Raytraced / Cycles lighting questions

Hi Nathan,
I just noticed that the latest wip update had my reflected light turned off:

So I had to reset it to 2 (I presume that was the default) for it to render properly again.

Oh, and PS! This is what the OpenGL Rendered mode looks like :expressionless:

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And two wishes for Point lights:

1: Size
2: Fall off

The size of a point light is important for achieving softer shadows.
(It’s an old feature and even Flamingo 1.1 supported that is important for realistic images)
See how the shadow is equally sharp regardless of distance to point light:

This is the same scene with the light turned off, just to illustrate that the lighting is almost entirely from the pointlight.

And another thing, here the scene is with the light at 3 % and see how the background is all light gray, for some reason the environment/ground isn’t reacting properly to the light intensity.


And one more thing before I go:
Emissive materials are not advanced enough.
1 - First of all they are not emitting light as they used to.
2 - We need to set the emissive strength with a slider and a value so we can go beyond 100%. setting it with color isn’t good enought as we might need a spesific RGB value and thus manually calculating say 11% of that RGB value isn’t going to happen.
3 - We need to be able to set an emissive material/image

Here a picture plane is shown next to a plane with a material where I sat emission to close to 50% gray. And that turns even the black parts of the image gray. It can work if I want to illustrate an old, worn projector image, but not ok if I want it to look like a modern OLED UHD TV :wink:

Thanks for listening!

The current default is 0 to be closer to Rhino Render. Indeed 2 (or higher) for more realistic rendering.

Rhino lights aren’t going to see any changes for 6.x. None of the Rhino lights have fall-off (which is a PITA). That said: instead of using point lights you could add spheres (or any form object really), then add Cycles emissive material.

edit: note that with Fall-off you also need to have a separate strength control. 0-100% doesn’t mean anything, but rather you’d need a way to input the energy strength (which you can with Cycles emissive material).

SphereLightWithCyclesEmissive.3dm (197.9 KB)

If you can’t see the emissive material run TestShowPrivateContent.

This way you can create essentially neon tube figures.


Can you attach a file that shows this? Then I don’t have to guess all the settings (:

The Rhino Custom material with emission is indeed very limited. The best way to get a bright image is to use self-illumination. This causes materials to show up bright even when in shadow. Unfortunately for Rhino Custom self-illumination the shader has been set up to not have such objects cast light.

I’m creating some YT items for tracking requests. I have created the following YT items: RH-42038, RH-42039 and RH-42040

Thanks for the reply!
I’ll test some more later, now I am at the office where I don’t have a file to send.

(This is not to critizise you Nathan, but rather to let you know how we feel: )
Please, PLEASE do not let Rhino render dictate what Cycles can or can’t do. Cycles need to be as good as it can be from day one and then evolve from there. It has to surpass Neon as 5 years has passed and if Rhino render doesn’t have reflective light then that is Rhino renders problem. Rhino render should evolve instead of limiting new technology. So Please bring back reflective light as default. I know of no other rendering package or design tool that does not support reflected light these days, and it is crucial for a realistic and tasty image.

I understand your concern. The problem here is that with the default setup Rhino offers simple scenes become way too overlit (for which I then again get bug reports). This also doesn’t give a good impression. We’re still trying to find a good balance for default setup.

Yeah, I understad the logic there too, but Rhino render was allowed to limit the OpenGL ability when Rhino 5 was developed and I hate to see that happen again now ten years later too. All due to a renderer that is far below par. (It might be harsh, but I don’t think I am exaggerating, at least I try not to)

I vote that you guys ship Rhino with Cycles as default, and keep Rhino Render as a backup/backward capability feature.

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I do completely understand where you come from. I have restarted the discussion regarding this. Rest assured we want the best stuff in v6.