feat(entities): fase 4 - moviment de la momia amb col·lisió, z-order per peus i contacte amb el jugador

source/game/entities/concrete/rolling_rock.cpp

@@ -4,6 +4,7 @@
 
 #include "game/entities/entity_factory.hpp"
 #include "game/entities/event_bus.hpp"
+#include "game/map/map.hpp"
 
 namespace {
 
@@ -42,6 +43,23 @@ RollingRock::RollingRock(const fkyaml::node& yaml) {
     applyInitialDirection(initial, *this);
 }
 
+void RollingRock::step(float delta_time) {
+    const float DX = dir_x_ * speed_ * delta_time;
+    const float DY = dir_y_ * speed_ * delta_time;
+    if (DX == 0.0F && DY == 0.0F) { return; }
+
+    auto candidate = getCollisionRect();
+    candidate.x += DX;
+    candidate.y += DY;
+    if (Map::insidePlayfield(candidate) && !Map::collides(candidate)) {
+        pixel_rect_.x += DX;
+        pixel_rect_.y += DY;
+        return;
+    }
+    // Bloqueig: aturada definitiva (la roca no rebota).
+    setDirection(0.0F, 0.0F);
+}
+
 void RollingRock::onPlayerContact(Player* /*player*/) {
     if (bus_ != nullptr) { bus_->publish("player_hit", getDamage()); }
 }