(fixed)Using GIF (or 8bit BMP) as an image source for OpenGL texture question (using CImage).

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MFC

OpenGL

Texture2D

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Happy monday.

I'm trying to use a GIF or a 8 bpp BMP image image as a source for an OpenGL texture.

The code is working well for other types of image (24, 32bits image)

I'm loading the file with CImage, but I'm having problems figuring the format and type parameters of the glTexImage2D function.

Either I get a full black texture, or I get the wrong colors.

// will create black texture.
glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, imageWidth, image.GetHeight(), 0, GL_COLOR_INDEX, GL_UNSIGNED_BYTE, bits );

// will create greyscale image.
glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, imageWidth, image.GetHeight(), 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, bits );

// will create texture with wrong colors.
glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, imageWidth, image.GetHeight(), 0, GL_RGB, GL_UNSIGNED_BYTE_3_3_2, bits );


I also tried different other combinations, either it crashes, or give the same bad results.

This is the code I have right now:

CImage image;
image.Load(fileName);

// some image info.
int imageBPP = image.GetBPP();

GLuint  texture = 0;
glGenTextures(1, &texture);
glBindTexture( GL_TEXTURE_2D, texture );

BYTE* bits = static_cast<BYTE*>(image.GetBits());
// The bitmap is a bottom-up DIB, move to the start address of the image data
bits += (imageHeight-1) * imagePitch;

if ( imageBPP == 32 )
{
    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, imageWidth, imageHeight, 0, GL_BGRA, GL_UNSIGNED_BYTE, bits );
}
else if ( imageBPP == 24 )
{
    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, imageWidth, imageHeight, 0, GL_BGR, GL_UNSIGNED_BYTE, bits );
}
else if (imageBPP==8)
{
    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, image.GetWidth(), image.GetHeight(), 0, ????, ????, bits );
}
else
{
// ... error code.
}

Any Idea ?

Thanks

Max.

==========================
Following nv3 suggestion, I decided to convert the 8 bits image to a workable image.

Thanks.