feat: add experimental game engine & demo game, fix ACPI events

programs/include/engine/collision.h

@@ -0,0 +1,48 @@
+/*
+ * collision.h
+ * MontaukOS 2D Game Engine - Collision Detection
+ * AABB overlap testing and tile-based collision response
+ * Copyright (c) 2026 Daniel Hammer
+ */
+
+#pragma once
+#include <cstdint>
+#include "engine/tilemap.h"
+
+namespace engine {
+
+struct AABB {
+    float x, y, w, h;
+
+    bool overlaps(const AABB& other) const {
+        return x < other.x + other.w && x + w > other.x &&
+               y < other.y + other.h && y + h > other.y;
+    }
+
+    bool contains_point(float px, float py) const {
+        return px >= x && px < x + w && py >= y && py < y + h;
+    }
+};
+
+// Try to move an entity by (dx, dy) on the tilemap.
+// Uses separate X/Y axis resolution so the entity slides along walls.
+// box: the entity's collision box in world pixel coordinates.
+// Returns adjusted dx, dy after collision.
+inline void resolve_tilemap_collision(const Tilemap& map,
+                                      float bx, float by, float bw, float bh,
+                                      float& dx, float& dy) {
+    // Try X movement
+    float new_x = bx + dx;
+    if (map.collides((int)new_x, (int)by, (int)bw, (int)bh)) {
+        dx = 0.0f;
+        new_x = bx;
+    }
+
+    // Try Y movement
+    float new_y = by + dy;
+    if (map.collides((int)new_x, (int)new_y, (int)bw, (int)bh)) {
+        dy = 0.0f;
+    }
+}
+
+} // namespace engine