VraySun - Sharp Shadows

V-Ray V-Ray for 3ds Max Requests
1

Howdy,

Would it be possible to have a option within the VraySun settings to disable area shadows. The VraySun is a great way of generating a realistic daylight effect, however area shadows really slow it down.

In some instances the renders are taking 20 times longer than if I used a standard direct light with VrayShadows.

The great advantage of the VraySun light object is its physically correct for colour and intensity, i’d hate to have to stop using it because rendertimes are to expensive.

Drew Wood-Davies
Bruce Henderson Architects

2

Reduce the sun size to something very small, and you have sharper shadows.
How small depends on scene scale.

Lele

3

Yeah i can do that, but it would really like the option of turning off area shadows all together.

4

maybe a “convert vray sun to directlight” script would be nice

5

You could align and link a direct sun to the vray sun, turn off the vray sun, and then wire the direct light’s intensity and color parametersto the vray sun.

It’s kludgy, but it should work.

6

Dynedain,

That would be a great solution, however the colour and intensity values need to translate somehow. The multiplyer for the VraySun at 1.0 is much higher than a Direct Light at 1.0.

Also, the colour value for the light seems to be determined by the sun angle, I can’t think of anyway to access this for wiring.

Drew

7

Put something very small as the sun size AND set the subdivs to 1. This will get you very close to a direct light quality- and speed-wise.

Best regards,
Vlado

8

plus u ll get a more physical light distribution and color.
:wink:

9

It seems simple, but it isn’t.
Unless the light intensity (and colour)of the sun decreases linearly across the angle, which i very much doubt, it’s some really challenging scripting to be done.

Much better to go Vlado’s way, says i…

Lele

10

thanks guys,

I will give it a try and post my results.

Drew