   Volumetric Shadows...part 2
  ok, just following up on my Volumetric Shadows post yesterday.  I believe I know what the problem is, opengl rendering adjacent polygons.  E.g.The two triangles (a shadow volume)glBegin(GL_QUAD_STRIP);glVertex3f(0, 0.1, 0);glVertex3f(0, -100, 0);glVertex3f(0, 0.1, 2);glVertex3f(0, -100, 2);glVertex3f(2, 0.1, 2);glVertex3f(2, -100, 2);glVertex3f(0, 0.1, 0);glVertex3f(0, -100, 0);glEnd();glBegin(GL_QUAD_STRIP);glVertex3f(0, 0.1, 0);glVertex3f(0, -100, 0);glVertex3f(2, 0.1, 2);glVertex3f(2, -100, 2);glVertex3f(2, 0.1, 0);glVertex3f(2, -100, 0);glVertex3f(0, 0.1, 0);glVertex3f(0, -100, 0);glEnd();are rendered into the stencil buffer.  When the scene is re-rendered to update the pixels in the shadow volume, pixels from the texture underneath are popping though the adjacent edge (0,0) to (2,2) of the shadow.  I dont think this is z-fighting, more like the pixels drawn to the stencil buffer (when the vertices of the polygon are projected out from the light) are snapping to the wrong pixel.So...anyone else had problems with opengl drawing adjacent triangles, and if so, how can I get round it!thnxLloyd  