View Full Version : photon energy loss based on hit count

04 April 2006, 07:47 AM
is there a way to control (increase/decrease) the energy of a photon after it hits a surface? for example tell a photon to lose 50% of energy after 1 hit, 25% more after a 2nd hit and so on.

raising the exponent does not do the trick even at really high amount and high photon intensity, although there is a difference(it does decay more), it is a minimal effect and i want a much stronger decay effect not based on distance function! but hit counts.

04 April 2006, 12:42 PM
well you have the photon shader to do that.
you ctrl its properties there and the photons
will change their behaviour. for example a
black opaque mat is not reflecting photons
as a white specular one. it is a physical
behaviour and you naturally tweak the mats
to change the way the light reacts to them.
then there're global params like exponents
and n. of max bounces and global photon


04 April 2006, 04:43 AM
well the problem there is it still doesnt allow me to have a lot of energy bounce after the first hit and almost complete energy loss by the 2nd or 3rd hit. even when i use the photon basic shader the photon energy spread is still very equal all around the scene and to as many hits that i have set(2 bounce right now).

isnt there a way to color the photon based on how many surfaces it hit so far?

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04 April 2006, 04:43 AM
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