examples -> example

example/asteroids.cpp

@@ -0,0 +1,71 @@
+// asteroids.cpp
+// Copyright (c) 2018-2025 Jean-Louis Leroy
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+// Example for Wikipedia
+
+#include <boost/openmethod.hpp>
+#include <boost/openmethod/compiler.hpp>
+
+using boost::openmethod::virtual_ptr;
+
+class Thing {
+  public:
+    virtual ~Thing() {
+    }
+};
+
+class Asteroid : public Thing {};
+
+class Spaceship : public Thing {};
+
+BOOST_OPENMETHOD_CLASSES(Thing, Spaceship, Asteroid);
+
+BOOST_OPENMETHOD(collideWith, (virtual_ptr<Thing>, virtual_ptr<Thing>), void);
+
+BOOST_OPENMETHOD_OVERRIDE(
+    collideWith, (virtual_ptr<Thing> /*left*/, virtual_ptr<Thing> /*right*/),
+    void) {
+    // default collision handling
+}
+
+BOOST_OPENMETHOD_OVERRIDE(
+    collideWith,
+    (virtual_ptr<Asteroid> /*left*/, virtual_ptr<Asteroid> /*right*/), void) {
+    // handle Asteroid-Asteroid collision
+}
+
+BOOST_OPENMETHOD_OVERRIDE(
+    collideWith,
+    (virtual_ptr<Asteroid> /*left*/, virtual_ptr<Spaceship> /*right*/), void) {
+    // handle Asteroid-Spaceship collision
+}
+
+BOOST_OPENMETHOD_OVERRIDE(
+    collideWith,
+    (virtual_ptr<Spaceship> /*left*/, virtual_ptr<Asteroid> /*right*/), void) {
+    // handle Spaceship-Asteroid collision
+}
+
+BOOST_OPENMETHOD_OVERRIDE(
+    collideWith,
+    (virtual_ptr<Spaceship> /*left*/, virtual_ptr<Spaceship> /*right*/), void) {
+    // handle Spaceship-Spaceship collision
+}
+
+auto main() -> int {
+    boost::openmethod::initialize();
+
+    Asteroid a1, a2;
+    Spaceship s1, s2;
+
+    collideWith(a1, a2);
+    collideWith(a1, s1);
+
+    collideWith(s1, s2);
+    collideWith(s1, a1);
+
+    return 0;
+}