1 files changed, 73 insertions, 0 deletions
diff --git a/game_server/src/collide.rs b/game_server/src/collide.rs
new file mode 100644
index 0000000..4217e7f
--- /dev/null
+++ b/game_server/src/collide.rs
@@ -0,0 +1,73 @@
+use crate::maths::{Vec2, Box, RBox};
+
+pub trait Collide<Rhs> {
+    fn collides(&self, other: &Rhs) -> bool;
+}
+
+impl Collide<Vec2> for Vec2 {
+    fn collides(&self, other: &Self) -> bool {
+        self == other
+    }
+}
+
+impl Collide<Vec2> for Box {
+    fn collides(&self, other: &Vec2) -> bool {
+        self.pos < other && other < self.pos + self.size 
+    }
+}
+
+impl Collide<Box> for Box {
+    fn collides(&self, other: &Self) -> bool {
+        self.collides(other.pos)
+        || self.collides(other.pos + Vec2{x: other.x, y: 0})
+        || self.collides(other.pos + Vec2{x: 0, y: other.y})
+        || self.collides(other.pos + other.size)
+
+        || other.collides(self.pos)
+        || other.collides(self.pos + Vec2{x: self.x, y: 0})
+        || other.collides(self.pos + Vec2{x: 0, y: self.y})
+        || other.collides(self.pos + self.size)
+    }
+}
+
+impl Collide<Vec2> for RBox {
+    fn collides(&self, other: &Vec2) -> bool {
+        let dx = self.size.x;
+        let dy = self.size.y;
+        let len = f32::sqrt(dx*dx+dy*dy);
+        dx /= len;
+        dy /= len;
+
+        let dax = other.x - self.p1.x;
+        let day = other.y - self.p1.y;
+        
+        let dot = dax * dx + day * dy;
+        let px = self.pos.x + dx * dot;
+        let py = self.pos.y + dy * dot;
+       
+        if !(self.pos < px && px < self.pos + self.size) {
+            return false; 
+        } 
+
+        let ddx = other.x-px; 
+        let ddy = other.y-py;
+        let manhattenDistance = ddx + ddy;
+
+        manhattenDistance < self.w 
+    }
+}
+
+impl Collide<Box> for RBox {
+    fn collides(&self, other: &Box) -> bool {
+        self.collides(other.pos)
+        || self.collides(other.pos + Vec2{x: other.x, y: 0})
+        || self.collides(other.pos + Vec2{x: 0, y: other.y})
+        || self.collides(other.pos + other.size)
+        
+        || other.collides(self.pos)
+        || other.collides(self.pos + Vec2{x: self.x, y: 0})
+        || other.collides(self.pos + Vec2{x: 0, y: self.y})
+        || other.collides(self.pos + self.size)
+        
+    }
+}