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weird color problem

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hi, The problem is that when I load a texture, other colors that I want to use get messed up. They turn into different colors when I load different textures. I managed to reproduce this problem by taking Nehe's lesson6 (the first texture loading lesson) and merge DrawGLScene() function with the one in lesson3. You will see that the cube in front is drawn like it should( with texture on it), but the triangle and quad(from lesson03) in the back will not have the color they should have. I have no idea why that is and its driving me nuts! Anybody got an idea what's wrong here? Here's the code of the new DrawGLScene() function.
int DrawGLScene(GLvoid)
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glLoadIdentity();
	glTranslatef(0.0f,0.0f,-5.0f);

	glRotatef(xrot,1.0f,0.0f,0.0f);
	glRotatef(yrot,0.0f,1.0f,0.0f);
	glRotatef(zrot,0.0f,0.0f,1.0f);

	glBindTexture(GL_TEXTURE_2D, texture[0]);

	glBegin(GL_QUADS);
		// Front Face
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
		// Back Face
		glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
		// Top Face
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
		// Bottom Face
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
		// Right face
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
		// Left Face
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
	glEnd();

	xrot+=0.3f;
	yrot+=0.2f;
	zrot+=0.4f;


	glLoadIdentity();
	glTranslatef(-1.5f,0.0f,-6.0f);
	glBegin(GL_TRIANGLES);
		glColor3f(1.0f,0.0f,0.0f);
		glVertex3f( 0.0f, 1.0f, 0.0f);
		glColor3f(0.0f,1.0f,0.0f);
		glVertex3f(-1.0f,-1.0f, 0.0f);
		glColor3f(0.0f,0.0f,1.0f);
		glVertex3f( 1.0f,-1.0f, 0.0f);
	glEnd();
	glTranslatef(3.0f,0.0f,0.0f);
	glColor3f(0.5f,0.5f,1.0f);
	glBegin(GL_QUADS);
		glVertex3f(-1.0f, 1.0f, 0.0f);
		glVertex3f( 1.0f, 1.0f, 0.0f);
		glVertex3f( 1.0f,-1.0f, 0.0f);
		glVertex3f(-1.0f,-1.0f, 0.0f);
	glEnd();


	return TRUE;
}

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Because opengl is a state machine, once you declared a texture, everything draw nafter that will have that texture no matter what. There are two ways to not use a texture.

glDisable(GL_TEXTURE_2D);

right before you draw the items that wont have a texture

But you might want to turn it back on later if you decided to draw a texture item

so glEnable(GL_TEXTURE_2D);

you can also use:

glBindTexture (GL_TEXTURE_2D, NULL);

but I recommend using gldisable.

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