Implements GlGpuDevice and the rest of AcDream.App.Rendering.Gpu.Gl,
filling the V0-pinned IGpuDevice contract on OpenGL 4.3. This is the
first of the port slices described in
docs/plans/2026-07-27-vulkan-campaign.md: every later renderer port
(V2 onward) needs a real, driver-proven GL implementation of the RHI
to port onto, and the GL backend is deliberately built to be
behaviour-preserving rather than optimal, because that is what turns
each subsequent slice's pixel gate into a strict identity check
instead of a moving target. The Vulkan backend (V5+) is where the
actual efficiency gains land.
GlGpuDevice is a fresh root, not derived from Chorizite's
BaseGraphicsDevice/OpenGLGraphicsDevice - shedding that inheritance is
one of the things this campaign explicitly does. It owns its own
BindlessSupport instance rather than sharing the legacy WB render
path's, which is what lets it be constructed the moment a GL context
and a GpuFrameFlightController exist, with no dependency on when
WorldRenderCompositionPhase happens to detect bindless support later
in startup. The ring buffer keeps a managed staging array plus a real
GL buffer per flight slot and flushes with one BufferSubData
immediately before each Draw/DrawIndexed/MultiDrawIndexedIndirect
(never at bind time, since a renderer may still write after binding);
V1 throws on an over-capacity ring request rather than growing it,
since nothing consumes the device yet and a silent grow would hide a
future renderer's real working set. The texture table is a bump/free-
list allocator over a managed uvec2 handle array, gated through the
frame-flight retirement queue so a released slot cannot be reused
while a submitted frame might still read it. Push constants are
applied by uniform name on the currently-bound program, cached per
program, and explicitly re-applied whenever BindPipeline switches
programs - GL uniforms are per-program state, so the "survives
pipeline changes within a pass" guarantee the interface documents (a
freebie on Vulkan's shared pipeline layout) has to be emulated here.
BindlessSupport gained one additive method,
GetResidentHandle(texture, sampler), calling the same
ArbBindlessTexture.GetTextureSamplerHandle entry point
ManagedGLTextureArray already uses through a different path. The
existing GetResidentHandle(texture) cannot express
IGpuDevice.RegisterTexture's documented pair semantics ("the same
texture registered with two samplers occupies two slots"), so this
was the minimal change needed rather than a workaround.
The pure bookkeeping - ring watermark/alignment arithmetic, the
texture-slot allocator, render-state diffing, the push-constant field-
to-uniform-name table, and GL format mapping - lives in small GL-free
classes so it is unit-testable without a live context, following the
same seam pattern GpuFrameFlightController already uses for its fence
API. GlGpuTimerPool follows suit with an injectable timer-query API.
The device is constructed in HostInputCameraCompositionPhase
immediately after the frame-flight controller (the same phase that
already builds GpuFrameFlightController), rather than in
WorldRenderCompositionPhase as first considered: GlGpuDevice's self-
contained bindless detection means it has no ordering dependency on
the legacy WB path's BindlessSupport, so it can be proven against the
real driver as early as possible while keeping the composition change
to one phase. Composition, publication, and shutdown wiring follow
the existing acquire/publish/fault-injection pattern exactly, and GPU
device disposal is scheduled through the frame-flight retirement queue
before that queue itself is torn down. Nothing consumes the device
yet - that starts at V4a - so this slice's pixel gate is trivially a
tripwire.
App tests: 3834 passed / 3 skipped (V0 baseline 3785 + 49 new: ring,
texture-slot, render-state, push-constant, format-mapping, enum-
mapping, and timer-pool tests, plus one new fault-injection point in
the existing composition theory).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Give terrain, sky, retained UI, portal preparation, and the update/render frame pair explicit single owners. Make shader, texture, text, bindless, and GL construction prefixes checked and retryable so partial failure cannot lose or replay resource ownership.
Co-authored-by: Codex <codex@openai.com>
Symptom: terrain renders pure black in modern path (legacy renderer
correct). Diagnostic at TerrainModernRenderer.Draw showed:
glProgramUniformHandle(prog=4, loc=5, handle=0x100251xxx) → GL_INVALID_OPERATION (0x0502)
on both terrain and alpha sampler uniforms.
Root cause: the `uniform sampler2DArray` + glProgramUniformHandleARB
combination is rejected by the NVIDIA Windows driver in this configuration.
The handle is valid and resident; the uniform location is valid; the
program is valid; but the driver refuses to bind a 64-bit handle to a
sampler uniform via the program-uniform path.
Fix: switch to N.5's mesh_modern pattern — pass each 64-bit handle as a
`uniform uvec2` (low + high 32-bit halves) and construct the sampler at
the use site via the GLSL `sampler2DArray(handle)` constructor. This
form is what ARB_bindless_texture documents as universally supported and
is what N.5 already uses successfully.
Files:
- terrain_modern.frag: replace `uniform sampler2DArray uTerrain/uAlpha`
with `uniform uvec2 uTerrainHandle/uAlphaHandle` + `#define`s
- TerrainModernRenderer.cs: cache uvec2 uniform locations; set via
`glProgramUniform2(program, loc, low32, high32)` per frame
- BindlessSupport.cs: remove now-unused `SetSamplerHandleUniform`,
leave a comment noting why the helper was retired
- GameWindow.cs: also strip the temporary [TERRAIN-DBG] cursor-wrap
print added during the perf-baseline investigation
Build green; 114/114 tests in N.5+N.5b filter still pass; user-verified
terrain renders correctly in modern path post-fix. Captured fresh perf
baseline:
- Legacy: cpu_us median 1.5 / p95 3.0 (1 chunk = 1 glDrawElements)
- Modern: cpu_us median 6.4-7.0 / p95 9-14 (51 visible LBs, 1 MDI call)
Modern is ~4× slower on CPU at radius=5 because the chunked legacy path
already collapsed the scene to one draw call. The architectural wins
(zero glBindTexture/frame; constant-cost dispatch as A.5 raises radius)
will be documented in T10's perf baseline doc; the spec's
"≥10% lower CPU" acceptance criterion is invalid at radius=5 and needs
revision.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The new terrain dispatcher. Single global VBO/EBO with a slot
allocator (one slot per landblock, 384 verts × 40 bytes per slot).
Per-frame: build DEIC array from visible slots, upload, dispatch
via glMultiDrawElementsIndirect. Atlas textures bound via bindless
handles set per-frame as sampler uniforms.
Total ~6-8 GL calls per frame for terrain regardless of visible
landblock count (vs today's per-LB binds at radius=2 → ~25 calls,
radius=5 → ~121 calls).
API mirrors TerrainChunkRenderer so GameWindow integration in T8 is
a drop-in field+ctor swap.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Code quality review caught:
- Silent failure when ARB_bindless_texture absent — the && short-circuit
meant the most common fallback case (no bindless on the GPU) had no
log, while ARB_shader_draw_parameters absent did log. Restructured to
three nested ifs so each failure path logs symmetrically.
- Redundant `bindless is not null` guard removed (TryCreate's non-null
guarantee covers it; the nested-if structure makes this implicit).
- HasShaderDrawParameters in BindlessSupport.cs replaced its manual
GL_NUM_EXTENSIONS scan with `gl.IsExtensionPresent(...)` — same
pattern WB uses, less code.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Code quality review caught three related issues:
- _gl field stored but never used (TreatWarningsAsErrors=true would
catch this on a clean build, but better to fix it before it bites)
- GL constructor parameter became unused after dropping _gl
- IsAvailable => true is misleading: TryCreate's out parameter is
the canonical signal, the property carries no information
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds Silk.NET.OpenGL.Extensions.ARB 2.23.0 package and a thin
BindlessSupport wrapper exposing GetResidentHandle / MakeNonResident /
HasShaderDrawParameters. TryCreate returns false if the bindless
extension isn't present, letting WbFoundationFlag fall back to legacy.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>