How do I transform only one object in my scene or give each object its own transform?

Answer

OpenGL provides matrix stacks specifically for this purpose. In this case, use the ModelView matrix stack.

A typical OpenGL application first sets the matrix mode with a call to glMatrixMode(GL_MODELVIEW) and loads a viewing transform, perhaps with a call to gluLookAt().More information is available on gluLookAt().

Then the code renders each object in the scene with its own transformation by wrapping the rendering with calls to glPushMatrix() and glPopMatrix(). For example:

glPushMatrix(); glRotatef(90., 1., 0., 0.); gluCylinder(quad,1,1,2,36,12); glPopMatrix();

The above code renders a cylinder rotated 90 degrees around the X-axis. The ModelView matrix is restored to its previous value after the glPopMatrix() call. Similar call sequences can render subsequent objects in the scene.