When you render the sequence, you should get a swimming pool light
reflection sort of effect without having to use radiosity, caustics, or
reflection, all of which occur in reality for a lighting situation like this
one. Your renders should be blistering fast too!
Using a LightWave Procedural Texture as a Clip
This isn’t exactly using projection images, but it functions sort of the
same way and it’s a cool little technique so we’ll discuss it here.
Simply take a single rectangular polygon and parent it to your spot
light. Scale and position it so that the polygon just covers the Light View.
Under the polygon’s Object Properties panel Render tab, click the Clip
Map Texture button.
Part II: LightWave’s Lighting Tools ······························
Here you can add any procedural texture you like, including animated
textures such as Underwater or textures with world coordinates so the
texture changes only as the light (and its projection polygon) move
through world space.
·······························Chapter 10: Projection Images