[prev] Texture Maps: 1: Patch Name [next]

Each patch has a unique name, and by default that is "pat" followed by an ever increasing number. You might like to change the names of patches so they are easier to identify when you import them into other packages. For example, all the patches used to surface a mouth could be called "mouth1", "mouth2" and so on.

The name is also used when creating the texture map files for each patch. That way you know which map goes with which patch, and it allows the technical minded to set up some sort of automatic procedure for assigning the maps in your rendering package.

[no zoom]
Figure 113. Patch Name

To change a patch's name, pick it first, then type the new name into the Name field in the Texture Maps panel. Within CySlice there is no limit to the length of a patch's name. But when exported into an IGES file, names are truncated to 8 characters, so you should keep that in mind when choosing names.

2: Map Size

Enter the map pixel dimensions into the X and Y fields. If you want a hint as to the most appropriate dimensions, hit the Map Size button. CySlice will look at the size of the patch, compare that to the density of the polygons, and will come up with dimensions that should save you from under or over sampling too much.

By default the calculated map dimensions are unlimited; they could be very small or very large depending on the patch size and polymesh density. But you can enter values into the Min and Max fields to clamp the calculated map sizes.

[no zoom]
Figure 114. Map Size

Some renderers prefer to have maps with "power of 2" dimensions (e.g. 128, 256, 512, 1024 etc). If you enable the Pow 2 toggle, then whenever the map size is automatically calculated, the next higher "power of 2" dimension will be selected.

For SUBD surfaces, the individual patch map sizes are still required. They determine the relative coverage of each patch in the single large texture map.

To quickly calculate the map size for all visible patches, click on the All Size button, found towards the bottom of the Texture Maps panel.

3: Disp, Color and Norm

Enable the Disp, Color or Norm toggles if you want displacement, color or normal maps for the selected patch.

[no zoom]
Figure 115. Disp, Color and Norm

Calculating the UV color map for a patch takes minimal extra time, but it only makes sense if your polymesh is colored. Color in a PLY file is represented as Color Per Vertex (CPV), which means that each point in the mesh has both RGB and XYZ values.

[click to zoom]
Figure 116. CPV Polymesh, Rendered Patch, UV Map

Figure 116 shows a polymesh with CPV on the left. A patch rendered with both displacement and color maps is shown in the middle. The UV color map, extracted from the CPV polymesh, is shown on the right.

To quickly assign the current Disp, Color and Norm toggles to all visible patches, click on the All Type button, found towards the bottom of the Texture Maps panel.

The black left and right arrows are used to change the orientation of the UV map for the selected patch. Each click of the right arrow button rotates the patch forward by 90 degrees, the left arrow backward by 90 degrees.

You can see the U direction of each patch by enabling the U Dir toggle in the Display panel.

[prev] [top] [next]