Working on collisions

assets/levels/level1.txt

@@ -3,13 +3,13 @@
 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
-0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
+0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0
-0 0 0 0 0 0 0 0 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0
+0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0
-0 0 0 0 0 0 0 0 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0
-0 0 0 0 0 0 0 0 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0
 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
+0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0
+0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0
 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
-1 1 1 1 0 0 0 1 1 1 1 1 1 0 0 0 1 1 1 1 1 1 1 1
+1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
-1 1 1 1 0 0 0 1 1 1 1 1 1 0 0 0 1 1 1 1 1 1 1 1
+1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
-1 1 1 1 0 0 0 1 1 1 1 1 1 0 0 0 1 1 1 1 1 1 1 1
+1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

src/engine/map/mod.rs

@@ -402,21 +402,109 @@ impl Map {
     pub fn collides_point(&self, old: Vector2<f32>, new: Vector2<f32>)
         -> Option<(CollisionAxis, Vector2<f32>)> {
 
-        let height = new.y - old.y;
+        let vert = self.collides_point_vertical(old, new);
-        let mut y = (old.y / 16.0).ceil() * 16.0;
+        let horiz = self.collides_point_horizontal(old, new);
+        match (vert, horiz) {
+            (Some(a), Some(b)) => {
+                if (old.x - a.1.x).abs() < (old.x - b.1.x).abs() {
+                    Some(a)
+                } else {
+                    Some(b)
+                }
+            },
+            (Some(a), None) => Some(a),
+            (None, Some(b)) => Some(b),
+            (None, None) => None,
+        }
+    }
 
-        while y < new.y {
+    /// Checks whether the vector (old, new) collides horizontally with an element of the map.
+    ///
+    /// Returns the height of the collision if any.
+    pub fn collides_point_horizontal(&self, old: Vector2<f32>, new: Vector2<f32>)
+        -> Option<(CollisionAxis, Vector2<f32>)> {
 
-            let current_height = y - old.y;
+        let width = new.y - old.y;
-            let x = old.x + (new.x - old.x) * current_height / height;
+
+        if width == 0.0 {
+            return None;
+        }
+
+        let x = if width > 0.0 {
+            (old.x / 16.0).ceil() * 16.0
+        } else {
+            (old.x / 16.0).floor() * 16.0
+        };
+
+        let mut col = (x / 16.0) as isize;
+
+        while (col as f32 * 16.0 - new.x) * width.signum() < 0.0 {
+
+            let current_width = col as f32 * 16.0 - old.x;
+            let y = old.y + (new.y - old.y) * current_width / width;
 
             // Find tile on x, y
             if x > 0.0 && y > 0.0 {
 
                 let row = (y / 16.0) as usize;
+
+                let col = if width > 0.0 {
+                    col
+                } else {
+                    col - 1
+                };
+
+                if let Some((tile, _)) = self.tiles.get((row, col as usize)) {
+                    if tile.from_top {
+                        return Some((CollisionAxis::X, Vector2::new(x, y)));
+                    }
+                }
+
+            }
+
+            col += width.signum() as isize;
+        }
+
+        None
+    }
+
+    /// Checks whether the vector (old, new) collides vertically with an element of the map.
+    ///
+    /// Returns the height of the collision if any.
+    pub fn collides_point_vertical(&self, old: Vector2<f32>, new: Vector2<f32>)
+        -> Option<(CollisionAxis, Vector2<f32>)> {
+
+        let height = new.y - old.y;
+
+        if height == 0.0 {
+            return None;
+        }
+
+        let y = if height > 0.0 {
+            (old.y / 16.0).ceil() * 16.0
+        } else {
+            (old.y / 16.0).floor() * 16.0
+        };
+
+        let mut row = (y / 16.0) as isize;
+
+        while (row as f32 * 16.0 - new.y) * height.signum() < 0.0 {
+
+            let current_height = row as f32 * 16.0 - old.y;
+            let x = old.x + (new.x - old.x) * current_height / height;
+
+            // Find tile on x, y
+            if x > 0.0 && y > 0.0 {
+
                 let col = (x / 16.0) as usize;
 
-                if let Some((tile, _)) = self.tiles.get((row, col)) {
+                let row = if height > 0.0 {
+                    row
+                } else {
+                    row - 1
+                };
+
+                if let Some((tile, _)) = self.tiles.get((row as usize, col)) {
                     if tile.from_top {
                         return Some((CollisionAxis::Y, Vector2::new(x, y)));
                     }
@@ -424,10 +512,11 @@ impl Map {
 
             }
 
-            y += 16.0;
+            row += height.signum() as isize;
         }
 
         None
     }
+
 }