 64 bytes struct EDIT: I'll post my solution. Many thanks to Jonathan Leffler. void RemoveDeadParticles(int * list, int * n) { int i, j = *n - 1; for (; j >= 0 && list[j] == 0; --j); for (i = 0; i < j; ++i) { if (list[i]) continue; memcpy(&(list[i]), &(list[j]), sizeof(int)); list[j] = 0; for (; j >= 0 && list[j] == 0; --j); if (i == j) break; } *n = i + 1; }

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  • How can I create a Base64-Encoded string from an GDI+ Image in C++?

    - by Schnapple
    I asked a question recently, How can I create an Image in GDI+ from a Base64-Encoded string in C++?, which got a response that led me to the answer. Now I need to do the opposite - I have an Image in GDI+ whose image data I need to turn into a Base64-Encoded string. Due to its nature, it's not straightforward. The crux of the issue is that an Image in GDI+ can save out its data to either a file or an IStream*. I don't want to save to a file, so I need to use the resulting stream. Problem is, this is where my knowledge breaks down. This first part is what I figured out in the other question // Initialize GDI+. GdiplusStartupInput gdiplusStartupInput; ULONG_PTR gdiplusToken; GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL); // I have this decode function from elsewhere std::string decodedImage = base64_decode(Base64EncodedImage); // Allocate the space for the stream DWORD imageSize = decodedImage.length(); HGLOBAL hMem = ::GlobalAlloc(GMEM_MOVEABLE, imageSize); LPVOID pImage = ::GlobalLock(hMem); memcpy(pImage, decodedImage.c_str(), imageSize); // Create the stream IStream* pStream = NULL; ::CreateStreamOnHGlobal(hMem, FALSE, &pStream); // Create the image from the stream Image image(pStream); // Cleanup pStream->Release(); GlobalUnlock(hMem); GlobalFree(hMem); (Base64 code) And now I'm going to perform an operation on the resulting image, in this case rotating it, and now I want the Base64-equivalent string when I'm done. // Perform operation (rotate) image.RotateFlip(Gdiplus::Rotate180FlipNone); IStream* oStream = NULL; CLSID tiffClsid; GetEncoderClsid(L"image/tiff", &tiffClsid); // Function defined elsewhere image.Save(oStream, &tiffClsid); // And here's where I'm stumped. (GetEncoderClsid) So what I wind up with at the end is an IStream* object. But here's where both my knowledge and Google break down for me. IStream shouldn't be an object itself, it's an interface for other types of streams. I'd go down the road from getting string-Image in reverse, but I don't know how to determine the size of the stream, which appears to be key to that route. How can I go from an IStream* to a string (which I will then Base64-Encode)? Or is there a much better way to go from a GDI+ Image to a string?

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  • iphone problem receiving UDP packets

    - by SooDesuNe
    I'm using sendto() and recvfrom() to send some simple packets via UDP over WiFI. I've tried using two phones, and a simulator, the results I'm getting are: Packets sent from phones - recieved by simulator Packets sent from simulator - simulator recvfrom remains blocking. Packets sent from phones - other phone recvfrom remains blocking. I'm not sure how to start debugging this one, since the simulator/mac is able to receive the the packets, but the phones don't appear to be getting the message. A slight aside, do I need to keep my packets below the MTU for my network? Or is fragmentation handled by the OS or some other lower level software? UPDATE: I forgot to include the packet size and structure. I'm transmitting: typedef struct PacketForTransmission { int32_t packetTypeIdentifier; char data[64]; // size to fit my biggest struct } PacketForTransmission; of which the char data[64] is: typedef struct PacketHeader{ uint32_t identifier; uint32_t datatype; } PacketHeader; typedef struct BasePacket{ PacketHeader header; int32_t cardValue; char sendingDeviceID[41]; //dont forget to save room for the NULL terminator! } BasePacket; typedef struct PositionPacket{ BasePacket basePacket; int32_t x; int32_t y; } PositionPacket; sending packet is like: PositionPacket packet; bzero(&packet, sizeof(packet)); //fill packet with it's associated data PacketForTransmission transmissionPacket; transmissionPacket.packetTypeIdentifier = kPositionPacketType; memcpy(&transmissionPacket.data, (void*)&packet, sizeof(packet)); //put the PositionPacket into data[64] size_t sendResult = sendto(_socket, &transmissionPacket, sizeof(transmissionPacket), 0, [address bytes], [address length]); NSLog(@"packet sent of size: %i", sendResult); and recieving packets is like: while(1){ char dataBuffer[8192]; struct sockaddr addr; socklen_t socklen = sizeof(addr); ssize_t len = recvfrom(_socket, dataBuffer, sizeof(dataBuffer), 0, &addr, &socklen); //continues blocking here NSLog(@"packet recieved of length: %i", len); //do some more stuff }

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  • Syntax error while copying an multidimensional array to another in C

    - by mantuko
    We are programming a ST269 microcontroller which has two IR distance sensors. To calibrate these sensors we made one table for each sensor with the distance we measured and the corresponding value we get from the ADC. Now we want to use one function to approximate the values in between. So we defined two two-dimensional arrays (one for each sensor) as global variables. In our function we then want to copy the one array we want to work with to a working array and approximate our values. So here's the code: ... unsigned int ir_werte_re[][] = { {8,553}, ... {83,133} }; unsigned int ir_werte_li[][] = { {8,566}, ... {83,147} }; ... unsigned int geradenaproximation(unsigned int messwert, unsigned int seite) { unsigned int working_array[16][16]; unsigned int i = 0; if (seite == 0) { for (i = 0; i < sizeof(working_array); i++) { working_array[i][0] = ir_werte_li[i][0]; i++; } } else { for (i = 0; i < sizeof(working_array); i++) { working_array[i][0] = ir_werte_re[i][0]; i++; } } i = 0; unsigned int y1 = 0; unsigned int x1 = 0; ... } This code is in a file called sensor.c. We didn't write anything about our global arrays in the sensor.h should we? The sensor.h of course is included in our main.c and there the function is called. We also tried to copy the arrays via memcpy(working_array, ir_werte_li, sizeof(working_array)); And in every way we do this we get a syntax error near unsigned in the line where we're declaring unsigned int y1 = 0; and I'm pretty sure that there is no syntax error in this line : ) The last time I spend coding in C is a few years away so I'm not sure if the way we try to do this is good. Perhaps we can solve this by using a pointer instead of really copying the array or something. So please help me out I'll appreciate your bits on this.

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  • probelm with recv() on a tcp connection

    - by michael
    Hi, I am simulating TCP communication on windows in C I have sender and a receiver communicating. sender sends packets of specific size to receiver. receiver gets them and send an ACK for each packet it received back to the sender. If the sender didn't get a specific packet (they are numbered in a header inside the packet) it sends the packet again to the receiver. Here is the getPacket function on the receiver side: //get the next packet from the socket. set the packetSize to -1 //if it's the first packet. //return: total bytes read // return: 0 if socket has shutdown on sender side, -1 error, else number of bytes received int getPakcet(char *chunkBuff,int packetSize,SOCKET AcceptSocket){ int totalChunkLen = 0; int bytesRecv=-1; bool firstTime=false; if (packetSize==-1) { packetSize=MAX_PACKET_LENGTH; firstTime=true; } int needToGet=packetSize; do { char* recvBuff; recvBuff = (char*)calloc(needToGet,sizeof(char)); if(recvBuff == NULL){ fprintf(stderr,"Memory allocation problem\n"); return -1; } bytesRecv = recv(AcceptSocket, recvBuff, needToGet, 0); if (bytesRecv == SOCKET_ERROR){ fprintf(stderr,"recv() error %ld.\n", WSAGetLastError()); totalChunkLen=-1; return -1; } if (bytesRecv == 0){ fprintf(stderr,"recv(): socket has shutdown on sender side"); return 0; } else if(bytesRecv > 0) { memcpy(chunkBuff + totalChunkLen,recvBuff,bytesRecv); totalChunkLen+=bytesRecv; } needToGet-=bytesRecv; } while ((totalChunkLen < packetSize) && (!firstTime)); return totalChunkLen; } i use firstTime because for the first time the receiver doesn't know the normal package size that the sender is going to send to it, so i use a MAX_PACKET_LENGTH to get a package and then set the normal package size to the num of bytes i have received my problem is the last package. it's size is less than the package size so lets say last package size is 2 and the normal package size is 4. so recv() gets two bytes, continues to the while condition, then totalChunkLen < packetSize because 2<4 so it iterates the loop again and the gets stuck in recv() because it's blocking because the sender has nothing to send. on the sender side i can't close the connection because i didn't ACK back, so it's kind of a deadlock. receiver is stuck because it's waiting for more packages but sender has nothing to send. i don't want to use a timeout for recv() or to insert a special character to the package header to mark that it is the last one what can i do ? thanks

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  • matrix multiplication with MPI [on hold]

    - by user3695701
    I'm working on an assignment on matrix multiplication with MPI. A*B=C. the requirement is that B should be vertically partitioned. Here's what I intend to do: broadcast matrix A to all processes and scatter B into several slices with each slice containing n/p columns. The following code only works when the number of process(p) is 1. when p1(say 2), I got [cluster2:21080] *** Process received signal *** [cluster2:21080] Signal: Segmentation fault (11) [cluster2:21080] Signal code: Address not mapped (1) [cluster2:21080] Failing at address: (nil) [cluster2:21080] [ 0] /lib/libpthread.so.0(+0xf8f0) [0x7f49f38108f0] [cluster2:21080] [ 1] /lib/libc.so.6(memcpy+0xe1) [0x7f49f35024c1] [cluster2:21080] [ 2] /usr/lib/libmpi.so.0(ompi_convertor_unpack+0x121)[0x7f49f47c88e1] [cluster2:21080] [ 3] /usr/lib/openmpi/lib/openmpi/mca_pml_ob1.so(+0x8a26) [0x7f49f0dcea26] [cluster2:21080] [ 4] /usr/lib/openmpi/lib/openmpi/mca_btl_tcp.so(+0x662c) [0x7f49efce462c] [cluster2:21080] [ 5] /usr/lib/libopen-pal.so.0(+0x1ede8) [0x7f49f42e0de8] [cluster2:21080] [ 6] /usr/lib/libopen-pal.so.0(opal_progress+0x99) [0x7f49f42d5369] [cluster2:21080] [ 7] /usr/lib/openmpi/lib/openmpi/mca_pml_ob1.so(+0x5585) [0x7f49f0dcb585] [cluster2:21080] [ 8] /usr/lib/openmpi/lib/openmpi/mca_coll_tuned.so(+0xcc01) [0x7f49eeeb1c01] [cluster2:21080] [ 9] /usr/lib/openmpi/lib/openmpi/mca_coll_tuned.so(+0x266c) [0x7f49eeea766c] [cluster2:21080] [10] /usr/lib/openmpi/lib/openmpi/mca_coll_sync.so(+0x1388) [0x7f49ef0c0388] [cluster2:21080] [11] /usr/lib/libmpi.so.0(MPI_Bcast+0x10e) [0x7f49f47d025e] [cluster2:21080] [12] ./out(main+0x259) [0x401571] [cluster2:21080] [13] /lib/libc.so.6(__libc_start_main+0xfd) [0x7f49f3498c8d] [cluster2:21080] [14] ./out() [0x400f29] [cluster2:21080] *** End of error message *** Can someone help me? Thanks. //matrices A and B //double* A =(double *)malloc(n*n*sizeof(double)); //double* B =(double *)malloc(n*n*sizeof(double)); //code initializing A,B... //n is the size of the matrix //p is the number of processes //myrank is the rank of calling process MPI_Init (&argc, &argv); MPI_Comm_rank(MPI_COMM_WORLD, &myrank); MPI_Comm_size(MPI_COMM_WORLD, &p); //broadcast A to all processes MPI_Bcast (A, n*n, MPI_DOUBLE, 0, MPI_COMM_WORLD); MPI_Datatype tmp_type, col_type; // extract a slice from B MPI_Type_vector(n, num_of_col_per_slice, n, MPI_DOUBLE, &tmp_type); // position of the first (0) and each next (stride * sizeof(double) ) slice MPI_Type_create_resized(tmp_type, 0, n * sizeof(double), &col_type); MPI_Type_commit(&col_type); //scatter a slice of B to each process MPI_Scatter(B, 1, col_type, B+myrank*n/p, n * n/p, MPI_DOUBLE, 0, MPI_COMM_WORLD); //use blas function to calculate A*sliceOfB and store the resulting slice to C cblas_dgemm(CblasRowMajor, CblasNoTrans, CblasNoTrans, n, n/p, n, 1.0, A, n, B+myrank*n/p, n, 0.0, C+myrank*n/p, n); //gather all those resulting slices into C MPI_Gather (C+myrank*n/p, n*n/p, MPI_DOUBLE, C, n*n/p, MPI_DOUBLE, 0, MPI_COMM_WORLD);

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  • Segfault when iterating over a map<string, string> and drawing its contents using SDL_TTF

    - by Michael Stahre
    I'm not entirely sure this question belongs on gamedev.stackexchange, but I'm technically working on a game and working with SDL, so it might not be entirely offtopic. I've written a class called DebugText. The point of the class is to have a nice way of printing values of variables to the game screen. The idea is to call SetDebugText() with the variables in question every time they change or, as is currently the case, every time the game's Update() is called. The issue is that when iterating over the map that contains my variables and their latest updated values, I get segfaults. See the comments in DrawDebugText() below, it specifies where the error happens. I've tried splitting the calls to it-first and it-second into separate lines and found that the problem doesn't always happen when calling it-first. It alters between it-first and it-second. I can't find a pattern. It doesn't fail on every call to DrawDebugText() either. It might fail on the third time DrawDebugText() is called, or it might fail on the fourth. Class header: #ifndef CLIENT_DEBUGTEXT_H #define CLIENT_DEBUGTEXT_H #include <Map> #include <Math.h> #include <sstream> #include <SDL.h> #include <SDL_ttf.h> #include "vector2.h" using std::string; using std::stringstream; using std::map; using std::pair; using game::Vector2; namespace game { class DebugText { private: TTF_Font* debug_text_font; map<string, string>* debug_text_list; public: void SetDebugText(string var, bool value); void SetDebugText(string var, float value); void SetDebugText(string var, int value); void SetDebugText(string var, Vector2 value); void SetDebugText(string var, string value); int DrawDebugText(SDL_Surface*, SDL_Rect*); void InitDebugText(); void Clear(); }; } #endif Class source file: #include "debugtext.h" namespace game { // Copypasta function for handling the toString conversion template <class T> inline string to_string (const T& t) { stringstream ss (stringstream::in | stringstream::out); ss << t; return ss.str(); } // Initializes SDL_TTF and sets its font void DebugText::InitDebugText() { if(TTF_WasInit()) TTF_Quit(); TTF_Init(); debug_text_font = TTF_OpenFont("LiberationSans-Regular.ttf", 16); TTF_SetFontStyle(debug_text_font, TTF_STYLE_NORMAL); } // Iterates over the current debug_text_list and draws every element on the screen. // After drawing with SDL you need to get a rect specifying the area on the screen that was changed and tell SDL that this part of the screen needs to be updated. this is done in the game's Draw() function // This function sets rects_to_update to the new list of rects provided by all of the surfaces and returns the number of rects in the list. These two parameters are used in Draw() when calling on SDL_UpdateRects(), which takes an SDL_Rect* and a list length int DebugText::DrawDebugText(SDL_Surface* screen, SDL_Rect* rects_to_update) { if(debug_text_list == NULL) return 0; if(!TTF_WasInit()) InitDebugText(); rects_to_update = NULL; // Specifying the font color SDL_Color font_color = {0xff, 0x00, 0x00, 0x00}; // r, g, b, unused int row_count = 0; string line; // The iterator variable map<string, string>::iterator it; // Gets the iterator and iterates over it for(it = debug_text_list->begin(); it != debug_text_list->end(); it++) { // Takes the first value (the name of the variable) and the second value (the value of the parameter in string form) //---------THIS LINE GIVES ME SEGFAULTS----- line = it->first + ": " + it->second; //------------------------------------------ // Creates a surface with the text on it that in turn can be rendered to the screen itself later SDL_Surface* debug_surface = TTF_RenderText_Solid(debug_text_font, line.c_str(), font_color); if(debug_surface == NULL) { // A standard check for errors fprintf(stderr, "Error: %s", TTF_GetError()); return NULL; } else { // If SDL_TTF did its job right, then we now set a destination rect row_count++; SDL_Rect dstrect = {5, 5, 0, 0}; // x, y, w, h dstrect.x = 20; dstrect.y = 20*row_count; // Draws the surface with the text on it to the screen int res = SDL_BlitSurface(debug_surface,NULL,screen,&dstrect); if(res != 0) { //Just an error check fprintf(stderr, "Error: %s", SDL_GetError()); return NULL; } // Creates a new rect to specify the area that needs to be updated with SDL_Rect* new_rect_to_update = (SDL_Rect*) malloc(sizeof(SDL_Rect)); new_rect_to_update->h = debug_surface->h; new_rect_to_update->w = debug_surface->w; new_rect_to_update->x = dstrect.x; new_rect_to_update->y = dstrect.y; // Just freeing the surface since it isn't necessary anymore SDL_FreeSurface(debug_surface); // Creates a new list of rects with room for the new rect SDL_Rect* newtemp = (SDL_Rect*) malloc(row_count*sizeof(SDL_Rect)); // Copies the data from the old list of rects to the new one memcpy(newtemp, rects_to_update, (row_count-1)*sizeof(SDL_Rect)); // Adds the new rect to the new list newtemp[row_count-1] = *new_rect_to_update; // Frees the memory used by the old list free(rects_to_update); // And finally redirects the pointer to the old list to the new list rects_to_update = newtemp; newtemp = NULL; } } // When the entire map has been iterated over, return the number of lines that were drawn, ie. the number of rects in the returned rect list return row_count; } // The SetDebugText used by all the SetDebugText overloads // Takes two strings, inserts them into the map as a pair void DebugText::SetDebugText(string var, string value) { if (debug_text_list == NULL) { debug_text_list = new map<string, string>(); } debug_text_list->erase(var); debug_text_list->insert(pair<string, string>(var, value)); } // Writes the bool to a string and calls SetDebugText(string, string) void DebugText::SetDebugText(string var, bool value) { string result; if (value) result = "True"; else result = "False"; SetDebugText(var, result); } // Does the same thing, but uses to_string() to convert the float void DebugText::SetDebugText(string var, float value) { SetDebugText(var, to_string(value)); } // Same as above, but int void DebugText::SetDebugText(string var, int value) { SetDebugText(var, to_string(value)); } // Vector2 is a struct of my own making. It contains the two float vars x and y void DebugText::SetDebugText(string var, Vector2 value) { SetDebugText(var + ".x", to_string(value.x)); SetDebugText(var + ".y", to_string(value.y)); } // Empties the list. I don't actually use this in my code. Shame on me for writing something I don't use. void DebugText::Clear() { if(debug_text_list != NULL) debug_text_list->clear(); } }

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  • UV Atlas Generation and Seam Removal

    - by P. Avery
    I'm generating light maps for scene mesh objects using DirectX's UV Atlas Tool( D3DXUVAtlasCreate() ). I've succeeded in generating an atlas, however, when I try to render the mesh object using the atlas the seams are visible on the mesh. Below are images of a lightmap generated for a cube. Here is the code I use to generate a uv atlas for a cube: struct sVertexPosNormTex { D3DXVECTOR3 vPos, vNorm; D3DXVECTOR2 vUV; sVertexPosNormTex(){} sVertexPosNormTex( D3DXVECTOR3 v, D3DXVECTOR3 n, D3DXVECTOR2 uv ) { vPos = v; vNorm = n; vUV = uv; } ~sVertexPosNormTex() { } }; // create a light map texture to fill programatically hr = D3DXCreateTexture( pd3dDevice, 128, 128, 1, 0, D3DFMT_A8R8G8B8, D3DPOOL_MANAGED, &pLightmap ); if( FAILED( hr ) ) { DebugStringDX( "Main", "Failed to D3DXCreateTexture( lightmap )", __LINE__, hr ); return hr; } // get the zero level surface from the texture IDirect3DSurface9 *pS = NULL; pLightmap->GetSurfaceLevel( 0, &pS ); // clear surface pd3dDevice->ColorFill( pS, NULL, D3DCOLOR_XRGB( 0, 0, 0 ) ); // load a sample mesh DWORD dwcMaterials = 0; LPD3DXBUFFER pMaterialBuffer = NULL; V_RETURN( D3DXLoadMeshFromX( L"cube3.x", D3DXMESH_MANAGED, pd3dDevice, &pAdjacency, &pMaterialBuffer, NULL, &dwcMaterials, &g_pMesh ) ); // generate adjacency DWORD *pdwAdjacency = new DWORD[ 3 * g_pMesh->GetNumFaces() ]; g_pMesh->GenerateAdjacency( 1e-6f, pdwAdjacency ); // create light map coordinates LPD3DXMESH pMesh = NULL; LPD3DXBUFFER pFacePartitioning = NULL, pVertexRemapArray = NULL; FLOAT resultStretch = 0; UINT numCharts = 0; hr = D3DXUVAtlasCreate( g_pMesh, 0, 0, 128, 128, 3.5f, 0, pdwAdjacency, NULL, NULL, NULL, NULL, NULL, 0, &pMesh, &pFacePartitioning, &pVertexRemapArray, &resultStretch, &numCharts ); if( SUCCEEDED( hr ) ) { // release and set mesh SAFE_RELEASE( g_pMesh ); g_pMesh = pMesh; // write mesh to file hr = D3DXSaveMeshToX( L"cube4.x", g_pMesh, 0, ( const D3DXMATERIAL* )pMaterialBuffer->GetBufferPointer(), NULL, dwcMaterials, D3DXF_FILEFORMAT_TEXT ); if( FAILED( hr ) ) { DebugStringDX( "Main", "Failed to D3DXSaveMeshToX() at OnD3D9CreateDevice()", __LINE__, hr ); } // fill the the light map hr = BuildLightmap( pS, g_pMesh ); if( FAILED( hr ) ) { DebugStringDX( "Main", "Failed to BuildLightmap()", __LINE__, hr ); } } else { DebugStringDX( "Main", "Failed to D3DXUVAtlasCreate() at OnD3D9CreateDevice()", __LINE__, hr ); } SAFE_RELEASE( pS ); SAFE_DELETE_ARRAY( pdwAdjacency ); SAFE_RELEASE( pFacePartitioning ); SAFE_RELEASE( pVertexRemapArray ); SAFE_RELEASE( pMaterialBuffer ); Here is code to fill lightmap texture: HRESULT BuildLightmap( IDirect3DSurface9 *pS, LPD3DXMESH pMesh ) { HRESULT hr = S_OK; // validate lightmap texture surface and mesh if( !pS || !pMesh ) return E_POINTER; // lock the mesh vertex buffer sVertexPosNormTex *pV = NULL; pMesh->LockVertexBuffer( D3DLOCK_READONLY, ( void** )&pV ); // lock the mesh index buffer WORD *pI = NULL; pMesh->LockIndexBuffer( D3DLOCK_READONLY, ( void** )&pI ); // get the lightmap texture surface description D3DSURFACE_DESC desc; pS->GetDesc( &desc ); // lock the surface rect to fill with color data D3DLOCKED_RECT rct; hr = pS->LockRect( &rct, NULL, 0 ); if( FAILED( hr ) ) { DebugStringDX( "main.cpp:", "Failed to IDirect3DTexture9::LockRect()", __LINE__, hr ); return hr; } // iterate the pixels of the lightmap texture // check each pixel to see if it lies between the uv coordinates of a cube face BYTE *pBuffer = ( BYTE* )rct.pBits; for( UINT y = 0; y < desc.Height; ++y ) { BYTE* pBufferRow = ( BYTE* )pBuffer; for( UINT x = 0; x < desc.Width * 4; x+=4 ) { // determine the pixel's uv coordinate D3DXVECTOR2 p( ( ( float )x / 4.0f ) / ( float )desc.Width + 0.5f / 128.0f, y / ( float )desc.Height + 0.5f / 128.0f ); // for each face of the mesh // check to see if the pixel lies within the face's uv coordinates for( UINT i = 0; i < 3 * pMesh->GetNumFaces(); i +=3 ) { sVertexPosNormTex v[ 3 ]; v[ 0 ] = pV[ pI[ i + 0 ] ]; v[ 1 ] = pV[ pI[ i + 1 ] ]; v[ 2 ] = pV[ pI[ i + 2 ] ]; if( TexcoordIsWithinBounds( v[ 0 ].vUV, v[ 1 ].vUV, v[ 2 ].vUV, p ) ) { // the pixel lies b/t the uv coordinates of a cube face // light contribution functions aren't needed yet //D3DXVECTOR3 vPos = TexcoordToPos( v[ 0 ].vPos, v[ 1 ].vPos, v[ 2 ].vPos, v[ 0 ].vUV, v[ 1 ].vUV, v[ 2 ].vUV, p ); //D3DXVECTOR3 vNormal = v[ 0 ].vNorm; // set the color of this pixel red( for demo ) BYTE ba[] = { 0, 0, 255, 255, }; //ComputeContribution( vPos, vNormal, g_sLight, ba ); // copy the byte array into the light map texture memcpy( ( void* )&pBufferRow[ x ], ( void* )ba, 4 * sizeof( BYTE ) ); } } } // go to next line of the texture pBuffer += rct.Pitch; } // unlock the surface rect pS->UnlockRect(); // unlock mesh vertex and index buffers pMesh->UnlockIndexBuffer(); pMesh->UnlockVertexBuffer(); // write the surface to file hr = D3DXSaveSurfaceToFile( L"LightMap.jpg", D3DXIFF_JPG, pS, NULL, NULL ); if( FAILED( hr ) ) DebugStringDX( "Main.cpp", "Failed to D3DXSaveSurfaceToFile()", __LINE__, hr ); return hr; } bool TexcoordIsWithinBounds( const D3DXVECTOR2 &t0, const D3DXVECTOR2 &t1, const D3DXVECTOR2 &t2, const D3DXVECTOR2 &p ) { // compute vectors D3DXVECTOR2 v0 = t1 - t0, v1 = t2 - t0, v2 = p - t0; float f00 = D3DXVec2Dot( &v0, &v0 ); float f01 = D3DXVec2Dot( &v0, &v1 ); float f02 = D3DXVec2Dot( &v0, &v2 ); float f11 = D3DXVec2Dot( &v1, &v1 ); float f12 = D3DXVec2Dot( &v1, &v2 ); // Compute barycentric coordinates float invDenom = 1 / ( f00 * f11 - f01 * f01 ); float fU = ( f11 * f02 - f01 * f12 ) * invDenom; float fV = ( f00 * f12 - f01 * f02 ) * invDenom; // Check if point is in triangle if( ( fU >= 0 ) && ( fV >= 0 ) && ( fU + fV < 1 ) ) return true; return false; } Screenshot Lightmap I believe the problem comes from the difference between the lightmap uv coordinates and the pixel center coordinates...for example, here are the lightmap uv coordinates( generated by D3DXUVAtlasCreate() ) for a specific face( tri ) within the mesh, keep in mind that I'm using the mesh uv coordinates to write the pixels for the texture: v[ 0 ].uv = D3DXVECTOR2( 0.003581, 0.295631 ); v[ 1 ].uv = D3DXVECTOR2( 0.003581, 0.003581 ); v[ 2 ].uv = D3DXVECTOR2( 0.295631, 0.003581 ); the lightmap texture size is 128 x 128 pixels. The upper-left pixel center coordinates are: float halfPixel = 0.5 / 128 = 0.00390625; D3DXVECTOR2 pixelCenter = D3DXVECTOR2( halfPixel, halfPixel ); will the mapping and sampling of the lightmap texture will require that an offset be taken into account or that the uv coordinates are snapped to the pixel centers..? ...Any ideas on the best way to approach this situation would be appreciated...What are the common practices?

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  • C++ FBX Animation Importer Using the FBX SDK

    - by Mike Sawayda
    Does anyone have any experience using the FBX SDK to load in animations. I got the meshes loaded in correctly with all of their verts, indices, UV's, and normals. I am just now trying to get the Animations working correctly. I have looked at the FBX SDK documentation with little help. If someone could just help me get started or point me in the right direction I would greatly appreciate it. I added some code so you can kinda get an idea of what I am doing. I should be able to place that code anywhere in the load FBX function and have it work. //GETTING ANIMAION DATA for(int i = 0; i < scene->GetSrcObjectCount<FbxAnimStack>(); ++i) { FbxAnimStack* lAnimStack = scene->GetSrcObject<FbxAnimStack>(i); FbxString stackName = "Animation Stack Name: "; stackName += lAnimStack->GetName(); string sStackName = stackName; int numLayers = lAnimStack->GetMemberCount<FbxAnimLayer>(); for(int j = 0; j < numLayers; ++j) { FbxAnimLayer* lAnimLayer = lAnimStack->GetMember<FbxAnimLayer>(j); FbxString layerName = "Animation Stack Name: "; layerName += lAnimLayer->GetName(); string sLayerName = layerName; queue<FbxNode*> nodes; FbxNode* tempNode = scene->GetRootNode(); while(tempNode != NULL) { FbxAnimCurve* lAnimCurve = tempNode->LclTranslation.GetCurve(lAnimLayer, FBXSDK_CURVENODE_COMPONENT_X); if(lAnimCurve != NULL) { //I know something needs to be done here but I dont know what. } for(int i = 0; i < tempNode->GetChildCount(false); ++i) { nodes.push(tempNode->GetChild(i)); } if(nodes.size() > 0) { tempNode = nodes.front(); nodes.pop(); } else { tempNode = NULL; } } } } Here is the full function bool FBXLoader::LoadFBX(ParentMeshObject* _parentMesh, char* _filePath, bool _hasTexture) { FbxManager* fbxManager = FbxManager::Create(); if(!fbxManager) { printf( "ERROR %s : %d failed creating FBX Manager!\n", __FILE__, __LINE__ ); } FbxIOSettings* ioSettings = FbxIOSettings::Create(fbxManager, IOSROOT); fbxManager->SetIOSettings(ioSettings); FbxString filePath = FbxGetApplicationDirectory(); fbxManager->LoadPluginsDirectory(filePath.Buffer()); FbxScene* scene = FbxScene::Create(fbxManager, ""); int fileMinor, fileRevision; int sdkMajor, sdkMinor, sdkRevision; int fileFormat; FbxManager::GetFileFormatVersion(sdkMajor, sdkMinor, sdkRevision); FbxImporter* importer = FbxImporter::Create(fbxManager, ""); if(!fbxManager->GetIOPluginRegistry()->DetectReaderFileFormat(_filePath, fileFormat)) { //Unrecognizable file format. Try to fall back on FbxImorter::eFBX_BINARY fileFormat = fbxManager->GetIOPluginRegistry()->FindReaderIDByDescription("FBX binary (*.fbx)"); } bool importStatus = importer->Initialize(_filePath, fileFormat, fbxManager->GetIOSettings()); importer->GetFileVersion(fileMinor, fileMinor, fileRevision); if(!importStatus) { printf( "ERROR %s : %d FbxImporter Initialize failed!\n", __FILE__, __LINE__ ); return false; } importStatus = importer->Import(scene); if(!importStatus) { printf( "ERROR %s : %d FbxImporter failed to import the file to the scene!\n", __FILE__, __LINE__ ); return false; } FbxAxisSystem sceneAxisSystem = scene->GetGlobalSettings().GetAxisSystem(); FbxAxisSystem axisSystem( FbxAxisSystem::eYAxis, FbxAxisSystem::eParityOdd, FbxAxisSystem::eLeftHanded ); if(sceneAxisSystem != axisSystem) { axisSystem.ConvertScene(scene); } TriangulateRecursive(scene->GetRootNode()); FbxArray<FbxMesh*> meshes; FillMeshArray(scene, meshes); unsigned short vertexCount = 0; unsigned short triangleCount = 0; unsigned short faceCount = 0; unsigned short materialCount = 0; int numberOfVertices = 0; for(int i = 0; i < meshes.GetCount(); ++i) { numberOfVertices += meshes[i]->GetPolygonVertexCount(); } Face face; vector<Face> faces; int indicesCount = 0; int ptrMove = 0; float wValue = 0.0f; if(!_hasTexture) { wValue = 1.0f; } for(int i = 0; i < meshes.GetCount(); ++i) { int vertexCount = 0; vertexCount = meshes[i]->GetControlPointsCount(); if(vertexCount == 0) continue; VertexType* vertices; vertices = new VertexType[vertexCount]; int triangleCount = meshes[i]->GetPolygonVertexCount() / 3; indicesCount = meshes[i]->GetPolygonVertexCount(); FbxVector4* fbxVerts = new FbxVector4[vertexCount]; int arrayIndex = 0; memcpy(fbxVerts, meshes[i]->GetControlPoints(), vertexCount * sizeof(FbxVector4)); for(int j = 0; j < triangleCount; ++j) { int index = 0; FbxVector4 fbxNorm(0, 0, 0, 0); FbxVector2 fbxUV(0, 0); bool texCoordFound = false; face.indices[0] = index = meshes[i]->GetPolygonVertex(j, 0); vertices[index].position.x = (float)fbxVerts[index][0]; vertices[index].position.y = (float)fbxVerts[index][1]; vertices[index].position.z = (float)fbxVerts[index][2]; vertices[index].position.w = wValue; meshes[i]->GetPolygonVertexNormal(j, 0, fbxNorm); vertices[index].normal.x = (float)fbxNorm[0]; vertices[index].normal.y = (float)fbxNorm[1]; vertices[index].normal.z = (float)fbxNorm[2]; texCoordFound = meshes[i]->GetPolygonVertexUV(j, 0, "map1", fbxUV); vertices[index].texture.x = (float)fbxUV[0]; vertices[index].texture.y = (float)fbxUV[1]; face.indices[1] = index = meshes[i]->GetPolygonVertex(j, 1); vertices[index].position.x = (float)fbxVerts[index][0]; vertices[index].position.y = (float)fbxVerts[index][1]; vertices[index].position.z = (float)fbxVerts[index][2]; vertices[index].position.w = wValue; meshes[i]->GetPolygonVertexNormal(j, 1, fbxNorm); vertices[index].normal.x = (float)fbxNorm[0]; vertices[index].normal.y = (float)fbxNorm[1]; vertices[index].normal.z = (float)fbxNorm[2]; texCoordFound = meshes[i]->GetPolygonVertexUV(j, 1, "map1", fbxUV); vertices[index].texture.x = (float)fbxUV[0]; vertices[index].texture.y = (float)fbxUV[1]; face.indices[2] = index = meshes[i]->GetPolygonVertex(j, 2); vertices[index].position.x = (float)fbxVerts[index][0]; vertices[index].position.y = (float)fbxVerts[index][1]; vertices[index].position.z = (float)fbxVerts[index][2]; vertices[index].position.w = wValue; meshes[i]->GetPolygonVertexNormal(j, 2, fbxNorm); vertices[index].normal.x = (float)fbxNorm[0]; vertices[index].normal.y = (float)fbxNorm[1]; vertices[index].normal.z = (float)fbxNorm[2]; texCoordFound = meshes[i]->GetPolygonVertexUV(j, 2, "map1", fbxUV); vertices[index].texture.x = (float)fbxUV[0]; vertices[index].texture.y = (float)fbxUV[1]; faces.push_back(face); } meshes[i]->Destroy(); meshes[i] = NULL; int indexCount = faces.size() * 3; unsigned long* indices = new unsigned long[faces.size() * 3]; int indicie = 0; for(unsigned int i = 0; i < faces.size(); ++i) { indices[indicie++] = faces[i].indices[0]; indices[indicie++] = faces[i].indices[1]; indices[indicie++] = faces[i].indices[2]; } faces.clear(); _parentMesh->AddChild(vertices, indices, vertexCount, indexCount); } return true; }

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  • FreeType2 Bitmap to System::Drawing::Bitmap.

    - by Dennis Roche
    Hi, I'm trying to convert a FreeType2 bitmap to a System::Drawing::Bitmap in C++/CLI. FT_Bitmap has a unsigned char* buffer that contains the data to write. I have got somewhat working save it disk as a *.tga, but when saving as *.bmp it renders incorrectly. I believe that the size of byte[] is incorrect and that my data is truncated. Any hints/tips/ideas on what is going on here would be greatly appreciated. Links to articles explaining byte layout and pixel formats etc. would be helpful. Thanks!! C++/CLI code. FT_Bitmap *bitmap = &face->glyph->bitmap; int width = (face->bitmap->metrics.width / 64); int height = (face->bitmap->metrics.height / 64); // must be aligned on a 32 bit boundary or 4 bytes int depth = 8; int stride = ((width * depth + 31) & ~31) >> 3; int bytes = (int)(stride * height); // as *.tga void *buffer = bytes ? malloc(bytes) : NULL; if (buffer) { memset(buffer, 0, bytes); for (int i = 0; i < glyph->rows; ++i) memcpy((char *)buffer + (i * width), glyph->buffer + (i * glyph->pitch), glyph->pitch); WriteTGA("Test.tga", buffer, width, height); } array<Byte>^ values = gcnew array<Byte>(bytes); Marshal::Copy((IntPtr)glyph->buffer, values, 0, bytes); // as *.bmp Bitmap^ systemBitmap = gcnew Bitmap(width, height, PixelFormat::Format24bppRgb); // create bitmap data, lock pixels to be written. BitmapData^ bitmapData = systemBitmap->LockBits(Rectangle(0, 0, width, height), ImageLockMode::WriteOnly, bitmap->PixelFormat); Marshal::Copy(values, 0, bitmapData->Scan0, bytes); systemBitmap->UnlockBits(bitmapData); systemBitmap->Save("Test.bmp"); Reference, FT_Bitmap typedef struct FT_Bitmap_ { int rows; int width; int pitch; unsigned char* buffer; short num_grays; char pixel_mode; char palette_mode; void* palette; } FT_Bitmap; Reference, WriteTGA bool WriteTGA(const char *filename, void *pxl, uint16 width, uint16 height) { FILE *fp = NULL; fopen_s(&fp, filename, "wb"); if (fp) { TGAHeader header; memset(&header, 0, sizeof(TGAHeader)); header.imageType = 3; header.width = width; header.height = height; header.depth = 8; header.descriptor = 0x20; fwrite(&header, sizeof(header), 1, fp); fwrite(pxl, sizeof(uint8) * width * height, 1, fp); fclose(fp); return true; } return false; }

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  • unsigned char* buffer (FreeType2 Bitmap) to System::Drawing::Bitmap.

    - by Dennis Roche
    Hi, I'm trying to convert a FreeType2 bitmap to a System::Drawing::Bitmap in C++/CLI. FT_Bitmap has a unsigned char* buffer that contains the data to write. I have got somewhat working save it disk as a *.tga, but when saving as *.bmp it renders incorrectly. I believe that the size of byte[] is incorrect and that my data is truncated. Any hints/tips/ideas on what is going on here would be greatly appreciated. Links to articles explaining byte layout and pixel formats etc. would be helpful. Thanks!! C++/CLI code. FT_Bitmap *bitmap = &face->glyph->bitmap; int width = (face->bitmap->metrics.width / 64); int height = (face->bitmap->metrics.height / 64); // must be aligned on a 32 bit boundary or 4 bytes int depth = 8; int stride = ((width * depth + 31) & ~31) >> 3; int bytes = (int)(stride * height); // as *.tga void *buffer = bytes ? malloc(bytes) : NULL; if (buffer) { memset(buffer, 0, bytes); for (int i = 0; i < glyph->rows; ++i) memcpy((char *)buffer + (i * width), glyph->buffer + (i * glyph->pitch), glyph->pitch); WriteTGA("Test.tga", buffer, width, height); } // as *.bmp array<Byte>^ values = gcnew array<Byte>(bytes); Marshal::Copy((IntPtr)glyph->buffer, values, 0, bytes); Bitmap^ systemBitmap = gcnew Bitmap(width, height, PixelFormat::Format24bppRgb); // create bitmap data, lock pixels to be written. BitmapData^ bitmapData = systemBitmap->LockBits(Rectangle(0, 0, width, height), ImageLockMode::WriteOnly, bitmap->PixelFormat); Marshal::Copy(values, 0, bitmapData->Scan0, bytes); systemBitmap->UnlockBits(bitmapData); systemBitmap->Save("Test.bmp"); Reference, FT_Bitmap typedef struct FT_Bitmap_ { int rows; int width; int pitch; unsigned char* buffer; short num_grays; char pixel_mode; char palette_mode; void* palette; } FT_Bitmap; Reference, WriteTGA bool WriteTGA(const char *filename, void *pxl, uint16 width, uint16 height) { FILE *fp = NULL; fopen_s(&fp, filename, "wb"); if (fp) { TGAHeader header; memset(&header, 0, sizeof(TGAHeader)); header.imageType = 3; header.width = width; header.height = height; header.depth = 8; header.descriptor = 0x20; fwrite(&header, sizeof(header), 1, fp); fwrite(pxl, sizeof(uint8) * width * height, 1, fp); fclose(fp); return true; } return false; } Update FT_Bitmap *bitmap = &face->glyph->bitmap; // stride must be aligned on a 32 bit boundary or 4 bytes int depth = 8; int stride = ((width * depth + 31) & ~31) >> 3; int bytes = (int)(stride * height); target = gcnew Bitmap(width, height, PixelFormat::Format8bppIndexed); // create bitmap data, lock pixels to be written. BitmapData^ bitmapData = target->LockBits(Rectangle(0, 0, width, height), ImageLockMode::WriteOnly, target->PixelFormat); array<Byte>^ values = gcnew array<Byte>(bytes); Marshal::Copy((IntPtr)bitmap->buffer, values, 0, bytes); Marshal::Copy(values, 0, bitmapData->Scan0, bytes); target->UnlockBits(bitmapData);

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  • packet mmap send packet format

    - by SeregASM
    I want to improve packet transmitting performance. Before that I used raw sockets and now I study packet_mmap. I have packets(frames) which I already captured from kernel module from another PC, put to current PC and now I want to retransmit them to local interface with following forwarding. I have got example of packet_mmap, integrated it to my project, but I send fd_socket = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL)); memset(&my_addr, 0, sizeof(struct sockaddr_ll)); my_addr.sll_family = PF_PACKET; my_addr.sll_protocol = htons(ETH_P_ALL); strcpy(str_devname, "eth0"); strncpy(s_ifr.ifr_name, str_devname, sizeof(s_ifr.ifr_name)); ec = ioctl(fd_socket, SIOCGIFINDEX, &s_ifr); i_ifindex = s_ifr.ifr_ifindex; memset(&my_addr, 0, sizeof(struct sockaddr_ll)); my_addr.sll_family = AF_PACKET; my_addr.sll_protocol = ETH_P_ALL; my_addr.sll_ifindex = i_ifindex; bind(fd_socket, (struct sockaddr *) &my_addr, sizeof(struct sockaddr_ll) s_packet_req.tp_block_size = c_buffer_sz; s_packet_req.tp_frame_size = c_buffer_sz; s_packet_req.tp_block_nr = c_buffer_nb; s_packet_req.tp_frame_nr = c_buffer_nb; size = s_packet_req.tp_block_size * s_packet_req.tp_block_nr; if (setsockopt(fd_socket, SOL_PACKET, PACKET_TX_RING, (char *) &s_packet_req, sizeof(s_packet_req)) < 0) { perror("setsockopt: PACKET_TX_RING"); return; } if (c_sndbuf_sz) { printf("send buff size = %d\n", c_sndbuf_sz); if (setsockopt(fd_socket, SOL_SOCKET, SO_SNDBUF, &c_sndbuf_sz, sizeof(c_sndbuf_sz)) < 0){ perror("getsockopt: SO_SNDBUF"); exit(1); } } data_offset = TPACKET_HDRLEN - sizeof(struct sockaddr_ll); printf("data offset = %d bytes\n", data_offset); ps_header_start = (tpacket_hdr *) mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd_socket, 0); if (ps_header_start == (void*) -1) { perror("mmap"); exit(1); } Then I fill data ps_header = ((struct tpacket_hdr *) ((char *) ps_header_start + (c_buffer_sz * i_index))); if (!ps_header) { perror("ps_header") ; return NULL; } data = ((char*) ps_header) + data_offset; switch ((volatile uint32_t) ps_header->tp_status) { case TP_STATUS_AVAILABLE: printf("TP_STATUS_AVAILABLE, index=%d\n",i_index) ; memcpy(data, packet_data, size); pthread_mutex_lock(&index_locker) ; i_index++; pthread_mutex_unlock(&index_locker) ; if (i_index >= c_buffer_nb) { i_index = 0; first_loop = 0; } /* update packet len */ ps_header->tp_len = size; /* set header flag to USER (trigs xmit)*/ ps_header->tp_status = TP_STATUS_SEND_REQUEST; then I send ec_send = sendto(fd_socket, NULL, 0, 0, (struct sockaddr *) ps_sockaddr, sizeof(struct sockaddr_ll)); I have got no errors, ec_send=not null size of sended data. But there are no data routed to destination host. So, I ask - what data I should pass to ring buffer, now I include headers ip,tcp, should I include MAC header? - May be I have to set additional flags to route my packets.

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  • Multidimensional array problem in VHDL?

    - by Nektarios
    I'm trying to use a multidimensional array in VHDL and I'm having a lot of trouble getting it to work properly. My issue is that I've got an array of 17, of 16 vectors, of a given size. What I want to do is create 17 registers that are array of 16 * std_logic_vector of 32 bits (which = my b, 512). So, I'm trying to pass in something to input and output on the register instantiation that tells the compiler/synthesizer that I want to pass in something that is 512 bits worth... Similar to in C if I had: int var[COLS][ROWS][ELEMENTS]; memcpy(&var[3].. // I'm talking about 3rd COL here, passing in memory that is ROWS*ELEMENTS long (My actual declaration is here:) type partial_pipeline_registers_type is array (0 to 16, 0 to 15) of std_logic_vector(iw - 1 downto 0); signal h_blk_pipelined_input : partial_pipeline_registers_type; I tried simply using h_blk_pipelined_input(0) .. up to (16) but this doesn't work. I get the following error, which makes me see that I need to double index in to the array: ERROR:HDLParsers:821 - (at the register) Wrong index type for h_blk_pipelined_input. So then I tried what's below, and I get this error: ERROR:HDLParsers:164 - (at the register code). parse error, unexpected TO, expecting COMMA or CLOSEPAR instantiate_h_pipelined_reg : regn generic map ( N=> b, init => bzeros ) port map ( clk => clk , rst => '0', en => '1', input => h_blk_pipelined_input((i - 1), 0 to 15), output=> h_blk_pipelined_input((i), 0 to 15)); -- Changing 0 to 15 to (0 to 15) has no effect... I'm using XST, and from their documentation (http://www.xilinx.com/itp/xilinx6/books/data/docs/xst/xst0067_9.html), the above should have worked: ...declaration: subtype MATRIX15 is array(4 downto 0, 2 downto 0) of STD_LOGIC_VECTOR (7 downto 0); A multi-dimensional array signal or variable can be completely used: Just a slice of one row can be specified: MATRIX15 (4,4 downto 1) <= TAB_B (3 downto 0); One alternative is that I can create more registers that are 16 times smaller, and instead of trying to do all '0 to 15' at once, I would just do that 15 additional times. However, I think this may lead to inefficiency in synthesis and I don't feel like this is the right solution. EDIT: Tried what Ben said, instantiate_h_m_qa_pipeline_registers: for i in 1 to 16 generate instantiate_h_pipelined_reg : regn generic map ( N=> b, init => bzeros ) port map ( clk => clk , rst => '0', en => '1', input => h_blk_pipelined_input(i - 1), output=> h_blk_pipelined_input(i)); end generate instantiate_h_m_qa_pipeline_registers; The signals are now defined as: type std_logic_block is array (0 to 15) of std_logic_vector(iw - 1 downto 0) ; type partial_pipeline_registers_type is array (0 to 16) of std_logic_block; signal h_blk_pipelined_input : partial_pipeline_registers_type; And the error I get from XST is: ERROR:HDLParsers:800 - ((where the register part is)) Type of input is incompatible with type of h_blk_pipelined_input. I'm able to do everything I was able to do before, using ()() syntax instead of ( , ) so I haven't lost anything going this way, but it still doesn't resolve my problem.

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  • weighted RNG speed problem in C++

    - by supert
    I have a (fast) bit of C++ code that samples cards from a 52 card deck: void sample_allcards(int table[5], int holes[], int players) { int temp[5 + 2 * players]; bool try_again; int c, n, i; for (i = 0; i < 5 + 2 * players; i++) { try_again = true; while (try_again == true) { try_again = false; c = fast_rand52(); // reject collisions for (n = 0; n < i + 1; n++) { try_again = (temp[n] == c) || try_again; } temp[i] = c; } } copy_cards(table, temp, 5); copy_cards(holes, temp + 5, 2 * players); } I am implementing code to sample the hole cards according to a known distribution (stored as a 2d table). My code for this looks like: void sample_allcards_weighted(double weights[][HOLE_CARDS], int table[5], int holes[], int players) { // weights are distribution over hole cards int temp[5 + 2 * players]; int n, i; // table cards for (i = 0; i < 5; i++) { bool try_again = true; while (try_again == true) { try_again = false; int c = fast_rand52(); // reject collisions for (n = 0; n < i + 1; n++) { try_again = (temp[n] == c) || try_again; } temp[i] = c; } } for (int player = 0; player < players; player++) { // hole cards according to distribution i = 5 + 2 * player; bool try_again = true; while (try_again == true) { try_again = false; // weighted-sample c1 and c2 at once double w[1326]; memcpy(w, weights[player], sizeof(w)); // h is a number < 1325 int h = weighted_randi(w, HOLE_CARDS); // i2h uses h and sets temp[i] to the 2 cards implied by h i2h(&temp[i], h); // reject collisions for (n = 0; n < i; n++) { try_again = (temp[n] == temp[i]) || (temp[n] == temp[i+1]) || try_again; } } } copy_cards(table, temp, 5); copy_cards(holes, temp + 5, 2 * players); } My problem? The weighted sampling algorithm is a factor of 10 slower. Speed is very important for my application. Is there a way to improve the speed of my algorithm to something more reasonable? Am I doing something wrong in my implementation? Thanks.

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  • Is there a library available which easily can record and replay results of API calls?

    - by Billy ONeal
    I'm working on writing various things that call relatively complicated Win32 API functions. Here's an example: //Encapsulates calling NtQuerySystemInformation buffer management. WindowsApi::AutoArray NtDll::NtQuerySystemInformation( SystemInformationClass toGet ) const { AutoArray result; ULONG allocationSize = 1024; ULONG previousSize; NTSTATUS errorCheck; do { previousSize = allocationSize; result.Allocate(allocationSize); errorCheck = WinQuerySystemInformation(toGet, result.GetAs<void>(), allocationSize, &allocationSize); if (allocationSize <= previousSize) allocationSize = previousSize * 2; } while (errorCheck == 0xC0000004L); if (errorCheck != 0) { THROW_MANUAL_WINDOWS_ERROR(WinRtlNtStatusToDosError(errorCheck)); } return result; } //Client of the above. ProcessSnapshot::ProcessSnapshot() { using Dll::NtDll; NtDll ntdll; AutoArray systemInfoBuffer = ntdll.NtQuerySystemInformation( NtDll::SystemProcessInformation); BYTE * currentPtr = systemInfoBuffer.GetAs<BYTE>(); //Loop through the results, creating Process objects. SYSTEM_PROCESSES * asSysInfo; do { // Loop book keeping asSysInfo = reinterpret_cast<SYSTEM_PROCESSES *>(currentPtr); currentPtr += asSysInfo->NextEntryDelta; //Create the process for the current iteration and fill it with data. std::auto_ptr<ProcImpl> currentProc(ProcFactory( static_cast<unsigned __int32>(asSysInfo->ProcessId), this)); NormalProcess* nptr = dynamic_cast<NormalProcess*>(currentProc.get()); if (nptr) { nptr->SetProcessName(asSysInfo->ProcessName); } // Populate process threads for(ULONG idx = 0; idx < asSysInfo->ThreadCount; ++idx) { SYSTEM_THREADS& sysThread = asSysInfo->Threads[idx]; Thread thread( currentProc.get(), static_cast<unsigned __int32>(sysThread.ClientId.UniqueThread), sysThread.StartAddress); currentProc->AddThread(thread); } processes.push_back(currentProc); } while(asSysInfo->NextEntryDelta != 0); } My problem is in mocking out the NtDll::NtQuerySystemInformation method -- namely, that the data structure returned is complicated (Well, here it's actually relatively simple but it can be complicated), and writing a test which builds the data structure like the API call does can take 5-6 times as long as writing the code that uses the API. What I'd like to do is take a call to the API, and record it somehow, so that I can return that recorded value to the code under test without actually calling the API. The returned structures cannot simply be memcpy'd, because they often contain inner pointers (pointers to other locations in the same buffer). The library in question would need to check for these kinds of things, and be able to restore pointer values to a similar buffer upon replay. (i.e. check each pointer sized value if it could be interpreted as a pointer within the buffer, change that to an offset, and remember to change it back to a pointer on replay -- a false positive rate here is acceptable) Is there anything out there that does anything like this?

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  • How can I return an object into PHP userspace from my extension?

    - by John Factorial
    I have a C++ object, Graph, which contains a property named cat of type Category. I'm exposing the Graph object to PHP in an extension I'm writing in C++. As long as the Graph's methods return primitives like boolean or long, I can use the Zend RETURN_*() macros (e.g. RETURN_TRUE(); or RETURN_LONG(123);. But how can I make Graph-getCategory(); return a Category object for the PHP code to manipulate? I'm following the tutorial over at http://devzone.zend.com/article/4486, and here's the Graph code I have so far: #include "php_getgraph.h" zend_object_handlers graph_object_handlers; struct graph_object { zend_object std; Graph *graph; }; zend_class_entry *graph_ce; #define PHP_CLASSNAME "WFGraph" ZEND_BEGIN_ARG_INFO_EX(php_graph_one_arg, 0, 0, 1) ZEND_END_ARG_INFO() ZEND_BEGIN_ARG_INFO_EX(php_graph_two_args, 0, 0, 2) ZEND_END_ARG_INFO() void graph_free_storage(void *object TSRMLS_DC) { graph_object *obj = (graph_object*)object; delete obj-graph; zend_hash_destroy(obj-std.properties); FREE_HASHTABLE(obj-std.properties); efree(obj); } zend_object_value graph_create_handler(zend_class_entry *type TSRMLS_DC) { zval *tmp; zend_object_value retval; graph_object *obj = (graph_object*)emalloc(sizeof(graph_object)); memset(obj, 0, sizeof(graph_object)); obj-std.ce = type; ALLOC_HASHTABLE(obj-std.properties); zend_hash_init(obj-std.properties, 0, NULL, ZVAL_PTR_DTOR, 0); zend_hash_copy(obj-std.properties, &type-default_properties, (copy_ctor_func_t)zval_add_ref, (void*)&tmp, sizeof(zval*)); retval.handle = zend_objects_store_put(obj, NULL, graph_free_storage, NULL TSRMLS_CC); retval.handlers = &graph_object_handlers; return retval; } PHP_METHOD(Graph, __construct) { char *perspectives; int perspectives_len; Graph *graph = NULL; zval *object = getThis(); if(zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &perspectives, &perspectives_len) == FAILURE) { RETURN_NULL(); } graph = new Graph(perspectives); graph_object *obj = (graph_object*)zend_object_store_get_object(object TSRMLS_CC); obj-graph = graph; } PHP_METHOD(Graph, hasCategory) { long perspectiveId; Graph *graph; graph_object *obj = (graph_object*)zend_object_store_get_object(getThis() TSRMLS_CC); graph = obj-graph; if (graph == NULL) { RETURN_NULL(); } if(zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "l", &perspectiveId) == FAILURE) { RETURN_NULL(); } RETURN_BOOL(graph-hasCategory(perspectiveId)); } PHP_METHOD(Graph, getCategory) { // what to do here? RETURN_TRUE; } function_entry php_getgraph_functions[] = { PHP_ME(Graph,__construct,NULL,ZEND_ACC_PUBLIC|ZEND_ACC_CTOR) PHP_ME(Graph,hasCategory,php_graph_one_arg,ZEND_ACC_PUBLIC) PHP_ME(Graph,getCategory,php_graph_one_arg,ZEND_ACC_PUBLIC) { NULL, NULL, NULL } }; PHP_MINIT_FUNCTION(getgraph) { zend_class_entry ce; INIT_CLASS_ENTRY(ce, PHP_CLASSNAME, php_getgraph_functions); graph_ce = zend_register_internal_class(&ce TSRMLS_CC); graph_ce-create_object = graph_create_handler; memcpy(&graph_object_handlers, zend_get_std_object_handlers(), sizeof(zend_object_handlers)); graph_object_handlers.clone_obj = NULL; return SUCCESS; } zend_module_entry getgraph_module_entry = { #if ZEND_MODULE_API_NO = 20010901 STANDARD_MODULE_HEADER, #endif PHP_GETGRAPH_EXTNAME, NULL, /* Functions */ PHP_MINIT(getgraph), NULL, /* MSHUTDOWN */ NULL, /* RINIT */ NULL, /* RSHUTDOWN */ NULL, /* MINFO */ #if ZEND_MODULE_API_NO = 20010901 PHP_GETGRAPH_EXTVER, #endif STANDARD_MODULE_PROPERTIES }; #ifdef COMPILE_DL_GETGRAPH extern "C" { ZEND_GET_MODULE(getgraph) } #endif

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  • Strange thing on IPv6 multicast program on Windows

    - by zhanglistar
    I have written an ipv6 multicast program on windows xp sp3. But a problem bothers me a lot. The sendto function implies no error, but I can't capture the packet using wireshark. I am sure the filter is right. Thanks in advance. And the code is as follows: #include "stdafx.h" #include <stdio.h> /* for printf() and fprintf() */ #include <winsock2.h> /* for socket(), connect(), sendto(), and recvfrom() */ #include <ws2tcpip.h> /* for ip_mreq */ #include <stdlib.h> /* for atoi() and exit() */ #include <string.h> /* for memset() */ #include <time.h> /* for timestamps */ #include <pcap.h> #include <Iphlpapi.h> #pragma comment(lib, "Ws2_32.lib") #pragma comment(lib, "wpcap.lib") #pragma comment(lib, "Iphlpapi.lib") int _tmain(int argc, _TCHAR* argv[]) { int sfd; int on, length, iResult; WSADATA wsaData; struct addrinfo Hints; struct addrinfo *multicastAddr, *localAddr; char buf[46]; // Initialize Winsock iResult = WSAStartup(MAKEWORD(2, 2), &wsaData); if (iResult != 0) { printf("WSAStartup failed: %d\n", iResult); return 1; } /* Resolve destination address for multicast datagrams */ memset(&Hints, 0, sizeof (Hints)); Hints.ai_family = AF_INET6; Hints.ai_socktype = SOCK_DGRAM; Hints.ai_protocol = IPPROTO_UDP; Hints.ai_flags = AI_NUMERICHOST; iResult = getaddrinfo("FF02::1:2", "547", &Hints, &multicastAddr); if (iResult != 0) { /* error handling */ printf("socket error: %d\n", WSAGetLastError()); return -1; } /* Get a local address with the same family (IPv4 or IPv6) as our multicast group */ Hints.ai_family = multicastAddr->ai_family; Hints.ai_socktype = SOCK_DGRAM; Hints.ai_flags = AI_PASSIVE; /* Return an address we can bind to */ if ( getaddrinfo(NULL, "546", &Hints, &localAddr) != 0 ) { printf("getaddrinfo() failed: %d\n", WSAGetLastError()); exit(-1); } // Create sending socket //sfd = socket (multicastAddr->ai_family, multicastAddr->ai_socktype, multicastAddr->ai_protocol); sfd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP); if (sfd == -1) { printf("socket error: %d\n", WSAGetLastError()); return 0; } /* Bind to the multicast port */ if ( bind(sfd, localAddr->ai_addr, localAddr->ai_addrlen) != 0 ) { printf("bind() failed: %d\n", WSAGetLastError()); exit(-1); } if (multicastAddr->ai_family == AF_INET6 && multicastAddr->ai_addrlen == sizeof(struct sockaddr_in6)) /* IPv6 */ { on = 1; if (setsockopt (sfd, IPPROTO_IPV6, IPV6_MULTICAST_IF, (char *)&on, sizeof (on) /*(char *)&interface_addr, sizeof(interface_addr)*/) == -1) { printf("setsockopt error:%d\n", WSAGetLastError()); return -1; } if (setsockopt (sfd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, (char *)&on, sizeof (on) /*(char *)&interface_addr, sizeof(interface_addr)*/) == -1) { printf("setsockopt error:%d\n", WSAGetLastError()); return -1; } struct ipv6_mreq multicastRequest; /* Multicast address join structure */ /* Specify the multicast group */ memcpy(&multicastRequest.ipv6mr_multiaddr, &((struct sockaddr_in6*)(multicastAddr->ai_addr))->sin6_addr, sizeof(struct in6_addr)); /* Accept multicast from any interface */ multicastRequest.ipv6mr_interface = 0; /* Join the multicast address */ if ( setsockopt(sfd, IPPROTO_IPV6, IPV6_JOIN_GROUP, (char*) &multicastRequest, sizeof(multicastRequest)) != 0 ) { printf("setsockopt() failed: %d\n", WSAGetLastError()); return -1; } on = 1; if (setsockopt (sfd, IPPROTO_IPV6, IPV6_MULTICAST_IF, (char *)&on, sizeof (on)) == -1) { printf("setsockopt error:%d\n", WSAGetLastError()); return 0; } } memset(buf, 0, sizeof(buf)); strcpy(buf, "hello world"); iResult = sendto(sfd, buf, strlen(buf), 0, (LPSOCKADDR) multicastAddr->ai_addr, multicastAddr->ai_addrlen); if (iResult == SOCKET_ERROR) { printf("setsockopt error:%d\n", WSAGetLastError()); return -1; /* Error handling */ } return 0; }

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