( turn on English subtitles )
Hello. In this tutorial, I will explain what a uv_1 map does and how to:
- prepare a garment for uv_1 mapping;
- transfer maps from one mesh to another with Data Transfer modifier;
- set up a reference and manually edit or create a new uv_1 map;
- project certain parts of the mesh on a reference for more accurate results.
WRITTEN TUTORIAL:
PLEASE DO NOT REPOST
While a uv_0 map projects a texture on a 3D mesh surface, a uv_1 map defines how the mesh will deform in the process of adjusting body parameters in CAS.
This is what a uv_1 map looks like ( 1 ). As you see, EA meshes are split along the seams ( 2 ). To get a more-or-less neat result of UV transfer, you need to ensure that there are edges right along any seam on the reference that is covered by the garment’s mesh. Otherwise, UV islands either will be split unevenly or stretched ( 3 ).
There is a number of ways in which you can prepare the mesh in MD for UV transferring:
- Line Tack on Avatar ( starting from MD 7.5 ) ( 1 ). Draw a line along the seam on the garment, double-click to finish. Repeat for the body. Run simulation. Adjust the surrounding area.
- Tack on Avatar ( 2 ). Again, click on the garment first, then on the body. Run simulation. Repeat the same on the surrounding area.
- Line ( 3D pattern ) ( starting MD 7 ) ( 3 ). With this tool, you can create edges wherever you want. Switch mesh display to wireframe ( 4 ), click to start and press Shift to draw a straight line along the seam, double-click to finish. Choose Edit Line ( 5 ), RMB-click on the drawn line and select Convert to Internal Shape ( 6 ). In 2D window RMB-click on the line and choose any of Extend/Trim options ( 7 ). You can also split the pattern with RMB – Cut & Sew on the line ( 8 ).
Do retopology in a way that preserves created edges. Export a reference mesh and File – Append ( 1 - 3 ) it in the scene. Double click on imported s4studio_mesh_1 ( 4 ) and combine the rest with Ctrl J. RMB – Delete ( 5 ) on rig.001 and bone_bone_shape.001.
Select the garment’s mesh, create a new map ( 1 ) and rename it. Go to Modifiers tab ( 2 ) and add Data Transfer ( 3 ). Choose your reference mesh in Source Object ( 4 ) and enable Face Corner Data Transfer. In most cases, the best option for Face Corner Mapping is Nearest Face Interpolated ( 5 ), but sometimes the default one works, too. Select UVs ( 6 ) and uv_1 ( 7-8 ) in both drop-down menus, Apply. Switch to Edit Mode ( TAB ) and check the UVs.
As you see, they are almost perfect. It is not necessary in this case, but you can manually edit UVs by selecting everything ( A ), disabling Keep UV and Edit Mode mesh selection in sync ( 1 ) and Sticky Selection Mode ( 2 ), enabling Snap during Transform ( 3 ) with Vertex for Snap UV element ( 4 ). You can also straighten edges with UVs – Weld/Align – Align X (vertical) or Y (horizontal)( 5 ). Another thing you can do to achieve neater UVs is to subdivide the reference mesh with Subdivide Modifier ( 6 ) before transferring them. It will result in a bit smoother UVs.
To manually create or edit UVs with the help of a reference, append the body, select uv_1 ( important ), assign new material in Materials tab ( 1 ), create new texture in Texture tab ( 2 ), open ( 3 ) Andrew’s CAS UV_1 template image ( link in the description ), switch Viewport Shading to Texture ( 4 ). Switch to Edit Mode, select everything and set the background image ( important ) ( 5 ). In UV editor window hit S to scale, X to scale horizontally, type 0.5 to shrink in half. Then G to move, X to move horizontally, type 512 to center the UVs. Move and resize garment’s UVs the same way. In Object tab switch Maximum Draw Type to Wire ( 6 ). Now you can use your reference’s UVs as a guide in editing or creating uv_1 map for the garment.
Once you’re done, don’t forget to scale and move the UVs back. S and X to scale horizontally, type 2 to double in size. G and X to move horizontally, type -512 to move back in place.
If the result of Data Transfer is inaccurate to the point of being noticeable in CAS, try projecting certain parts of the mesh on the reference and repeating the process. First, select, separate ( P – selection ) ( 1 ), duplicate the part ( Shift D ) ( 2 ) and hide the original ( 3 ). Optionally subdivide the reference mesh. Select visible copy and switch to Edit mode. You can project something on the surface of other objects with Shrinkwrap modifier, but it doesn’t always give good results, so let me show you another way. Enable Snap during transform with Face ( 4 ) selected and Project individual element on the surface of other objects ( 5 ). Make sure you are in the front ( 1 ) orthographic view ( 5 ), press G to project. Transfer uv_1 the usual way. As you see, they are significantly better ( 6 ).
Now, we need to bring the projected part back to its original form. In Data tab unfold Shape keys and add Basics with + ( 1 ). Unhide original, select it, shift-select the copy, choose Join as Shapes ( 2 ). Select the added option and drag Value to 1 ( 3 ). Delete Basics first, then the other one with - ( 4 ). Delete the original part. Join everything back ( Ctrl J ). Thank you for watching.
THANK YOU FOR READING.
If you have any questions or suggestions to improve this workflow, please leave them under the video / in replies to this post / in the ask box or message them privately on tumblr / via e-mail ( [email protected] ).