Find, filter and outline regions

diff --git a/src/core/game.rs b/src/core/game.rs
index 6c04969..125bd1a 100644 (file)
--- a/src/core/game.rs
+++ b/src/core/game.rs
@@ -58,7 +58,7 @@ impl AppState for GameState {
                return Some(StateChange::Push(Box::new(ActiveState::new((800, 600)))))
             }
            Event::KeyDown { keycode: Some(Keycode::Space), .. } => {
-               self.world.level.regenerate();
+               self.world.level = Level::new(self.world.level.gravity);
            }
            Event::KeyDown { keycode: Some(Keycode::KpPlus), .. } => {
                self.world.level.increase_iteration();

diff --git a/src/core/level.rs b/src/core/level.rs
index c3f4aae..4937551 100644 (file)
--- a/src/core/level.rs
+++ b/src/core/level.rs
@@ -12,31 +12,46 @@ pub struct Level {
     pub gravity: Point2D<f64>,
     pub grid: Grid,
     iterations: u8,
+    walls: Vec<Vec<Point2D<isize>>>,
 }
 
 impl Level {
     pub fn new(gravity: Point2D<f64>) -> Self {
-       Level { gravity, grid: Grid::generate(10), iterations: 10 }
+       let mut lvl = Level { gravity, grid: Grid::generate(10), iterations: 10, walls: vec!() };
+       lvl.filter_regions();
+       lvl
     }
 
-    pub fn regenerate(&mut self) {
+    fn generate(&mut self) {
        self.grid = Grid::generate(self.iterations);
     }
 
     pub fn increase_iteration(&mut self) {
        self.iterations += 1;
-       self.regenerate();
+       self.generate();
        println!("iterate {} time(s)", self.iterations);
     }
 
     pub fn decrease_iteration(&mut self) {
        self.iterations -= 1;
-       self.regenerate();
+       self.generate();
        println!("iterate {} time(s)", self.iterations);
     }
 
     pub fn filter_regions(&mut self) {
        self.grid.filter_regions();
+       let mut walls = vec!();
+       for mut r in self.grid.find_regions() {
+           if r.value {
+               let mut outline = r.outline(self.grid.cell_size);
+               for i in 2..(outline.len() - 2) {
+//                 outline[i] = (outline[i - 1] + outline[i] + outline[i + 1]) / 3;
+                   outline[i] = (outline[i - 2] + outline[i - 1] + outline[i] + outline[i + 1] + outline[i + 2]) / 5;
+               }
+               walls.push(outline);
+           }
+       }
+       self.walls = walls;
     }
 
     pub fn render(&mut self, renderer: &mut Renderer, _sprites: &SpriteManager) {
@@ -49,11 +64,21 @@ impl Level {
                }
            }
        }
+
+       let off = (size / 2) as i32;
+       for wall in &self.walls {
+           for w in wall.windows(2) {
+               renderer.draw_line((w[0].x as i32 + off, w[0].y as i32 + off), (w[1].x as i32 + off, w[1].y as i32 + off), (255, 255, 0));
+           }
+           let last = wall.len() - 1;
+           renderer.draw_line((wall[0].x as i32 + off, wall[0].y as i32 + off), (wall[last].x as i32 + off, wall[last].y as i32 + off), (255, 255, 0));
+       }
     }
 }
 
 ////////// GRID ////////////////////////////////////////////////////////////////
 
+
 #[derive(Default)]
 pub struct Grid {
     pub width: usize,
@@ -265,3 +290,111 @@ struct Region {
     value: bool,
     cells: Vec<(usize, usize)>,
 }
+
+impl Region {
+    fn enclosing_rect(&self) -> (usize, usize, usize, usize) {
+       let mut min = (usize::MAX, usize::MAX);
+       let mut max = (0, 0);
+       for c in &self.cells {
+           if      c.0 < min.0 { min.0 = c.0; }
+           else if c.0 > max.0 { max.0 = c.0; }
+           if      c.1 < min.1 { min.1 = c.1; }
+           else if c.1 > max.1 { max.1 = c.1; }
+       }
+       (min.0, min.1, 1 + max.0 - min.0, 1 + max.1 - min.1)
+    }
+
+    pub fn outline(&mut self, scale: usize) -> Vec<Point2D<isize>> {
+       let rect = self.enclosing_rect();
+       let (ox, oy, w, h) = rect;
+       let grid = self.grid(&rect);
+       let mut marked = vec!(vec!(false; h); w);
+       let mut outline = vec!();
+
+       let (mut p, mut dir) = self.find_first_point_of_outline(&rect, &grid);
+//     println!("starting at {:?} with dir {:?}", p, dir);
+       marked[p.x as usize][p.y as usize] = true;
+       loop {
+           outline.push((p + (ox as isize, oy as isize)) * scale as isize);
+           let result = self.find_next_point_of_outline(&grid, p, dir);
+           p = result.0;
+           dir = result.1;
+//         println!("next at {:?} with dir {:?}", p, dir);
+           if marked[p.x as usize][p.y as usize] {
+               // we're back at the beginning
+               break;
+           }
+           marked[p.x as usize][p.y as usize] = true;
+       }
+
+       outline
+    }
+
+    fn grid(&self, rect: &(usize, usize, usize, usize)) -> Vec<Vec<bool>> {
+       let (x, y, w, h) = rect;
+       let mut grid = vec!(vec!(false; *h); *w);
+       for c in &self.cells {
+           grid[c.0 - x][c.1 - y] = true;
+       }
+       grid
+    }
+
+    fn find_first_point_of_outline(&self, rect: &(usize, usize, usize, usize), grid: &Vec<Vec<bool>>) -> (Point2D<isize>, Point2D<isize>) {
+       let (ox, oy, w, h) = rect;
+       let is_outer_wall = (ox, oy) == (&0, &0); // we know this is always the outer wall of the level
+       for x in 0..*w {
+           for y in 0..*h {
+               if is_outer_wall && !grid[x][y] {
+                   return (point!(x as isize, y as isize - 1), point!(0, 1)) // one step back because we're not on a wall tile
+               }
+               else if !is_outer_wall && grid[x][y] {
+                   return (point!(x as isize, y as isize), point!(1, 0))
+               }
+           }
+       }
+       panic!("no wall found!");
+    }
+
+    fn find_next_point_of_outline(&self, grid: &Vec<Vec<bool>>, p: Point2D<isize>, dir: Point2D<isize>) -> (Point2D<isize>, Point2D<isize>) {
+       let left = match dir.into() {
+           (-1, 0) => (0, 1),
+           (0, 1) => (1, 0),
+           (1, 0) => (0, -1),
+           (0, -1) => (-1, 0),
+           _ => (0, 0),
+       };
+       let right = match dir.into() {
+           (0, 1) => (-1, 0),
+           (1, 0) => (0, 1),
+           (0, -1) => (1, 0),
+           (-1, 0) => (0, -1),
+           _ => (0, 0),
+       };
+       if self.check(p + dir, grid) {
+//         println!("{:?} is true", p + dir);
+           if self.check(p + dir + left, grid) {
+//             println!("going left to {:?}", p + dir + left);
+               return (p + dir + left, left.into())
+           } else {
+               return (p + dir, dir)
+           }
+       } else {
+//         println!("{:?} is false", p + dir);
+           if self.check(p + dir + right, grid) {
+//             println!("going right to {:?}", p + dir + right);
+               return (p + dir + right, dir)
+           } else {
+//             println!("going right from p to {:?}", p + right);
+               return (p + right, right.into())
+           }
+       }
+    }
+
+    fn check(&self, p: Point2D<isize>, grid: &Vec<Vec<bool>>) -> bool {
+       if p.x < 0 || p.x >= grid.len() as isize || p.y < 0 || p.y >= grid[0].len() as isize {
+           false
+       } else {
+           grid[p.x as usize][p.y as usize]
+       }
+    }
+}