System Information

Definition Index

• ORG.SHIRAKUMO.FRAF.QUICKHULL

  No documentation provided.

  • EXTERNAL CONDITION

    EDGE-SOLVER-FAILED

    Source

    Warning signalled when the solver fails due to imprecision.
    
    See CONVEX-HULL

  • EXTERNAL FUNCTION

    CONVEX-HULL

    • VERTICES
    • &KEY
    • REDUCE-VERTICES
    • EPS

    Source

    Extract a convex hull mesh from the given set of vertices.
    
    VERTICES should be a sequence of FLOATs which describe the point cloud
    to extract a convex hull from. Each vertex should come in the form of
    consecutive X, Y, and Z coordinates. It is preferred that VERTICES be
    a (SIMPLE-ARRAY SINGLE-FLOAT (*)) or (SIMPLE-ARRAY DOUBLE-FLOAT (*)).
    
    If VERTICES only contains 2 or fewer vertices, an error is signalled.
    If VERTICES describes a point cloud that doesn't have any volume, an
    error is also signalled.
    
    Returns two values:
      1. A simple array of vertices that lie on the convex hull, in the
         same format as the input, including matching element-type.
      2. A (SIMPLE-ARRAY (UNSIGNED-BYTE 32)) of vertex indices, every
         triplet of which describes a triangle face on the hull. The
         vertex index must be multiplied by 3 in order to get the index of
         the first vertex in the returned vertices array.
    
    If a convex hull cannot be constructed exactly due to floating point
    imprecision, a warning of type EDGE-SOLVER-FAILED may be signalled. If
    EDGE-SOLVER-FAILED is signalled, the resulting convex hull may not be
    optimal.
    
    You may pass an optional EPS parameter (defaulting to 0.0001), which
    defines the minimal distance below which two vertices are considered
    the same and are merged together.
    
    You may pass an optional REDUCE-VERTICES parameter (defaulting to T),
    which if true causes the function to return a fresh array of vertices,
    only including those used in the convex hull. If NIL, the same vertex
    array that was passed in *may* be returned. A fresh array is
    nevertheless returned if the input vertices all lie in a single plane,
    thus requiring an extra vertex to form a hull with volume.
    
    See EDGE-SOLVER-FAILED