Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: lupaz on 2019-11-10, 01:01:41

Title: Light material color affects the opacity when occlude is off?
Post by: lupaz on 2019-11-10, 01:01:41
Hi all,

Is this the correct behavior for "color" in Corona light material when "occlude other lights" is off?
I could swear that color was only affecting color and intensity, not opacity, in previous versions.

So, what you're seeing in this image is a gray color for "color". As you can see the sample turns transparent.
Title: Re: Light material color affects the opacity when occlude is off?
Post by: sprayer on 2019-11-10, 08:35:39
With corona light the same behavior, even more with occlude other lights off it lights brighter

(https://i.imgur.com/iJS2qSt.jpg)
Title: Re: Light material color affects the opacity when occlude is off?
Post by: lupaz on 2019-11-11, 15:55:07
With corona light the same behavior, even more with occlude other lights off it lights brighter


Not sure I understand. So is this a bug or normal behavior?
Title: Re: Light material color affects the opacity when occlude is off?
Post by: maru on 2019-11-12, 11:13:58
It's the same in V4 and V5.
I guess the explanation is that if something doesn't occlude light, then it has to let light pass through it = is transparent.
Title: Re: Light material color affects the opacity when occlude is off?
Post by: lupaz on 2019-11-12, 15:48:19
Thanks Maru.
I see a problem with this: Let's say I have a rectangle and I want it to emit more light in the center than on the sides with a gradient, but still be completely solid (no transparency). At the same time I don't want it to cast shadows.
It used to be easy with a gradient in color and turning "occlude" off. But now I can't.
Title: Re: Light material color affects the opacity when occlude is off?
Post by: maru on 2019-11-12, 17:07:43
It used to be easy with a gradient in color and turning "occlude" off. But now I can't.
What do you mean by "it used to be easy"? In which version? I just showed that it's the same in Corona 4 and 5.

In what exact situation do you need an object that emits light, is solid, and does not cast shadows?
Title: Re: Light material color affects the opacity when occlude is off?
Post by: lupaz on 2019-11-12, 17:33:13

What do you mean by "it used to be easy"? In which version? I just showed that it's the same in Corona 4 and 5.

In what exact situation do you need an object that emits light, is solid, and does not cast shadows?

Oh. I thought you meant that it behaves like this since V4, but not before.

In what situation? for example the shade of a lamp. I want it to emit light more on the center and less as it goes to the borders up and down, to mimic the effect of a light bulb being on the center.
At the same time I don't want that shade to cast shadows on the inside of the lamp, nor I'd like it to look transparent where it's not 100% white in color.