In my July 14 article Kirsten Viewer S20 (29) Released I included a video by Marx Catteneo showing the use of Kirsten Dynamic Shadows and a Projector used like a flashlight. I think it is very neat effect.
Of course I wanted to know how it is done. So, how does one make a projector?
Well, it’s easy. One does have to be using the Kirsten Viewer S20 (24) and newer. (Opensource Obscure points out this works in SL 2.1 viewer too.) I made mine using S20 version (29).
You have to have Dynamic Shadows enabled, which means you also have to have Deferred Render active. See Kirsten Viewer Install Tips – That will help you get shadows working at a decent frame rate.
Set your shadows to Sun/Moon + Projectors. This will likely black your screen for a few seconds as it resets. It also pulled my frame rate down to 8 to 9 FPS from the 8 to 15 I was getting. But my projector worked.
Next rez a cube or cylinder. The projection will shine out the negative side of the Z-axis… the bottom of the cube or cylinder. (I have not tried other shapes. I assume any shape will work. A torus… well… may be not.) Select the Features tab of the build dialog. Check Light to make it a light.
Notice the 4 new fields on the dialog; a texture window, FOV (Field of View), Focus, and Ambiance. Without a texture the 3 numeric fields are inactive, they don’t do anything and there is no projection. It’s just a regular light.
Add a texture and the projector comes on and the light goes out. Any texture can be used. Black makes a dark area and white makes a bright area. Colored images project just like a RL slide projector. The FOV sizes the projection. It must be larger than 0.000 to see a projection. Focus works as you would expect. At zero it is very blurry and you will likely see some moiré patterns. Ambiance… well try it. It is hard to explain.
There are a couple of videos on YouTube.com that show what you can do with projectors.[youtube=http://www.youtube.com/watch?v=HpU7bB7ci2k] [youtube=http://www.youtube.com/watch?v=57JzSi-CyU0]