basic version without world movement

Co-authored-by: Copilot <copilot@github.com>

src/game/gameUtils.js

@@ -0,0 +1,47 @@
+// Game utilities for player controls and movement
+
+
+export function updatePlayerPosition(player, platforms) {
+  let elevationGain = 0;
+
+  // Controls
+  player.vel.x = 0;
+  if (keyIsDown(LEFT_ARROW)) {
+    player.vel.x = -5;
+  }
+  if (keyIsDown(RIGHT_ARROW)) {
+    player.vel.x = 5;
+  }
+
+  // Jumping thrue platforms
+  for (let plat of platforms) {
+    if (player.vel.y <= 0 && player.y > plat.y) {
+      plat.collider = 'none';
+    } else {
+      plat.collider = 'static';
+    }
+  }
+
+
+  // Automatic jumping
+  if (player.vel.y >= 0) {
+    player.collides(platforms, (player, platform) => {
+      player.vel.y = -7.5;
+
+      if (player.elevation < platform.elevation) {
+        elevationGain = platform.elevation - player.elevation;
+        player.elevation = platform.elevation;
+      }
+    });
+  }
+
+  // Wrap horizontally around canvas edges
+  if (player.x > width) {
+    player.x = 0;
+  } else if (player.x < 0) {
+    player.x = width;
+  }
+
+  return elevationGain;
+}
+