Problem with OpenGL apps on Mac 10.6

Hey guys,
Please help me…

Currently, i’m developing a Cocoa apps that view 3ds model with textures… I’m working it on 10.5 Mac… XCode 3.1.3
Everything is just nice… but this Mac only have Ati x1600
So is very slow when i load plenty of models…

So I try to open & debug it in 10.6 iMac using HD5750… Xcode 3.2
But all the textures have scanlines… and look terrible…

Anyone got this problem before…??

Please help…???

What do you mean by “scanlines” on textures?

The texture suppose to look like the “left”, which run on 10.5 Leopard…

Should I called it “scanline” or “artifact”???
plenty of this(red,green,blue) line on the texture…
You may right click and view image for bigger picture…

This is how I load texture:

texture_name[2] = [[NSBundle mainBundle] pathForResource: @"Plane2" ofType: @"jpg"];
object.objects_type[2].id_texture = LoadBitmap(texture_name[2]);

This is how I Read image/texture:

int LoadBitmap(NSString *filename) 
	NSBitmapImageRep *image = [NSBitmapImageRep imageRepWithContentsOfFile: filename];
	NSInteger samples = [image samplesPerPixel], 
	bitsPerPixel = [image bitsPerPixel], 
	bitsPerSample = [image bitsPerSample], 
	bytes = [image bytesPerRow];
	GLenum type, format = [image hasAlpha] ? GL_RGBA : GL_RGB;
	GLint internalformat;
	switch (samples) {
		case 4:
			if (bitsPerSample == 8) {
				internalformat = GL_RGBA8;
			else if (bitsPerSample == 16) {
				internalformat = GL_RGBA16;
			else {
				internalformat = GL_RGBA;

		case 3:
			if (bitsPerSample == 8) {
				internalformat = GL_RGB8;
			else if (bitsPerSample == 16) {
				internalformat = GL_RGB16;
			else {
				internalformat = GL_RGB;

			NSLog(@"GetOpenGLTexture: Can't handle samples per pixel of %d.", samples);
			return -1;

	switch (bitsPerPixel) {

		case 24:
		case 32:
		case 48:
		case 64:

		case 96:
		case 128:
			type = GL_UNSIGNED_INT;

			NSLog(@"GetOpenGLTexture: Can't handle bits per pixel of %d.", bitsPerPixel);
			return -1;

	NSSize size = NSMakeSize([image pixelsWide], [image pixelsHigh]);

	void *imageData = [image bitmapData];
	void *data = calloc(bytes, size.height);
	if( data != NULL ) { 
		int rowNum, Num = 0;
		for(rowNum = size.height - 1; rowNum >= 0;	rowNum--, Num++) { 
            // Copy the entire row in one shot
            memcpy( data + ( Num * bytes ),
				   imageData + ( rowNum * bytes ),
				   bytes );

	GLuint num_texture;
	glGenTextures(1, &num_texture);
    glBindTexture(GL_TEXTURE_2D, num_texture); // Bind the ID texture specified by the 2nd parameter

	// Set proper unpacking row length for bitmap
	glPixelStorei(GL_UNPACK_ROW_LENGTH, [image pixelsWide]);
	// Set memory alignment parameters for unpacking the bitmap 
	glPixelStorei (GL_UNPACK_ALIGNMENT, 1);
	// The next commands sets the texture parameters
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); // If the u,v coordinates overflow the range 0,1 the image is repeated
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // The magnification function ("linear" produces better results)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); //The minifying function
	glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE); // Create mipmaps automatically

    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); // We don't combine the color with the original surface color, use only the texture map.

    // Finally we define the 2d texture
	// And create 2d mipmaps for the minifying function
    glTexImage2D(GL_TEXTURE_2D, 0, internalformat, size.width, size.height, 0, format, type, data);

    free(data); // Free the memory we used to load the texture

    return num_texture; // Returns the current texture OpenGL ID

This is how I bind & use it:

glBindTexture(GL_TEXTURE_2D, object.objects_type[o_index].id_texture);

Anyone can spot the problem???

OK Guys…
Problem solve…

Nothing wrong with the codes…
The texture file format playing tricks…
Was using JPG format… So now using TIFF format solve everything…



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