Add water levels proper

Changelog:
- Fill only a range of reachable tiles instead
- Tweak fill complete check
    - Count tiles filled, if zero: complete
- Allow multiple runner to fill without breaking the game

scenes/engine/EC/EC.h

@@ -160,6 +160,7 @@ typedef struct _CWaterRunner {
     int32_t current_tile;
     int32_t target_tile;
     int32_t fill_idx;
+    int16_t fill_range[2];
     uint8_t movement_delay;
     int16_t counter;
 }CWaterRunner_t;

scenes/water_flow.c

@@ -182,9 +182,6 @@ void update_water_runner_system(Scene_t* scene)
                     p_crunner->bfs_tilemap.tilemap[i].from = -1;
                     p_crunner->bfs_tilemap.tilemap[i].reachable = false;
                 }
-                p_crunner->state = BFS_START;
-                // Want the fallthough
-            case BFS_START:
                 p_crunner->state = LOWEST_POINT_SEARCH;
                 // Want the fallthough
             case LOWEST_POINT_SEARCH:
@@ -232,7 +229,7 @@ void update_water_runner_system(Scene_t* scene)
             {
                 if (tilemap.tiles[p_crunner->current_tile].water_level == tilemap.max_water_level)
                 {
-                    p_crunner->state = FILL_COMPLETE;
+                    p_crunner->state = BFS_RESET;
                     break;
                 }
                 int start_tile =
@@ -246,19 +243,29 @@ void update_water_runner_system(Scene_t* scene)
                 int32_t lowest_tile = p_crunner->current_tile;
                 runner_BFS(&tilemap, p_crunner, &lowest_tile, p_crunner->current_tile);
 
-                p_crunner->counter = 0;
                 for (int i = 0; i < p_crunner->bfs_tilemap.width; ++i)
                 {
-                    Tile_t* curr_tile = tilemap.tiles + start_tile + i;
                     if (
                         p_crunner->bfs_tilemap.tilemap[start_tile + i].reachable
-                        && curr_tile->water_level < tilemap.max_water_level
                     )
                     {
-                        p_crunner->counter++;
+                        p_crunner->fill_range[0] = i;
+                        break;
                     }
                 }
-                p_crunner->fill_idx = 0;
+                for (int i = p_crunner->bfs_tilemap.width - 1; i >= 0; --i)
+                {
+                    if (
+                        p_crunner->bfs_tilemap.tilemap[start_tile + i].reachable
+                    )
+                    {
+                        p_crunner->fill_range[1] = i;
+                        break;
+                    }
+                }
+
+                p_crunner->fill_idx = p_crunner->fill_range[0];
+                p_crunner->counter = 0;
                 p_crunner->state = SCANLINE_FILL;
             }
             break;
@@ -272,24 +279,30 @@ void update_water_runner_system(Scene_t* scene)
                     Tile_t* curr_tile = tilemap.tiles + curr_idx;
                     if (
                         p_crunner->bfs_tilemap.tilemap[curr_idx].reachable
-                        && curr_tile->water_level < tilemap.max_water_level
                     )
                     {
-                        curr_tile->water_level++;
-                        if (curr_tile->water_level == tilemap.max_water_level)
+                        if (curr_tile->water_level < tilemap.max_water_level)
                         {
-                            p_crunner->counter--;
+                            curr_tile->water_level++;
+                        }
+                        if (curr_tile->water_level != tilemap.max_water_level)
+                        {
+                            p_crunner->counter++;
                         }
                     }
 
-                    if (p_crunner->counter == 0)
-                    {
-                        p_crunner->state = BFS_RESET;
-                        break;
-                    }
 
                     p_crunner->fill_idx++;
-                    p_crunner->fill_idx %= p_crunner->bfs_tilemap.width;
+                    if (p_crunner->fill_idx > p_crunner->fill_range[1])
+                    {
+                        if (p_crunner->counter == 0)
+                        {
+                            p_crunner->state = BFS_RESET;
+                            break;
+                        }
+                        p_crunner->counter = 0;
+                        p_crunner->fill_idx = p_crunner->fill_range[0];
+                    }
                 }
             }
             break;

water_test.c

@@ -55,11 +55,18 @@ static void level_scene_render_func(Scene_t* scene)
                 DrawRectangle(x, y, TILE_SIZE, TILE_SIZE, BLACK);
             }
 
-            if (tilemap.tiles[i].water_level > 0)
+            //if (tilemap.tiles[i].water_level > 0)
             {
+                float water_height = tilemap.tiles[i].water_level * 1.0f / tilemap.max_water_level;
                 // Draw water tile
                 Color water_colour = ColorAlpha(BLUE, 0.5);
-                DrawRectangle(x, y, TILE_SIZE, TILE_SIZE, water_colour);
+                DrawRectangle(
+                    x,
+                    y + (1.0f - water_height) * TILE_SIZE,
+                    TILE_SIZE,
+                    water_height * TILE_SIZE,
+                    water_colour
+                );
             }
         }
 
@@ -355,7 +362,7 @@ int main(void)
     scene.data.tilemap.width = DEFAULT_MAP_WIDTH;
     scene.data.tilemap.height = DEFAULT_MAP_HEIGHT;
     scene.data.tilemap.tile_size = TILE_SIZE;
-    scene.data.tilemap.max_water_level = 1;
+    scene.data.tilemap.max_water_level = 4;
     scene.data.tilemap.n_tiles = scene.data.tilemap.width * scene.data.tilemap.height;
     assert(scene.data.tilemap.n_tiles <= MAX_N_TILES);
     scene.data.tilemap.tiles = all_tiles;