Def hit_test (x, y) : 
Buffer_size=512 
Viewport=glGetIntegerv (GL_VIEWPORT) 
Aspect_rat=(viewport [2] - viewport [0])/(viewport [3] - viewport [1]) 
GlSelectBuffer (buffer_size) 
GlRenderMode (GL_SELECT) 
GlInitNames () 
GlPushName (0) 
GlMatrixMode (GL_PROJECTION) 
GlPushMatrix () 
GlLoadIdentity () 
GluPickMatrix (x, viewport [3] - y, 5, 5, viewport) 
#... The Draw Something using glLoadName... 
GlPopMatrix () 
GlMatrixMode (GL_MODELVIEW) 
GlFlush () 
Buf=list (glRenderMode (GL_RENDER)) 
Print (buf) 

This is a code, the great god, please have a look at how to change