long *cxPyrActiveListNext( cxPyramid *pyr, long curLayer, long dstLayer, long count, long *list, long *numActive)
integer function cxPyrActiveListNext( pyr, curLayer, dstLayer, count, list, numActive )" integer pyr integer curLayer integer dstLayer integer count integer list(*) integer numActive
- Input pyramid structure for which computations are to be performed.
- Input layer of currently active elements (1-based value).
- Input layer of next active elements (1-based value).
- Input number of active elements in list at layer curLayer.
- Input array of active elements at layer curLayer.
- Output number of active elements in returned array at layer dstLayer.
cxPyrActiveListNext is useful in circumstances where a subset of the elements at a given level are to be manipulated, and the caller wishes to identify the subordinate elements to manipulate at a lower level. This is the approved way of determining the pyramid elements which should be manipulated or displayed in any pyramid-based module (the alternative method of displaying all elements available at a given level is not correct).
The returned index array is considered to be owned by the caller of cxPyrActiveListNext and should be freed (with free(3C)) after use.
Other routines exist to flag as active/inactive elements at a specified layer and to return a variable-length array of the active elements' indices, where curLayer is taken to be the pyramid top.cxPyramid(3E), cxPyrActiveList(3E), cxPyrActiveNext(3E), cxPyrActive(3E).
Last modified: Mon Nov 6 16:33:42 GMT 2000
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