Timeline for How to simulate specular reflection in Light Tracing?
Current License: CC BY-SA 3.0
7 events
when toggle format | what | by | license | comment | |
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Sep 11, 2017 at 6:30 | comment | added | Stefan Werner | This will only work if your camera is not a pinhole but simulates a non-zero sized aperture and a film. Then you can continue the reflect light path through the aperture and record it once it hits the film plane. | |
Sep 9, 2017 at 3:42 | comment | added | Alan Wolfe | Darn, hrm. Maybe the problem is you can't have pure mirror specular reflection, but need a specular lobe that isn't a delta function spike. | |
Sep 9, 2017 at 1:43 | comment | added | ali | Thanks but I guess it's impossible to simulate this sort of path in forward ray tracing; since an incoming ray from light to a specular surface point it has zero probability of going out towards the camera as it has a delta function. | |
Sep 9, 2017 at 0:36 | comment | added | Alan Wolfe | Have you considered using fresnel to figure out how much light is reflected vs transmitted, then using that value as a percent chance to do diffuse or specular lighting? If specular, since you are asking about mirror like specular only, you just reflect the vector against the surface normal. If that is making sense, if wanting to go beyond mirror like specular reflection, you could use eg a microfacet specular BRDF instead later. | |
Sep 9, 2017 at 0:28 | comment | added | ali | Yes it is forward ray tracing as opposed to backward ray tracing. It traces importance, rather than radiance, from the light source, bouncing it around the scene and connecting each vertex to camera. | |
Sep 9, 2017 at 0:24 | comment | added | Alan Wolfe | I hadn't heard the term light tracing before. For other folks who haven't either, it seems to just be path tracing from the light towards the screen, vs the normal screen towards light. Similar to photon mapping, but without the photon? | |
Sep 8, 2017 at 21:11 | history | asked | ali | CC BY-SA 3.0 |