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Mesh Preparation and Texture Coordinates
Your mesh will need to have texture coordinates to display a texture. The geometric primitives, such as cube, cylinder, etc, have those coordinates, though the more complex teapot and Earthling do not. If your mesh is imported, it will have texture coordinates if they are present in the input file.
If your mesh does not have texture coordinates, you can create them via the Texture submenu. Go to a frame in the shot that has a nice view of the object, select Frozen Front Projection, then Remove Front Projection and Crop Texture Coordinates. Since the mesh will generally occupy only a small portion of the image, it will use only that small portion of the texture map, wasting much of the available resolution. The Crop operation will expand the limited texture coordinates to the full 0..1 range, and thus the entire texture image.
A particular limitation of creating texture coordinates using camera mapping is that only the half of the object facing the camera can be used, since the back side will have the exact same coordinates. The resulting mapped object will appear to have a plane of symmetry with the identical texture on each half.
The geometric primitives have carefully-chosen texture coordinates that use the whole image (as possible) without artificial limitations.
Important : Make sure all meshes are subdivided until each triangle covers only a relatively small portion of the screen & 3-D environment. This is especially true of tracker meshes.
360VR . When doing texture extraction from 360VR shots, be sure that the meshes are especially well subdivided, especially when using blocking meshes. Inadequate subdivision can cause seams to open in the extracted texture, because straight lines in the 3D environment are not straight in 360VR images.
Many of the calculations during texture extraction are performed only once per triangle, not once per pixel, which saves a tremendous amount of time. However, if triangles are too big, perspective changes from one end to the other will cause unnecessary blurring. (The interior pixels of a triangle use bilinear interpolation, instead of the full perspective transform and lens distortion compensation used for the vertices).
If you are extracting from a tracker mesh, you can add additional trackers in problem areas. Use Track/Add Many to increase tracker density before meshing. Or use Punch In Tracker mode in the perspective window to add individual later trackers to the mesh.
Alternatively, you can write your mesh to an OBJ file, increase its density in a third party application, perhaps with smoothing, and reimport it for texture extraction.
If you are using geometric primitives created in SynthEyes, such as plane, sphere, etc, you can control the segment counts using the # button on the 3-D panel.
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