Vertical subdivision + calculation for both dims

2 files changed, 10 insertions, 3 deletions

diff --git a/game/src/GameSession/MapView.gd b/game/src/GameSession/MapView.gd
index e74ea59..1b04097 100644
--- a/game/src/GameSession/MapView.gd
+++ b/game/src/GameSession/MapView.gd
@@ -13,6 +13,7 @@ const _action_drag : StringName = &"map_drag"
 const _action_click : StringName = &"map_click"
 
 const _shader_param_province_index : StringName = &"province_index_tex"
+const _shader_param_province_index_subdivisions : StringName = &"province_index_subdivisions"
 const _shader_param_province_colour : StringName = &"province_colour_tex"
 const _shader_param_hover_index : StringName = &"hover_index"
 const _shader_param_selected_index : StringName = &"selected_index"
@@ -86,6 +87,10 @@ func _ready():
 		push_error("Failed to generate province index texture array!")
 		return
 	_map_shader_material.set_shader_parameter(_shader_param_province_index, province_index_texture)
+	var subdivisions := GameSingleton.get_province_index_image_subdivisions()
+	if subdivisions.x < 1 or subdivisions.y < 1:
+		push_error("Invalid province index image subdivision: ", subdivisions.x, "x", subdivisions.y)
+	_map_shader_material.set_shader_parameter(_shader_param_province_index_subdivisions, Vector2(subdivisions))
 
 	# Province colour texture
 	_map_province_colour_image = GameSingleton.get_province_colour_image()
diff --git a/game/src/GameSession/TerrainMap.gdshader b/game/src/GameSession/TerrainMap.gdshader
index 305a34b..f80d6bd 100644
--- a/game/src/GameSession/TerrainMap.gdshader
+++ b/game/src/GameSession/TerrainMap.gdshader
@@ -6,6 +6,8 @@ render_mode unshaded;
 uniform sampler2D farmlands_tex: source_color, repeat_enable, filter_linear;
 // Province index texture
 uniform sampler2DArray province_index_tex : source_color, repeat_enable, filter_nearest;
+// Province index subdivisions
+uniform vec2 province_index_subdivisions;
 // Province colour texture
 uniform sampler2D province_colour_tex: source_color, repeat_enable, filter_nearest;
 // Index of the mouse over the map mesh
@@ -19,9 +21,9 @@ uvec2 vec2_to_uvec2(vec2 v) {
 	return uvec2(v * 255.0);
 }
 uvec2 read_uvec2(vec2 uv) {
-	float width_divisions = float(textureSize(province_index_tex, 0).z);
-	uv.x *= width_divisions;
-	float idx = mod(floor(uv.x),  width_divisions);
+	uv *= province_index_subdivisions;
+	vec2 subdivision_coords = mod(floor(uv),  province_index_subdivisions);
+	float idx = subdivision_coords.x + subdivision_coords.y * province_index_subdivisions.x;
 	return vec2_to_uvec2(texture(province_index_tex, vec3(uv, idx)).rg);
 }
 uint uvec2_to_uint(uvec2 v) {