Improve generated river terrain

docs/DEVELOPMENT.md

@@ -261,9 +261,11 @@ copies of the entire customization catalog.
 
 ### Texture sampling
 
-NETfishing artwork always uses nearest-neighbor sampling. Do not enable linear,
-bilinear, trilinear, or anisotropic texture filtering, and do not generate
-mipmaps. Shader samplers must declare `filter_nearest`. The
+NETfishing artwork uses nearest-neighbor sampling. Do not enable linear,
+bilinear, trilinear, or anisotropic texture filtering. Shader samplers must
+declare `filter_nearest`. The three canonical repeating terrain textures are
+the sole mipmap exception: their projected shader uses nearest-filtered
+mipmaps to prevent distance aliasing without smoothing nearby pixels. The
 `TextureSamplingPolicy` autoload applies nearest sampling to 2D canvas items,
 Sprite3D presentations, imported 3D materials, and dynamically constructed
 mesh materials at runtime.

scripts/normalize_texture_imports.gd

@@ -31,6 +31,11 @@ const FACIAL_FEATURE_IMPORT_PATH: String = (
 	"art/exported/characters/faces/"
 )
 const FACIAL_FEATURE_SIZE_LIMIT: int = 512
+const PROJECTED_TERRAIN_TEXTURE_IMPORTS: Array[String] = [
+	"res://world/generation/chunks/assets/chunk_0000_grass_lite.png.import",
+	"res://world/generation/chunks/assets/chunk_0001_sand.png.import",
+	"res://world/generation/chunks/assets/chunk_0031_dirt.png.import",
+]
 
 var apply_changes: bool = false
 var verbose: bool = false
@@ -153,6 +158,8 @@ func _handle_import_file(import_path: String) -> void:
 			var desired: Variant = section_data[section_key]
 			if section_key == "process/size_limit":
 				desired = _size_limit_for(import_path)
+			elif section_key == "mipmaps/generate":
+				desired = _generates_mipmaps(import_path)
 			var existing: Variant = null
 			if cfg.has_section(section_name) and cfg.has_section_key(section_name, section_key):
 				existing = cfg.get_value(section_name, section_key)
@@ -187,6 +194,11 @@ func _size_limit_for(import_path: String) -> int:
 	return int(DEFAULT_PROFILE["params"]["process/size_limit"])
 
 
+func _generates_mipmaps(import_path: String) -> bool:
+	var normalized_path := import_path.replace("\\", "/")
+	return normalized_path in PROJECTED_TERRAIN_TEXTURE_IMPORTS
+
+
 func print_summary() -> void:
 	if apply_changes:
 		_print(

tests/generated_world_runtime_validation.gd

@@ -247,6 +247,7 @@ func _validate_generated_region(
 	assert(_placement_count(placements, "chunk_0034") == 1)
 	assert(_placement_count(placements, "chunk_0035") == 1)
 	assert(_placement_count(placements, "chunk_0036") == 1)
+	assert(_placement_count(placements, "chunk_0038") == 2)
 	assert(
 		_placement_count(placements, "chunk_0014")
 		== (2 if has_secondary_elevation else 0)
@@ -285,10 +286,31 @@ func _validate_generated_region(
 	var river_edge_count := (
 		_placement_count(placements, "chunk_0024")
 		+ _placement_count(placements, "chunk_0025")
+		+ _placement_count(placements, "chunk_0038")
 	)
 	assert(river_coordinate_count >= 12)
 	assert(generator._river_feature_placements.size() == river_coordinate_count)
 	assert(river_edge_count == river_coordinate_count - 8)
+	var stone_bridge_specs: Array[Dictionary] = []
+	for spec: Dictionary in generator._river_feature_placements:
+		if spec.get("id", &"") == &"chunk_0038":
+			stone_bridge_specs.append(spec)
+	assert(stone_bridge_specs.size() == 2)
+	var first_bridge_coordinate := stone_bridge_specs[0].get(
+		"coordinate",
+		Vector2i(-1, -1),
+	) as Vector2i
+	var second_bridge_coordinate := stone_bridge_specs[1].get(
+		"coordinate",
+		Vector2i(-1, -1),
+	) as Vector2i
+	var bridge_delta := second_bridge_coordinate - first_bridge_coordinate
+	assert(absi(bridge_delta.x) + absi(bridge_delta.y) == 1)
+	assert(posmod(
+		int(stone_bridge_specs[1].get("turns", -1))
+		- int(stone_bridge_specs[0].get("turns", -1)),
+		4,
+	) == 2)
 	var river_source_coordinates := generator._river_source_coordinates(
 		generator._river_feature_origin,
 		generator._river_feature_footprint_size,
@@ -446,6 +468,20 @@ func _validate_generated_region(
 		assert(fresh.surface_size.x <= 10.0 and fresh.surface_size.y <= 10.0)
 		assert(not fresh.visual_surface_enabled)
 		assert(not (fresh.get_node("VisualWater") as MeshInstance3D).visible)
+		var generated_bed := fresh.get_node_or_null(
+			"GeneratedBed",
+		) as MeshInstance3D
+		assert(generated_bed != null and generated_bed.mesh != null)
+		assert(
+			is_equal_approx(
+				generated_bed.global_position.y,
+				GeneratedWorldRegion.GENERATED_FRESH_WATER_BED_HEIGHT,
+			)
+		)
+		assert(
+			generated_bed.material_override != null
+			and generated_bed.material_override.resource_name == "dirt"
+		)
 		var fresh_recovery := (
 			fresh.get_node("RecoveryRegion") as PlayerWaterTrigger
 		)
@@ -486,6 +522,16 @@ func _validate_generated_region(
 	)
 
 	var decorations := region.get_node("Decorations") as Node3D
+	var grass_prop_surface_triangles := region.get_spawn_surface_triangles(
+		[&"grass_lite"],
+		-INF,
+		0.35,
+	)
+	var sand_prop_surface_triangles := region.get_spawn_surface_triangles(
+		[&"sand"],
+		-INF,
+		0.35,
+	)
 	var anchors := region.get_node(
 		"GatherableAnchors/ReachableTreeTrunks"
 	) as GatherableAnchorSet3D
@@ -540,6 +586,8 @@ func _validate_generated_region(
 			region,
 			child as Node3D,
 			definition,
+			grass_prop_surface_triangles,
+			sand_prop_surface_triangles,
 		)
 		if prop_id == &"prop_palm":
 			var cluster_id := int(
@@ -1063,6 +1111,8 @@ func _validate_decoration_transform(
 	region: GeneratedWorldRegion,
 	prop: Node3D,
 	definition: TerrainPropDefinition,
+	grass_surface_triangles: Array[PackedVector3Array],
+	sand_surface_triangles: Array[PackedVector3Array],
 ) -> void:
 	assert(prop != null)
 	assert(prop.scale.is_equal_approx(Vector3.ONE))
@@ -1142,6 +1192,43 @@ func _validate_decoration_transform(
 				],
 		],
 	)
+	var required_surface_triangles: Array[PackedVector3Array] = (
+		sand_surface_triangles
+		if definition.procedural_group == &"sand_tree"
+		else grass_surface_triangles
+	)
+	var required_surface_height := _triangle_surface_height_at(
+		prop.global_position,
+		required_surface_triangles,
+	)
+	assert(
+		required_surface_height > -INF
+		and absf(required_surface_height - prop.global_position.y) <= 0.01,
+		"%s (%s) is not rooted on its required terrain material at %s."
+		% [prop.name, definition.stable_id, prop.global_position],
+	)
+
+
+func _triangle_surface_height_at(
+	position: Vector3,
+	triangles: Array[PackedVector3Array],
+) -> float:
+	var highest := -INF
+	var segment_start := position + Vector3.UP * 100.0
+	var segment_end := position + Vector3.DOWN * 100.0
+	for triangle: PackedVector3Array in triangles:
+		if triangle.size() != 3:
+			continue
+		var hit: Variant = Geometry3D.segment_intersects_triangle(
+			segment_start,
+			segment_end,
+			triangle[0],
+			triangle[1],
+			triangle[2],
+		)
+		if hit is Vector3:
+			highest = maxf(highest, (hit as Vector3).y)
+	return highest
 
 
 func _validate_tree_gatherable_anchors(

tests/terrain_chunk_generator_validation.gd

@@ -42,6 +42,7 @@ const EXPECTED_IDS: Array[String] = [
 	"chunk_0035",
 	"chunk_0036",
 	"chunk_0037",
+	"chunk_0038",
 	"chunk_9999",
 	"chunk_9998",
 	"chunk_9997",
@@ -98,6 +99,7 @@ const EXPECTED_VARIANT_COUNTS: Dictionary[StringName, int] = {
 	&"chunk_0035": 4,
 	&"chunk_0036": 4,
 	&"chunk_0037": 4,
+	&"chunk_0038": 4,
 	&"chunk_9999": 4,
 	&"chunk_9998": 4,
 	&"chunk_9997": 4,
@@ -163,6 +165,7 @@ func _validate_catalog() -> void:
 	var lake_narrow_to_regular := CATALOG.definition_for_id(&"chunk_0023")
 	var river_edge := CATALOG.definition_for_id(&"chunk_0024")
 	var river_edge_variant := CATALOG.definition_for_id(&"chunk_0025")
+	var river_stone_bridge := CATALOG.definition_for_id(&"chunk_0038")
 	var river_source_right := CATALOG.definition_for_id(&"chunk_0029")
 	var river_source_left := CATALOG.definition_for_id(&"chunk_0030")
 	var river_outlet_right := CATALOG.definition_for_id(&"chunk_0031")
@@ -208,6 +211,7 @@ func _validate_catalog() -> void:
 			and lake_narrow_to_regular != null
 			and river_edge != null
 			and river_edge_variant != null
+			and river_stone_bridge != null
 			and river_source_right != null
 			and river_source_left != null
 			and river_outlet_right != null
@@ -255,6 +259,7 @@ func _validate_catalog() -> void:
 		and lake_narrow_to_regular != null
 		and river_edge != null
 		and river_edge_variant != null
+		and river_stone_bridge != null
 		and river_source_right != null
 		and river_source_left != null
 		and river_outlet_right != null
@@ -509,6 +514,8 @@ func _validate_catalog() -> void:
 			(
 				not river_edge.participates_in_base_solver
 				and not river_edge_variant.participates_in_base_solver
+				and not river_stone_bridge.participates_in_base_solver
+				and river_stone_bridge.maximum_placements == 2
 				and not river_source_right.participates_in_base_solver
 				and not river_source_left.participates_in_base_solver
 				and not river_outlet_right.participates_in_base_solver
@@ -522,6 +529,8 @@ func _validate_catalog() -> void:
 				and river_edge.water_outlet_edges == 14
 				and river_edge_variant.water_inlet_edges == 14
 				and river_edge_variant.water_outlet_edges == 14
+				and river_stone_bridge.water_inlet_edges == 14
+				and river_stone_bridge.water_outlet_edges == 14
 				and river_source_right.water_inlet_edges == 6
 				and river_source_right.water_outlet_edges == 6
 				and river_source_left.water_inlet_edges == 3
@@ -544,6 +553,7 @@ func _validate_catalog() -> void:
 				and river_cap.water_outlet_edges == 6
 				and river_edge.water_surface_polygon.size() == 13
 				and river_edge_variant.water_surface_polygon.size() == 13
+				and river_stone_bridge.water_surface_polygon.size() == 13
 				and river_source_right.water_surface_polygon.size() == 13
 				and river_source_left.water_surface_polygon.size() == 13
 				and river_outlet_right.water_surface_polygon.size() == 19
@@ -554,6 +564,8 @@ func _validate_catalog() -> void:
 				and river_cap.primary_mesh_name == &"chunk_0020"
 				and "river" in river_edge.tags
 				and "river" in river_edge_variant.tags
+				and "river_bridge" in river_stone_bridge.tags
+				and "stepping_stones" in river_stone_bridge.tags
 				and "river_source_right" in river_source_right.tags
 				and "river_source_left" in river_source_left.tags
 				and "river_outlet_right" in river_outlet_right.tags
@@ -1461,6 +1473,10 @@ func _validate_authored_rotations(generator: TerrainChunkGenerator) -> void:
 	var river_edge_variant_bottom := _find_variant(generator, &"chunk_0025", 2)
 	var river_edge_vertical_left := _find_variant(generator, &"chunk_0024", 1)
 	var river_edge_vertical_right := _find_variant(generator, &"chunk_0025", 3)
+	var river_stones_top := _find_variant(generator, &"chunk_0038", 0)
+	var river_stones_bottom := _find_variant(generator, &"chunk_0038", 2)
+	var river_stones_left := _find_variant(generator, &"chunk_0038", 1)
+	var river_stones_right := _find_variant(generator, &"chunk_0038", 3)
 	var river_source_right := _find_variant(generator, &"chunk_0029", 0)
 	var river_source_left := _find_variant(generator, &"chunk_0030", 0)
 	var river_outlet_right := _find_variant(generator, &"chunk_0031", 0)
@@ -1500,6 +1516,10 @@ func _validate_authored_rotations(generator: TerrainChunkGenerator) -> void:
 			and river_edge_variant_bottom != null
 			and river_edge_vertical_left != null
 			and river_edge_vertical_right != null
+			and river_stones_top != null
+			and river_stones_bottom != null
+			and river_stones_left != null
+			and river_stones_right != null
 			and river_source_right != null
 			and river_source_left != null
 			and river_outlet_right != null
@@ -1525,6 +1545,10 @@ func _validate_authored_rotations(generator: TerrainChunkGenerator) -> void:
 		and river_edge_variant_bottom != null
 		and river_edge_vertical_left != null
 		and river_edge_vertical_right != null
+		and river_stones_top != null
+		and river_stones_bottom != null
+		and river_stones_left != null
+		and river_stones_right != null
 		and river_source_right != null
 		and river_source_left != null
 		and river_outlet_right != null
@@ -1535,6 +1559,30 @@ func _validate_authored_rotations(generator: TerrainChunkGenerator) -> void:
 		and river_bend_d != null
 		and beach_east != null
 	):
+		_check(
+			generator._edges_are_compatible(
+				river_edge_top,
+				TerrainChunkTopology.Edge.EAST,
+				river_stones_top,
+				TerrainChunkTopology.Edge.WEST,
+			)
+			and generator._edges_are_compatible(
+				river_stones_top,
+				TerrainChunkTopology.Edge.SOUTH,
+				river_stones_bottom,
+				TerrainChunkTopology.Edge.NORTH,
+			)
+			and generator._edges_are_compatible(
+				river_stones_left,
+				TerrainChunkTopology.Edge.EAST,
+				river_stones_right,
+				TerrainChunkTopology.Edge.WEST,
+			),
+			(
+				"The stepping-stone banks must replace one paired straight river "
+				+ "station in either orientation."
+			),
+		)
 		_check(
 			generator._edges_are_compatible(
 				river_source_right,
@@ -1750,8 +1798,8 @@ func _validate_authored_rotations(generator: TerrainChunkGenerator) -> void:
 func _validate_generation_summary(generator: TerrainChunkGenerator) -> void:
 	var summary := generator._build_summary()
 	_check(
-		int(summary.get("variant_count", 0)) == 170,
-		"The current catalog must expose all 170 authored rotations.",
+		int(summary.get("variant_count", 0)) == 174,
+		"The current catalog must expose all 174 authored rotations.",
 	)
 	_check(
 		int(summary.get("solver_variant_count", 0))

tests/texture_sampling_validation.gd

@@ -1,6 +1,11 @@
 extends SceneTree
 
 const POLICY := preload("res://main/texture_sampling_policy.gd")
+const PROJECTED_TERRAIN_TEXTURE_IMPORTS: Array[String] = [
+	"res://world/generation/chunks/assets/chunk_0000_grass_lite.png.import",
+	"res://world/generation/chunks/assets/chunk_0001_sand.png.import",
+	"res://world/generation/chunks/assets/chunk_0031_dirt.png.import",
+]
 
 var failures: Array[String] = []
 
@@ -83,9 +88,14 @@ func _validate_repository_files(path: String) -> void:
 
 func _validate_import_file(path: String) -> void:
 	var source := FileAccess.get_file_as_string(path)
+	var expects_mipmaps := path in PROJECTED_TERRAIN_TEXTURE_IMPORTS
 	_check(
-		"mipmaps/generate=true" not in source,
-		"Texture import generates mipmaps: %s" % path,
+		("mipmaps/generate=true" in source) == expects_mipmaps,
+		(
+			"Projected terrain mipmap policy mismatch: %s"
+			if expects_mipmaps
+			else "Texture import generates unapproved mipmaps: %s"
+		) % path,
 	)
 
 

world/generation/chunks/assets/chunk_0000_grass_lite.png.import

@@ -28,7 +28,7 @@ compress/rdo_quality_loss=0.0
 compress/hdr_compression=1
 compress/normal_map=0
 compress/channel_pack=0
-mipmaps/generate=false
+mipmaps/generate=true
 mipmaps/limit=-1
 roughness/mode=0
 roughness/src_normal=""

world/generation/chunks/assets/chunk_0001_sand.png.import

@@ -28,7 +28,7 @@ compress/rdo_quality_loss=0.0
 compress/hdr_compression=1
 compress/normal_map=0
 compress/channel_pack=0
-mipmaps/generate=false
+mipmaps/generate=true
 mipmaps/limit=-1
 roughness/mode=0
 roughness/src_normal=""

world/generation/chunks/assets/chunk_0031_dirt.png.import

@@ -28,7 +28,7 @@ compress/rdo_quality_loss=0.0
 compress/hdr_compression=1
 compress/normal_map=0
 compress/channel_pack=0
-mipmaps/generate=false
+mipmaps/generate=true
 mipmaps/limit=-1
 roughness/mode=0
 roughness/src_normal=""

world/generation/chunks/assets/chunk_0038.glb.import

@@ -0,0 +1,45 @@
+[remap]
+
+importer="scene"
+importer_version=1
+type="PackedScene"
+uid="uid://b3gl4nmbcgb6i"
+path="res://.godot/imported/chunk_0038.glb-aab0f64bae856fb9a86c3367af401891.scn"
+
+[deps]
+
+source_file="res://world/generation/chunks/assets/chunk_0038.glb"
+dest_files=["res://.godot/imported/chunk_0038.glb-aab0f64bae856fb9a86c3367af401891.scn"]
+
+[params]
+
+nodes/root_type=""
+nodes/root_name=""
+nodes/root_script=null
+mesh_library/use_node_names_as_mesh_names=false
+array_mesh/deduplicate_surfaces=true
+nodes/apply_root_scale=true
+nodes/root_scale=1.0
+nodes/import_as_skeleton_bones=false
+nodes/use_name_suffixes=true
+nodes/use_node_type_suffixes=true
+meshes/ensure_tangents=true
+meshes/generate_lods=true
+meshes/create_shadow_meshes=true
+meshes/light_baking=1
+meshes/lightmap_texel_size=0.2
+meshes/force_disable_compression=false
+skins/use_named_skins=true
+animation/import=true
+animation/fps=30
+animation/trimming=false
+animation/remove_immutable_tracks=true
+animation/import_rest_as_RESET=false
+import_script/path=""
+materials/extract=0
+materials/extract_format=0
+materials/extract_path=""
+_subresources={}
+gltf/naming_version=2
+gltf/embedded_image_handling=1
+gltf/texture_map_mode=1

world/generation/chunks/assets/chunk_0038_cliff_wall.png.import

@@ -0,0 +1,45 @@
+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://wmom2kmvf0sb"
+path.s3tc="res://.godot/imported/chunk_0038_cliff_wall.png-43b1f2500c61c119fe3d6dd64d103bce.s3tc.ctex"
+path.etc2="res://.godot/imported/chunk_0038_cliff_wall.png-43b1f2500c61c119fe3d6dd64d103bce.etc2.ctex"
+metadata={
+"imported_formats": ["s3tc_bptc", "etc2_astc"],
+"vram_texture": true
+}
+generator_parameters={
+"md5": "fc97184f537cc23f83a731327e10c836"
+}
+
+[deps]
+
+source_file="res://world/generation/chunks/assets/chunk_0038_cliff_wall.png"
+dest_files=["res://.godot/imported/chunk_0038_cliff_wall.png-43b1f2500c61c119fe3d6dd64d103bce.s3tc.ctex", "res://.godot/imported/chunk_0038_cliff_wall.png-43b1f2500c61c119fe3d6dd64d103bce.etc2.ctex"]
+
+[params]
+
+compress/mode=2
+compress/high_quality=false
+compress/lossy_quality=0.7
+compress/uastc_level=0
+compress/rdo_quality_loss=0.0
+compress/hdr_compression=1
+compress/normal_map=0
+compress/channel_pack=0
+mipmaps/generate=false
+mipmaps/limit=-1
+roughness/mode=0
+roughness/src_normal=""
+process/channel_remap/red=0
+process/channel_remap/green=1
+process/channel_remap/blue=2
+process/channel_remap/alpha=3
+process/fix_alpha_border=true
+process/premult_alpha=false
+process/normal_map_invert_y=false
+process/hdr_as_srgb=false
+process/hdr_clamp_exposure=false
+process/size_limit=0
+detect_3d/compress_to=0

world/generation/chunks/assets/chunk_0038_dirt.png.import

@@ -0,0 +1,45 @@
+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://cvffkp5rc3xnq"
+path.s3tc="res://.godot/imported/chunk_0038_dirt.png-523fbe5835e3869864352e6e698e49e3.s3tc.ctex"
+path.etc2="res://.godot/imported/chunk_0038_dirt.png-523fbe5835e3869864352e6e698e49e3.etc2.ctex"
+metadata={
+"imported_formats": ["s3tc_bptc", "etc2_astc"],
+"vram_texture": true
+}
+generator_parameters={
+"md5": "07d90b3c46a4c3d0c172bed143dc9436"
+}
+
+[deps]
+
+source_file="res://world/generation/chunks/assets/chunk_0038_dirt.png"
+dest_files=["res://.godot/imported/chunk_0038_dirt.png-523fbe5835e3869864352e6e698e49e3.s3tc.ctex", "res://.godot/imported/chunk_0038_dirt.png-523fbe5835e3869864352e6e698e49e3.etc2.ctex"]
+
+[params]
+
+compress/mode=2
+compress/high_quality=false
+compress/lossy_quality=0.7
+compress/uastc_level=0
+compress/rdo_quality_loss=0.0
+compress/hdr_compression=1
+compress/normal_map=0
+compress/channel_pack=0
+mipmaps/generate=false
+mipmaps/limit=-1
+roughness/mode=0
+roughness/src_normal=""
+process/channel_remap/red=0
+process/channel_remap/green=1
+process/channel_remap/blue=2
+process/channel_remap/alpha=3
+process/fix_alpha_border=true
+process/premult_alpha=false
+process/normal_map_invert_y=false
+process/hdr_as_srgb=false
+process/hdr_clamp_exposure=false
+process/size_limit=0
+detect_3d/compress_to=0

world/generation/chunks/assets/chunk_0038_grass_lite.png.import

@@ -0,0 +1,45 @@
+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://b231ivhqjd1n5"
+path.s3tc="res://.godot/imported/chunk_0038_grass_lite.png-0784255d8b50ad328314d6b349ab3d43.s3tc.ctex"
+path.etc2="res://.godot/imported/chunk_0038_grass_lite.png-0784255d8b50ad328314d6b349ab3d43.etc2.ctex"
+metadata={
+"imported_formats": ["s3tc_bptc", "etc2_astc"],
+"vram_texture": true
+}
+generator_parameters={
+"md5": "4dc1ac400d85d9b3e4f43a5af0a38ed4"
+}
+
+[deps]
+
+source_file="res://world/generation/chunks/assets/chunk_0038_grass_lite.png"
+dest_files=["res://.godot/imported/chunk_0038_grass_lite.png-0784255d8b50ad328314d6b349ab3d43.s3tc.ctex", "res://.godot/imported/chunk_0038_grass_lite.png-0784255d8b50ad328314d6b349ab3d43.etc2.ctex"]
+
+[params]
+
+compress/mode=2
+compress/high_quality=false
+compress/lossy_quality=0.7
+compress/uastc_level=0
+compress/rdo_quality_loss=0.0
+compress/hdr_compression=1
+compress/normal_map=0
+compress/channel_pack=0
+mipmaps/generate=false
+mipmaps/limit=-1
+roughness/mode=0
+roughness/src_normal=""
+process/channel_remap/red=0
+process/channel_remap/green=1
+process/channel_remap/blue=2
+process/channel_remap/alpha=3
+process/fix_alpha_border=true
+process/premult_alpha=false
+process/normal_map_invert_y=false
+process/hdr_as_srgb=false
+process/hdr_clamp_exposure=false
+process/size_limit=0
+detect_3d/compress_to=0

world/generation/chunks/definitions/chunk_0038.tres

@@ -0,0 +1,23 @@
+[gd_resource type="Resource" script_class="TerrainChunkDefinition" load_steps=3 format=3]
+
+[ext_resource type="Script" path="res://world/generation/terrain_chunk_definition.gd" id="1_definition"]
+[ext_resource type="PackedScene" path="res://world/generation/chunks/assets/chunk_0038.glb" id="2_scene"]
+
+[resource]
+script = ExtResource("1_definition")
+stable_id = &"chunk_0038"
+label = "river stepping-stone edge"
+packed_scene = ExtResource("2_scene")
+primary_mesh_name = &"chunk_0038"
+participates_in_base_solver = false
+selection_weight = 0.1
+maximum_placements = 2
+tags = PackedStringArray("land", "walkable", "grass", "flat", "spawn_safe", "fresh_water", "river", "river_border", "river_bridge", "stepping_stones", "flowing")
+allowed_neighbor_tags = PackedStringArray("grass")
+north_allowed_neighbor_tags = PackedStringArray("grass")
+north_surface_tags = PackedStringArray("grass")
+preferred_neighbor_tags = PackedStringArray("grass", "fresh_water", "river")
+must_be_interior = true
+water_inlet_edges = 14
+water_outlet_edges = 14
+water_surface_polygon = PackedVector2Array(-5, -4.619923, -3.897078, -4.512341, -2.980631, -4.203938, -2.250611, -4.038979, -0.609729, -4.132217, 0.90103, -4.286418, 1.924084, -4.17525, 2.678182, -4.067667, 3.604412, -4.189594, 4.269883, -4.408344, 5, -4.619923, 5, 5, -5, 5)

world/generation/chunks/terrain_chunk_catalog.tres

@@ -1,4 +1,4 @@
-[gd_resource type="Resource" script_class="TerrainChunkCatalog" load_steps=47 format=3]
+[gd_resource type="Resource" script_class="TerrainChunkCatalog" load_steps=48 format=3]
 
 [ext_resource type="Script" path="res://world/generation/terrain_chunk_catalog.gd" id="1_catalog"]
 [ext_resource type="Resource" path="res://world/generation/chunks/definitions/chunk_0000.tres" id="2_grass"]
@@ -42,6 +42,7 @@
 [ext_resource type="Resource" path="res://world/generation/chunks/definitions/chunk_0035.tres" id="44_river_bend_a"]
 [ext_resource type="Resource" path="res://world/generation/chunks/definitions/chunk_0036.tres" id="45_river_bend_d"]
 [ext_resource type="Resource" path="res://world/generation/chunks/definitions/chunk_0037.tres" id="46_lake_edge_variant"]
+[ext_resource type="Resource" path="res://world/generation/chunks/definitions/chunk_0038.tres" id="47_river_stone_bridge"]
 [ext_resource type="Resource" path="res://world/generation/chunks/definitions/chunk_9999.tres" id="21_cliff_sea_transition_right"]
 [ext_resource type="Resource" path="res://world/generation/chunks/definitions/chunk_9998.tres" id="22_cliff_sea_transition_left"]
 [ext_resource type="Resource" path="res://world/generation/chunks/definitions/chunk_9997.tres" id="23_cliff_beach_transition_right"]
@@ -50,4 +51,4 @@
 [resource]
 script = ExtResource("1_catalog")
 chunk_size = 10.0
-definitions = Array[ExtResource("7_definition_script")]([ExtResource("2_grass"), ExtResource("3_sand"), ExtResource("4_beach"), ExtResource("5_stream"), ExtResource("20_stream_variant"), ExtResource("6_pond"), ExtResource("25_lake_edge"), ExtResource("46_lake_edge_variant"), ExtResource("26_lake_corner"), ExtResource("27_lake_fill"), ExtResource("28_lake_diagonal"), ExtResource("29_lake_narrow"), ExtResource("30_lake_regular_to_narrow"), ExtResource("31_lake_narrow_to_regular"), ExtResource("32_river_edge"), ExtResource("33_river_edge_variant"), ExtResource("38_river_source_right"), ExtResource("39_river_source_left"), ExtResource("40_river_outlet_right"), ExtResource("41_river_outlet_left"), ExtResource("42_river_bend_c"), ExtResource("43_river_bend_b"), ExtResource("44_river_bend_a"), ExtResource("45_river_bend_d"), ExtResource("34_river_cap"), ExtResource("9_grass_ocean_edge"), ExtResource("10_grass_beach_transition"), ExtResource("11_grass_ocean_corner"), ExtResource("12_beach_ocean_corner"), ExtResource("17_grass_sand_diagonal"), ExtResource("13_cliff_top"), ExtResource("14_cliff_corner"), ExtResource("15_cliff_edge"), ExtResource("16_cliff_ramp"), ExtResource("35_cliff_third_tier_edge"), ExtResource("36_cliff_third_tier_corner"), ExtResource("37_cliff_third_tier_top"), ExtResource("18_cliff_sea_edge"), ExtResource("19_cliff_sea_corner"), ExtResource("21_cliff_sea_transition_right"), ExtResource("22_cliff_sea_transition_left"), ExtResource("23_cliff_beach_transition_right"), ExtResource("24_cliff_beach_transition_left"), ExtResource("8_spawn")])
+definitions = Array[ExtResource("7_definition_script")]([ExtResource("2_grass"), ExtResource("3_sand"), ExtResource("4_beach"), ExtResource("5_stream"), ExtResource("20_stream_variant"), ExtResource("6_pond"), ExtResource("25_lake_edge"), ExtResource("46_lake_edge_variant"), ExtResource("26_lake_corner"), ExtResource("27_lake_fill"), ExtResource("28_lake_diagonal"), ExtResource("29_lake_narrow"), ExtResource("30_lake_regular_to_narrow"), ExtResource("31_lake_narrow_to_regular"), ExtResource("32_river_edge"), ExtResource("33_river_edge_variant"), ExtResource("47_river_stone_bridge"), ExtResource("38_river_source_right"), ExtResource("39_river_source_left"), ExtResource("40_river_outlet_right"), ExtResource("41_river_outlet_left"), ExtResource("42_river_bend_c"), ExtResource("43_river_bend_b"), ExtResource("44_river_bend_a"), ExtResource("45_river_bend_d"), ExtResource("34_river_cap"), ExtResource("9_grass_ocean_edge"), ExtResource("10_grass_beach_transition"), ExtResource("11_grass_ocean_corner"), ExtResource("12_beach_ocean_corner"), ExtResource("17_grass_sand_diagonal"), ExtResource("13_cliff_top"), ExtResource("14_cliff_corner"), ExtResource("15_cliff_edge"), ExtResource("16_cliff_ramp"), ExtResource("35_cliff_third_tier_edge"), ExtResource("36_cliff_third_tier_corner"), ExtResource("37_cliff_third_tier_top"), ExtResource("18_cliff_sea_edge"), ExtResource("19_cliff_sea_corner"), ExtResource("21_cliff_sea_transition_right"), ExtResource("22_cliff_sea_transition_left"), ExtResource("23_cliff_beach_transition_right"), ExtResource("24_cliff_beach_transition_left"), ExtResource("8_spawn")])

world/generation/generated_world_region.gd

@@ -19,6 +19,9 @@ const SALT_WATER_MATERIAL: Material = preload(
 const FRESH_WATER_MATERIAL: Material = preload(
 	"res://world/materials/stylized_water_fresh.tres"
 )
+const GENERATED_TERRAIN_DIRT_MATERIAL: Material = preload(
+	"res://world/materials/generated_terrain_dirt.tres"
+)
 const GENERATED_POND_POOL: FishPool = preload(
 	"res://fish/pools/generated_pond_pool.tres"
 )
@@ -32,12 +35,26 @@ const OCEAN_POOL: FishPool = preload(
 	"res://fish/pools/starter_ocean_pool.tres"
 )
 const WATER_HEIGHT := -0.25
+const GENERATED_FRESH_WATER_BED_HEIGHT := -2.85
 const PROP_EDGE_MARGIN := 2.2
 const PROP_PLACEMENT_ATTEMPTS := 12
 const PROP_CLUSTER_PLACEMENT_ATTEMPTS := 10
 const PROP_MINIMUM_GROUND_CLEARANCE := 0.05
+const PROP_MAXIMUM_SUPPORT_HEIGHT_DIFFERENCE := 0.35
 const PROP_CHANCE_SCALE := 10000
 const PROP_SELECTION_WEIGHT_SCALE := 1000
+const PROP_SURFACE_SAMPLE_DIRECTIONS: Array[Vector2] = [
+	Vector2(1.0, 0.0),
+	Vector2(0.70710678, 0.70710678),
+	Vector2(0.0, 1.0),
+	Vector2(-0.70710678, 0.70710678),
+	Vector2(-1.0, 0.0),
+	Vector2(-0.70710678, -0.70710678),
+	Vector2(0.0, -1.0),
+	Vector2(0.70710678, -0.70710678),
+]
+const GRASS_PROP_SURFACE_MATERIALS: Array[StringName] = [&"grass_lite"]
+const SAND_PROP_SURFACE_MATERIALS: Array[StringName] = [&"sand"]
 const PROCEDURAL_PROP_GROUPS: Array[StringName] = [
 	&"grass_tree",
 	&"grass_detail",
@@ -185,7 +202,16 @@ func _on_generation_completed(summary: Dictionary) -> void:
 	_placed_group_coordinates.clear()
 	var random := RandomNumberGenerator.new()
 	random.seed = _current_seed ^ 0x5EED71
-	var terrain_triangles := _terrain_surface_triangles()
+	var grass_surface_triangles_by_coordinate := (
+		_terrain_surface_triangles_by_coordinate(
+			GRASS_PROP_SURFACE_MATERIALS,
+		)
+	)
+	var sand_surface_triangles_by_coordinate := (
+		_terrain_surface_triangles_by_coordinate(
+			SAND_PROP_SURFACE_MATERIALS,
+		)
+	)
 	var biomes: Array[TerrainBiomeDefinition] = []
 	if biome_catalog != null:
 		biomes.assign(biome_catalog.definitions)
@@ -250,6 +276,14 @@ func _on_generation_completed(summary: Dictionary) -> void:
 					"tags",
 					PackedStringArray(),
 				)
+				var terrain_triangles := _surface_triangles_for_coordinate(
+					(
+						sand_surface_triangles_by_coordinate
+						if group == &"sand_tree"
+						else grass_surface_triangles_by_coordinate
+					),
+					coordinate,
+				)
 				var definitions := _spawn_distance_eligible_definitions(
 					_prop_definitions_for(rule, tags),
 					coordinate,
@@ -287,7 +321,8 @@ func _on_generation_completed(summary: Dictionary) -> void:
 		eligible_records,
 		group_counts,
 		random,
-		terrain_triangles,
+		grass_surface_triangles_by_coordinate,
+		sand_surface_triangles_by_coordinate,
 	)
 	_place_spawn_amenities(spawn_position)
 	_configure_fresh_water(records)
@@ -406,6 +441,11 @@ func _configure_fresh_water(records: Array[Dictionary]) -> void:
 			body.surface_polygon = surface_polygon
 		else:
 			body.surface_size = surface_size
+		_add_generated_fresh_water_bed(
+			body,
+			surface_polygon,
+			surface_size,
+		)
 		body.visual_surface_enabled = false
 		body.water_material = _fresh_water_material()
 		body.water_type = WaterType.Type.FRESH_WATER
@@ -418,6 +458,59 @@ func _configure_fresh_water(records: Array[Dictionary]) -> void:
 		body.selection_priority = 10
 
 
+func _add_generated_fresh_water_bed(
+	body: WaterBodyAuthoring,
+	surface_polygon: PackedVector2Array,
+	surface_size: Vector2,
+) -> void:
+	var polygon := surface_polygon
+	if polygon.size() < 3:
+		var half_size := surface_size * 0.5
+		polygon = PackedVector2Array([
+			Vector2(-half_size.x, -half_size.y),
+			Vector2(half_size.x, -half_size.y),
+			Vector2(half_size.x, half_size.y),
+			Vector2(-half_size.x, half_size.y),
+		])
+	var triangle_indices := Geometry2D.triangulate_polygon(polygon)
+	if triangle_indices.size() < 3:
+		return
+	var vertices := PackedVector3Array()
+	var normals := PackedVector3Array()
+	for offset: int in range(0, triangle_indices.size(), 3):
+		var triangle := PackedVector3Array()
+		for point_offset: int in 3:
+			var point := polygon[triangle_indices[offset + point_offset]]
+			triangle.append(Vector3(point.x, 0.0, point.y))
+		if (
+			(triangle[1] - triangle[0]).cross(
+				triangle[2] - triangle[0]
+			).dot(Vector3.UP) < 0.0
+		):
+			var swap := triangle[1]
+			triangle[1] = triangle[2]
+			triangle[2] = swap
+		vertices.append_array(triangle)
+		normals.append_array(PackedVector3Array([
+			Vector3.UP,
+			Vector3.UP,
+			Vector3.UP,
+		]))
+	var arrays := []
+	arrays.resize(Mesh.ARRAY_MAX)
+	arrays[Mesh.ARRAY_VERTEX] = vertices
+	arrays[Mesh.ARRAY_NORMAL] = normals
+	var mesh := ArrayMesh.new()
+	mesh.add_surface_from_arrays(Mesh.PRIMITIVE_TRIANGLES, arrays)
+	var bed := MeshInstance3D.new()
+	bed.name = "GeneratedBed"
+	bed.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
+	bed.position.y = GENERATED_FRESH_WATER_BED_HEIGHT - WATER_HEIGHT
+	bed.material_override = GENERATED_TERRAIN_DIRT_MATERIAL
+	bed.mesh = mesh
+	body.add_child(bed)
+
+
 func _fresh_water_location_tags(tags: PackedStringArray) -> Array[StringName]:
 	var result: Array[StringName] = [&"generated_fresh_water"]
 	if "pond" in tags:
@@ -524,6 +617,7 @@ func _add_prop(
 	)
 	var primary_scale := visual_scales[0]
 	var scaled_clearance := definition.clearance_radius * primary_scale
+	var support_radius := clampf(scaled_clearance * 0.35, 0.25, 0.65)
 	var placement := Vector3.ZERO
 	var found_surface := false
 	for _attempt: int in PROP_PLACEMENT_ATTEMPTS:
@@ -541,6 +635,12 @@ func _add_prop(
 			surface_height > -INF
 			and surface_height
 			> WATER_HEIGHT + PROP_MINIMUM_GROUND_CLEARANCE
+			and _surface_supports_prop_footprint(
+				placement,
+				surface_height,
+				support_radius,
+				terrain_triangles,
+			)
 			and _has_prop_clearance(
 				placement,
 				scaled_clearance,
@@ -572,6 +672,11 @@ func _add_prop(
 	for member_index: int in range(1, cluster_size):
 		var member_scale := visual_scales[member_index]
 		var member_clearance := definition.clearance_radius * member_scale
+		var member_support_radius := clampf(
+			member_clearance * 0.35,
+			0.25,
+			0.65,
+		)
 		for _attempt: int in PROP_CLUSTER_PLACEMENT_ATTEMPTS:
 			var sector_angle := (
 				cluster_angle
@@ -598,6 +703,12 @@ func _add_prop(
 			)
 			if (
 				surface_height <= WATER_HEIGHT + PROP_MINIMUM_GROUND_CLEARANCE
+				or not _surface_supports_prop_footprint(
+					candidate,
+					surface_height,
+					member_support_radius,
+					terrain_triangles,
+				)
 				or not _has_prop_clearance(candidate, member_clearance)
 			):
 				continue
@@ -959,7 +1070,8 @@ func _ensure_minimum_props(
 	eligible_records: Dictionary[StringName, Array],
 	group_counts: Dictionary[StringName, int],
 	random: RandomNumberGenerator,
-	terrain_triangles: Array[PackedVector3Array],
+	grass_surface_triangles_by_coordinate: Dictionary[Vector2i, Array],
+	sand_surface_triangles_by_coordinate: Dictionary[Vector2i, Array],
 ) -> void:
 	if biome_catalog == null:
 		return
@@ -993,6 +1105,14 @@ func _ensure_minimum_props(
 					"coordinate",
 					Vector2i.ZERO,
 				)
+				var terrain_triangles := _surface_triangles_for_coordinate(
+					(
+						sand_surface_triangles_by_coordinate
+						if group == &"sand_tree"
+						else grass_surface_triangles_by_coordinate
+					),
+					coordinate,
+				)
 				var definitions := _spawn_distance_eligible_definitions(
 					_prop_definitions_for(rule, tags),
 					coordinate,
@@ -1101,12 +1221,26 @@ func _apply_material_variant_to_meshes(
 		)
 
 
-func _terrain_surface_triangles() -> Array[PackedVector3Array]:
-	var triangles: Array[PackedVector3Array] = []
+func _terrain_surface_triangles_by_coordinate(
+	material_names: Array[StringName],
+) -> Dictionary[Vector2i, Array]:
+	var triangles_by_coordinate: Dictionary[Vector2i, Array] = {}
+	if material_names.is_empty():
+		return triangles_by_coordinate
 	for mesh_instance: MeshInstance3D in _generator.get_primary_terrain_meshes():
 		if mesh_instance.mesh == null:
 			continue
+		var coordinate := _terrain_coordinate_for(mesh_instance)
+		if coordinate.x < 0 or coordinate.y < 0:
+			continue
+		var triangles: Array[PackedVector3Array] = []
 		for surface_index: int in mesh_instance.mesh.get_surface_count():
+			var material := mesh_instance.get_active_material(surface_index)
+			if (
+				material == null
+				or StringName(material.resource_name) not in material_names
+			):
+				continue
 			_append_surface_triangles(
 				triangles,
 				mesh_instance,
@@ -1114,6 +1248,35 @@ func _terrain_surface_triangles() -> Array[PackedVector3Array]:
 				-INF,
 				0.35,
 			)
+		if triangles.is_empty():
+			continue
+		var coordinate_triangles: Array = triangles_by_coordinate.get(
+			coordinate,
+			[],
+		)
+		coordinate_triangles.append_array(triangles)
+		triangles_by_coordinate[coordinate] = coordinate_triangles
+	return triangles_by_coordinate
+
+
+func _terrain_coordinate_for(mesh_instance: MeshInstance3D) -> Vector2i:
+	var current: Node = mesh_instance
+	while current != null and current != _generator:
+		if current.has_meta(&"terrain_chunk_coordinate"):
+			return current.get_meta(
+				&"terrain_chunk_coordinate",
+				Vector2i(-1, -1),
+			) as Vector2i
+		current = current.get_parent()
+	return Vector2i(-1, -1)
+
+
+func _surface_triangles_for_coordinate(
+	triangles_by_coordinate: Dictionary[Vector2i, Array],
+	coordinate: Vector2i,
+) -> Array[PackedVector3Array]:
+	var triangles: Array[PackedVector3Array] = []
+	triangles.assign(triangles_by_coordinate.get(coordinate, []))
 	return triangles
 
 
@@ -1139,6 +1302,28 @@ func _surface_height_at(
 	return highest
 
 
+func _surface_supports_prop_footprint(
+	position: Vector3,
+	surface_height: float,
+	radius: float,
+	triangles: Array[PackedVector3Array],
+) -> bool:
+	for direction: Vector2 in PROP_SURFACE_SAMPLE_DIRECTIONS:
+		var sample_position := position + Vector3(
+			direction.x * radius,
+			0.0,
+			direction.y * radius,
+		)
+		var sample_height := _surface_height_at(sample_position, triangles)
+		if (
+			sample_height <= -INF
+			or absf(sample_height - surface_height)
+			> PROP_MAXIMUM_SUPPORT_HEIGHT_DIFFERENCE
+		):
+			return false
+	return true
+
+
 func _add_prop_collision(
 	prop: Node3D,
 	definition: TerrainPropDefinition,

world/generation/terrain_chunk_generator.gd

@@ -64,6 +64,7 @@ const PROJECTED_DIRT_MATERIAL: Material = preload(
 @export var river_feature_enabled := false
 @export var river_edge_chunk_id: StringName = &"chunk_0024"
 @export var river_edge_variant_chunk_id: StringName = &"chunk_0025"
+@export var river_stone_bridge_chunk_id: StringName = &"chunk_0038"
 @export var river_source_right_chunk_id: StringName = &"chunk_0029"
 @export var river_source_left_chunk_id: StringName = &"chunk_0030"
 @export var river_outlet_right_chunk_id: StringName = &"chunk_0031"
@@ -1728,6 +1729,7 @@ func _prepare_river_feature_region(report_no_room_error := true) -> bool:
 	for stable_id: StringName in [
 		river_edge_chunk_id,
 		river_edge_variant_chunk_id,
+		river_stone_bridge_chunk_id,
 		river_source_right_chunk_id,
 		river_source_left_chunk_id,
 		river_outlet_right_chunk_id,
@@ -2190,6 +2192,16 @@ func _build_river_feature_candidate(
 		+ bend_origin.y,
 		2,
 	)
+	var straight_station_count := bend_distance + outlet_distance - 2
+	var bridge_station_index := posmod(
+		generation_seed
+		+ source_coordinates[0].x * 73856093
+		+ source_coordinates[0].y * 19349663
+		+ bend_origin.x * 83492791
+		+ bend_origin.y * 2971215073
+		+ bend_turns * 433494437,
+		straight_station_count,
+	)
 	var station_index := 0
 	for step: int in range(1, bend_distance):
 		var pair: Array[Vector2i] = []
@@ -2200,6 +2212,7 @@ func _build_river_feature_candidate(
 				pair,
 				flow_direction,
 				phase + station_index,
+				station_index == bridge_station_index,
 			)
 		)
 		station_index += 1
@@ -2215,6 +2228,7 @@ func _build_river_feature_candidate(
 				pair,
 				outlet_direction,
 				phase + station_index,
+				station_index == bridge_station_index,
 			)
 		)
 		station_index += 1
@@ -2355,6 +2369,7 @@ func _river_edge_pair_specs(
 	pair: Array[Vector2i],
 	flow_direction: Vector2i,
 	phase: int,
+	use_stone_bridge := false,
 ) -> Array[Dictionary]:
 	var ordered := _river_sorted_pair(pair, flow_direction)
 	if ordered.size() != 2:
@@ -2363,6 +2378,11 @@ func _river_edge_pair_specs(
 		river_edge_chunk_id,
 		river_edge_variant_chunk_id,
 	]
+	if use_stone_bridge:
+		edge_ids.assign([
+			river_stone_bridge_chunk_id,
+			river_stone_bridge_chunk_id,
+		])
 	var first_index := posmod(phase, edge_ids.size())
 	var first_turns := 0 if flow_direction.x != 0 else 1
 	var second_turns := 2 if flow_direction.x != 0 else 3

world/materials/terrain_surface_projection.gdshader

@@ -1,7 +1,7 @@
 shader_type spatial;
 render_mode cull_back;
 
-uniform sampler2D albedo_texture : source_color, repeat_enable, filter_nearest;
+uniform sampler2D albedo_texture : source_color, repeat_enable, filter_nearest_mipmap;
 uniform vec4 albedo_tint : source_color = vec4(1.0);
 uniform float tile_world_size : hint_range(0.1, 20.0, 0.05) = 2.5;
 uniform float blend_sharpness : hint_range(1.0, 16.0, 0.25) = 6.0;