better collision-detection with maybe only one bug

GitOrigin-RevId: c205dfcd6c

Jumpy.Shared/Player.cs

@@ -35,22 +35,33 @@ namespace Jumpy {
       AirState oldAirState = airState;
       UpdateFromGamePad(time, gamePad);
 
-      Rectangle playerBbox = new Rectangle(position.X - spriteWidth, position.Y - 8, spriteWidth * 2, 27);
+      Rectangle oldBbox = new Rectangle(oldPosition.X - spriteWidth, oldPosition.Y - 7, spriteWidth * 2, 26);
+      Rectangle playerBbox = new Rectangle(position.X - spriteWidth, position.Y - 7, spriteWidth * 2, 26);
       bool standingOnGround = false;
       foreach (var rect in collisionTargets) {
-        playerBbox = new Rectangle(position.X - spriteWidth, position.Y - 8, spriteWidth * 2, 27);
+        playerBbox = new Rectangle(position.X - spriteWidth, position.Y - 7, spriteWidth * 2, 26);
 
+        // first we check for left-right collisions...
+        if (playerBbox.Intersects(rect)) {
+          if (oldBbox.Right <= rect.Left && playerBbox.Right > rect.Left) {
+            position.X = rect.Left - spriteWidth;
+          }
+          if (oldBbox.Left >= rect.Right && playerBbox.Left < rect.Right) {
+            position.X = rect.Right + spriteWidth;
+          }
+          playerBbox = new Rectangle(position.X - spriteWidth, position.Y - 7, spriteWidth * 2, 26);
+        }
+        // after fixing that, we check for hitting our head or hitting the ground.
         if (playerBbox.Intersects(rect)) {
           if (oldPosition.Y > position.Y) {
             int diff = playerBbox.Top - rect.Bottom;
             position.Y -= diff;
-            ySpeed *= 0.9;
+            // ySpeed *= 0.9;
           } else {
             airState = AirState.Ground;
             int diff = playerBbox.Bottom - rect.Top;
             position.Y -= diff;
           }
-          Debug.AddRect(rect, Color.Yellow);
         } else {
           playerBbox.Height += 1;
           if (playerBbox.Intersects(rect)) {