Thread: OpenGL texture mapping with texCoordArray

So I'm trying to work out how texture mapping with a texture coordinate array works, but whatever I seem to do I only get a white quad instead of a textured quad.

This is a modified texture mapping example I found on the net, but using vertex and texCoord pointers instead of glTexCoord2f and glVertex3f and whatnot.

Anyway, here's the relevent sections of the code:

variables:

Code:

double vertexArray[] = { -0.75, -0.75, -6,
					 0.75, -0.75, -6,
					 0.75,  0.75, -6,
					-0.75,  0.75, -6 };
								
double colorArray[] = { 1.0, 0.0, 0.0,
				      0.0, 1.0, 0.0,
				      0.0, 0.0, 1.0,
				      1.0, 1.0, 0.0 };
					    
double texCoordArray[] = { 0.0, 0.0,
					    1.0, 0.0, 
					    1.0, 1.0,
					    0.0, 1.0 };

(somewhat messy) Code that is suppose to render the quad.

Code:

void DrawAQuad() {
 glEnableClientState(GL_VERTEX_ARRAY);
 //glEnableClientState(GL_COLOR_ARRAY);
 glEnableClientState(GL_TEXTURE_COORD_ARRAY);
 
 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

 glMatrixMode(GL_PROJECTION);
 glLoadIdentity();
 glOrtho(-1., 1., -1., 1., 1., 20.);

 glMatrixMode(GL_MODELVIEW);
 glLoadIdentity();
 gluLookAt(0., 0., 10., 0., 0., 0., 0., 1., 0.);

 glClientActiveTexture(textureID);

 glVertexPointer(3, GL_DOUBLE, 0, vertexArray);
 //glColorPointer(3, GL_DOUBLE, 0, colorArray);
 glTexCoordPointer(2, GL_DOUBLE, 0, texCoordArray);
 
 glDrawArrays(GL_QUADS, 0, 4);
 
 glDisableClientState(GL_VERTEX_ARRAY);
 //glDisableClientState(GL_COLOR_ARRAY);
 glDisableClientState(GL_TEXTURE_COORD_ARRAY);
}

Code used to upload the texture data:

Code:

glGenTextures(1, &textureID);
glBindTexture(GL_TEXTURE_2D, textureID);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

glTexImage2D(GL_TEXTURE_2D, 0, bytesperpixel, width, height, 0, bytesperpixel, GL_UNSIGNED_BYTE, imageData);

imageData is an array with unsigned char's containing data for a 256x256 map loaded from a uncompressed, unmapped TGA, basically just an ordinary bitmap.

So, the big question, what am I doing wrong? As stated, all I get is a white quad.

I apparently some way along the way made the assumption that GL_RGB mapped to '3', which it obviously didn't, so instead of the 'bytesperpixel', I just had to use GL_RGB instead.

Must take note about checking for returned error codes in the future.