[Link] Physically Based Rendering

Collecting links for Physically Based Rendering

PBRT
http://www.pbrt.org/index.php

Mituba - Physically Based Renderer
http://www.mitsuba-renderer.org/

Octane Render
http://render.otoy.com/

DONTNOD specular chart
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http://seblagarde.wordpress.com/2012/04/30/dontnod-specular-and-glossiness-chart/

http://seblagarde.wordpress.com/2014/04/14/dontnod-physically-based-rendering-chart-for-unreal-engine-4/