demostenes Posted November 18, 2012 Posted November 18, 2012 I ve noticed, that shadows tend to disappear, when I just rotate camera. I am staying in forest (so there is lots of shadows from various trees), no change of position, but when just looking more down or rotate. Shadows are corrent only in case I am facing sun directly +-45 degrees. If I rotate more, lots of them disappears. Bigger rotation, less shadows. When I am backwards to the sun, almost all shadows are gone. Am I doing something wrong? Bug?
frustum Posted November 19, 2012 Posted November 19, 2012 Please try to increase the shadow radius of object mesh cluster/clutter objects.
demostenes Posted November 19, 2012 Author Posted November 19, 2012 Yes, thanks increasing shadow radius helped. Anyway to cover scene in the evening with very low sun (long shadows) means to have it at least 100 for each tree mesh clutter and performance drop is very significant. Why is this happening? I would expect, that just rotating without moving will not turn off some shadows (facing sun +-45 degrees makes visible all of them).
frustum Posted November 19, 2012 Posted November 19, 2012 Clutter performs view frustum culling of objects. So only visible objects cast shadow. Shadow radius parameter helps to remove shadow artifacts by increasing the visible view frustum size. Long shadows require big shadow radius. You can change the shadow radius dinamically with respect to sun angle.
demostenes Posted November 19, 2012 Author Posted November 19, 2012 Clutter performs view frustum culling of objects. So only visible objects cast shadow. Shadow radius parameter helps to remove shadow artifacts by increasing the visible view frustum size. Long shadows require big shadow radius. You can change the shadow radius dinamically with respect to sun angle. Thanks for explanation! Is it possible to make objects which are not in the frustum shadow casters?
ulf.schroeter Posted November 20, 2012 Posted November 20, 2012 That's exactly what the shadow radius of world light does: even if an object is not within view frustum (e.g. Behind viewer), but within shadow radius, then it will cast shadows
demostenes Posted November 20, 2012 Author Posted November 20, 2012 That's exactly what the shadow radius of world light does: even if an object is not within view frustum (e.g. Behind viewer), but within shadow radius, then it will cast shadows Ah ok. So object is not rendered, only shadow. Btw, it is possible to somehow control rendering of shadows? For example I dont need update of shadow each frame, so do it only each 3rd frame, or even specify frequency of update shadow per object (shadow of building will move very slow according to sun, so there is no reason to make updates each frame...)? Did anybody try to make lightmap with more frames (20-30) and use it for faking dynamic shadows of stationary objects cast by sun?
manguste Posted November 27, 2012 Posted November 27, 2012 I'm afraid specifying frequency of update shadow per object is not possible. Moreover, it's not so good idea as may seem. 1. Keeping resources from the previous frame is not performance friendly from a graphics card point of view. 2. Shadowing artefacts are imminent. 3. Composing the final shadow map with objects updated at different rates is a problem.
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