OpenGLContext.scenegraph.polygonsort

Polygon sorting support functions for ArrayGeometry

For your transparent geometry, get a set of object-space centers for the triangles being drawn: centers( self.verticies )

Store this somewhere, as you'll need it on every transparent rendering pass. During the pass, when you get to the point where you want to draw the transparent geometry: map( gluProject, centers centers[:,1 , centers [modelview *len(centers), [viewport *len(centers), )

Then take the z values from that and pass to: indices( zFloats )

glDrawElements( GL_QUADS, GL_UNSIGNED_INT, # this changed with PyOpenGLSWIG 2.0, not previously needed indices )

Functions

distances( points , modelView = None , projection = None , viewport = None , astype = 'f' )

Get eye-space Z coordinates for given centers

Does less work than a full project operation, as it doesn't need to calculate the x/y values.

indices( zFloats )

Calculate rendering indices from center-distance-floats

zFloats: distance-to-center-of-polygons as calculated by the distances function

calculates indices required to render from back to front (least float to greatest float)

project( points , modelView = None , projection = None , viewport = None , astype = 'f' )

Do the equivalent of a gluProject on all points (transform to eye coords)