Uh....

Support Basics & Interface
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Okay, I have a few bits of understanding I would like to share with you:(Not to be patronizing, or course :wink: )
Okay, now everyone here, and all of the blender developers seem to think radiosity is acheived becase all objects emit light.

This is wrong.

If all objects emitted light, then even in the darkest place, you would be able to see every object, in crystal clear clarity.

But you can’t.

So, how radiosity works, to the best of my understanding, is that all objects REFLECT light, but most surfaces are diffuse(bumpy) enough, so that they only reflect colors, and only a short distance away. Mirrors and glass, on the other hand, are not diffuse, and so they reflect light clearly, and very far away.

Anyway, the reason I decided to post this, is that in the “distributed raytracing” thread, one person posted that "Diffuse refelctions would be a great way to fake radiosity. But since diffuse reflections are how radiosity actually works, it would actually be realistically simulating radiosity, and the current method would be the “faking” method.

Anyway, I’m sure some(or most) of you already know this, but I decided It needed to be said. :slight_smile:

Edit: also, every shader imaginable could be created with just 3 variables:

Color, bumpiness, and transparency

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Okay, now everyone here, and all of the blender developers seem to think radiosity is acheived becase all objects emit light.

Eeeeeeh… this light thing is very basic…how can…you say all the community including the genius coder think like this? :stuck_out_tongue: :wink:

Yes, light did bounce :smiley:

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Radiosity is calculated in a similar way to how it works. Light is emitted from objects, then absorbed by others. This is re-emitted and sent on its merry way, etc, etc.

The order this is done in the radiosity calculations is not correct, but leads to a good image.

If all objects emitted light, then even in the darkest place, you would be able to see every object, in crystal clear clarity.

All objects emit light. Just in dark places, they dont emit light very much as they dont recieve much. To emit light, an electron needs energy, this usually comes in the form of light. Light gets absorbed then re-emitted.
Shaders can change colour from the angle they are viewed at. Also relfection and refraction need other parameters.

Ian

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Disclaimer: I really don’t have any idea or knowledge on how this stuff works :expressionless:

However, there are some raytracers, like Radiance, that are aimed at calculating correct (not just convincing) lighting in a scene. I think Radiance was developed to give architecs the possibility to do lighting studies on their designs. So it might be usefull to check out those raytracers and to see what algos they use. I also seem to remember that those ‘acurate lighting’ raytracers are VERY slow :frowning:

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Edit: also, every shader imaginable could be created with just 3 variables:

Color, bumpiness, and transparency

what about spec? diffuse amount? hardness? reflectivity?(is that a word?) etc…