I just started with this. Calculating the 3D Locations of 640*480 Pixels of a rendered image took only 240 Millisecs, while 640*480 camerapicks took 108'782 Millisecs.
The Algorithm isn't pefect or very flexible by now, but it kinda works, the calculated position is about the same as the one returned by Camerapick. I guess some 3D Gurus will easily optimize this step of 3D Calculation.
That is nice, tho now I still got to find a way to check for visibility of the light, or of the lumel seen by the light.
Probably the easiest way will be to render the 6 sides of a cubemap seen from the lights position and then calculate on what side a 3D Location (they are nicely stored in arrays btw.) should be, and where exactly it should be. As I described before it should then be possible to determine the visibility of the lumel by the brightness of the pixel.
Not a single Linepick would be used that way, but unfortunately there are 7 additional Renderworlds, plus a lot of readpixel and writepixel.
The Algorithm isn't pefect or very flexible by now, but it kinda works, the calculated position is about the same as the one returned by Camerapick. I guess some 3D Gurus will easily optimize this step of 3D Calculation.
That is nice, tho now I still got to find a way to check for visibility of the light, or of the lumel seen by the light.
Probably the easiest way will be to render the 6 sides of a cubemap seen from the lights position and then calculate on what side a 3D Location (they are nicely stored in arrays btw.) should be, and where exactly it should be. As I described before it should then be possible to determine the visibility of the lumel by the brightness of the pixel.
Not a single Linepick would be used that way, but unfortunately there are 7 additional Renderworlds, plus a lot of readpixel and writepixel.