Have been struggling all morning with this. If I have a dark scene, a simple plane, a sphere on that plane, an emissive object on one side of the sphere … then the sphere should cast a shadow on the plane, correct??? It works as expects with a point light, but if I use an emissive object the shadowing effect is lost. The sphere is lit by the emissive object correctly, but the plane is lit as though the sphere isn’t there … the light seems to pass
Maybe if you are using one of global illumination options it might give some light on other objects.
But generally emissive materials are just faking that the object is emmiting light.
And are not a real light source in realtime rendering.
You would have to place a light at the same location if you want it to emit light and cast shadows.
I haven’t used much of unitys more advanced lighting much so I could be wrong.
I am baking the lights, so I am not looking for real time, dynamic shadows, just baked ones on static objects. I think it should work, but can’t figure out where I am going wrong. I see it computing visibility, so it really shouldn’t light places it cannot “see” (like behind the sphere)???
Just to test this I made a similar scene. One set with light probes around an emissive texture set to 3.5, with a dynamic sphere object (static not set). Compared to no light probes, emissive texture but all objects set to static. There are no light sources in the scene or skycubes or similar. Conclusion: shadows can only be seen from an emissive source if the object is set to static, as described in the documentation.
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