I’ve noticed a strange shadow bug in the Path Tracer when a material has refraction turned on.
It’s only visible when the surface is indoors or in shadow.
This light comes from the “shadow” of the sphere. The sphere is in an enclosed room with a ceiling blocking the sunlight, yet the light still passes through when the shadowrays pass through the refractive sphere.
Though it may not look it, the sphere has refraction turned on, but it’s subdued.
Base color also has alpha set to 50%.
Inverted shadow follows the sun since the sun is the only light source in this scene.
Still visible when base color alpha is set to 0%, but transmission color set to 15% black.
This inverted shadow bug is odd to say the least.