Thread: Photo Maps
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Old March 21st, 2008   #7 (permalink)
crazy homeless guy
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Name: travis schmiesing


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Default Re: Photo Maps

Quote:
Originally Posted by 3dsmax tutorial files
It works with any light, no matter how "unphysical,” since it is concerned only with the transport of light from surface to surface, not the transport of light from the light to the surface.
So. What I am making out is that the photon map is a map of the light, or more precisely the transport of the light. This is why changing the geometry does not affect the map. The photon map already has the amount of light that will strike a newly introduced surface or geometry modification stored into the file. However, if I add additional, or change the light source, I will need to re-compute the photon map because the map of the light is no longer accurate to the actual lights in the scene?

Whereas, or at least I believe that, irradiance maps pretty much become invalid as soon as the geometry is changed. I say this because if you open the Vray irradiance map file in the irradiance map viewer, you can see that that the surfaces are defined by how the light hits them. If you move a surface, the saved irradiance map does not reflect that move without recalculating. Or at least it does not reflect it with any deal of accuracy.

Is there a viewer, or any way to look at a photon map to better understand how it works?

…also, I assume that placing geometry close to a light source will affect how the photon map should behave, therefore making the saved map un-accurate because the distribution of light in the scene would have changed(?).
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