Implement blender scene export script, add support for asset based level geom instancing

.envrc

@@ -0,0 +1 @@
+layout python3

.gitignore

@@ -19,3 +19,4 @@ game_web/
 .venv
 build/
 bin/
+.direnv/

.tool-versions

@@ -0,0 +1 @@
+python 3.11.13

assets/blender/test_level_blend/Scene.scn

@@ -0,0 +1,50 @@
+(inst
+	:model "assets/blender/testblend_blend/Bakery.glb"
+	:pos (0.000000 12.000000 0.000000) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (1.000000 1.000000 1.000000))
+(inst
+	:model "assets/blender/test_level_blend/Plane.glb"
+	:pos (0.000000 0.000000 0.000000) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (22.469545 22.469545 22.469545))
+(inst
+	:model "assets/blender/testblend_blend/Fire_Station.glb"
+	:pos (9.000000 13.000000 0.000000) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (1.000000 1.000000 1.000000))
+(inst
+	:model "assets/blender/testblend_blend/Gas_Station_Shop.glb"
+	:pos (-8.000000 11.000000 0.000000) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (1.000000 1.000000 1.000000))
+(inst
+	:model "assets/blender/testblend_blend/Gas_Station_Shop.glb"
+	:pos (-16.000000 11.000000 0.000000) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (1.000000 1.000000 1.000000))
+(inst
+	:model "assets/blender/testblend_blend/Gas_Station_Shop.glb"
+	:pos (-15.559284 0.259853 1.609015) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (1.000000 1.000000 1.000000))
+(inst
+	:model "assets/blender/testblend_blend/Green_House.glb"
+	:pos (14.000000 -7.000000 0.000000) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (1.000000 1.000000 1.000000))
+(inst
+	:model "assets/blender/testblend_blend/Hotel.glb"
+	:pos (8.000000 -18.000000 0.000000) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (1.000000 1.000000 1.000000))
+(inst
+	:model "assets/blender/test_level_blend/NurbsPath.glb"
+	:pos (0.000000 0.000000 0.000000) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (1.000000 1.000000 1.000000))
+(inst
+	:model "assets/blender/ice_cream_truck_blend/Split.glb"
+	:pos (-1.000000 3.000000 0.000000) 
+	:rot (0.000000 0.000000 0.000000 1.000000) 
+	:scale (1.000000 1.000000 1.000000))

blender/batch_export.py

@@ -0,0 +1,87 @@
+import bpy
+import os
+import pathlib
+
+# Ensure blend file is saved
+blend_filepath = bpy.data.filepath
+if not blend_filepath:
+    raise Exception("Blend file is not saved")
+
+assert bpy.context.scene is not None
+
+def clean_blend_path(blend_path: str) -> str:
+    return os.path.join(os.path.dirname(blend_path), bpy.path.clean_name(os.path.basename(blend_path)))
+
+# Directory setup
+abs_filepath = bpy.path.abspath(blend_filepath)
+src_assets_path = os.path.dirname(abs_filepath)
+project_path = os.path.dirname(src_assets_path)
+assets_path = os.path.join(project_path, "assets")
+rel_blend_path = os.path.relpath(abs_filepath, src_assets_path)
+clean_rel_path = clean_blend_path(rel_blend_path)
+scene_name = bpy.context.scene.name
+instance_output_path = os.path.join(assets_path, "blender", clean_rel_path, f"{scene_name}.scn")
+
+# Utility: returns path to store the glb
+def get_model_export_path(obj: bpy.types.Object) -> str:
+    if obj.instance_type == 'COLLECTION' and obj.instance_collection:
+        lib_path = obj.instance_collection.library.filepath
+        collection_name = bpy.path.clean_name(obj.instance_collection.name)
+        rel_lib_path = os.path.relpath(bpy.path.abspath(lib_path), src_assets_path)
+        rel_lib_path = clean_blend_path(rel_lib_path)
+        return os.path.join("blender", rel_lib_path, f"{collection_name}.glb")
+    else:
+        obj_name = bpy.path.clean_name(obj.name)
+        return os.path.join("blender", clean_rel_path, f"{obj_name}.glb")
+
+# Utility: writes an object to glb
+def export_object_as_glb(obj: bpy.types.Object, export_path: str):
+    full_export_path = os.path.join(assets_path, export_path)
+    pathlib.Path(os.path.dirname(full_export_path)).mkdir(parents=True, exist_ok=True)
+
+    bpy.ops.object.select_all(action='DESELECT')
+    obj.select_set(True)
+
+    assert bpy.context.view_layer is not None
+    bpy.context.view_layer.objects.active = obj
+
+    bpy.ops.export_scene.gltf(filepath=full_export_path, use_selection=True, export_apply=True)
+    print(f"Exported {obj.name} -> {export_path}")
+
+# Collect all visible, non-hidden objects in the scene
+visible_objects = [
+    obj for obj in bpy.context.scene.objects
+    if obj.visible_get()
+]
+
+exported = set()
+instances = []
+
+for obj in visible_objects:
+    model_path = get_model_export_path(obj)
+
+    if model_path not in exported:
+        export_object_as_glb(obj, model_path)
+        exported.add(model_path)
+
+    loc = obj.location
+    rot = obj.rotation_quaternion
+    scale = obj.scale
+    instance_sexpr = (
+        '(inst'
+        f'\n\t:model "assets/{model_path}"'
+        f'\n\t:pos ({loc.x:.6f} {loc.y:.6f} {loc.z:.6f}) '
+        f'\n\t:rot ({rot.x:.6f} {rot.y:.6f} {rot.z:.6f} {rot.w:.6f}) '
+        f'\n\t:scale ({scale.x:.6f} {scale.y:.6f} {scale.z:.6f}))'
+    )
+    instances.append(instance_sexpr)
+
+# Save instances to scene file
+instance_output_abs = os.path.join(project_path, instance_output_path)
+pathlib.Path(os.path.dirname(instance_output_abs)).mkdir(parents=True, exist_ok=True)
+
+with open(instance_output_abs, "w", encoding="utf-8") as f:
+    for line in instances:
+        f.write(line + "\n")
+
+print(f"Written instances to {instance_output_abs}")

game/assets/assets.odin

@@ -15,12 +15,25 @@ import "libs:tracy"
 
 _ :: math
 
+@(private = "file")
+g_assetman_instance: ^Asset_Manager
+
+init :: proc(assetman: ^Asset_Manager) {
+	g_assetman_instance = assetman
+}
+
+manager :: #force_inline proc() -> ^Asset_Manager {
+	return g_assetman_instance
+}
+
 Loaded_BVH :: struct {
 	// AABB of all bvhs
-	aabb:    bvh.AABB,
+	aabb:     bvh.AABB,
 	// BVH for each mesh in a model
-	bvhs:    []bvh.BVH,
-	modtime: physfs.sint64,
+	bvh:      bvh.BVH,
+	vertices: []rl.Vector3,
+	indices:  []u16,
+	modtime:  physfs.sint64,
 }
 
 Loaded_Convex :: struct {
@@ -34,13 +47,12 @@ Loaded_Curve_2D :: struct {
 	points: [][2]f32,
 }
 
-destroy_loaded_bvh :: proc(loaded_bvh: Loaded_BVH) {
+destroy_loaded_bvh :: proc(loaded_bvh: ^Loaded_BVH) {
 	tracy.Zone()
 
-	for &mesh_bvh in loaded_bvh.bvhs {
-		bvh.destroy_bvh(&mesh_bvh)
-	}
-	delete(loaded_bvh.bvhs)
+	bvh.destroy_bvh(&loaded_bvh.bvh)
+	delete(loaded_bvh.vertices)
+	delete(loaded_bvh.indices)
 }
 
 Curve_2D :: [][2]f32
@@ -361,7 +373,7 @@ get_music :: proc(assetman: ^Asset_Manager, path: cstring) -> rl.Music {
 
 null_bvhs: []bvh.BVH
 
-get_bvh :: proc(assetman: ^Asset_Manager, path: cstring) -> Loaded_BVH {
+get_bvh :: proc(assetman: ^Asset_Manager, path: cstring) -> (Loaded_BVH, bool) {
 	tracy.Zone()
 
 	loaded_bvh, ok := assetman.bvhs[path]
@@ -370,43 +382,57 @@ get_bvh :: proc(assetman: ^Asset_Manager, path: cstring) -> Loaded_BVH {
 	should_recreate := reloaded || !ok
 
 	if ok && should_recreate {
-		destroy_loaded_bvh(loaded_bvh)
+		destroy_loaded_bvh(&loaded_bvh)
 		delete_key(&assetman.bvhs, path)
 	}
 
 	if should_recreate {
-		new_bvhs := make([]bvh.BVH, model.meshCount)
-
-		outer_aabb := bvh.AABB {
-			min = max(f32),
-			max = min(f32),
-		}
+		vert_count := 0
+		indices_count := 0
 
 		for i in 0 ..< model.meshCount {
 			mesh := model.meshes[i]
-			vertices := (cast([^]rl.Vector3)mesh.vertices)[:mesh.vertexCount]
-			indices := mesh.indices[:mesh.triangleCount * 3]
+			vert_count += int(mesh.vertexCount)
+			indices_count += int(mesh.triangleCount * 3)
+		}
+		vertices := make([]bvh.Vec3, vert_count)
+		indices := make([]u16, indices_count)
 
-			mesh_bvh := bvh.build_bvh_from_mesh(
-				{vertices = vertices, indices = indices},
-				context.allocator,
-			)
+		vert_count = 0
+		indices_count = 0
+		for i in 0 ..< model.meshCount {
+			mesh := model.meshes[i]
+			mesh_vertices := (cast([^]rl.Vector3)mesh.vertices)[:mesh.vertexCount]
+			mesh_indices := mesh.indices[:mesh.triangleCount * 3]
 
-			root_aabb := mesh_bvh.bvh.nodes[0].aabb
-			outer_aabb.min = lg.min(outer_aabb.min, root_aabb.min)
-			outer_aabb.max = lg.max(outer_aabb.max, root_aabb.max)
+			copy(vertices[vert_count:], mesh_vertices)
 
-			new_bvhs[i] = mesh_bvh.bvh
+			for j in 0 ..< len(mesh_indices) {
+				indices[indices_count + j] = u16(vert_count) + mesh_indices[j]
+			}
+
+			vert_count += len(mesh_vertices)
+			indices_count += len(mesh_indices)
 		}
 
+
+		mesh_bvh := bvh.build_bvh_from_mesh(
+			{vertices = vertices, indices = indices},
+			context.allocator,
+		)
+
+		root_aabb := mesh_bvh.bvh.nodes[0].aabb
+
 		assetman.bvhs[path] = Loaded_BVH {
-			aabb    = outer_aabb,
-			bvhs    = new_bvhs,
-			modtime = modtime,
+			aabb     = root_aabb,
+			bvh      = mesh_bvh.bvh,
+			vertices = vertices,
+			indices  = indices,
+			modtime  = modtime,
 		}
 	}
 
-	return assetman.bvhs[path]
+	return assetman.bvhs[path], should_recreate
 }
 
 get_curve_1d :: proc(assetman: ^Asset_Manager, path: cstring) -> (curve: []f32) {
@@ -827,8 +853,8 @@ shutdown :: proc(assetman: ^Asset_Manager) {
 	assetcache_destroy(&assetman.curves_1d)
 	assetcache_destroy(&assetman.curves_2d)
 
-	for _, loaded_bvh in assetman.bvhs {
-		destroy_loaded_bvh(loaded_bvh)
+	for _, &loaded_bvh in assetman.bvhs {
+		destroy_loaded_bvh(&loaded_bvh)
 	}
 	delete(assetman.bvhs)
 }

game/game.odin

@@ -22,7 +22,6 @@ import "core:log"
 import "core:math"
 import "core:math/linalg"
 import "game:physics"
-import "game:physics/bvh"
 import "game:render"
 import rl "libs:raylib"
 import "libs:raylib/rlgl"
@@ -59,6 +58,9 @@ World :: struct {
 	engine_handle: physics.Engine_Handle,
 	debug_state:   Debug_Draw_State,
 }
+world_init :: proc(world: ^World) {
+	physics.scene_init(&world.physics_scene, &g_mem.assetman)
+}
 copy_world :: proc(dst, src: ^World) {
 	copy_track(&dst.track, &src.track)
 	physics.copy_physics_scene(&dst.physics_scene, &src.physics_scene)
@@ -71,7 +73,7 @@ copy_world :: proc(dst, src: ^World) {
 }
 destroy_world :: proc(world: ^World) {
 	destroy_track(&world.track)
-	physics.destroy_physics_scene(&world.physics_scene)
+	physics.scene_destroy(&world.physics_scene)
 }
 
 Runtime_World :: struct {
@@ -91,6 +93,7 @@ Runtime_World :: struct {
 runtime_world_init :: proc(runtime_world: ^Runtime_World, num_snapshots: int = 2) {
 	runtime_world.world_snapshots = make([]World, num_snapshots)
 	world := runtime_world_current_world(runtime_world)
+	physics.scene_init(&world.physics_scene, &g_mem.assetman)
 	world.debug_state.show_menu = true
 	world.debug_state.draw_physics_scene = true
 }
@@ -125,7 +128,6 @@ Game_Memory :: struct {
 	name_container: name.Container,
 	assetman:       assets.Asset_Manager,
 	runtime_world:  Runtime_World,
-	fluid_scene:    Fluid_Scene,
 	es:             Editor_State,
 	ui_context:     ui.Context,
 	default_font:   rl.Font,
@@ -169,6 +171,8 @@ world_stack_init :: proc(stack: ^World_Stack, num_snapshots: int, allocator := c
 	assert(num_snapshots > 0)
 	stack.worlds = make([]World, num_snapshots, allocator)
 	world_stack_push(stack)
+
+	world_init(world_stack_current(stack))
 }
 
 world_stack_destroy :: proc(stack: ^World_Stack, allocator := context.allocator) {
@@ -695,6 +699,20 @@ update_world :: proc(world: ^World, dt: f32, config: World_Update_Config) {
 			wheel.turn_angle = TURN_ANGLE * turn_vel_correction * turn_input
 		}
 
+		{
+			physics.immediate_level_geom(
+				&world.physics_scene,
+				u32(name.from_string("level_geom_from_asset")),
+				{
+					position = physics.Vec3{5, 0, 0},
+					rotation = linalg.QUATERNIONF32_IDENTITY,
+					source = physics.Level_Geometry_Asset(
+						"assets/blender/test_level_blend/NurbsPath.glb",
+					),
+				},
+			)
+		}
+
 		{
 			level_model := assets.get_model(&g_mem.assetman, "assets/testblend.glb")
 
@@ -712,8 +730,10 @@ update_world :: proc(world: ^World, dt: f32, config: World_Update_Config) {
 						{
 							position = pos,
 							rotation = rotation,
-							vertices = (cast([^]rl.Vector3)mesh.vertices)[:mesh.vertexCount],
-							indices = mesh.indices[:mesh.triangleCount * 3],
+							source = physics.Level_Geometry_Mesh {
+								vertices = (cast([^]rl.Vector3)mesh.vertices)[:mesh.vertexCount],
+								indices = mesh.indices[:mesh.triangleCount * 3],
+							},
 						},
 					)
 				}
@@ -734,8 +754,10 @@ update_world :: proc(world: ^World, dt: f32, config: World_Update_Config) {
 				#hash("track", "fnv32a"),
 				{
 					rotation = linalg.QUATERNIONF32_IDENTITY,
-					vertices = track_verts,
-					indices = track_inds,
+					source = physics.Level_Geometry_Mesh {
+						vertices = track_verts,
+						indices = track_inds,
+					},
 				},
 			)
 		}
@@ -973,33 +995,33 @@ update :: proc() {
 	dt := rl.GetFrameTime()
 
 	// Debug BVH traversal
-	mesh_bvh := assets.get_bvh(&g_mem.assetman, "assets/toyota_corolla_ae86_trueno.glb")
+	// mesh_bvh := assets.get_bvh(&g_mem.assetman, "assets/toyota_corolla_ae86_trueno.glb")
 
-	if rl.IsKeyDown(.LEFT_SHIFT) {
-		if g_mem.preview_bvh >= 0 && g_mem.preview_bvh < len(mesh_bvh.bvhs) {
-			b := mesh_bvh.bvhs[g_mem.preview_bvh]
-			node := &b.nodes[g_mem.preview_node]
+	// if rl.IsKeyDown(.LEFT_SHIFT) {
+	// 	if g_mem.preview_bvh >= 0 && g_mem.preview_bvh < len(mesh_bvh.bvhs) {
+	// 		b := mesh_bvh.bvhs[g_mem.preview_bvh]
+	// 		node := &b.nodes[g_mem.preview_node]
 
-			if !bvh.is_leaf_node(node^) {
-				if rl.IsKeyPressed(.LEFT_BRACKET) {
-					g_mem.preview_node = int(node.child_or_prim_start)
-				} else if rl.IsKeyPressed(.RIGHT_BRACKET) {
-					g_mem.preview_node = int(node.child_or_prim_start + 1)
-				} else if rl.IsKeyPressed(.P) {
-					g_mem.preview_node = 0
-				}
-			}
-		}
-	} else {
-		if rl.IsKeyPressed(.LEFT_BRACKET) {
-			g_mem.preview_bvh -= 1
-			g_mem.preview_node = 0
-		}
-		if rl.IsKeyPressed(.RIGHT_BRACKET) {
-			g_mem.preview_bvh += 1
-			g_mem.preview_node = 0
-		}
-	}
+	// 		if !bvh.is_leaf_node(node^) {
+	// 			if rl.IsKeyPressed(.LEFT_BRACKET) {
+	// 				g_mem.preview_node = int(node.child_or_prim_start)
+	// 			} else if rl.IsKeyPressed(.RIGHT_BRACKET) {
+	// 				g_mem.preview_node = int(node.child_or_prim_start + 1)
+	// 			} else if rl.IsKeyPressed(.P) {
+	// 				g_mem.preview_node = 0
+	// 			}
+	// 		}
+	// 	}
+	// } else {
+	// 	if rl.IsKeyPressed(.LEFT_BRACKET) {
+	// 		g_mem.preview_bvh -= 1
+	// 		g_mem.preview_node = 0
+	// 	}
+	// 	if rl.IsKeyPressed(.RIGHT_BRACKET) {
+	// 		g_mem.preview_bvh += 1
+	// 		g_mem.preview_node = 0
+	// 	}
+	// }
 
 	if rl.IsKeyPressed(.SPACE) {
 		g_mem.physics_pause = !g_mem.physics_pause
@@ -1429,9 +1451,9 @@ game_init :: proc() {
 	name.init(&g_mem.name_container)
 	name.setup_global_container(&g_mem.name_container)
 	init_physifs_raylib_callbacks()
-	assets.assetman_init(&g_mem.assetman)
 
-	fluid_scene_init(&g_mem.fluid_scene)
+	assets.assetman_init(&g_mem.assetman)
+	assets.init(&g_mem.assetman)
 
 	editor_state_init(&g_mem.es, 100)
 	runtime_world_init(&g_mem.runtime_world, DEV_BUILD ? 100 : 2)
@@ -1454,7 +1476,6 @@ game_shutdown :: proc() {
 	editor_state_destroy(&g_mem.es)
 	delete(g_mem.es.point_selection)
 	runtime_world_destroy(&g_mem.runtime_world)
-	fluid_scene_destroy(&g_mem.fluid_scene)
 
 	free(g_mem)
 }

game/physics/helpers.odin

@@ -1,5 +1,6 @@
 package physics
 
+import "bvh"
 import "collision"
 import "core:log"
 import "core:math"
@@ -299,13 +300,14 @@ body_get_convex_shapes_world :: proc(
 
 level_geom_get_convex_shape :: proc(
 	sim_state: ^Sim_State,
-	level_geom: Level_Geom_Ptr,
+	level_geom_handle: Level_Geom_Handle,
 	tri_idx: int,
 	allocator := context.temp_allocator,
 ) -> (
 	mesh: collision.Convex,
 ) {
-	vertices, indices := get_level_geom_data(sim_state, level_geom.geometry)
+	level_geom := get_level_geom(sim_state, level_geom_handle)
+	vertices, indices := get_level_geom_data(sim_state, level_geom_handle)
 	return collision.double_sided_triangle_to_convex(
 		get_transformed_triangle(vertices, indices, tri_idx, level_geom.x, level_geom.q),
 		allocator,
@@ -396,3 +398,8 @@ rpm_to_angular_velocity :: proc(rpm: f32) -> f32 {
 angular_velocity_to_rpm :: proc(w: f32) -> f32 {
 	return (w / (2.0 * math.PI)) * 60.0
 }
+
+// TODO: use one format everywhere...
+bvh_aabb_to_phys_aabb :: proc(aabb: bvh.AABB) -> AABB {
+	return AABB{center = (aabb.max + aabb.min) * 0.5, extent = (aabb.max - aabb.min) * 0.5}
+}

game/physics/scene.odin

@@ -4,6 +4,8 @@ import "bvh"
 import "collision"
 import "common:name"
 import lg "core:math/linalg"
+import "core:strings"
+import "game:assets"
 import "game:container/spanpool"
 import "libs:tracy"
 
@@ -78,6 +80,7 @@ contact_container_copy :: proc(dst: ^Contact_Container, src: Contact_Container)
 }
 
 Sim_State :: struct {
+	scene:                                     ^Scene,
 	bodies:                                    #soa[dynamic]Body,
 	suspension_constraints:                    #soa[dynamic]Suspension_Constraint,
 	engines:                                   [dynamic]Engine,
@@ -120,6 +123,7 @@ Sim_State :: struct {
 }
 
 Scene :: struct {
+	assetman:               ^assets.Asset_Manager,
 	simulation_states:      [2]Sim_State,
 	simulation_state_index: i32,
 	solver_state:           Solver_State,
@@ -130,6 +134,7 @@ copy_sim_state :: proc(dst: ^Sim_State, src: ^Sim_State) {
 	tracy.Zone()
 	convex_container_reconcile(&src.convex_container)
 
+	dst.scene = src.scene
 	dst.num_bodies = src.num_bodies
 	dst.first_free_body_plus_one = src.first_free_body_plus_one
 	dst.first_free_suspension_constraint_plus_one = src.first_free_suspension_constraint_plus_one
@@ -168,12 +173,12 @@ copy_sim_state :: proc(dst: ^Sim_State, src: ^Sim_State) {
 copy_physics_scene :: proc(dst, src: ^Scene) {
 	tracy.Zone()
 
+	dst.assetman = src.assetman
 	dst.simulation_state_index = src.simulation_state_index
 	src_sim_state := get_sim_state(src)
 	dst_sim_state := get_sim_state(dst)
 
 	copy_sim_state(dst_sim_state, src_sim_state)
-
 	copy_solver_state(&dst.solver_state, &src.solver_state)
 }
 
@@ -391,11 +396,24 @@ BLAS_Handle :: struct {
 	primitives: spanpool.Handle,
 }
 
+Level_Geom_Source_Local :: struct {
+	geometry: Geometry_Handle,
+	blas:     BLAS_Handle,
+}
+
+Level_Geom_Source_Asset :: struct {
+	assetpath: name.Name,
+}
+
+Level_Geom_Source :: union #no_nil {
+	Level_Geom_Source_Local,
+	Level_Geom_Source_Asset,
+}
+
 Level_Geom :: struct {
 	alive:         bool,
 	aabb:          AABB,
-	geometry:      Geometry_Handle,
-	blas:          BLAS_Handle,
+	source:        Level_Geom_Source,
 	x:             Vec3,
 	q:             Quat,
 	next_plus_one: i32,
@@ -584,11 +602,23 @@ Engine_Config :: struct {
 	axle:               Drive_Axle_Config,
 }
 
+Level_Geometry_Asset :: distinct string
+
+Level_Geometry_Mesh :: struct {
+	vertices: []Vec3,
+	indices:  []u16,
+}
+
+// Either runtime mesh or asset reference which will be fetched from assetmanager
+Level_Geometry_Source :: union #no_nil {
+	Level_Geometry_Mesh,
+	Level_Geometry_Asset,
+}
+
 Level_Geom_Config :: struct {
 	position: Vec3,
 	rotation: Quat,
-	vertices: []Vec3,
-	indices:  []u16,
+	source:   Level_Geometry_Source,
 }
 
 calculate_body_params_from_config :: proc(
@@ -919,20 +949,50 @@ get_level_geom :: proc(sim_state: ^Sim_State, handle: Level_Geom_Handle) -> Leve
 
 get_level_geom_data :: proc(
 	sim_state: ^Sim_State,
-	handle: Geometry_Handle,
+	handle: Level_Geom_Handle,
 ) -> (
 	vertices: []Vec3,
 	indices: []u16,
 ) {
-	vertices = spanpool.resolve_slice(&sim_state.geometry_vertices_pool, handle.vertices)
-	indices = spanpool.resolve_slice(&sim_state.geometry_indices_pool, handle.indices)
+	level_geom := get_level_geom(sim_state, handle)
+
+	switch s in level_geom.source {
+	case Level_Geom_Source_Local:
+		vertices = spanpool.resolve_slice(&sim_state.geometry_vertices_pool, s.geometry.vertices)
+		indices = spanpool.resolve_slice(&sim_state.geometry_indices_pool, s.geometry.indices)
+	case Level_Geom_Source_Asset:
+		loaded_bvh, reloaded := assets.get_bvh(
+			sim_state.scene.assetman,
+			strings.unsafe_string_to_cstring(name.to_string(s.assetpath)),
+		)
+		if reloaded {
+			level_geom.aabb = bvh_aabb_to_phys_aabb(loaded_bvh.aabb)
+		}
+		vertices = loaded_bvh.vertices
+		indices = loaded_bvh.indices
+	}
+
 	return
 }
 
-get_level_geom_blas :: proc(sim_state: ^Sim_State, handle: BLAS_Handle) -> (bvh: bvh.BVH) {
-	bvh.nodes = spanpool.resolve_slice(&sim_state.blas_nodes_pool, handle.nodes)
-	bvh.primitives = spanpool.resolve_slice(&sim_state.blas_primitives_pool, handle.primitives)
-	bvh.nodes_used = i32(len(bvh.nodes))
+get_level_geom_blas :: proc(sim_state: ^Sim_State, handle: Level_Geom_Handle) -> (bvh: bvh.BVH) {
+	level_geom := get_level_geom(sim_state, handle)
+	switch s in level_geom.source {
+	case Level_Geom_Source_Local:
+		bvh.nodes = spanpool.resolve_slice(&sim_state.blas_nodes_pool, s.blas.nodes)
+		bvh.primitives = spanpool.resolve_slice(&sim_state.blas_primitives_pool, s.blas.primitives)
+		bvh.nodes_used = i32(len(bvh.nodes))
+	case Level_Geom_Source_Asset:
+		loaded_bvh, reloaded := assets.get_bvh(
+			sim_state.scene.assetman,
+			strings.unsafe_string_to_cstring(name.to_string(s.assetpath)),
+		)
+		if reloaded {
+			level_geom.aabb = bvh_aabb_to_phys_aabb(loaded_bvh.aabb)
+		}
+
+		bvh = loaded_bvh.bvh
+	}
 	return
 }
 
@@ -945,53 +1005,75 @@ update_level_geom_from_config :: proc(
 	level_geom.q = config.rotation
 
 	// TODO: figure out if asset changed and rebuild only then
+
+
 }
 
 add_level_geom :: proc(sim_state: ^Sim_State, config: Level_Geom_Config) -> Level_Geom_Handle {
-	assert(len(config.vertices) > 0)
-	assert(len(config.vertices) <= int(max(u16)))
-
 	sim_state.num_level_geoms += 1
 
 	level_geom: Level_Geom
 	level_geom.alive = true
 	update_level_geom_from_config(sim_state, &level_geom, config)
 
-	blas :=
-		bvh.build_bvh_from_mesh(bvh.Mesh{vertices = config.vertices, indices = config.indices}, context.temp_allocator).bvh
+	switch s in config.source {
+	case Level_Geometry_Mesh:
+		assert(len(s.vertices) > 0)
+		assert(len(s.vertices) <= int(max(u16)))
+		blas :=
+			bvh.build_bvh_from_mesh(bvh.Mesh{vertices = s.vertices, indices = s.indices}, context.temp_allocator).bvh
 
-	level_geom.blas.nodes = spanpool.allocate_elems(
-		&sim_state.blas_nodes_pool,
-		..blas.nodes[:blas.nodes_used],
-	)
-	level_geom.blas.primitives = spanpool.allocate_elems(
-		&sim_state.blas_primitives_pool,
-		..blas.primitives,
-	)
+		source: Level_Geom_Source_Local
+		source.blas.nodes = spanpool.allocate_elems(
+			&sim_state.blas_nodes_pool,
+			..blas.nodes[:blas.nodes_used],
+		)
+		source.blas.primitives = spanpool.allocate_elems(
+			&sim_state.blas_primitives_pool,
+			..blas.primitives,
+		)
 
-	aabb_min, aabb_max: Vec3 = max(f32), min(f32)
-	for v in config.vertices {
-		aabb_min = lg.min(aabb_min, v)
-		aabb_max = lg.max(aabb_max, v)
+		aabb_min, aabb_max: Vec3 = max(f32), min(f32)
+		for v in s.vertices {
+			aabb_min = lg.min(aabb_min, v)
+			aabb_max = lg.max(aabb_max, v)
+		}
+
+		level_geom.aabb.center = (aabb_max + aabb_min) * 0.5
+		level_geom.aabb.extent = (aabb_max - aabb_min) * 0.5
+
+		// if spanpool.is_handle_valid(
+		// 	&sim_state.geometry_vertices_pool,
+		// 	level_geom.geometry.vertices,
+		// ) {
+		// 	spanpool.free(&sim_state.geometry_vertices_pool, level_geom.geometry.vertices)
+		// 	spanpool.free(&sim_state.geometry_indices_pool, level_geom.geometry.indices)
+		// }
+
+		source.geometry.vertices = spanpool.allocate_elems(
+			&sim_state.geometry_vertices_pool,
+			..s.vertices,
+		)
+		source.geometry.indices = spanpool.allocate_elems(
+			&sim_state.geometry_indices_pool,
+			..s.indices,
+		)
+		level_geom.source = source
+	case Level_Geometry_Asset:
+		level_geom.source = Level_Geom_Source_Asset {
+			assetpath = name.from_string(string(s)),
+		}
+
+		bvh, _ := assets.get_bvh(
+			sim_state.scene.assetman,
+			strings.unsafe_string_to_cstring(string(s)),
+		)
+		level_geom.aabb = AABB {
+			center = (bvh.aabb.max + bvh.aabb.min) * 0.5,
+			extent = (bvh.aabb.max - bvh.aabb.min) * 0.5,
+		}
 	}
 
-	level_geom.aabb.center = (aabb_max + aabb_min) * 0.5
-	level_geom.aabb.extent = (aabb_max - aabb_min) * 0.5
-
-	if spanpool.is_handle_valid(&sim_state.geometry_vertices_pool, level_geom.geometry.vertices) {
-		spanpool.free(&sim_state.geometry_vertices_pool, level_geom.geometry.vertices)
-		spanpool.free(&sim_state.geometry_indices_pool, level_geom.geometry.indices)
-	}
-
-	level_geom.geometry.vertices = spanpool.allocate_elems(
-		&sim_state.geometry_vertices_pool,
-		..config.vertices,
-	)
-	level_geom.geometry.indices = spanpool.allocate_elems(
-		&sim_state.geometry_indices_pool,
-		..config.indices,
-	)
-
 	if sim_state.first_free_level_geom_plus_one > 0 {
 		index := sim_state.first_free_level_geom_plus_one
 		new_level_geom := get_level_geom(sim_state, Level_Geom_Handle(index))
@@ -1009,11 +1091,15 @@ add_level_geom :: proc(sim_state: ^Sim_State, config: Level_Geom_Config) -> Leve
 remove_level_geom :: proc(sim_state: ^Sim_State, handle: Level_Geom_Handle) {
 	level_geom := get_level_geom(sim_state, handle)
 
-	spanpool.free(&sim_state.geometry_vertices_pool, level_geom.geometry.vertices)
-	spanpool.free(&sim_state.geometry_indices_pool, level_geom.geometry.indices)
+	switch s in level_geom.source {
+	case Level_Geom_Source_Local:
+		spanpool.free(&sim_state.geometry_vertices_pool, s.geometry.vertices)
+		spanpool.free(&sim_state.geometry_indices_pool, s.geometry.indices)
 
-	spanpool.free(&sim_state.blas_nodes_pool, level_geom.blas.nodes)
-	spanpool.free(&sim_state.blas_primitives_pool, level_geom.blas.primitives)
+		spanpool.free(&sim_state.blas_nodes_pool, s.blas.nodes)
+		spanpool.free(&sim_state.blas_primitives_pool, s.blas.primitives)
+	case Level_Geom_Source_Asset:
+	}
 }
 
 _get_first_free_body :: proc(sim_state: ^Sim_State) -> i32 {
@@ -1039,7 +1125,14 @@ destry_sim_state :: proc(sim_state: ^Sim_State) {
 	dynamic_tlas_destroy(&sim_state.dynamic_tlas)
 }
 
-destroy_physics_scene :: proc(scene: ^Scene) {
+scene_init :: proc(scene: ^Scene, assetman: ^assets.Asset_Manager) {
+	scene.assetman = assetman
+	for &sim_state in scene.simulation_states {
+		sim_state.scene = scene
+	}
+}
+
+scene_destroy :: proc(scene: ^Scene) {
 	for &sim_state in scene.simulation_states {
 		destry_sim_state(&sim_state)
 	}

game/physics/simulation.odin

@@ -200,9 +200,8 @@ raycasts_level :: proc(
 			level_geom_handle := index_to_level_geom(
 				int(tlas.bvh_tree.primitives[leaf_node.child_or_prim_start + j]),
 			)
-			level_geom := get_level_geom(sim_state, level_geom_handle)
-			blas := get_level_geom_blas(sim_state, level_geom.blas)
-			vertices, indices := get_level_geom_data(sim_state, level_geom.geometry)
+			blas := get_level_geom_blas(sim_state, level_geom_handle)
+			vertices, indices := get_level_geom_data(sim_state, level_geom_handle)
 
 			// TODO: transform ray into blas space and back
 
@@ -388,7 +387,7 @@ remove_invalid_contacts :: proc(
 
 				if !should_remove {
 					tri_idx := int(contact.local_tri_idx)
-					vertices, indices := get_level_geom_data(sim_state, level_geom.geometry)
+					vertices, indices := get_level_geom_data(sim_state, level_geom_handle)
 					should_remove |= tri_idx * 3 >= len(indices)
 
 					if !should_remove {
@@ -547,11 +546,8 @@ find_new_contacts :: proc(
 						)
 						level_geom := get_level_geom(sim_state, level_geom_handle)
 						if level_geom.alive {
-							blas := get_level_geom_blas(sim_state, level_geom.blas)
-							vertices, indices := get_level_geom_data(
-								sim_state,
-								level_geom.geometry,
-							)
+							blas := get_level_geom_blas(sim_state, level_geom_handle)
+							vertices, indices := get_level_geom_data(sim_state, level_geom_handle)
 
 							blas_it := bvh.iterator_intersect_leaf_aabb(&blas, body_aabb)
 							for blas_leaf_node in bvh.iterator_intersect_leaf_next(&blas_it) {
@@ -808,8 +804,7 @@ update_contacts :: proc(sim_state: ^Sim_State, static_tlas: ^Static_TLAS) {
 			)
 		case .Body_vs_Level:
 			level_geom_handle := Level_Geom_Handle(contact.b)
-			level_geom := get_level_geom(sim_state, level_geom_handle)
-			vertices, indices := get_level_geom_data(sim_state, level_geom.geometry)
+			vertices, indices := get_level_geom_data(sim_state, level_geom_handle)
 			tri := get_triangle(vertices, indices, int(contact.local_tri_idx))
 
 			m2 = collision.double_sided_triangle_to_convex(tri, context.temp_allocator)

src_assets/blender_assets.cats.txt

@@ -0,0 +1,9 @@
+# This is an Asset Catalog Definition file for Blender.
+#
+# Empty lines and lines starting with `#` will be ignored.
+# The first non-ignored line should be the version indicator.
+# Other lines are of the format "UUID:catalog/path/for/assets:simple catalog name"
+
+VERSION 1
+
+65988f84-4b5f-463a-bcae-896eba4975c5:Buildings:Buildings

src_assets/blender_assets.cats.txt~

@@ -0,0 +1,9 @@
+# This is an Asset Catalog Definition file for Blender.
+#
+# Empty lines and lines starting with `#` will be ignored.
+# The first non-ignored line should be the version indicator.
+# Other lines are of the format "UUID:catalog/path/for/assets:simple catalog name"
+
+VERSION 1
+
+65988f84-4b5f-463a-bcae-896eba4975c5:Buildings:Buildings