VRayOSLTex and Dome Light problem

[illuMinator87]

Hi Chaosgroup,

I am trying to use the VRayOSLTex in "Vray3.00.02 Edu" in conjuction with the VRay Dome Light.
But when I try to use the global variables u and v in the OSL script, the rendering has errors on the dome light.



I narrowed it down to the very simple OSL script:

shader test
(
	output color result = 0
)
{
	result = color(v);
}

When I put the texture on a normal object, it works fine. It also works when I return a constant color.
So it looks like the u and v variables receive wrong values for the dome light.
Is there a way to fix this?

Best regards

[vlado]

You might have to use the viewing direction to compute the texture mapping; the dome light doesn't have u/v coordinates.

Best regards,
Vlado

[illuMinator87]

I'm not shure how to achieve the mapping with the viewing direction only. I tried to use P, but this results in kind of the same errors then with u/v (which probably makes sense, since the dome light does not have a defined distance from the origin??).
I guess I could achieve the mapping if I had the viewing position in addition to the viewing direction, but there is no variable in OSL for that.

[vlado]

You take the viewing direction, do inverse spherical mapping, and you get u/v values that you can use. If you need help with the inverse spherical mapping, let me know.

Best regards,
Vlado

[illuMinator87]

If you could give me some information about the inverse spherical mapping, that would be great! Thanks!

However, if I try to use the viewing direction (with the OSL global variable I) just as a simple output for testing, it renders completely black:

shader test
(
	output color result = 0
)
{
	result = color(I[0], I[1], I[2]);
}

I thought this should at least output some weird colors. When I put the same OSL script on an object, it seems to work.

Best regards,
Manuel

[vlado]

Yes, we found a limitation related to that (the dome light uses a different shade context); will fix it.

Best regards,
Vlado