Thread: Loading a Bitmap resource for OpenGL Texture[x]

I have been using this function to load Bitmaps for Textures in my OpenGL applications, taken from NeHe's tutorial:

Code:

AUX_RGBImageRec *LoadBMP(char *Filename) // Loads A Bitmap Image
{
FILE *File=NULL; // File Handle
if (!Filename) // Make Sure A Filename Was Given
{
return NULL; // If Not Return NULL
}
File=fopen(Filename,"r"); // Check To See If The File Exists
if (File) // Does The File Exist?
{
fclose(File); // Close The Handle
return auxDIBImageLoad(Filename); // Load The Bitmap And Return A Pointer
}
return NULL; // If Load Failed Return NULL
}

I'm now dealing with a resource bitmap though, and I need something to replace Texture[0] = LoadBMP("bitmap.bmp").


I tried TextureImage[0] = auxDIBImageLoad(MAKEINTRESOURCE(IDB_BITMAP1), which compiles but the App crashes,

and TextureImage[0] = LoadImage(hInstance,MAKEINTRESOURCE(IDB_BITMAP1),I MAGE_BITMAP,0,0,LR_LOADFROMFILE);, where the compiler gives me a conversion error.

What could I use as a replacement?

Many people seen to be using this code to work with resources:

Code:

void LoadGLTextures()
{
// load bitmap from resource file
HBITMAP bitmap = LoadBitmap(GetModuleHandle(NULL), 
MAKEINTRESOURCE(IDB_BITMAP2));

// setup 24 bits bitmap structure
// works on 8 bits bitmaps also!

BITMAPINFO info;
BITMAPINFOHEADER header;
header.biSize = sizeof(BITMAPINFOHEADER); 
header.biWidth = 256; 
header.biHeight = 256; 
header.biPlanes = 1; 
header.biBitCount = 24; 
header.biCompression = BI_RGB;
header.biSizeImage = 0; 
header.biClrUsed = 0; 
header.biClrImportant = 0; 
info.bmiHeader = header;
info.bmiColors->rgbRed = NULL;
info.bmiColors->rgbGreen = NULL;
info.bmiColors->rgbBlue = NULL;
info.bmiColors->rgbReserved = NULL;

// store bitmap data in a vector
const int size = 256*256*3;
unsigned char data[size]; 
HDC hdc = GetDC(g_hWndRender);
GetDIBits(hdc, bitmap, 0, 256, &data, &info, DIB_RGB_COLORS);
ReleaseDC(g_hWndRender, hdc);

// convert from BGR to RGB
unsigned char buff;
for(int i=0; i<256*256; i++)
{
buff = data[i*3];
if(i>=3)
{
data[i*3] = data[i*3+2];
data[i*3+2] = buff;
}
}

// create one texture
glGenTextures(1, &m_texture[0]);

// select texture
glBindTexture(GL_TEXTURE_2D, m_texture[0]);

// SetTextureParameters

// generate texture
glTexImage2D(GL_TEXTURE_2D, 0, 3, 256, 256, 0, GL_RGB, GL_UNSIGNED_BYTE, &data);
}

But I'm still new to programming, and I'm having trouble figuring out how that will help me assigning the .bmp to TextureImage[], as in the non-resource code:

Code:

AUX_RGBImageRec *TextureImage[1]; // Create Storage Space For The Texture
...
TextureImage[0] = LoadBMP("bitmap.bmp)