geotiff: forward max_pixels, window, band on GPU stripped fallback (#1732)

[brendancol]

Summary

• read_geotiff_gpu's stripped-TIFF fallback at xrspatial/geotiff/__init__.py:2533 called read_to_array(source, overview_level=overview_level) and threw away max_pixels, window, and band.
• Forward all three to read_to_array. The post-decode _gpu_apply_window_band is replaced with coord-only computation since the array is now pre-sliced.

Closes #1732.

Test plan

• New regression tests in test_gpu_stripped_forwarding_1732.py cover the max_pixels cap, windowed reads, band selection, and the window+band composition.
• Existing stripped-GPU tests still pass (test_gpu_stripped_multiband.py, test_orientation_gpu.py, predictor + nodata coverage).

[brendancol]

@copilot resolve the merge conflicts in this pull request

[Copilot]

@copilot resolve the merge conflicts in this pull request

Resolved in df44959. The only conflict was in xrspatial/geotiff/__init__.py: main renamed the import to _read_to_array, so I updated the stripped-fallback call to use that alias while keeping the forwarded window, band, and max_pixels arguments.

[Copilot]

Pull request overview

This PR fixes read_geotiff_gpu behavior for stripped (non-tiled) TIFFs so its CPU-fallback path honors the same max_pixels, window, and band arguments as the tiled GPU path, and adds regression tests for issue #1732.

Changes:

• Forward max_pixels, window, and band to read_to_array() in the stripped-TIFF GPU fallback.
• Replace post-decode _gpu_apply_window_band slicing in the stripped fallback with coord-only computation (since the array is now pre-sliced by read_to_array).
• Add new GPU regression tests covering max_pixels enforcement, windowed reads, band selection, and window+band composition.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
xrspatial/geotiff/__init__.py	Forward missing kwargs to read_to_array in stripped fallback and adjust coordinate generation accordingly.
xrspatial/geotiff/tests/test_gpu_stripped_forwarding_1732.py	New regression tests ensuring stripped fallback honors max_pixels, window, and band.

Comments suppressed due to low confidence (2)

xrspatial/geotiff/init.py:2531

• The comment says read_to_array only updates geo_info.transform for orientations 5–8, but read_to_array currently updates the transform for orientations 2–4 as well (when geo_info.has_georef is true). This is misleading for future maintainers; please update or remove the outdated note (and the reference to a sibling PR) so it matches the actual behavior.

          through to the next stage (CPU mmap re-decode for the first
          failure, full CPU decode + GPU transfer for the second). This
          preserves backward-compatible behaviour while making GPU
          regressions visible.
        - ``'strict'``: re-raise the original exception from either stage

xrspatial/geotiff/init.py:2578

• The windowed coord computation here checks t is None, but GeoInfo.transform is always a GeoTransform (even when has_georef=False), so this branch is effectively dead and non-georeferenced windowed reads will incorrectly compute float coords from the default identity transform. Consider keying off geo_info.has_georef (like _geo_to_coords) and returning integer pixel coords for non-georeferenced files, plus dropping the unreachable t is None branch.

        on_gpu_failure = gpu
    elif not new_passed:
        on_gpu_failure = 'auto'
    gpu = on_gpu_failure
    if gpu not in ('auto', 'strict'):
        raise ValueError(
            f"on_gpu_failure must be 'auto' or 'strict', got {gpu!r}")
    try:
        import cupy

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[brendancol]

Addressed in f087212: added explicit assertions on out.coords['y'], out.coords['x'], and out.attrs['transform'] so regressions in the coord-only path are caught.