3D Transformations & Scene Setup

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CONVERT_COORD: Transforms coordinates to and from the Direct Graphics coordinate system.

COORD2TO3: Returns 3D data coordinates given Direct Graphics normalized screen coordinates.

CROSSP: Compute the cross product of two vectors.

CV_COORD: Converts 2D and 3D coordinates between coordinate systems.

SCALE3: Sets up axis ranges and viewing angles for Direct Graphics 3D plots.

SCALE3D: Scales a Direct Graphics 3D unit cube into the viewing area.

SET_SHADING: Sets the light source shading parameters for Direct Graphics.

SURFR: Sets up 3D transformations for Direct Graphics.

T3D: Performs various Direct Graphics 3D transformations.

VERT_T3D: Transforms a Direct Graphics 3D array by a 4x4 transformation matrix.

Polygonal Mesh Routines

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COMPUTE_MESH_NORMALS: Computes normal vectors for a set of polygons.

MESH_CLIP: Clips a polygonal mesh to an arbitrary plane in space.

MESH_DECIMATE: Reduces the density of geometry while preserving as much of the original data as possible.

MESH_ISSOLID: Computes various mesh properties and determines if a mesh encloses space (is a solid).

MESH_MERGE: Merges two polygonal meshes.

MESH_NUMTRIANGLES: Computes the number of triangles in a polygonal mesh.

MESH_OBJ: Generates a polygon mesh for various simple objects.

MESH_SMOOTH: Performs spatial smoothing on a polygon mesh.

MESH_SURFACEAREA: Determines the surface area of a mesh, including integration of other mesh properties.

MESH_VALIDATE: Checks for NaN values in vertices, removes unused vertices, and combines close vertices.

MESH_VOLUME: Computes the volume that the mesh encloses.

POLYSHADE: Creates a Direct Graphics shaded surface representation from a set of polygons.

Surfaces and Contours

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CONTOUR: Draws a two-dimensional contour plot for a 2D array of data.

CONTOUR Procedure: Draws a Direct Graphics contour plot.

IMAGE_STATISTICS: Computes sample statistics for an N-dimensional array.

MIN_CURVE_SURF: Interpolates points with a minimum curvature surface or a thin-plate-spline surface.

POLAR_CONTOUR: Draws a Direct Graphics contour plot from polar-coordinate data in polar coordinates.

SHADE_SURF: Creates a Direct Graphics shaded-surface from gridded data.

SHADE_SURF_IRR: Creates a Direct Graphics shaded-surface from irregularly-gridded data.

SHOW3: Displays a Direct Graphics image, surface plot, and contour plot simultaneously.

SURFACE: Draws a 3D surface from 2D data or unstructured points.

SURFACE Procedure: Draws a Direct Graphics surface.

Tetrahedral Mesh Routines

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TETRA_CLIP: Clips a tetrahedral mesh to an arbitrary plane in space.

TETRA_SURFACE: Extracts a polygonal mesh as the exterior surface of a tetrahedral mesh.

TETRA_VOLUME: Computes properties of a tetrahedral mesh array.

Vector Field Visualization

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FLOW3: Draws Direct Graphics lines representing a 3D flow/velocity field.

INTERPOL: Performs linear interpolation on vectors.

PARTICLE_TRACE: Traces the path of a massless particle through a vector field.

STREAMLINE: Draws a streamline plot.

STREAMLINE Procedure = Draws a Direct Graphics streamline plot.

VECTOR: Draws a plot of either vectors or wind barbs.

VECTOR_FIELD: Places colored, oriented vectors of specified length at each vertex in an input vertex array.

VERT_T3D : Draws a Direct Graphics velocity (flow) field with streamlines.

Volume Visualization

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EXTRACT_SLICE: Returns 2D planar slice extracted from volume.

IDLgrVRML: Saves the contents of an Object Graphics hierarchy into a VRML 2.0 format file.

INTERVAL_VOLUME: Generates a tetrahedral mesh from volumetric data.

ISOSURFACE: Returns topologically consistent triangles by using oriented tetrahedral decomposition.

PROJECT_VOL: Returns a translucent rendering of a volume projected onto a plane.

QGRID3: Interpolates the dependent variable values to points in a regularly sampled volume.

QHULL: Constructs convex hulls, Delaunay triangulations, and Voronoi diagrams.

RECON3: Reconstructs a 3D representation of an object from 2D images.

SEARCH3D: Finds objects or regions of similar data values within a volume.

SHADE_VOLUME: Contours a volume to create a list of vertices and polygons.

SLICER3: Interactive Direct Graphics volume visualization tool.

VOXEL_PROJ: Generates a Direct Graphics volume visualization using voxel technique.

XOBJVIEW: Displays object viewer widget.

XOBJVIEW_ROTATE: Programmatically rotate an object.

XOBJVIEW_WRITE_IMAGE: Write the XOBJVIEW object to an image file.

XVOLUME: Direct Graphics utility for viewing and manipulating volumes and isosurfaces.