Blender Cycles Shadow/Splash Board

Blender Cycles Shadow/Splash Board

Hey guys. so for my most recent project I’ve been working with compositing inside the Blender Cycles engine. Up until fairly recently it wasn’t possible to create a shadow board within Cycles alone, instead requiring awkward and complex work around using both the new and old engines to fake the effect. In fact one of my first posts to this blog was to demonstrate this using both shadow boards and sub-surface scattering. Thankfully a shadow input (among others) has finally been added allowing us to finally create a composite scene entirely using the Cycles engine.

The setup above shows how this is executed. By placing your objects and your environment into separate render layers you can mask each from the other in the scene panel. This means when rendering the ground, the foreground object appears black. Vice versa for the object layer. When inside the compositor you can render out  separate channels of ambient occlusion, shadow and indirect diffuse from the environment layer. This is important as it gives you control over the look and intensity of each parameter to match the scene you’re compositing into. These parameters can be seen individually in the bottom left of the second image. The indirect diffuse layer must be added back into the mix after the video plate is introduced to add bounce light back onto the floor. This is especially important for glossy or brightly coloured objects which reflect light. That pretty much sums up what is needed, after all this time it is fairly quick to achieve a reasonable looking composite using the compositor almost exclusively.

The only thing I haven’t mentioned is the reflection on the cube which I achieved using a quick and dirty 2.5D projection to the floor, which is necessary for reflective objects. I’ll be posting a follow up to this soon describing how to achieve a complex composite where masks, holdout objects and lights are introduced which is a whole different story. Until then I hope you enjoy!