[FIocker]

This adds a Shadow resolution row to the Graphics tab: Game, 1.5x, 2x, 3x or 4x. It is saved as shadow_resolution, applies after a restart, and sits under Detail, outside the Quality preset. The default is Game, so nobody's picture changes until they opt in. It's a standalone PR on main (rebuilt on 51da046).

Why

OoT's shadow maps are fairly coarse on a big monitor. The characters' maps are 768 px or smaller. The sun's three cascades are only 1600 × 1600 (D16, docked), and each farther cascade spreads those pixels over more ground. Shadows lose detail with distance, and edges show stair steps and shimmer.

How

Everything happens in the renderer; the game isn't patched.

• Which textures, and how big (gpu/vk/shadow_res.h, pure, no Vulkan): the predicate, the side and the edge rounding, used by create, scissor_rect and vk_xfer.cpp.
• Bigger images (vk_texture.cpp, create): textures that look like shadow maps get a larger VkImage. That means square depth textures, 2D or 2D array, one level, single sample, 256 to 4096 px and a multiple of 32. The multiple of 32 leaves out the odd sizes that follow dynamic resolution. Each side is capped at 8192 px and each image at 1 GB. Texture::rs stores the scale, and the VRAM budget counts the larger image. VRAM compaction (RX_VK_COMPACT=1) rebuilds a moved image at its image size, so a scaled map stays scaled. width and height stay at the game's size, so uploads, buffer copies and read-backs still address the game's texels, inside the image.
• Passes scaled to match (vk_draw.cpp): targets() sizes a depth-only pass over such a texture to its image and sets Targets::scale. The game's viewport, scissor and clear rectangles are multiplied by that scale. The draw's scissor and both clears use scissor_rect, which rounds each edge to the nearest texel (shadow_res::edge), so rectangles that meet still meet. At Game it gives the same rectangles as before.
• Depth bias: the existing character (≤ 768) and cascade (> 768) checks compare against the game's size, not the scaled one. The game's slope-scaled factor is multiplied by the scale: it is per pixel of depth slope, and a k-times-larger map has 1/k the slope per pixel. So the bias stays what the game asked for, and acne doesn't come back at higher settings.
• Transfers (vk_xfer.cpp):
  • Region clears and texture-to-texture copies on a scaled map are scaled too.
  • A copy between differently scaled sides is a blit, where the depth format supports one; otherwise it's skipped with a warning.
  • A buffer copy of a scaled map gets only its top-left corner, the game's size of it, with a warning (copy_b2t). OoT never copies its shadow maps to buffers, but this is why the option is shaped around how OoT uses its maps, not a general texture scale.
• Sampling needs no change. The game reads shadow maps with normalized coordinates, so it gets the finer map as is.

A depth texture that qualifies but is drawn alongside colour targets isn't a shadow map. That pass keeps the game's size, and the texture's size and format go on a refusal list (shadow_res_refuse), so the texture is made at the game's size when the game makes it again. The texture already made keeps its larger image, so anything sampling that depth would read the wrong region until then. It's a logged limitation: OoT's shadow passes are depth-only, and it hasn't happened.

Cost

The cascades take about 15 MB at the game's size, 61 MB at 2x (3200² × 3) and 246 MB at 4x (6400² × 3). The characters' maps cost little at any setting.

Testing

• Builds: on this branch, vk_draw.cpp, vk_texture.cpp, vk_xfer.cpp and vk_menu.cpp compile with clang using nx2/build.py's renderer flags. The full game builds with MSVC as part of the combined build, which has the same change. llvm-mingw and Linux need CI.
• Tests: tests/run_all.py, the whole suite, locally (clang targeting MSVC, the CPM Vulkan headers, glslang 11.12): 433 passed. The failures are exactly the ones main at 51da046 has on the same machine, all down to the local toolchain. Of these:
  • tests/test_shadow_resolution.py checks the predicate on OoT's sizes and the odd ones, and the 8192 and 1 GB caps. It also checks that every qualifying size at every factor maps the game's whole extent onto the whole image, and that edges stay in order and shared, so rectangles that meet still meet (1.5x included).
  • test_preset_exempt, test_menu_restart_slots and test_native_astc_texture_count pass too.
• In game: played at 4x on an NVIDIA RTX card. The sun's cascades were enlarged from 1600 to 6400 and the characters' maps from 768 to 3072. Far shadows keep their detail, and the drop-off with distance is gone. Still to come: Game and 1.5x on this head, and a Game vs 4x screenshot pair of the same far shadow.

🤖 Generated with Claude Code

[ghost]

Thanks, this is a nice, self-contained way to do it: width/height stay the game's and only the image and the passes over it grow, so uploads, copies and sampling mostly don't need to know. I went through targets(), the viewport/scissor/clear scaling, the bias checks, copy_t2t/clear_tex, and the image/budget sizing. At Game (factor 1) scissor_rect gives the same rectangles as the old dynamic-state scissor and clear_rect, so the refactor shouldn't change anything when the option is off.

Blockers:

• Conflicts with main. The branch is 191 commits behind. vk_menu.cpp and vk_menu.h conflict with the new Anisotropic filtering row and opts.anisotropy. Both are trivial to fix (keep both). The other four files merge cleanly. Because of the conflict, no CI has run on this PR, so nothing has built it with llvm-mingw or on Linux yet (the description only mentions MSVC, which the project doesn't ship with). Please rebase so the checks run. After the merge there are 12 restart rows against kMax = 16, so test_menu_restart_slots still passes.

Worth fixing (inline):

• The game's slope-scaled depth bias isn't scaled with the map. Details on the gw line.
• Main's VRAM compaction (RX_VK_COMPACT=1, off by default) rebuilds images at t->width/t->height. It would shrink a scaled shadow map back to the game's size while rs stays above 1. Details on the ci.extent line.

Smaller things:

• A texture refused in targets() (depth drawn with colour) keeps its larger image until the game makes it again. If something samples that depth, it reads the wrong region, because only the game-sized top-left corner was drawn. That's fine as a logged limitation for OoT, whose shadow passes are depth-only. Maybe say so in the comment, since the refusal only applies to the next texture made.
• Nit: clear_rect is now just a forwarder to scissor_rect. Its two callers could call scissor_rect directly.
• Testing: only 4x has been played. A short run at Game and at 1.5x would be good, since 1.5x gives non-integer edges (768 -> 1152) and is the setting most likely to show seams from the rounding. A source test for the qualifying predicate and the scissor_rect rounding (two rectangles that meet still meet) would also fit the repo's style.

No other reviews or comments on the PR yet. Once it's rebased and CI is green, I'd be happy to look again.

[ghost]

The constant bias checks use the game's size now, good. But the game's own slope-scaled bias (d.bias[2] = s.poly_offset[0] a few lines up) is in units of the depth slope per pixel. At scale k, each pixel covers 1/k as much ground, so the slope term drops by k. At 4x the cascades get a quarter of the slope bias the game asked for, which is the usual way acne comes back at higher shadow resolutions. Something like if (at.scale != 1.0f) d.bias[2] *= at.scale; (for depth-only passes) would keep the game's bias. It didn't show on your RTX run, but it's cheap to keep equal, and other GPUs' rasterizers differ.

[ghost]

Once this is merged with main: compact_step (VRAM compaction, RX_VK_COMPACT=1, off by default) rebuilds a moved image "as create() made it" with ci.extent = {t->width, t->height, t->depth} and copies t->width >> l per level. For a scaled shadow map that makes a game-sized image while rs stays above 1. The next pass then gets a render area and viewport of image_width(tex), past the image's extent, which is a validation error or a GPU fault. It only applies to textures not created as targets and with compaction on, but it's a one-line fix: use image_width(t)/image_height(t) there and in the copy regions.

[ghost]

Nit: clear_rect only forwards now. The two callers could call scissor_rect directly.

[FIocker]

Thanks for going through it this closely. All points are addressed: the branch is rebased on main (d7a7306), the menu conflicts are resolved by keeping both rows, and the fixes are in fda8a1c.

• Slope bias: good catch. if (at.scale != 1.0f) d.bias[2] *= at.scale; sits right after the game's bias is read. Only a depth-only pass over a scaled map has a scale, so nothing else changes.
• Compaction: compact_step now makes the image at image_width(t) / image_height(t), and its copy regions use them too.
• Refusal comment: it now says the texture already made keeps its larger image, so a sampler would read the wrong region until the game makes the texture again. It's logged, and OoT's shadow passes are depth-only.
• clear_rect: removed. The two clears call scissor_rect directly.
• Source test: the predicate, the side and the edge rounding moved to gpu/vk/shadow_res.h, with no Vulkan. create, scissor_rect and vk_xfer.cpp all use it. The new tests/test_shadow_resolution.py compiles the header and checks:
  • OoT's sizes are taken; the odd dynamic sizes, small, non-square, multi-level, multisampled and sparse ones are not.
  • The 8192 and 1 GB caps hold.
  • For all 121 qualifying sizes at 1.5x, 2x, 3x and 4x, the game's whole extent maps onto the whole image through both edge() and image_size().
  • Every game edge moves forward, and rectangles that meet still meet. That covers 1.5x's non-integer edges, e.g. 768 → 1152.
  • The callers really use it.
• Builds: the four changed renderer files compile on this branch with clang and nx2/build.py's renderer flags (syntax-only). The C++ fixture builds with clang targeting MSVC. CI still waits for approval to run llvm-mingw and Linux.
• Game and 1.5x: not played yet. That needs a real run, and I'll post results.

[FIocker]

Follow-up in cdb8791: test_vulkan_clear_mip's stand-in Texture gets rs and the shadow_res.h helpers that clear_tex now uses; without them the fixture didn't compile. I've now run the whole tests/run_all.py on this branch locally (clang targeting MSVC, the CPM Vulkan headers, glslang 11.12). It gives the same results as main at d7a7306 on the same machine: 325 passed, and the 18 failures are the same 18 main has here, all down to this PC's toolchain.

[ghost]

Heads-up: this conflicts with main now. Could you rebase onto main and resolve the conflicts? Thanks!

[Joey-Magnus]

The follow-ups to hckrman101's review look right to me: the slope-bias scale in vk_draw.cpp, compact_step building at image_width/image_height, and shadow_res.h with its test. A few things are left before this can be judged. The title isn't a conventional commit, so the only check that ran fails; something like "feat(vk): shadow resolution option" would pass. The branch conflicts with main again in vk_menu.cpp and vk_texture.cpp, so llvm-mingw and Linux have still never built it. The description has no screenshots, and this changes what's on screen; a Game vs 4x pair of the same far shadow would do. Game and 1.5x are still unplayed, and 1.5x is where the non-integer edges are. Also worth saying in the description: a buffer copy of a scaled map only gets its top-left corner (the warn in copy_b2t), so the option is shaped around how OoT uses its maps. The default stays Game, so nobody's picture changes until they opt in.

[FIocker]

Rebuilt on main at 51da046 (5e94a6a), and the title is now a Conventional Commit. Changes from the rebase:

• The row sits under main's new Detail section, and it's preset_exempt; test_preset_exempt caught that it should be.
• The VRAM budget counts the larger image, without touching texture_level_units' line, which test_native_astc_texture_count pins.
• The description now says what Joey asked for: the default stays Game, and a buffer copy of a scaled map gets only its top-left corner. It says the option is shaped around how OoT uses its maps.

The whole local run_all.py matches main: 433 passed, and the failures are main's own on this machine. Still to come: Game and 1.5x on this head, and a Game vs 4x screenshot pair.

[Joey-Magnus]

The title, the rebase and the description are done. 5e94a6a merges cleanly with current main, and CI is green, llvm-mingw and the AppImage included. I also read the row's placement under Detail (it's preset_exempt) and the budget change in create(). At Game, shadow_resolution_factor() is 1 and qualifies() is never reached, so nobody's picture changes.

Two things from my last review are still open, as the description says:

• There are no screenshots yet. This changes what's on screen, and CONTRIBUTING asks for them. A Game vs 4x pair of the same far shadow would do.
• Game and 1.5x haven't been played on this head. 1.5x is where shadow_res::edge rounds to non-integer texels (768 to 1152), so it's the setting most likely to show seams, even though test_shadow_resolution checks that the edges meet.

Once those are posted, I'd be glad to see this go in.