You can select polygons that use per-poly UVs by choosing the Select by Polymap command ( View > Selection > Maps > Select by Polygon Map).

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1 UV Texture What is UV Mapping? Sometimes, when mapping textures onto objects, you will find that the normal projection mapping just doesn t work. This usually happens when the object is organic, or irregular in shape. For those occasions, there s UV Mapping! UV Mapping adds two extra coordinates to the points in your object; those on the U and V axis, running horizontally and vertically through a flat plane on which you can paint your texture. Since the coordinates are assigned to points, it s essentially as if that painted texture was fixed to the surface of the object, with pins where all the points are. No matter how irregular your object is, or how it moves or flexes, those pins stay in place, and the texture stays right where you put it. Technically, it s not as accurate as projection mapping, because the texture is really only exact at those points, and merely interpolated everywhere else. But it s close enough!the trick is to make the map first. LightWave has many tools to help you do that. What is Per-polygon Mapping? Per-polygon UV Mapping, or Poly Mapping, was introduced in LightWave 6.0b as a way to handle discontinuous UVs. (Without some kind of handling, they would cause the entire image map to appear backwards and squashed onto a single polygon at the map seam. Not a pretty sight.) They were superseded by the current UV Mapping tools in LightWave 6.5, so unless you are working with a model that was mapped before that, there s really no reason to use them; the new tools are much more elegant and flexible. Unlike UV Maps, Poly Maps cannot be edited with the normal Modify tools used in the rest of Modeler, because they are not continuous. Instead, they are locked snapshots of some UV Mapping of a polygon. So any operation on a vertex must also specify which polygon s view of that vertex is being edited. You can select polygons that use per-poly UVs by choosing the Select by Polymap command ( View > Selection > Maps > Select by Polygon Map). Map Types UV maps can be of several different types explained here:then choose the type of projection you wish to use from the Map Type list. They correspond to the standard projections you may already be familiar with. Planar The first, Planar, simply looks at the object from one of the three axes (X, Y, or Z.) What you ll get looks just like what you see in one of the Orthogonal viewports, but resized to fill the square of the UV space. If you choose X, you ll get what you see in the Right or Left viewport. If you choose Y, you get what you would see in the Top viewport. If you choose Z, you ll get what you see in the Front or Back viewport.

2 Cylindrical The second, Cylindrical, gives you the same effect as you would get from a camera that rotated around the object, (sort of like having your teeth x-rayed) using the axis you chose as the center of the rotation. So, if you choose X, the camera will rotate around a pole going from left to right, and the top of the map will be the right side of the object. If you choose Y, the camera will rotate around an upright pole, and the top of the map will be the top of the object. If you choose Z, the camera will rotate around a pole going from close to far, and the top of the map will be the back of the object. Spherical The third, Spherical, behaves as if all the points are fastened to the inside of a sphere, and then the sphere is laid out flat. The poles of the sphere are on the axis you choose. So, if you pick X, the poles will be at the right and left, and the top of the map will be a few polys on the right side of your object. If you choose Y, the poles will be at the top and bottom, and the top of the map will be a few polys at the top of your object. If you choose Z, the poles will be close and far, and the top of the map will be a few polys on the back of your object. Atlas

3 The fourth Mapping method, Atlas, will call a slightly different dialog, because it has different tools. Atlas spreads the UVs out, so that none of the polygons overlap, and there is a minimum of distortion. This is good, if there s no shading from poly to poly. It s not so good if you need to shade smoothly over a number of polys, because it can be very difficult to paint on. You ll have to decide according to your needs. Relative Gap Size But, because the polys become separated in Atlas mapping, instead of choosing an axis (which would be meaningless), you can choose how much space should be left between groups of polys using Relative Gap Size. Segment by Surface, Segment by Part This option allows you to choose whether the polys should be separated by Surface or Part. (Segment by Surface, Segment by Part.) It s recommended that you enable these, if you have a number of polys in a surface or part group that will be getting the same color, because it can make it easier to paint.

4 However, there can be problem areas on a UV map that require special treatment. UV maps can have edges that are open in a map but closed on the mesh. A single edge on a mesh can be two edges on a map, or a discontinuous edge. These edges are usually along the UV unwrap seams. This usually depends on the UV unwrapping method and the UV editing done, which means that each UV map is unique to every mesh. Discontinuous edges usually surround a so-called UV island. A single UV map can contain multiple UV islands. These UV islands can be rotated and positioned freely in the UV space (by you, or using unwrapping methods like Atlas). A single island or even a single polygon can also be part of multiple UV maps (with different positions and orientations in each UV map). Subpatch Interpolation Usually Subpatch interpolation behaves differently on the outer edge of a mesh than inside a mesh. Since discontinuous edges are outer edges relative to a UV map or UV map island, but are inside edges relative to the mesh, it is not always possible for LightWave to automatically perform a correct Subpatch interpolation over discontinuous edges or over edges that are shared by multiple UV maps. For these types of situations, the following interpolation types have been offered to get the least distortion out of a UV map. Interpolation Type Linear - The UV map is interpolated linearly, most similar to the original mapping option and does not use any subpatching at all.

5 A UV map with two UV islands enclosed by a 3rd large UV island. Linear Interpolation Mode The edges on the very left and right of this UV map are discontinuous, as are the edges along the two small islands in the centre. In this case the biggest problem is that some vertices are shared by all three UV islands. This makes many of the interpolation- methods fail. The situation would be even more severe, if each UV island was in its own UV map.

6 Subpatch - All Edges are interpolated along the subpatch lines, as if the UV map was a subpatch mesh. (Note that the discontinuous edges do not line up.) Subpatch Interpolation Mode

7 Linear Corners - Corner-Points that are along the outer edge of the UV map, but not the edge of the mesh, are interpolated linearly. Notice that it looks better than subpatch, but the discontinuous edges still do not meet up. Linear Corners Interpolation Mode Linear Edges - Edges that are along the outer edge of the UV map, but not the edge of the mesh, are interpolated linearly. Discontinuous Edges now line up, but due to lack of cubic interpolation, some distortion may still occur.

8 Linear Edges Interpolation Mode In this special case only the Linear Edges method would allow for well aligned discontinuous UV edges. However you would have to allow for some distortion along these edges. Across discontinuous edges: Interpolation occurs along discontinuous edges. This method usually provides less distortion along discontinuous edges. A discontinuous edge can be considered a point that shares two separate polygons on a mesh, yet falls on the edge of the UV map so the two polygons are on opposite edges of the UV map. This option lines up the points so the two edges meet up. Please note that this option does not work across multiple UV maps.

9 Across Discontinuous Edges Interpolation Mode If heavy scaling is used or parts are rotated, Across Discontinuous Edges can produce errors. However, this solution is recommended first, since most of the time, the least distortion occurs at discontinuous edges. The Subpatch Interpolations can be further edited in the Assign UV Coordinates window and the Vertex Maps Panel. Axis Choose the axis you wish to align your UVs to: X, Y or Z. Settings In addition to choosing the axes, you can also decide whether to leave the Center and Size settings on Automatic, or to adjust them Manually. If you click on Manual, the Center and Size fields will become active. For most purposes, it s recommended to simply leave them on Automatic. Once you have a UV Map and are ready to paint it, don t make a screenshot, which will be of poor quality at best, and will need to be manipulated before you can use it. Instead, go to File > Export > Export Encapsulated Postscript, choose Texture UV from the View field, and make an.eps file, so you can have clean, high-resolution maps. New UV Map Make UVs ABF Unwrap UVs Flip UVs Transform UV Poly Map

10 Point Map