perf(render): keep solid meshes resident

Keep all solid geometry GPU-resident during navigation. Use vertex-rate instancing, compact untextured vertices, vertex-cache ordering, and cached silhouette sources without culling geometry.

src/scene/pipeline/device_capabilities.rs

@@ -20,10 +20,6 @@ impl DeviceCapabilities {
     /// instances, boundaries, families, dashes, and visibility.
     const HATCH_STORAGE_BINDINGS: u32 = 5;
 
-    /// Mesh compute culling reads one item buffer and writes four indirect
-    /// command buffers.
-    const MESH_CULL_BINDINGS: u32 = 5;
-
     pub fn detect(device: &wgpu::Device) -> Self {
         Self::from_limits(&device.limits())
     }
@@ -36,11 +32,6 @@ impl DeviceCapabilities {
         }
     }
 
-    /// Mesh instancing needs one read-only storage buffer.
-    pub fn supports_mesh_storage_instancing(self) -> bool {
-        self.max_storage_buffers_per_shader_stage >= 1
-    }
-
     pub fn supports_wire_storage(self) -> bool {
         self.max_storage_buffers_per_shader_stage >= Self::WIRE_STORAGE_BINDINGS
     }
@@ -49,10 +40,6 @@ impl DeviceCapabilities {
         self.max_storage_buffers_per_shader_stage >= Self::HATCH_STORAGE_BINDINGS
     }
 
-    /// WebGL2 reports zero storage bindings and stays on CPU mesh culling.
-    pub fn supports_mesh_compute_culling(self) -> bool {
-        self.max_storage_buffers_per_shader_stage >= Self::MESH_CULL_BINDINGS
-    }
 }
 
 #[cfg(test)]
@@ -63,19 +50,15 @@ mod tests {
     #[test]
     fn webgl_limits_select_compatibility_paths() {
         let caps = DeviceCapabilities::from_limits(&wgpu::Limits::downlevel_webgl2_defaults());
-        assert!(!caps.supports_mesh_storage_instancing());
         assert!(!caps.supports_wire_storage());
         assert!(!caps.supports_batched_hatch());
-        assert!(!caps.supports_mesh_compute_culling());
     }
 
     #[test]
     fn default_limits_select_storage_paths() {
         let caps = DeviceCapabilities::from_limits(&wgpu::Limits::default());
-        assert!(caps.supports_mesh_storage_instancing());
         assert!(caps.supports_wire_storage());
         assert!(caps.supports_batched_hatch());
-        assert!(caps.supports_mesh_compute_culling());
     }
 
     #[test]
@@ -86,8 +69,6 @@ mod tests {
             max_vertex_attributes: 16,
         };
         assert!(caps.supports_wire_storage());
-        assert!(caps.supports_mesh_storage_instancing());
         assert!(!caps.supports_batched_hatch());
-        assert!(!caps.supports_mesh_compute_culling());
     }
 }