Module vision_preprocess_glm 

2026-09-25: GLM image geometry: smart_resize to a canvas aligned to patch_size × spatial_merge_size, an aspect-preserving fit that never upscales, a black pad to the canvas, and the 2×2-block-major patch order. vision_preprocess uses it when VisionConfig::block_major_patches is set.

Owner: model-layers (vision input). Invariants: none beyond the types.

Functions

block_major_patch_index

2026-09-25: Index of the patch at (patch_row, patch_col) in the 2×2-block-major stream the GLM tower expects.

pixel_bounds

2026-09-25: (min_pixels, max_pixels) for smart_resize, as pixel areas.

resize_and_pad

2026-09-25: Fit img inside the smart_resize canvas preserving aspect, then zero-pad right/bottom to the canvas exactly. Returns the padded canvas.

smart_resize

2026-09-25: Snap each side to the nearest multiple of factor, then rescale by the area bounds if the snapped canvas violates them.