Striped mapmodes

4 files changed, 38 insertions, 14 deletions

diff --git a/game/src/Game/GameSession/MapControlPanel/Minimap.gd b/game/src/Game/GameSession/MapControlPanel/Minimap.gd
index be65db5..5564821 100644
--- a/game/src/Game/GameSession/MapControlPanel/Minimap.gd
+++ b/game/src/Game/GameSession/MapControlPanel/Minimap.gd
@@ -10,7 +10,7 @@ var _minimap_shader : ShaderMaterial
 var _viewport_points : PackedVector2Array
 
 func _ready():
-	_minimap_texture.custom_minimum_size = Vector2(GameSingleton.get_aspect_ratio(), 1.0) * 150
+	_minimap_texture.custom_minimum_size = Vector2(GameSingleton.get_map_aspect_ratio(), 1.0) * 150
 	var minimap_material := _minimap_texture.get_material()
 	if GameLoader.ShaderManager.set_up_shader(minimap_material, false) != OK:
 		push_error("Failed to set up minimap shader")
diff --git a/game/src/Game/GameSession/MapView.gd b/game/src/Game/GameSession/MapView.gd
index 345ab9e..7093c69 100644
--- a/game/src/Game/GameSession/MapView.gd
+++ b/game/src/Game/GameSession/MapView.gd
@@ -74,7 +74,10 @@ func _ready():
 	# Set map mesh size and get bounds
 	const pixels_per_terrain_tile : float = 32.0
 	_map_shader_material.set_shader_parameter(GameLoader.ShaderManager.param_terrain_tile_factor,
-		float(GameSingleton.get_height()) / pixels_per_terrain_tile)
+		float(GameSingleton.get_map_height()) / pixels_per_terrain_tile)
+	const pixels_per_stripe_tile : float = 16.0
+	_map_shader_material.set_shader_parameter(GameLoader.ShaderManager.param_stripe_tile_factor,
+		float(GameSingleton.get_map_height()) / pixels_per_stripe_tile)
 	var map_mesh_aabb := _map_mesh.get_core_aabb() * _map_mesh_instance.transform
 	_map_mesh_corner = Vector2(
 		min(map_mesh_aabb.position.x, map_mesh_aabb.end.x),
diff --git a/game/src/Game/GameSession/ProvinceIndexSampler.gdshaderinc b/game/src/Game/GameSession/ProvinceIndexSampler.gdshaderinc
index 65f73d8..1adcd95 100644
--- a/game/src/Game/GameSession/ProvinceIndexSampler.gdshaderinc
+++ b/game/src/Game/GameSession/ProvinceIndexSampler.gdshaderinc
@@ -4,15 +4,21 @@ uniform sampler2DArray province_shape_tex : repeat_enable, filter_nearest;
 // Province shape subdivisions
 uniform vec2 province_shape_subdivisions;
 
+// Convert a vector of 3 normalised floats to a vector of 3 unsigned bytes
 uvec3 vec3_to_uvec3(vec3 v) {
 	return uvec3(v * 255.0);
 }
+
+// Create a uint triplet describing the province and terrain data at a map-space UV coordinate:
+// (u, v) -> (province index bottom byte, province index top byte, terrain index byte)
 uvec3 read_uvec3(vec2 uv) {
 	uv *= province_shape_subdivisions;
 	vec2 subdivision_coords = mod(floor(uv),  province_shape_subdivisions);
 	float idx = subdivision_coords.x + subdivision_coords.y * province_shape_subdivisions.x;
 	return vec3_to_uvec3(texture(province_shape_tex, vec3(uv, idx)).rgb);
 }
+
+// Combine a (lower byte, upper byte) uint pair into a single 2-byte uint
 uint uvec2_to_uint(uvec2 v) {
 	return (v.y << 8u) | v.x;
 }
diff --git a/game/src/Game/GameSession/TerrainMap.gdshader b/game/src/Game/GameSession/TerrainMap.gdshader
index 852ccc3..ff8708a 100644
--- a/game/src/Game/GameSession/TerrainMap.gdshader
+++ b/game/src/Game/GameSession/TerrainMap.gdshader
@@ -14,16 +14,29 @@ uniform uint selected_index;
 uniform sampler2DArray terrain_tex: source_color, repeat_enable, filter_linear;
 // The number of times the terrain textures should tile vertically
 uniform float terrain_tile_factor;
+// Map stripe mask texture
+uniform sampler2D stripe_tex: source_color, repeat_enable, filter_nearest;
+// The number of times the stripe texture should tile vertically
+uniform float stripe_tile_factor;
 
 const vec3 highlight_colour = vec3(1.0);
 
-vec3 get_terrain_colour(vec2 uv, vec2 corner, vec2 half_pixel_size, vec2 terrain_uv) {
+vec3 get_terrain_colour(vec2 uv, vec2 corner, vec2 half_pixel_size, vec2 terrain_uv, vec2 stripe_uv) {
 	uvec3 province_data = read_uvec3(fma(corner, half_pixel_size, uv));
-	vec4 province_colour = texelFetch(province_colour_tex, ivec2(province_data.rg), 0);
-	vec3 terrain_colour = texture(terrain_tex, vec3(terrain_uv, float(province_data.b))).rgb;
+	uint province_index = uvec2_to_uint(province_data.rg);
+	uint terrain_index = province_data.b;
+
+	province_data.r *= 2u; // Double "x coordinate" as colours come in (base, stripe) pairs
+	vec4 province_base_colour = texelFetch(province_colour_tex, ivec2(province_data.rg), 0);
+	province_data.r += 1u; // Add 1 to "x coordinate" to move from base to strip colour
+	vec4 province_stripe_colour = texelFetch(province_colour_tex, ivec2(province_data.rg), 0);
+	float stripe = texture(stripe_tex, stripe_uv).b; // Stripe mask value - 0 for base, 1 for stripe
+	vec4 province_colour = mix(province_base_colour, province_stripe_colour, stripe);
+
+	vec3 terrain_colour = texture(terrain_tex, vec3(terrain_uv, float(terrain_index))).rgb;
 	vec3 mixed_colour = mix(terrain_colour, province_colour.rgb, province_colour.a);
-	uint index = uvec2_to_uint(province_data.rg);
-	float mix_val = 0.1 * (float(index == hover_index) + float(index == selected_index));
+
+	float mix_val = 0.1 * (float(province_index == hover_index) + float(province_index == selected_index));
 	return mix(mixed_colour, highlight_colour, mix_val);
 }
 
@@ -32,15 +45,17 @@ vec3 mix_terrain_colour(vec2 uv) {
 	vec2 pixel_offset = fract(fma(uv, map_size, vec2(0.5)));
 	vec2 half_pixel_size = 0.49 / map_size;
 
-	vec2 terrain_uv = uv;
-	terrain_uv.x *= map_size.x / map_size.y;
-	terrain_uv *= terrain_tile_factor;
+	// UV coords adjusted to remove squashing caused by normalisation relative to map dimensions.
+	vec2 unscaled_uv = vec2(uv.x * map_size.x / map_size.y, uv.y);
+
+	vec2 terrain_uv = unscaled_uv * terrain_tile_factor;
+	vec2 stripe_uv = unscaled_uv * stripe_tile_factor;
 
 	return mix(
-		mix(get_terrain_colour(uv, vec2(-1, -1), half_pixel_size, terrain_uv),
-			get_terrain_colour(uv, vec2(+1, -1), half_pixel_size, terrain_uv), pixel_offset.x),
-		mix(get_terrain_colour(uv, vec2(-1, +1), half_pixel_size, terrain_uv),
-			get_terrain_colour(uv, vec2(+1, +1), half_pixel_size, terrain_uv), pixel_offset.x),
+		mix(get_terrain_colour(uv, vec2(-1, -1), half_pixel_size, terrain_uv, stripe_uv),
+			get_terrain_colour(uv, vec2(+1, -1), half_pixel_size, terrain_uv, stripe_uv), pixel_offset.x),
+		mix(get_terrain_colour(uv, vec2(-1, +1), half_pixel_size, terrain_uv, stripe_uv),
+			get_terrain_colour(uv, vec2(+1, +1), half_pixel_size, terrain_uv, stripe_uv), pixel_offset.x),
 			pixel_offset.y);
 }