1 files changed, 18 insertions, 0 deletions
diff --git a/game/src/GameSession/ProvinceIndexSampler.gdshaderinc b/game/src/GameSession/ProvinceIndexSampler.gdshaderinc
new file mode 100644
index 0000000..65f73d8
--- /dev/null
+++ b/game/src/GameSession/ProvinceIndexSampler.gdshaderinc
@@ -0,0 +1,18 @@
+
+// Province shape texture
+uniform sampler2DArray province_shape_tex : repeat_enable, filter_nearest;
+// Province shape subdivisions
+uniform vec2 province_shape_subdivisions;
+
+uvec3 vec3_to_uvec3(vec3 v) {
+	return uvec3(v * 255.0);
+}
+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);
+}
+uint uvec2_to_uint(uvec2 v) {
+	return (v.y << 8u) | v.x;
+}