Windowed high-resolution mode kept one window over the union of displayed
columns. Two 512-wide buffers side by side need 18432 px at 18x, past a
16384 GPU limit, so the second buffer was refused and every other frame
presented at 1x.
- The window is now up to four tiles, each its own surface over a column
range. A new display first tries one surface over the union of all
displays (the old behaviour, so R4's 320-wide window is unchanged), then
a merge with the tiles it overlaps, then a tile of its own. Every
mirrored write (queued draws, fills, uploads, copies, the depth24 clear,
stencil rebuilds) goes to each tile it touches; present, captures,
screenshot_hires and the native-wide centre read the tile holding the
display. A display no tile can hold within the GPU limit, the memory
budget (all tiles together) or the tile cap still presents at 1x, logged.
- A copy into the window stages its S-scaled source in a scratch of its
own, in column chunks that fit the GPU limit, walked in memmove order so
an overlapping copy still reads pre-copy pixels. The shared scratch no
longer grows past the hr surface for it.
- Staging textures commit a new size only after the driver accepted the
storage; a size past the limit is refused with a log line and the
texture keeps its old storage (scratch_ensure used to record the size
before a glTexImage2D that could fail).
- PSX_GL_MAX_DIM lowers the GPU limit the backend plans with (testing a
layout for a smaller GPU). video_info adds display_x/display_y,
hires_window_tiles and hires_window_mib.
- gl_scale_invariance_test: side-by-side runs flip two 512-wide buffers
and require one surface at 5x and two tiles at 9x (PSX_GL_MAX_DIM=8192)
to equal the full-VRAM surface, including copies between the buffers
and 1000-column copies; at 18x both buffers must read back at S. A
scratch request past the limit must be refused and leave the texture
and its recorded size intact.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Shokunin
84dbc2982a