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BUZZFX
11-26-2005, 07:04 AM
I saw in another application they used a vertex weight map to blend out the influence of the grass near the path. Is this possible with C4D?

BUZZFX
11-26-2005, 07:07 AM
In the example I saw, the grass became shorter as it approached the path.

Per-Anders
11-26-2005, 07:42 AM
just use the confusingly named "Vertex Map" shader, or a plugin like stormtracer which will render individual blades based on a vertexmap (or pretty much anything else). the issue is that your mesh is very low resolution, vertexmaps will only blend as good as you see in viewport so you might want to add some definiotn around the edges of your pathway.

BUZZFX
11-26-2005, 05:22 PM
just use the confusingly named "Vertex Map" shader, or a plugin like stormtracer which will render individual blades based on a vertexmap (or pretty much anything else). the issue is that your mesh is very low resolution, vertexmaps will only blend as good as you see in viewport so you might want to add some definiotn around the edges of your pathway.

You see the "Vertex Map Shader" in the Object Manager, but how do I use this to make the grass blend into the path or is this not used for that? How come I don't see anything blending at all? Am I using this correctly?

Per-Anders
11-26-2005, 06:05 PM
there's no vertex map shader in there. you simply have a vertex map in there which is what a vertex map shader uses. a shader is a procedural texture used within a material. i'd recommend reading the manual on this.

STRAT
11-26-2005, 06:42 PM
i'd approach this using an opacity map on the path object. and opaticy map with fades at the edges. i've done this method to great effect numerous times in the past. nice and easy :)

ooo
11-26-2005, 09:11 PM
i'd approach this using an opacity map on the path object. and opaticy map with fades at the edges. i've done this method to great effect numerous times in the past. nice and easy :)

The opacitymask is indeed great for a natural edge of the path but for a natural falloff for the grass you still need a vertexmap I think... or did I mistunderstand you?

odo

STRAT
11-26-2005, 09:29 PM
The opacitymask is indeed great for a natural edge of the path but for a natural falloff for the grass you still need a vertexmap I think... or did I mistunderstand you?

odo

an opacity map can give you a natural gradiented fall off or a hard edge fall off.

for a gradual blend from the path to the grass you fade out or gradient the edges of the opacity map. for a natural gravelly edge from path to grass you paint in a gravelly edge to the opacity map.

or did i missunderstand you?

rob rhodes
11-26-2005, 09:31 PM
strat in what way do you use opacity maps? Are you talking about using photoshop and alpha channels or do you mean using something inside cinema/BP? Do you think you could go into a bit more detail as im interested in this as well. Cheers

STRAT
11-27-2005, 07:02 AM
i mean painting your opacity map in photoshop first to determin what kind of fall off you're after. i dont have past examples open to me at home, but i'll book mark this thread and try to better explain (with examples) early this comming week in work

lllab
11-27-2005, 07:41 AM
i think he means that the grass gets a different color when it gets closer to the path.

i also would use a vertex map or a handpainted map. use the mix shader to blend 2 slightly different shaders tehn.

cheers
stefan

FantaBurky
11-27-2005, 08:15 AM
OOOO, I've tried this before multiple times for some stuff I made for Grand Theft Auto Vice City. I have two ways. One which will work for you but not for games. Which is, create a texture in the same "format" as your plane (but at high quality, like 1000x1000). And paint from above in PS how you want it, use like the layer of dirt to cover the whole thing. Then add the grass and erase the parts you want to be dirt instead. Then use that as a texture. I think this is the best way for you, as you are using big tiles.

Or, the way I do for the game. This requiers a bit of uvmapping experience. You take the polygons which are dirt in your scene, and use extrude inner, to get polygons which are half as big as the dirt polygons to be the blendning polys. Then you create a texture in photoshop which blends the two (from grass to dirt as you want), and you uvmapp it on the created polys. Kinda difficult on your scene as it has big tiles, but could be nice to know for later.

STRAT
11-27-2005, 08:16 AM
or the path changes even. as the path edges get closer to the grass they merge in with a smooth visible transition, or if prefered, a hard gravelled edge. not the straight line edge as unrealistically normally used.

ooo
11-27-2005, 12:30 PM
an opacity map can give you a natural gradiented fall off or a hard edge fall off.

for a gradual blend from the path to the grass you fade out or gradient the edges of the opacity map. for a natural gravelly edge from path to grass you paint in a gravelly edge to the opacity map.

or did i missunderstand you?

Sorry my mistake. i understand what you mean. I was just referring to a 3D grassfield (DPIT or whatever) with vertexmap distribution, not a 2D material. Should have looked better at the orginal post :)

odo

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