Rendering Notes

Transparency

Crest is rendered in a typical way for water shaders: in the transparent pass and refracts the scene. The refraction is implemented by sampling the camera’s colour texture which has opaque surfaces only. It writes to the depth buffer during rendering to ensure overlapping waves are sorted correctly to the camera. The rendering of other transparent objects depends on the case, see headings below. Knowledge of render pipeline features, rendering order and shaders is required to solving incompatibilities.

Transparent Object In Front Of Water Surface

Normal transparent shaders should blend correctly in front of the water surface. However this will not work correctly for refractive objects. Crest will not be available in the camera’s colour texture when other refractive objects sample from it, as the camera colour texture will only contain opaque surfaces. The end result is Crest not being visible behind the refractive object.

Transparent Object Behind The Water Surface

Alpha blend and refractive shaders will not render behind the water surface. Other transparent objects will not be part of the camera’s colour texture when Crest samples from it. The end result is transparent objects not being visible behind Crest.

On the other hand, alpha test / alpha cutout shaders are effectively opaque from a rendering point of view and may be usable in some scenarios.

Transparent Object Underwater

This is tricky because the underwater effect uses the opaque scene depths in order to render the water fog, which will not include transparents.

Rendering the transparent object after the underwater pass (occurs right after the transparent pass) with reduced transparency can often be good enough.