Uploaded image for project: 'Spatial Information Systems'
  1. Spatial Information Systems
  2. SIS-384

(Affine → Passthrough → Affine) should be simplified as (Affine → Passthrough) or (Passthrough → Affine)

    XMLWordPrintableJSON

    Details

    • Type: Improvement
    • Status: Open
    • Priority: Minor
    • Resolution: Unresolved
    • Affects Version/s: 0.5, 0.6, 0.7, 0.8
    • Fix Version/s: 1.1
    • Component/s: Referencing
    • Labels:

      Description

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

      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}]]],
        Param_MT["Affine",
          Parameter["num_row", 5],
          Parameter["num_col", 5],
          Parameter["elt_3_3", 3600000.0],
          Parameter["elt_3_4", 1.5127128E12]]]
      

      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.

      This optimization is possible only for "Affine" that operate only on pass-through coordinates. If the last "Affine" does not comply with this condition, maybe the first "Affine" does. So we will need to test both.

        Attachments

          Issue Links

            Activity

              People

              • Assignee:
                Unassigned
                Reporter:
                desruisseaux Martin Desruisseaux
              • Votes:
                0 Vote for this issue
                Watchers:
                1 Start watching this issue

                Dates

                • Created:
                  Updated: