Java Doc for GeometryInfo.java in  » 6.0-JDK-Modules » java-3d » com » sun » j3d » utils » geometry » Java Source Code / Java DocumentationJava Source Code and Java Documentation

The NormalGenerator adds normals to geometry without normals.

The Stripifier combines adjacent triangles into triangle strips for more efficent rendering.

Geometry is loaded into a GeometryInfo in a manner similar to the GeometryArray methods. The constructor for the GeometryInfo takes a flag that specifies the kind of data being loaded. The vertex data is specified using methods that are similar to the GeometryArray methods, but with fewer variations.

The major difference between GeometryInfo and GeometryArray is that the number of vertices, vertex format, and other data are specified implictly, rather than as part of the constructor. The number of verticies comes from the number of coordinates passed to the setCoordinates() method. The format comes from the set of data components that are specified. For example, calling the setCoordinates(), setColors3() and setTextureCoordinatesParames(1, 2) methods implies a format of COORDINATES | COLOR_3 | TEXTURE_COORDINATE_2. Indexed representation is specified by calling the methods that specify the indices, for example setCoordinateIndices().

Stripped primitives are loaded using the TRIANGLE_FAN_ARRAY or TRIANGLE_STRIP_ARRAY flags to the constructor. The setStripCounts() method specifies the length of each strip.

A set of complex polygons is loaded using the POLYGON_ARRAY flag to the constructor. The setStripCounts() method specifies the length of each contour of the polygons. The setContourCounts() method specifies the number of countours in each polygon. For example, a triangle with a triangular hole would have strip counts [3, 3] (indicating two contours of three points) and contour counts [2] (indicating a single polygon with two contours).

GeometryInfo itelf contains some simple utilities, such as calculating indices for non-indexed data ("indexifying") and getting rid of unused data in your indexed geometry ("compacting").

The geometry utility tools modify the contents of the GeometryInfo. After processing, the resulting geometry can be extracted from the GeometryInfo by calling getGeometryArray(). If multiple tools are used, the order of processing should be: generate normals, then stripify. For example, to convert a general mesh of polygons without normals into an optimized mesh call:

 GeometryInfo gi = new GeometryInfo(GeometryInfo.POLYGON_ARRAY);
 // initialize the geometry info here
 // generate normals
 NormalGenerator ng = new NormalGenerator();
 ng.generateNormals(gi);
 // stripify
 Stripifier st = new Stripifier();
 st.stripify(gi);
 GeometryArray result = gi.getGeometryArray();
 

This method should be considered for advanced users only. Novice users should just use getGeometryArray() to retrieve their data so that the internal format of GeometryInfo is of no concern.

Note: If the texCoordSetMap is not set, multi-texturing is turned off.

If the GeometryArray uses the Initial and Valid GeometryArray methods ( setInitialVertexIndex() and setValidVertexCount() and their cousins) then only the needed geometry is copied into the GeometryInfo.

This method should be considered for advanced users only. Novice users should just use getGeometryArray() to retrieve their data so that the internal format of GeometryInfo is of no concern.

Note: If the texCoordSetMap is not set, multi-texturing is turned off. Only the texture coordinate set at index 0 (if set) will be used. Any other sets specified by the GeometryInfo.setTextureCoordinate* methods will be ignored.

 geomInfo.setTextureCoordinateParams(2, 3);
 geomInfo.setTextureCoordinates(0, tex0);
 geomInfo.setTextureCoordinates(1, tex1);
 geomInfo.setTextureCoordinateParams(1, 2);
 geomInfo.getTexCoordSetCount();