Head Rigs with Quad Mesh Best Practices?
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WatchMotion
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Head Rigs with Quad Mesh Best Practices?
I know it's super early to ask but after seeing Victor's awesome demos I've been playing with the quad mesh on a vector head rig with some really great results and then some not so great results. Does anyone have any best practices for building the mesh? I've been experimenting with edge flow/ 3D topology ideas too. Thanks!
Re: Head Rigs with Quad Mesh Best Practices?
It depends on what you're deforming. With a human head, you want to follow the shapes in the face. Study the flow in some of Victor's examples, notably around the mouth, eyes and eyebrows.
I find that for most parts of the face, quads work well but for areas with sharp corners, like in the corners of the eyes and mouth, triangles work better. Thankfully, you can freely mix quads and triangles in Moho 13.5!
There are two ways to work with mesh creation:
1. You can have give Moho a filled contour shape and guide lines inside the shape for the details. When you select Triangulate 2D Mesh, Moho will generate the polygons needed. Be aware that all the polygons will created as triangles.
...or...
2. You can draw all your quads and triangles paths manually, and then run Fill Quad Mesh to create the shapes. I prefer this method because it lets me fully control the density and accuracy of the mesh. (Note that Fill Quad Mesh will alert you if there are invalid polygons or points in your drawing, and it will try to indicate what you need to fix. Very helpful!)
In general, I find it's better to create only the polygons you need, and not too few or too many shapes. Too few will limit how you can animate the face and the quality of the deformation; too many will be difficult and too fiddly to animate quickly.
Tip: After drawing your paths (for either method #1 or #2,) make a duplicate of the layer, and run the mesh creation command of your choice on the duplicate. This way, if you need to further edit the mesh, you can go back to the original drawing which should be easier to edit.
Hope this helps.
I find that for most parts of the face, quads work well but for areas with sharp corners, like in the corners of the eyes and mouth, triangles work better. Thankfully, you can freely mix quads and triangles in Moho 13.5!
There are two ways to work with mesh creation:
1. You can have give Moho a filled contour shape and guide lines inside the shape for the details. When you select Triangulate 2D Mesh, Moho will generate the polygons needed. Be aware that all the polygons will created as triangles.
...or...
2. You can draw all your quads and triangles paths manually, and then run Fill Quad Mesh to create the shapes. I prefer this method because it lets me fully control the density and accuracy of the mesh. (Note that Fill Quad Mesh will alert you if there are invalid polygons or points in your drawing, and it will try to indicate what you need to fix. Very helpful!)
In general, I find it's better to create only the polygons you need, and not too few or too many shapes. Too few will limit how you can animate the face and the quality of the deformation; too many will be difficult and too fiddly to animate quickly.
Tip: After drawing your paths (for either method #1 or #2,) make a duplicate of the layer, and run the mesh creation command of your choice on the duplicate. This way, if you need to further edit the mesh, you can go back to the original drawing which should be easier to edit.
Hope this helps.
Last edited by Greenlaw on Tue Jun 08, 2021 4:05 pm, edited 1 time in total.
D.R. Greenlaw
Artist/Partner - Little Green Dog | Little Green Dog Channel on Vimeo | Greenlaw's Demo Reel 2020 Edtion
Artist/Partner - Little Green Dog | Little Green Dog Channel on Vimeo | Greenlaw's Demo Reel 2020 Edtion
Re: Head Rigs with Quad Mesh Best Practices?
Another tip: When you're creating a mesh, also think about the regions you want to pin down with points, as well as the areas you want to animate with points. This will keep your animations from looking too 'squishy'.
D.R. Greenlaw
Artist/Partner - Little Green Dog | Little Green Dog Channel on Vimeo | Greenlaw's Demo Reel 2020 Edtion
Artist/Partner - Little Green Dog | Little Green Dog Channel on Vimeo | Greenlaw's Demo Reel 2020 Edtion
Re: Head Rigs with Quad Mesh Best Practices?
Final tips:
Think about how Moho uses the mesh layer to warp an image...
1. Moho will only render the image where it has a filled shape. This means, you can create holes in your mesh, which is useful around the eyelids and mouth. You may then place 'un-deformed' versions of the irises, teeth, etc., in layers behind the holes. This also means the outer boundary will clip your image with a sharps edge. If you need a softer edges, you need to make the outer boundary of your image transparent and have a soft or anti-aliased edge painted into the image. The mesh's boundary then needs to be slightly larger than the image's edge.
2. Points deform the image, not the lines. This means, it doesn't matter if the lines are straight or curved. The strength of each point falls off gradually in a circle around the point.
3. In the mesh, the strength value of all the points is evenly distributed. With this in mind, a region with more points will have a stronger influence.
Think about how Moho uses the mesh layer to warp an image...
1. Moho will only render the image where it has a filled shape. This means, you can create holes in your mesh, which is useful around the eyelids and mouth. You may then place 'un-deformed' versions of the irises, teeth, etc., in layers behind the holes. This also means the outer boundary will clip your image with a sharps edge. If you need a softer edges, you need to make the outer boundary of your image transparent and have a soft or anti-aliased edge painted into the image. The mesh's boundary then needs to be slightly larger than the image's edge.
2. Points deform the image, not the lines. This means, it doesn't matter if the lines are straight or curved. The strength of each point falls off gradually in a circle around the point.
3. In the mesh, the strength value of all the points is evenly distributed. With this in mind, a region with more points will have a stronger influence.
Last edited by Greenlaw on Sat May 22, 2021 2:47 am, edited 3 times in total.
D.R. Greenlaw
Artist/Partner - Little Green Dog | Little Green Dog Channel on Vimeo | Greenlaw's Demo Reel 2020 Edtion
Artist/Partner - Little Green Dog | Little Green Dog Channel on Vimeo | Greenlaw's Demo Reel 2020 Edtion
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WatchMotion
- Posts: 28
- Joined: Sun Feb 04, 2018 4:47 am
Re: Head Rigs with Quad Mesh Best Practices?
Thanks a lot, Greenlaw! This is really great stuff, I'll be sure to post some WIPs when I get a chance to deep dive into your tips.
Re: Head Rigs with Quad Mesh Best Practices?
well, this is not a universal matter. It depends.WatchMotion wrote: ↑Fri May 21, 2021 5:11 pm I know it's super early to ask but after seeing Victor's awesome demos I've been playing with the quad mesh on a vector head rig with some really great results and then some not so great results. Does anyone have any best practices for building the mesh? I've been experimenting with edge flow/ 3D topology ideas too. Thanks!
TarhibIT