Lights are very inefficient in webgl / V3D. Each light causes the number of redraws and triangle count to increase to the point where its not sustainable.
If you need 8 lights in your scene it would be better to create an environment map with the 8 lights in the HDR and then if you need light cones or to be able to see your lights in the environment you can create objects that have emission or a gradient texture for a light cone that fakes the light glare…etc.
I always recommend you look at your scene stats in Blender and watch the triangle count then when you get to V3D view how many triangles you have….for each light you will see the number multiply along with redraws…this is what you have to avoid.
So use lights sparingly and better yet…avoid using them completely if possible.
You can test what I am saying by creating a simple cube scene with no lights. Save it and record the performance properties…..then add a light do the same thing…add another light and do it again…and you will see how quickly that simple cube becomes a problem…not because its a cube…but because of the lights.
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