ILM Lighting and Look Dev TD, Julius Ihle Shares His OSL WindowBox Shader Easily Creating Interiors That Will be Seen From the Outside of Buildings
One of the dilemmas in building and rendering a complete cityscape is how to handle what can be seen inside the buildings from the street-view. Do you build every room interior as geometry, or do you just have all the blinds and curtains drawn for each. There is another way that is pretty easy and saves on a ton of geometry and compositing. Map interiors with a box-like texture of a room. You can even take this a step further by mapping an entire room onto a single plane, and still have it look like it is a portal into an entire room, thanks to a WindowBox shader.
There is actually an easy way to do this, thanks to Julius Ihle. He has created a free-to-use OSL WindowBox shader that lets you easily map rooms onto simple geometry. Julius is a Lighting and Look Dev TD with Industrial Light and Magic who was drawn to how blockbuster films created such rich cityscapes. “I remember one of our teachers in university telling us about how they rendered all the interiors of the buildings in Spiderman with just a simple plane with a shader attached to it that simulates the room interior with proper parallax.” Julius says. “Since then this has always stuck in my mind and I saw it being used in some studios I worked at whenever there was a big city to be rendered. I finally found the time (.. too much time 🙂 ) to do this sort of shader myself in OSL!”
Julius’ WindowBox Shader can easily simulate the interior of a room on a single flat plane, having all the associated parallax as if it were a complete room. The shader is OSL (Open Shading Language) which means that it can be used with a variety of DCC’s and rendering engines that support the open shading language. “The package contains the source and compiled .osl and .oso files for Blender, Arnold and RenderMan, but it should work in any other renderer with OSL support.” Julius mentions.