PBR update

Entry posted by Mattline1 · May 1, 2017

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I first presented my PBR work about a year ago, since then I've been tweaking and making improvements.

Over the past 6 months Leadwerks has had some great updates for graphics junkies like me .The HDRi and environment probe features look great and have helped with 2 of the main issues with the last PBR system. Now what you see in the editor is what you get in the game, and HDR means proper tonemapping and a wider range of possible light intensities. Both of which are important for realistic PBR.

I currently plan on using this for my current project, so expect consistent updates as I battle test it.

The current build is available on github. Any issues and suggestions to help improve it are welcome.

The project is available from GitHub

Limitations / improvements

Requires a gamma-correction post process shader. Not a huge issue, adding a pp is pretty easy but still something to remember.
Currently the built in environment probes are stored in a low dynamic range. This leads to clamping and precision errors as HDR values move towards extremes. this limits the usefulness of HDR. This is an engine issue.
Probes also use simple mipmapping for different roughness values, PBR often performs a convolution on stored cube-maps to better match reflection blurring due to roughness. A fix may be possible for this, but would require C++.