Replace 25 per-landblock VAOs with one shared buffer set. Vertex positions
are now baked in world space during AddLandblock (worldOrigin added to each
vertex), so uModel is eliminated from terrain.vert entirely. Buffer rebuild
happens on the cold path (landblock load/unload) via RebuildGpuBuffers.
Draw loop: bind VAO once, then one glDrawElements per visible landblock
into its sub-range of the shared EBO — same frustum-cull logic, no
VAO/VBO rebind overhead per landblock.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
1. Terrain culling: TerrainRenderer.Draw now accepts neverCullLandblockId,
matching StaticMeshRenderer. Both renderers skip frustum-culling the
player's current landblock. Previously only entities were exempt but
the terrain under the player still disappeared when looking away.
2. Yaw drift on Tab toggle: render loop stores rotation as Yaw - PI/2
(AC model facing offset), but yaw extraction on re-entering player
mode didn't compensate. Each Tab cycle rotated the player 90 degrees.
Now adds PI/2 back when extracting from the quaternion.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Per-landblock AABB culling against the view frustum. Each loaded
landblock has a 192×192 XY footprint + a Z range derived from the
terrain vertex min/max (padded +50 above / -10 below for entities
on top and basements). One AABB test per landblock per frame;
landblocks fully outside the frustum skip ALL their terrain draws
and entity draws (both opaque and translucent passes).
GpuWorldState gains SetLandblockAabb + LandblockEntries (per-landblock
iteration with AABB data). TerrainRenderer.Draw and
StaticMeshRenderer.Draw both accept an optional FrustumPlanes and
skip culled landblocks. GameWindow.OnRender extracts FrustumPlanes
from camera.View * camera.Projection and passes to both.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
TerrainRenderer's internal landblock collection is now a Dictionary
keyed by landblock id so the streaming system can release GPU
resources per-landblock as the visible window moves. AddLandblock
takes the id as its first parameter; if the same id is added twice,
the old buffers are freed before the new ones land (defensive but
cheap). RemoveLandblock is a no-op for unknown ids and deletes
VBO/EBO/VAO for known ones.
Single existing caller in GameWindow.cs updated to pass the id.
Build green. No unit tests — direct-to-GL methods need a live context.
Tasks 5-7 will validate end-to-end.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The visual-win commit that wires up the Phase 3c.1/.2/.3 building blocks:
Holtburg's terrain now uses AC's real per-cell texture-merge blend
(base + up to 3 terrain overlays + up to 2 road overlays, with alpha
masks from the alpha atlas) instead of the flat per-vertex single-layer
atlas lookup that preceded it.
Geometry rewrite:
- New TerrainVertex struct (40 bytes): Position(vec3) + Normal(vec3) +
Data0..3 (4x uint32 packed blend recipe)
- LandblockMesh.Build is now cell-based: iterates 8x8 cells instead of
the old 9x9 vertex grid, emits 6 vertices per cell (two triangles),
384 total vertices per landblock
- For each cell: extract 4-corner terrain/road values → GetPalCode →
BuildSurface (cached across landblocks via a shared surfaceCache) →
FillCellData → split direction from CalculateSplitDirection → emit
6 vertices in the exact gl_VertexID % 6 order WorldBuilder's vertex
shader expects
- Per-vertex normals preserved via Phase 3b central-difference
precomputation on the 9x9 heightmap, interpolated smoothly across
the cell (we deliberately didn't adopt WorldBuilder's dFdx/dFdy
flat-shade approach — Phase 3a/3b user-tuned lighting was worth
keeping)
Renderer rewrite:
- TerrainRenderer VAO: vec3 Position, vec3 Normal, 4x uvec4 byte
attributes for Data0..3. The uvec4-of-bytes read pattern matches
Landscape.vert so the ported shader math stays byte-for-byte
identical to WorldBuilder's.
- Binds both atlases: terrain atlas on unit 0 (uTerrain), alpha atlas
on unit 1 (uAlpha)
Shader rewrite (ports of WorldBuilder Landscape.vert/.frag, trimmed):
- terrain.vert: unpacks the 4 data bytes + rotation bits, derives the
cell corner from gl_VertexID % 6 + splitDir, rotates the cell-local
UV per overlay's rotation field, and computes world-space normal
for the fragment shader
- terrain.frag: maskBlend3 three-layer alpha-weighted composite for
terrain overlays, inverted-alpha road combine, final composite
base * (1-ovlA)*(1-rdA) + ovl * ovlA*(1-rdA) + road * rdA. Phase
3a/3b directional lighting applied on top (SUN_DIR, AMBIENT=0.25,
DIFFUSE=0.75, in sync with mesh.frag).
- Editor uniforms (grid, brush, unwalkable slopes) deliberately
omitted — not applicable to a game client
- Per-texture tiling factor hardcoded to 1.0 for now (WorldBuilder
reads it from uTexTiling[36] uploaded from the dats); one tile per
cell = 8 tiles per landblock-side, slightly coarser than the old
~2x-per-cell tiling. Tunable via the TILE constant if needed.
TerrainAtlas grew parallel TCode/RCode lists (CornerAlphaTCodes,
SideAlphaTCodes, RoadAlphaRCodes) so TerrainBlendingContext can be
built without the mesh loader touching the dats directly.
GameWindow builds a TerrainBlendingContext once, shares a Dictionary
<uint, SurfaceInfo> surfaceCache across all 9 landblocks. Output:
"terrain: 137 unique palette codes across 9 landblocks" — avg ~15
unique per landblock, cache reuse healthy.
LandblockMeshTests rewritten for 384-vertex layout. 77/77 tests green.
Visual smoke run launches clean: no shader compile/link errors, no
GL warnings, terrain renders to the screen.
User visual verification is the final acceptance gate for Phase 3c.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Introduce ICamera (View, Projection, Aspect) and make OrbitCamera implement
it. TerrainRenderer.Draw and StaticMeshRenderer.Draw now accept ICamera,
widening the call-site contract while leaving all runtime behavior unchanged.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds a 2-stage GLSL shader (vertex + fragment), a Shader helper that
compiles/links and exposes SetMatrix4 for uniforms, and an OrbitCamera
with yaw/pitch/distance and a 192-unit-centered target for a single
landblock. TerrainRenderer now takes a Shader and issues an actual
DrawElements call with uView + uProjection uniforms. GameWindow owns
the Shader and Camera, routes mouse drag to camera yaw/pitch, and
scroll wheel to camera distance.
The fragment shader maps world Z to a green-brown-white ramp so
lowlands read green, midlands brown, and peaks white — no textures
yet, but enough to visually confirm the terrain shape.
Shaders are copied to the output dir via a <None Update> item group.
Smoke verified against real dats: process stays alive with no GL
errors, no shader compile/link failures, and no exception trail.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
GameWindow now owns a DatCollection + TerrainRenderer. On load it
opens the dat directory passed as argv[0] (or ACDREAM_DAT_DIR), finds
Holtburg (landblock 0xA9B4FFFF) by default with a fallback to the
first landblock in the cell b-tree, builds the CPU mesh from
LandblockMesh.Build, and uploads VBO+EBO+VAO with a 3f/3f/2f attribute
layout. No draw call yet — shader and matrix uniforms land in Task 9.
Enabled AllowUnsafeBlocks on the App csproj so the fixed-buffer upload
in TerrainRenderer compiles. Uses dats.Get<LandBlock>(id) instead of
TryGet(..., out T) to sidestep the [MaybeNullWhen(false)] analysis that
TreatWarningsAsErrors was flagging.
Smoke verified against the real retail dats: prints
"loaded landblock 0xA9B4FFFF" and the window stays alive with no GL
errors or exceptions.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
