Q about 'Reflection Map Resources - Outdoor Pack One'

Hera

Hi!

I have a Q about this product

http://www.daz3d.com/reflection-map-resources-outdoor-pack-one?utm_campaign=(10/31/13¨

It looks as if the reflection can come both from the surroundings AND a map at the same time, (something I´ve been wanting for ages) am I right in that? And how does it work?

DimensionTheory

I'm not quite sure what you mean by "at the same time", can you explain what effect you're trying to go for? It's certainly possible to use the Reflection Dome for raytraced reflections while using that same map for Environment Mapped reflections if that's what you mean. That would let you use raytraced where it's needed and Environment Maps where you want the speed, with them both matching up since they use the same map. The domes might not line up with the direction of Environment Mapping but you can always rotate them.

Richard Haseltine

I think Herakleia wants to have near objects reflected while using an environment for distance, which presumably the Phantom domes do. I did once use Shader Mixer to set up a shader that would do that directly, no dome needed, but I'm not sure it would have been any better than a real dome in effect.

DimensionTheory

The Environment Map at a distance thing isn't something that's covered by the product, it's certainly possible but as you said it would require a special shader to be made (which I could do it would just be some more work). My intention for the product was to provide a solution that was easily applicable to the stuff that's already available on the market, a custom shader would take away from that a bit because applying any new shader would mean the material would have to be rebuilt for each surface it's used on. Presets here won't change the way materials look aside from their reflections.

Hera

Okay - I blame my English for being completely lost here, both when it comes to expressing myself and understand what's being said here. So I'll try again.

What I mean is that I'm looking for something which combines ray-trace with a map, that is, when there's something to reflect, that gets reflected, and when there's nothing, the map gets reflected instead of just render a dark surface. As if the map was a surrounding object.

After all, it's not always possible to use domes, especially when working with distant objects. And just using a map gives often very unrealistic effects, like suroundings not being reflected and reflections being too bright.

Richard Haseltine

Unfortunately my solution to mixing a map and real reflections still relied on setting a maximum distance, beyond which it was assumed there was nothing to reflect. You could do the same with a dome by scaling the dome up so that it enclosed the contents of your scene.

Hera

I can try that, thanks :) And I hope one day my combo will be possible to create

rassahah

If you can use shader mixer, you could try that one: https://sites.google.com/site/millighostmix/home/maptrace-brick
I wonder if this kind of stuffing a shader mixer brick into a single file actually works...

DimensionTheory

Richard Haseltine said:

Unfortunately my solution to mixing a map and real reflections still relied on setting a maximum distance, beyond which it was assumed there was nothing to reflect. You could do the same with a dome by scaling the dome up so that it enclosed the contents of your scene.

There should be ways to do environment mapping and raytraced reflections in shader mixer by using ray depth brick to set raytracing only up to a certain number of reflection bounces before switching to environment mapping when it returns null. If ray depth is 0 then it would just render environment maps, if it's 1 it would reflect diffuse objects in your scene then use environment mapping for areas of the surface returned as black. While a depth of 2+ would reflect other reflective surfaces (like mirrors pointed at mirrors) that number of times before using environment mapping where it ends.

Richard Haseltine

I hadn't thought of that - as I recall I used the distance brick, but I can't recall how now.

millighost

With reflected objects "in front" of the environment map:

DimensionTheory

That shader setup looks like it works well to provide the visual effect but I don't think that it would provide any speed increase in areas using the environment map, since it is raytracing the whole surface and using the result as a mix. Were you to restrict the raytracing by distance like Richard had or by ray depth like I mentioned, you could ray test to determine if that part of the surface is raytracing a reflection and map the environment only where it's not.

millighost

DimensionTheory said:

That shader setup looks like it works well to provide the visual effect but I don't think that it would provide any speed increase in areas using the environment map, since it is raytracing the whole surface and using the result as a mix.
Of course it traces the whole surface. I do not think there is a way to determine if a traced ray would hit a surface (or if it would not hit a surface) without actually raytracing it.

Were you to restrict the raytracing by distance like Richard had or by ray depth like I mentioned, you could ray test to determine if that part of the surface is raytracing a reflection and map the environment only where it's not.

You can limit the ray tracing distance on the trace node. I did not understand the part with the ray depth, though.