glTexImage2D error checking

Hey I've been adding try catch blocks wherever I dynamically declare stuff. So I went back into my old Picloader.cpp:


//This is only for PNG's and JPG's.  If anything else works then it's a coincidence.
//If you try loading a file that is already in this ImageVault then funnum will just
//be set to the correct number
bool ImageVault::ImageLoader(std::string filename, GLuint &funnum)
{
  bool breturn=false;
  SDL_RWops *rwop;  //don't remember wtf this is, use it to check if an image is a jpeg
  SDL_Surface *image;
  VaultNode *temp;

  temp=imagehead;
  imagereturn=imagehead;
  //scroll to the point in the list where the file already exists or scroll all the way to the end
  while(imagereturn!=NULL&&imagereturn->imagename!=filename)
  {
    temp=imagereturn;
    imagereturn=imagereturn->imagenext;
  }

  //if(image is already in list)
  if(imagereturn!=NULL)
  {
    funnum=imagereturn->imagenum;  //set funnum to corresponding image in OpenGL land
    breturn=true;
  }
  else  //image is not in list
  {
    if(image=IMG_Load(filename.c_str()))
    {
      glGenTextures(1, &funnum);  //funnum = a number not currently corresponding to an image in OpenGL
      glBindTexture(GL_TEXTURE_2D, funnum);  //we bind funnum but this texture is empty

      //so load a texture (*image) into OpenGL and funnum will correspond to it because it's the currently bound texture
      rwop=SDL_RWFromFile(filename.c_str(),"rb");
      if(IMG_isJPG(rwop))  //if it ain't a JPG then it's a PNG        //image->pixels is what sends the SDL image
         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, image->w, image->h, 0, GL_RGB, GL_UNSIGNED_BYTE, image->pixels);
      else
         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, image->w, image->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, image->pixels);

      //magical OpenGL stuff
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

      //we are at the end of the linked list
      try
      {
        imagereturn=new VaultNode;
        if(imagehead==NULL)
          imagehead=imagereturn;
        else
          temp->imagenext=imagereturn;

        imagereturn->imagename=filename;
        imagereturn->imagenum=funnum;
        breturn=true;
      }
      catch(std::bad_alloc&)
      {
        glDeleteTextures(1,&funnum);
      }
    }
    else  //if image won't load make the GLuint 0 just like glGen Textures
    {
      funnum=0;
    }
    if(image)
      SDL_FreeSurface(image);
  }
  return breturn;
}

ImageVault is a linked list of Nodes which contain the name of an image and its OpenGL name. (a GLuint) So I put try, catch around the part where I allocate a new Node. But now I'm wondering about glTexImage2D and glTexParameteri. Should I be checking to make sure those worked correctly too? Or are they guaranteed to work as long as image=IMG_Load(filename.c_str()) worked? glTexImage2D throws a mess of different errors if it didn't work correctly, all I want to know is if it or glTexParameteri failed so I can make ImageLoader return false and not make a new Node. So... should I bother checking to see if they throw errors? They don't return anything. Should I put them in a try block and then just use catch(...) to catch any errors and then exit ImageLoader and return false? I guess if I put those two in a try block then I should put glGenTextures(1, &funnum) in a try block as well.

Topic Locked