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Member Since 07 Jan 2012
Offline Last Active Jan 18 2012 04:20 PM

Topics I've Started

iOS Phone-to-Phone Connection

16 January 2012 - 02:52 PM

I'm just starting into iOS development and was thinking of starting my first game. The first question that came to mind was whether or not I'd need a server for multiplayer. If I do, that might make things more difficult. Instead, I was hoping to find a way to use one device as a host and have the devices communicate directly. Is there a way to do this or do I have to use a server for multiplayer?

SDL/openGL Texturing Problem

07 January 2012 - 11:07 AM

I'm writing a program that needs to display a textured 32x32 square from a 32x32 section of a tilemap. I'm using sdl to divide up the tilesheet and then register each individual tile as a separate texture.The problem is that nothing renders at all. I've checked the code out a good number of times, so I was hoping someone else would spot the problem. Thanks.

struct Texture {
SDL_Surface* tex;
GLuint texHandle;
GLint colorNum;
GLenum format;
//class render holds a tilesheet and manages it
class renderer {
short width, height;
SDL_Surface* tilesheet;
std::vector<Texture*> tile;]//null will render to the screen
SDL_Surface* destination;
SDL_Surface* loadOptimized(std::string filename);
bool divideTilesheet();
//regular loaded constructor
renderer(std::string filename, SDL_Surface* udestination);
//for creating a renderer with a procedurally generated tilesheet
renderer(SDL_Surface* utilesheet, SDL_Surface* udestination);
//tilex and tiley are both zero-based, so the upper-left tile would be (0, 0)
void render(int tilex, int tiley, int locx, int locy);
[color=#282828][font=helvetica, arial, sans-serif]SDL_Surface* getResult() {return destination;}
renderer::renderer(std::string filename, SDL_Surface* udestination) {
tilesheet = loadOptimized(filename);
destination = udestination;
width = tilesheet->w/tileSize;
height = tilesheet->h/tileSize;
renderer::renderer(SDL_Surface* utilesheet, SDL_Surface* udestination) {
tilesheet = utilesheet;
destination = udestination;
width = tilesheet->w/tileSize;
height = tilesheet->h/tileSize;
bool renderer::divideTilesheet() {
//make sure we don't leave any previous tiles
for(int y = 0; y < height; y++) {
  for(int x = 0; x < width; x++) {
   SDL_Surface* newTile = NULL;
   newTile = SDL_CreateRGBSurface(0, tileSize, tileSize, 32, 0, 0, 0, 0);
   SDL_Rect clip;
   clip.x = x*tileSize;
   clip.y = y*tileSize;
   clip.w = tileSize;
   clip.h = tileSize;
   SDL_Rect dest;
   dest.x = 0;
   dest.y = 0;
   SDL_BlitSurface(tilesheet, &clip, newTile, &dest);
   //the texture is created, so now we have to register it
   Texture* newTex = new Texture();
   newTex->tex = newTile;
   newTex->colorNum = newTex->tex->format->BytesPerPixel;
   if(newTex->colorNum == 4) {
		if(newTex->tex->format->Rmask == 0x000000ff)
		 newTex->format = GL_RGBA;
		 newTex->format = GL_BGRA;
   else if(newTex->colorNum == 3) {
		if(newTex->tex->format->Rmask == 0x000000ff)
		 newTex->format = GL_RGB;
		 newTex->format = GL_BGR;
   glGenTextures(1, &(newTex->texHandle));
   glBindTexture(GL_TEXTURE_2D, newTex->texHandle);
   glTexImage2D(GL_TEXTURE_2D, 0, newTex->colorNum, newTex->tex->w, newTex->tex->h, 0, newTex->format, GL_UNSIGNED_BYTE, newTex->tex->pixels);

return true;
SDL_Surface* renderer::loadOptimized(std::string filename) {
SDL_Surface* loaded = NULL;
SDL_Surface* optimized = NULL;
loaded = SDL_LoadBMP(filename.c_str());
if(loaded != NULL) {
  optimized = SDL_DisplayFormat(loaded);
else return NULL;
return optimized;
void renderer::render(int tilex, int tiley, int locx, int locy) {
if(destination) {
  SDL_Rect dest;
  dest.x = locx;
  dest.y = locy;
  SDL_BlitSurface(tile[tiley*width + tilex]->tex, NULL, destination, &dest);
else {
  //render to the screen with opengl
  glBindTexture(GL_TEXTURE_2D, tile[tiley*width + tilex]->texHandle);
  glColor4f(1.0, 1.0, 1.0, 1.0);

   glTexCoord2f(0, 0);
   glVertex2f(float(locx), float(locy));
   glTexCoord2f(1, 0);
   glVertex2f(float(locx + tileSize), float(locy));
   glTexCoord2f(1, 1);
   glVertex2f(float(locx + tileSize), float(locy + tileSize));
   glTexCoord2f(0, 1);
   glVertex2f(float(locx), float(locy + tileSize));

I've tried using method, but that wasn't working, either; I removed it before I originally posted here. I even tried rendering a regular square without texturing just below the textured one in the code to make sure that it hadn't somehow been transformed out of the view of the screen. It rendered, but I still can't get the textured square to render at all. It won't render black, white, or any other color; I've changed the background color several times to make sure of that. I've also checked to make sure that every tile gets a texture handle and they do, which is making me think that the mistake is either with generating the tiles with SDL or with the rendering code.