just check intersecting tiles

src/main.rs

@@ -70,7 +70,7 @@ fn main() {
     };
 
     let mut camera = Camera::new(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
-    let mut layer = Layer::new(30, 20, Tile::Empty);
+    let mut layer = Layer::new(30, 20, TILE_WIDTH, TILE_HEIGHT, Tile::Empty);
 
     for x in range(0, 14) {
         layer.set_tile(x, 14, Tile::Floor);
@@ -104,7 +104,7 @@ fn main() {
                     player.velocity.x = -4.0;
                 } else if key == KeyCode::Up {
                     if player.on_ground {
-                        player.velocity.y = -8.0;
+                        player.velocity.y = -12.0;
                         player.on_ground = false;
                     }
                 }
@@ -115,8 +115,8 @@ fn main() {
                 } else if key == KeyCode::Left {
                     player.velocity.x = 0.0;
                 } else if key == KeyCode::Up {
-                    if player.velocity.y < -4.0 {
-                        player.velocity.y = -4.0;
+                    if player.velocity.y < -6.0 {
+                        player.velocity.y = -6.0;
                     }
                 }
             },
@@ -128,15 +128,29 @@ fn main() {
 
             player.on_ground = false;
 
-            for y in range(0, 20) {
-                for x in range(0, 30) {
+            let tiles_intersect = layer.get_intersecting(&player.get_rect());
+
+            let mut skip = false;
+
+            if tiles_intersect.x < 0 || tiles_intersect.x + tiles_intersect.w > 30 - 1 {
+                skip = true;
+            }
+            else if tiles_intersect.y < 0 || tiles_intersect.y + tiles_intersect.h > 20 - 1 {
+                skip = true;
+            }
+
+            if skip == false {
+                for y in range(tiles_intersect.y, tiles_intersect.y + tiles_intersect.h + 1) {
+                    for x in range(tiles_intersect.x, tiles_intersect.x + tiles_intersect.w + 1) {
+                        let player_rect = player.get_rect();
+
                         match *layer.get_tile(x, y) {
                             Tile::Empty => (),
                             Tile::Floor => {
-                            let object = Rect::new(x * TILE_WIDTH, y * TILE_HEIGHT, TILE_WIDTH, TILE_HEIGHT);
+                                let object_rect = Rect::new(x * TILE_WIDTH, y * TILE_HEIGHT, TILE_WIDTH, TILE_HEIGHT);
 
-                            if collision_detection(&object, &player.get_rect()) {
-                                let intersect = collision_intersect(&object, &player.get_rect());
+                                if collision_detection(&object_rect, &player_rect) {
+                                    let intersect = collision_intersect(&object_rect, &player_rect);
 
                                     if intersect.w >= intersect.h {
                                         let mut delta = intersect.h as f32;
@@ -164,6 +178,7 @@ fn main() {
                         }
                     }
                 }
+            }
 
             lag -= MS_PER_UPDATE;
         }

src/player.rs

@@ -1,14 +1,9 @@
-extern crate sdl2;
-
-
 use sdl2::render::Renderer;
 use sdl2::pixels::Color;
 use sdl2::rect::Rect;
 
 use vec::Vec2;
 
-use vec;
-
 
 pub struct Player {
     pub position: Vec2<f32>,

src/tile.rs

@@ -1,13 +1,20 @@
+use sdl2::rect::Rect;
+
+
 pub struct Layer<T> {
     tiles: Vec<T>,
-    width: i32
+    width: i32,
+    tile_width: i32,
+    tile_height: i32
 }
 
 impl<T> Layer<T> where T: Clone {
-    pub fn new(width: i32, height: i32, tile: T) -> Layer<T> {
+    pub fn new(width: i32, height: i32, tile_width: i32, tile_height: i32, tile: T) -> Layer<T> {
         Layer {
             tiles: Vec::from_elem((width * height) as uint, tile),
-            width: width
+            width: width,
+            tile_width: tile_width,
+            tile_height: tile_height
         }
     }
 
@@ -22,4 +29,14 @@ impl<T> Layer<T> where T: Clone {
 
         *self.tiles.index_mut(&offset) = tile;
     }
+
+    pub fn get_intersecting(&self, rect: &Rect) -> Rect {
+        let x = rect.x / self.tile_width;
+        let w = rect.w / self.tile_width;
+
+        let y = rect.y / self.tile_height;
+        let h = rect.h / self.tile_height;
+
+        Rect::new(x, y, w, h)
+    }
 }