[I] allTouched/line rasterization can burn a corner-touched pixel at grid-aligned vertices (differs from GDAL by one pixel) [sedona]

["james-willis (via GitHub)" <gi...@apache.org>]

james-willis opened a new issue, #3120:
URL: https://github.com/apache/sedona/issues/3120

   ## Expected behavior
   
   `RS_AsRaster` with `allTouched = true`, and `LINESTRING` rasterization, aim to match GDAL (`rasterio.features.rasterize(all_touched=True)`) on which pixels are burned.
   
   ## Actual behavior
   
   After the exact-traversal fix (#3118), the two engines agree on all general input (a 100-case randomized fuzz over anisotropic grids matches GDAL exactly). They can still differ by a single pixel when a geometry vertex lands *exactly* on a grid line.
   
   Example on a 6x6 unit grid:
   
   ```sql
   SELECT RS_BandAsArray(RS_AsRaster(
     ST_GeomFromWKT('POLYGON ((1.5 1.5, 3.8 3.0, 4.5 4.4, 3.4 3.5, 1.5 1.5))'),
     RS_MakeEmptyRaster(1, 'B', 6, 6, 0.0, 6.0, 1.0, -1.0, 0.0, 0.0, 0),
     'B', true, 1.0, 0.0, false), 1);
   ```
   
   The vertex `(1.5 1.5)` sits exactly on a pixel corner. Sedona burns the corner-touched cell (the geometry does touch it, at that point); GDAL omits it.
   
   ## Notes
   
   This only occurs at exact grid-aligned vertices, never on general-position input, and it is a *superset* of GDAL — Sedona's result is consistent with the literal documented rule ("all pixels touched by the geometry"). GDAL's own behaviour at these degeneracies is not internally consistent (it includes some corner touches and omits others depending on edge direction), so there is no single reference to match. Filing for visibility; low priority and not currently planned.
   
   Discovered while fixing #3118.
   


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Re: [I] allTouched/line rasterization can burn a corner-touched pixel at grid-aligned vertices (differs from GDAL by one pixel) [sedona]

["jiayuasu (via GitHub)" <gi...@apache.org>]

jiayuasu closed issue #3120: allTouched/line rasterization can burn a corner-touched pixel at grid-aligned vertices (differs from GDAL by one pixel)
URL: https://github.com/apache/sedona/issues/3120


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