Following image was rendered via pathtracing. It contains just a single HDRI light and simple geometries with Principled materials:
If we add a geometry light (small sphere with Luminous material), the overall brightness is significantly reduced:
We found out that this issue was introduced with commit cbf9d26. So it can't be reproduced with OSPRay 2.7.1 and earlier. A possible fix is to change computation of selectionPDF in VirtualLight.ispc from:
Following image was rendered via pathtracing. It contains just a single HDRI light and simple geometries with Principled materials:
If we add a geometry light (small sphere with Luminous material), the overall brightness is significantly reduced:
We found out that this issue was introduced with commit cbf9d26. So it can't be reproduced with OSPRay 2.7.1 and earlier. A possible fix is to change computation of
selectionPDFin VirtualLight.ispc from:const uniform float selectionPDF = rcp((uniform float)pathContext.numLights - w->pathtracerData.numGeoLights);to:
const uniform float selectionPDF = rcp((uniform float)pathContext.numLights);But currently I'm not sure if this change has unexpected side effects.