Emulating soft edges on hard-edge models? (Possible?)
polycounter lvl 19
Hello 
I swear I've worked with an engine that has this capability in the past and I am hoping you folks can help me find out the name of this technique, so I can read up on it.
Have you ever seen or worked with tech that could control edge softness right in the engine? So if I have a hard edge in Max on export (each face is a seperate smooth group, for instance) the engine can emulate a soft edge?
Source can do this with BSP, but I am not sure how is done and assume they just cut the BSP with additional edge loops.
So if you imagine making a simple 6 sided cube where each edge is hard, you'd be able to tell the engine to render those edges soft (as if they're rounded or beveled) and from there control how soft or hard it is.
I swear I've worked with an engine that has this capability in the past and I am hoping you folks can help me find out the name of this technique, so I can read up on it.
Have you ever seen or worked with tech that could control edge softness right in the engine? So if I have a hard edge in Max on export (each face is a seperate smooth group, for instance) the engine can emulate a soft edge?
Source can do this with BSP, but I am not sure how is done and assume they just cut the BSP with additional edge loops.
So if you imagine making a simple 6 sided cube where each edge is hard, you'd be able to tell the engine to render those edges soft (as if they're rounded or beveled) and from there control how soft or hard it is.
Replies
Did you want to do this as a sort of LOD method? Like softening the edges as the object comes into view?
think this is what you mean
Adam. For starters you can check some solutions already available for regular renderers. Max used to have a plugin exactly for that, and now MentalRay has an architectural shader doing exactly this too. (ever monder how come shitty arch wiz models look great when rendered? Heres why!)
I have seen it done realtime too, kinda cool.
As for hacking it manually : render the hard edged lowpoly into a smooth edged lowpoly, and have fun blurring the edges in photoshop!! Works great.
Hope this helps!!
pior - can you elaborate? I'd like to have a few links handy if possible.
Unless you're talking specifically about BSP geometry created in an arbitrary level editor.
Anyone remember f-edge? It was also a renderer-only solution.
Might be too expensive for in-game use, not sure.
Basically the engine calculates two sets of normals per model, the first set is the hard edges, the second set is smoothed normals. Then it masks the edges of the model, displaying the smoothed normals at only the edges, and the hard normals along the flat faces. Giving the model a beveled look without the bevels, and without a normal map.
Hmm, interesting. How expensive is that technique? Would be interesting to know if it was actually more efficient to just bevel the edges instead of using a shader, or vice-versa...
I've not used this technique in a shader myself, I just thought it was interesting as well.
i think we are going to see it more and more.
i was watching a video the other day showing this in a game currently in production that takes advantage of this technology but can't remember which and can't find it now.
maybe you mean something like that ?
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also look what i stumbled upon. this guy is talking about point cloud data technology.
it is quite interesting. he talks in layman's terms at least early on but this actually could be the future.
Polygons is only a way to manage complexity because we need to at the moment after all. People seen lots of technologies fly by understand this. Those who were born and grew professionally in the polygon generation might find it a bit unbelievable.
Unlimited Detail Technology
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there is also part 2
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What did you found out about the latest Dirt game?
glad there is already a thread, i'll go check it out!
regarding Dirt, i found this.
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