hemi light shadows

why does using raytraced shadows with hemi lights give weird artifacts?

just turn the lamp in the default scene in blender into a hemi and turn on raytraced shadows, it gives weird artifacts on the cube.

or are hemi lights not supposed used with shadows? But then why do we have a ray shadow option for it?

just wondering…

Just turn off Shadow in the rendering options, then it works fine.

HAHAHAHAAAAhahaa owww my sides! HAHA

Sorry :smiley:

I think you would be better off avoiding shadows on hemi lamps

the hemi lamp type (iirc) is light coming from a half sphere (hemisphere) towards the center of the lamp, kind of. it lights like a bunch of sun lamps pointing every direction, except combinations of down (the direction the hemi lamp points)

raytraced shadows were an attempt to add shadows to ALL lamp types, it is most useful for regular (point, omnidirectional) lamps and sun lamps

well anyway, the artifacts you speak of may be related to the fact that the direction of the hemi lamp (it points towards the center of the hemisphere of where the figurative infinite number of sun lamps point) is pointing along (remember, sun lamps, and hemis don’t have perspective) the side of the cube, the artifacts are a math error. if you rotate the lamp just a smidgen (0.01) the errors disappear

Due to all of this, shadows for the hemi lamp have been removed in the latest CVS. The effect of a hemi-cast shadow can be acheived with the AO settings in the World buttons.


That’s what everyone whose avatar is an O says.