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


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?


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?


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?


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


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?


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


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


How much of physics can be realized in computers?


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


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


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?


How are these reflection functions determined?


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?


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?


Is these reflection functions calculated by specialized hardware?


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?


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


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


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?