exclude terrains from light?

Nullcasting

Hey, Bryce forum!
I'm working on a render of a tropical reef, with half of the camera above the water and half below. I'm trying to set up a caustic effect using a distant light and gels, which works, except when i  exclude the 'ground item' group i made from the light, nothing seems to happen. Anyone know why that may be?

mermaid010

I don't think you can exclude or include groups. Someone with more experience will elaborate soon.

Horo

Apart from the sun, in all lights, including HDRI, you can exclude objects to receive light - but NOT groups. Ungroup the group that must not receive the light and exclude all elements separately. I hope this will work for your scene.

Nullcasting

Thank you Horo and Mermaid! I'll try that now. :V)

Edit: I'm unable to see terrains in the exclude/include menu.  is there something special I have to do?

ok big edit. I think the issue is that my terrains are in groups, but i have them in groups to apply boolean operations to them (the positive/negative stuff). going to try ungrouping some unecessary groups to reduce the amount of options in my drop down menu in case that's part of the problem but i think that the groups themselves may be the issue. i think i may try exporting the models into maya and make the boolean operations permament

Horo

Too bad. I understand why you must group the terrains. You can also try to export the terrain group directly in Bryce as either 3DS or OBJ and then replace your group by importing the exported one. I am not sure, but I think OBJ are smoothed and 3DS are not.

Electro-Elvis

First I thought you could simply ungroup your terrains, exclude the specific terrain and at the end regroup them again, but after a quick test I realized, this approach does not work. The grouping overrules the exclude option.

The only thing you could do in Bryce is the opposite way: you include all other objects, except for the grouped terrains. I know that unfortunately this can be quite a chore when you have a large amount of objects.

S Ray

Try this. Select the group & turn it to a mesh by clicking the C on it's attribute selection. Then select the light & go to the light lab. The terrains will still show as a group on the include/exclude list, but Bryce will now see it as a mesh, even though it still appears on the group menu.  Here I did a quick test turning off the sunlight & used a radial light with green color to make it easy to tell this works.
 

S Ray

Here's the same set-up with the sunlight turned on.
 

NGartplay

Thanks S Ray