Hi everyone !
I’ve recently a implemented cascaded shadow map technique but I have some trouble with it when I enable PCF.
My implementation is really basic:
[ul][li]I set the view frustum so that the far plane is tighten to the scene.[]I compute my split based on a “magic” function []I render shadow maps into an array of depth texture[*]I determine the visibility of each pixel based on the shadow map. [/ul][/li]In order to avoid aliasing I add a small constant bias and a slope based bias. The slope based bias is computed using the technique presented here.
Apparently it works fine, as shown on the screenshot:
Full resolution image available here
When I enable PCF, shadows are OK but I get halos around objects, as shown on the screenshot:
Full resolution image available here
I suspect derivatives used for computing the slope based bias to be wrong. But I’m not sure. Does anyone of you as encounter such a trouble ?
Thank you in advance !
BTW, it’s implemented into a deferred pipeline.