[computerguy526]

Related to the PRAGMATA bring-up, ccd834e (@seedds).

A 1D array (NVN target 3) is created as a one-row 2D array whose layer count is the NVN height (tex_desc). The upload paths took that same NVN height as each layer's row count. So every layer went up as height rows into a one-row slice. Metal's API validation refuses these copies (destinationOrigin.y + sourceSize.height must be <= height). Without validation the GPU writes past each slice, into the next layers.

Found on PRAGMATA: its light-profile lookup table is a 512-wide R16F 1D array of 64 layers, read by the deferred lighting. It went up as 64 copies of 64 rows. The junk rows made a light flash across a wall when the camera crossed a distance band. That was one of two causes of the flicker on my branch. The other was a host experiment of mine that main does not have. With both fixed, the flicker was gone by eye on the route where it showed (macOS 26, M4 Pro).

What changes

• tex_lh gives a level's row count as the Metal texture holds it: 1 for a 1D or 1D array texture, the NVN height otherwise.
• The upload paths use it: pkg_upload_'s byte count, its GPU deswizzle and CPU deswizzle loops, and the sparse texture's tile grid and tile uploads.
• Nothing else changes. 1D textures (target 0) already had height 1. Region-based operations on 1D arrays (WriteTexels, texture copies, clears) are not part of this PR.

Tests

• t_partial_upload gets two 1D array cases, R16F 1D array (512 x 64 layers, PRAGMATA's shape) and RGBA8 1D array with levels, with and without the direct (GPU) upload. Run under MTL_DEBUG_LAYER=1 as before. On main the first 1D array case aborts in validation: (destinationOrigin.y + sourceSize.height)(64) must be <= height(1). With the fix, all 4,551 checks pass.

Regression

• regress.py impact picks The Legend of Zelda: Breath of the Wild, Pokémon Scarlet and The Legend of Zelda: Tears of the Kingdom (the profiles with a usage manifest, through nvn_mtl.m). They were not run.
• Reach: only textures with NVN target 3 take another path. Every other target gets the same row count as before.