so i managed my first representation of a highpoly dynatopo render as a lowpoly render in cycles, via normalmaps… the idea of this thread is to start from there, and try and test more possibilities to get the best possible results… so i begin with my first result:
right is the original highpoly dynatopo (1.5 mill) that carries a vertex paint which is used to drive the shader.
left is lowpoly (32k) with uv, normal map and a texture that contains the vertex paint of the highpoly dynatopo and thus can create the same shading effect.
i have shown this image in my sketchbook and michalis said and asked:
… we better discuss it a bit further.
So, you did bake the normal maps, where? In zbrush? If so what compatibility method did you use?
How did you unwrap it? How unwrapping looks like?
for this exported the dynatopo to zbrush, i did the lowpoly with zremesher, and unwrap in zbrush too. the unwrap is one big piece, with the seam at the backside. i guided the placement of seam by blue color… i imported lowpolymesh into blender. in zbrush i made a made a morphtarget for the lowpoly, then subdivided it to have more polyes than the original, and projected it. then i went down to the llowest level, switch the morphtarget back and let calculate normal map, with flip “g”. then i exported the normal map (i think with flip v) and put it into the shader in the normal sockets… for the vertexcolor, i did bake the highpoly vertex color onto a texture of the lowpoly mesh using blender internal with a white materail on the highpoly and the baking option “to texture” and checked “vertex paint”…
(michalis)
So, on the left, the low poly + normal maps.
- I think it is a little overdone, maybe a little less strength on the normal node?
- Cycles does not like low poly meshes! It is the termination issue, you see. These artifacts between light and shadow. A well known issue on many pathtracers. So, adding a subsurf (for rendering needs only) always help.
Subsurf then, one or better two subd levels. Fine for previewing. But, 2 subd levels, an opportunity to use them for real geometry.
Two options,- you choose to export the third subd level from zbrush (is not called zero level there). Of course, you choose to bake normal maps from this level (like in blender, bake from multires technique). If you render from the first subd level, a not very natural effect will happen)
- Bake displacement map from the first subd level. If this gonna be applied on a 2x subsurf, this is the third subd in zbrush. Go there and bake the appropriate normal map. (from this level). Combine displ (modifier only) plus normal maps (renderer)
- yes i enlarged the strength of the normal map, as on 1 it was too weak. i overdid a tad, i agree.
- yes, the artifacts light shadow are what is annoying, would be nice to remove them. yes, i had tried with the subsurf, but then where is the point to do all the work. i mean when i apply a subsurf level2 on the 32k mesh, i have about half million polygons, it renders not faster essentially than the original dynatopo … displacement i have not tried yet, but same question, for displacement neads subsurf and level2 might be not enough, and then i would come over 1.5mill polygons…
ok, lets start discussion, and tests!