Fixes #906: fill remaining dask+cupy gaps (terrain, perlin, crosstab)#913
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brendancol merged 4 commits intomasterfrom Feb 27, 2026
Merged
Fixes #906: fill remaining dask+cupy gaps (terrain, perlin, crosstab)#913brendancol merged 4 commits intomasterfrom
brendancol merged 4 commits intomasterfrom
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Add missing dask+cupy backends for perlin() and generate_terrain() using per-chunk GPU kernel launches via da.map_blocks with block_info coordinate mapping. Add cupy and dask+cupy backends for crosstab() by converting to numpy/dask+numpy and delegating. Fix _find_cats() to handle pure cupy arrays without wrapping in @delayed.
- Terrain Generation, Perlin Noise: mark dask+cupy as ✅ (native) - Zonal Cross Tabulate: mark cupy and dask+cupy as 🔄 (CPU fallback) - Zonal Statistics: mark cupy as ✅ (native), dask+cupy as 🔄 (fallback) - Apply: mark cupy and dask+cupy as 🔄 (CPU fallback)
Both functions only need numpy for the boundary scan; the output is a slice of the original DataArray, so the backend is preserved. Convert to numpy for the scan, then slice the original raster. Update README feature matrix for trim and crop.
JIT-compile the user's scalar function as a CUDA device function and run it inside a CUDA kernel, avoiding the GPU→CPU→GPU round-trip. Non-compilable functions (e.g. using dict, str) automatically fall back to the existing CPU path via exception handling.
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Summary
perlin()— launches_perlin_gpukernel per chunk with coordinate ranges computed fromblock_infogenerate_terrain()— same per-chunk GPU kernel approach across 16 noise layerscrosstab()— converts to numpy/dask+numpy and delegates (output is a DataFrame, no GPU advantage in aggregation)_find_cats()to handle pure cupy arrays without wrapping in@delayedCloses #906
Test plan
test_dask_cupy_gaps.py: perlin dask+cupy, terrain dask+cupy, crosstab cupy, crosstab dask+cupy