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Alan7996

What about something like "perfect absorption"? Do our reflective functions consider the amount of light being absorbed by the material?

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saphirasnow

Could the range of possible materials be considered in a 2D space with the two dimensions "absorbed vs. reflected" and "direction of reflection," or is there added complexity that prevents this?

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YutianW

Why's does the moon have a retro-reflective phenomenon? I know for reflection light on the bicycle back, it has a zig-zag like material so that it makes the light reflect back to where it came from. But how about the moon?

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kkzhang

If materials are just represented by giving them different reflection functions, then how would we represent a sphere with a rugged surface? For example, we had a sphere made of stone, and we could see this effect on the sphere based on lighting, but wouldn't the geometry still be perfectly smooth? Is this more of a modeling problem than a graphics problem?

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Starboy

Can all possible reflection functions be decomposed into the combination of one or more basic reflection functions?

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tianez

Modeling material through reflective function provides a way to express and approximate different surfaces. When trying to render realistic photos, can we find a way to generate a combination of reflective functions to represent a surface, assuming that we define the invariants correctly?

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dl123

When doing rendering in computer graphics, do we always assume that the objects are ideal specular or ideal diffuse?

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snaminen

How is ideal diffuse at really low levels different from absorption?

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embl

How much of physics can be realized in computers?

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Oh_skr

Are the reflection functions linear? Can we use bilinear interpolation for a mixture of two materials?

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MrRockefeller

what are the factors that determines reflection functions? I can only think of material and concave/convex mirror on top of my head. My guess of the moon has nothing to do with material, is it because of its distance? How to quantify this

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BlueCat

I am wondering how people know these reflection patterns which just match with what we saw in our lives? Did people do a lot of experiments on finding this pattern?

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minhsual

How are these reflection functions determined?

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Coyote

It seems like these actually cover a decently large portion of materials, since I feel as if most other materials would be combinations of these functions. However, is there a way to derive these reflection functions or do they need to be obtained by trial and error?

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anon

Is there a general equation for determining the glossy specular curve? Is there a lower bound for what would generally be considered "a majority" in that case?

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Concurrensee

Is these reflection functions calculated by specialized hardware?

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ddkim

I'm confused on the moon being a retro-reflective source. Does the moon reflect the light it gets from the sun back to the sun?

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corgo

Can you elaborate a bit more on the retro-reflective aspect of the moon?

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birb

Can you tell that an object is retro reflective if you are not standing in the direction of the light source?

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spidey

I am a bit confused about retro-reflective light sources, I understand things like the moon do reflect light back to the source, but how is that visualized in a computer model scene?