Plant Shader

One of my final projects was to create a "shader" in Renderman for a plant.  The idea of a shader is essentially all the colors and patterns of a surface as well as the way the light interacts with it.  In short, it is a tool that the user adjusts that makes 3D objects look like what they represent.  So a rock will have a rock shader, a tree with a tree shader, and so on.  But in reality, these shaders are rarely so specific.  Most shaders are adjustable to look like a variety of things, and you can stack things on top of each other to change the look.  It gets really involved actually.  But to actually write a shader out by hand means you have far more freedom to make something look exactly like what you want, and for a very specific purpose.  As such, we were learning how to make an organic plant shader.  We actually had to go out and buy plants to study the patterns and figure out how to recreate the look with a coded shader.

I admit my shader is not as refined as I would like it to be.  I intend to take it further and add what are called "octaves", which is really just another level or two of detail, to really refine the shader.  I also want to refine the controls, but overall I am pleased with what I was able to come up with.  I would love to learn how to implement things like image based lighting and ambient occlusion into the shader, so I may have to study this on my own.  There is so much more to learn for shader writing, and I really enjoyed it so I wouldn't mind diving into this more.

So for now, here is a final render of my shader.  All aspects of it (including the interaction of light and shadow, the transmission of light, the backside colors, and so much more) are developed by me, and I hope to take it further.

Enjoy!