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Parent: MorphoOptimizationProject
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=== Creating shape manipulation functions ===
See [[MorphoOptimizationProject_Manipulating_MRIS_et_al]]
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mris_fix_topology has a hot loop, which does unnecessary calculations of the face normals

mrisComputeOptimalRetessellation and mrisComputeRandomRetessellation have a similar structure

_:_: then it loops over a set of patches, or iterates on one patch. For each patch it calls

_:_:_: mrisDefectPatchFitness, which calls

_:_:_:_: mrisComputeDefectLogLikelihood, which calls

_:_:_:_:_: mrisComputeDefectMRILogUnlikelihood, which

_:_:_:_:_:_: does an expensive computation all the face normals for ALL the faces

_:_:_:_:_:_: does two other expensive steps, which only use a few of the face normals

To simplify, the original code does this

    loop

        for all fno normal[fno] = f (inputs)

        for a few fno use normal[fno]

        change some inputs

    end loop

    change some inputs

    use some normal[fno]

Since only a few of the face normals are used, it is a waste of time to calculate all of them every time around the loop!

This is replaced by code that does

    loop

        for all fno __normal[fno].deferred = true__

        for a few fno __if normal[fno].deferred normal[fno] = f (inputs); normal[fno].deferred = false__

        change some inputs

    end loop

    __for a few fno if normal[fno].deferred normal[fno] = f (inputs); normal[fno].deferred = false__

    change some inputs

    use some normal[fno]
See [[MorphoOptimizationProject_Deferring_calculations]]

Parent: MorphoOptimizationProject

A variety of techniques have been used.

Creating shape manipulation functions

See MorphoOptimizationProject_Manipulating_MRIS_et_al

Deferring calculations until needed

See MorphoOptimizationProject_Deferring_calculations

MorphoOptimizationProject_BetterSerialCode_DeferCalculations (last edited 2021-09-22 09:46:34 by DevaniCordero)