Glassvision/IfcOpenShell
1
0
Fork 0
mirror of https://github.com/IfcOpenShell/IfcOpenShell.git synced 2026-09-11 06:18:09 +00:00
Code Issues Packages Projects Releases Wiki Activity

wgpu: drop dormant spatial-bucket prototype

Browse Source 
Removed the WGPU_SPATIAL_BUCKETS=1 octree-style instance planner
(planSpatialChunks, SpatialPlan, the env-var pair, the field, the
load-time branch). Was an opt-in prototype kept in tree as a possible
acceleration for "find the right instance chunk", but:

- Benchmarked slower than mesh-keyed (~24-26 ms vs ~19.7 ms) — the
  higher chunk count's per-chunk bind-group + draw overhead more than
  ate the tight-AABB win on this dataset.
- Not load-bearing for the brace correctness fix — that turned out to
  be the AABB-projected screen-rect priority metric (commit 6200ab9fa),
  which works on either chunk topology.
- The "find the right chunk" hypothesis is moot: instance_chunk_idx[]
  is precomputed at load time, so cull has nothing to look up.

Git log preserves the implementation if it's ever revisited.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
This commit is contained in:
Dion Moult
2026-05-30 08:17:14 +10:00
parent 72af067c9a
commit d4169693c9
2 changed files with 4 additions and 187 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/ifcviewer-wgpu/WgpuViewportWindow.h
-27
View File
@@ -143,19 +143,6 @@ private:
float chunkScreenAreaPx(const WgpuModelGpuData::Chunk& c,
const QMatrix4x4& vp_mat) const;
// Octree-style spatial planner. Produces (a) per-bucket mesh_ids — a
// mesh may appear in multiple buckets if its instances scattered, and
// (b) per-instance bucket assignment. Each bucket carries its own
// mesh data in its chunk pool slice (duplicated when shared). Stop
// condition: bucket's union vertex bytes ≤ WGPU_CHUNK_VERTEX_BYTES_LIMIT
// and instance count ≤ spatial_max_instances_. See task #55.
struct SpatialPlan {
std::vector<std::vector<uint32_t>> chunk_mesh_ids;
std::vector<uint32_t> instance_to_chunk;
};
SpatialPlan planSpatialChunks(const std::vector<InstanceCpu>& instances,
const std::vector<MeshInfo>& meshes) const;
public:
// Queue a one-shot framebuffer capture: the next rendered frame is
@@ -536,20 +523,6 @@ private:
// and is per-model the right granularity?).
bool cull_threads_enabled_ = true;
// WGPU_SPATIAL_BUCKETS=1 swaps the streaming chunk planner from the
// mesh-keyed Morton+greedy algorithm to an octree-style spatial
// subdivision of INSTANCES. Same mesh may appear in multiple buckets
// (data duplicated) when its instances scatter — this is the central
// trade for tight per-chunk AABBs that actually match what cull and
// priority code want. See task #55.
bool spatial_buckets_enabled_ = false;
// Stop-subdividing thresholds for the octree planner. A cell becomes a
// leaf bucket when (a) the union vertex bytes of meshes its instances
// reference fits the chunk budget, AND (b) instance count is below the
// cap. Tunable via WGPU_SPATIAL_BUCKET_MAX_INSTS env var so we can
// sweep without rebuild during the prototype phase.
uint32_t spatial_max_instances_ = 5000;
public:
// Master switch for HiZ occlusion. OFF by default — has two issues vs
// the GL backend on this codepath (see task #58):