11.2.1.2 Using a Sphere Map

To use sphere mapping in OpenGL, the following steps are performed:

28.

Bind the texture containing the sphere map.

29.

Set sphere mapping texture coordinate generation:

glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);
glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);

30.

Enable texture coordinate generation and 2D texturing:

glEnable(GL_TEXTURE_GEN_S);
glEnable(GL_TEXTURE_GEN_T);
glEnable(GL_TEXTURE_2D);

31.

Draw the object, providing correct normals on a per-face or per-vertex basis.