[jira] [Created] (SIS-384) (Affine → Passthrough → Affine) should be simplified as (Affine → Passthrough)

["Martin Desruisseaux (JIRA)" <ji...@apache.org>]

Martin Desruisseaux created SIS-384:
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             Summary: (Affine → Passthrough → Affine) should be simplified as (Affine → Passthrough)
                 Key: SIS-384
                 URL: https://issues.apache.org/jira/browse/SIS-384
             Project: Spatial Information Systems
          Issue Type: Improvement
          Components: Referencing
    Affects Versions: 0.8, 0.7, 0.6, 0.5
            Reporter: Martin Desruisseaux
            Priority: Minor
             Fix For: 1.0


Below is an example of concatenated math transform. An "Affine" operation appears twice: before and after the "Passthrough" operation:

{noformat}
Concat_MT[
  Param_MT["Affine",
    Parameter["num_row", 5],
    Parameter["num_col", 5],
    Parameter["elt_0_0", 0.025],
    Parameter["elt_0_4", 3.0125],
    Parameter["elt_1_1", -0.025],
    Parameter["elt_1_4", 44.9875]],
  PassThrough_MT[2, 1, Param_MT["Interpolation 1D",
      Parameter["values", {2.0, 10.0, 20.0, 35.0, 50.0, 75.0, 100.0, 150.0, 200.0, 250.0, 375.0, 500.0, 625.0, 750.0, 875.0, 1000.0, 1125.0, 1250.0, 1375.0, 1500.0, 1750.0, 2000.0, 2250.0, 2500.0, 2750.0, 3000.0}]]],
  Param_MT["Affine",
    Parameter["num_row", 5],
    Parameter["num_col", 5],
    Parameter["elt_3_3", 3600000.0],
    Parameter["elt_3_4", 1.5127128E12]]]
{noformat}

The last "Affine" operates only on passthrough coordinates. Consequently it could be moved before the "Passthrouh" operation, which would allow concatenation with the first "Affine" operation. It should not change the operation result, but can improve performance.



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