Meshing Description
Sunday, March 25, 2018 8:30 PMOverview
The Meshing mode is where you import external images of PNG format into your project. Mesh regions are then created from your image. These mesh regions serve as body parts to your animated character. Meshing mode allows the user to perform various mesh operations on the mesh regions, including sculpting, growing, subdivision, cutting and more. Well defined meshes result in well behaved character deformations.
Input Image
The image required for meshing should be square and have the body parts laid out in a non intersecting fashion. You typically prepare this image in the paint/raster/vector art program used to draw the character. Make sure the background is transparent and export the image as a PNG file. The dragon image shown above is an example of how the body parts of your image should be placed.
Meshing Toolbar
The toolbar buttons at the top of the window allow you to carry out various functions related to creation, resolution and boundary definitions of the mesh regions.
Import Image
This imports a new image into the project. You will have the option of creating new mesh regions from the body parts of the image.
Remesh Texture
Clicking this button will pop up a pane allowing the user to remesh the image. This results in the creation of new mesh regions from the body parts of the image.
The application will attempt to create mesh regions from the image based on the input options. You should pick appropriate resolutions for the X and Y values of the grid. The grid resolution will determine how fine the meshing grid is. This will in turn determine how detailed the resulting generated mesh regions will be. The higher the detail, the better the deformation quality. However, setting too high a resolution will cause slowdowns in rigging and animation and might not be appropriate for the various game engines you are exporting the animation to.
Boundary Remesh
Sometimes when you are generating mesh regions, 2 seemingly separate body parts might be merged together in the same mesh region. This typically happens because the 2 body parts in the image are in close proximity to each other. There are various ways to solve this problem. One solution is to remesh the image again with a higher resolution at the cost of performance. The other solution is to use the Boundary Remesh tool. Click this button and the application will allow the user to paint out triangles that define a cutting/separation boundary between the 2 desired regions.
In the example above, the triangles painted white are the separation boundary. After the boundary has been specified, click Remesh to generate the new mesh regions.
Meshing Operations
The buttons on the lower right of the window allow the user to perform various meshing operations on the selected mesh region.
Grow
This grows the selected mesh region outwards in all directions. Use this to expand the mesh region.
Subdivide
This adds detail to the selected mesh region by subdividing the triangles in the region.
Sculpt
Sculpt is a mode that allows the user to manually add and remove triangles to the selected mesh region.
Region Remesh
This performs similar operations as the Remesh Texture button but at a local mesh region level. It allows the user to remesh a specific mesh region as opposed to remeshing the entire image.
Repacking Texture Atlas
You can repack the character's Image Atlas to optimize for space and efficiency. To perform this operations, click on Import -> Repack Texture Atlas:
A new window will popup with repacking options:
Pick your new Image Width and Image Height. Padding is typically set to 0 unless you want more spacing when repacking the different mesh regions.
After clicking on Ok, it will attempt to repack your body meshes. If successful, it will show the Remesh window again. You will need to Remesh since the meshes are now packed into different positions on the new texture atlas.
Go ahead and Remesh your new mesh regions. This operation will also try to automatically sync up your already rigged regions with the newly packed mesh regions. If you experience artifacts during the repacking process, you will need to manually remove the regions with artifacts in ther rig and add them back in.
Advanced Meshing Operations
There are additional meshing operations you can perform in Meshing Mode:
- Custom Poly Allows you to create + edit a custom polygonal mesh ( non-blocky shape )
- Merge Merges 2 separate meshes together
- New Allows you to sculpt/create a brand new blocky triangulated mesh
- Delete Removes the selected mesh
Custom Polygonal Mesh
You can manually create a custom polygonal mesh by clicking on the Custom Poly button. If the selected mesh is already of custom polygonal type, then you will also have the option of editing the current polygonal mesh ( clicking on the Sculpt button also goes into custom polygonal mesh editing mode if you have selected such a mesh )
The mesh creation screen looks like this:
During creation time, you should use your mouse and click to specify the boundary points of your new polygonal mesh. There are 2 options availabel:
- X Res Defines how detailed the resulting mesh is in the x direction
- Y Res Defines how detailed the resulting mesh is in the y direction
To finish mesh creation, make sure to close the polygon by clicking back on the first point of your boundary.
With that, the mesh is created:
You can peform the following:
- Add Vertex SHIFT+CLICK on the center of a triangle to subdivide it from the middle. SHIFT+CLICK on an edge of an interior triangle to subdivide it along an edge
- Remove Vertex CTRL+CLICK on an interior vertex to remove it from the mesh
Slice
You can Slice a polygon into 2 new polygons using the Slice feature. Plot our ( via Left Mouse Clicking ) the dividing slicing curve of your existing polygon. The slicing curve must only intersect the existing polygon Twice. In other words, this operation is designed to split a polygon exactly into 2 new polygon meshes.