// Physics example. // This sample demonstrates: // - Creating both static and moving physics objects to a scene // - Displaying physics debug geometry // - Using the Skybox component for setting up an unmoving sky // - Saving a scene to a file and loading it to restore a previous state #include "Scripts/Utilities/Sample.as" void Start() { // Execute the common startup for samples SampleStart(); // Create the scene content CreateScene(); // Create the UI content CreateInstructions(); // Setup the viewport for displaying the scene SetupViewport(); // Hook up to the frame update and render post-update events SubscribeToEvents(); } void CreateScene() { scene_ = Scene(); // Create octree, use default volume (-1000, -1000, -1000) to (1000, 1000, 1000) // Create a physics simulation world with default parameters, which will update at 60fps. Like the Octree must // exist before creating drawable components, the PhysicsWorld must exist before creating physics components. // Finally, create a DebugRenderer component so that we can draw physics debug geometry scene_.CreateComponent("Octree"); scene_.CreateComponent("PhysicsWorld"); scene_.CreateComponent("DebugRenderer"); // Create a Zone component for ambient lighting & fog control Node@ zoneNode = scene_.CreateChild("Zone"); Zone@ zone = zoneNode.CreateComponent("Zone"); zone.boundingBox = BoundingBox(-1000.0f, 1000.0f); zone.ambientColor = Color(0.15f, 0.15f, 0.15f); zone.fogColor = Color(1.0f, 1.0f, 1.0f); zone.fogStart = 300.0f; zone.fogEnd = 500.0f; // Create a directional light to the world. Enable cascaded shadows on it Node@ lightNode = scene_.CreateChild("DirectionalLight"); lightNode.direction = Vector3(0.6f, -1.0f, 0.8f); Light@ light = lightNode.CreateComponent("Light"); light.lightType = LIGHT_DIRECTIONAL; light.castShadows = true; light.shadowBias = BiasParameters(0.00025f, 0.5f); // Set cascade splits at 10, 50 and 200 world units, fade shadows out at 80% of maximum shadow distance light.shadowCascade = CascadeParameters(10.0f, 50.0f, 200.0f, 0.0f, 0.8f); // Create skybox. The Skybox component is used like StaticModel, but it will be always located at the camera, giving the // illusion of the box planes being far away. Use just the ordinary Box model and a suitable material, whose shader will // generate the necessary 3D texture coordinates for cube mapping Node@ skyNode = scene_.CreateChild("Sky"); skyNode.SetScale(500.0f); // The scale actually does not matter Skybox@ skybox = skyNode.CreateComponent("Skybox"); skybox.model = cache.GetResource("Model", "Models/Box.mdl"); skybox.material = cache.GetResource("Material", "Materials/Skybox.xml"); { // Create a floor object, 1000 x 1000 world units. Adjust position so that the ground is at zero Y Node@ floorNode = scene_.CreateChild("Floor"); floorNode.position = Vector3(0.0f, -0.5f, 0.0f); floorNode.scale = Vector3(1000.0f, 1.0f, 1000.0f); StaticModel@ floorObject = floorNode.CreateComponent("StaticModel"); floorObject.model = cache.GetResource("Model", "Models/Box.mdl"); floorObject.material = cache.GetResource("Material", "Materials/StoneTiled.xml"); // Make the floor physical by adding RigidBody and CollisionShape components. The RigidBody's default // parameters make the object static (zero mass.) Note that a CollisionShape by itself will not participate // in the physics simulation RigidBody@ body = floorNode.CreateComponent("RigidBody"); CollisionShape@ shape = floorNode.CreateComponent("CollisionShape"); // Set a box shape of size 1 x 1 x 1 for collision. The shape will be scaled with the scene node scale, so the // rendering and physics representation sizes should match (the box model is also 1 x 1 x 1.) shape.SetBox(Vector3(1.0f, 1.0f, 1.0f)); } { // Create a pyramid of movable physics objects for (int y = 0; y < 8; ++y) { for (int x = -y; x <= y; ++x) { Node@ boxNode = scene_.CreateChild("Box"); boxNode.position = Vector3(x, -y + 8.0f, 0.0f); StaticModel@ boxObject = boxNode.CreateComponent("StaticModel"); boxObject.model = cache.GetResource("Model", "Models/Box.mdl"); boxObject.material = cache.GetResource("Material", "Materials/StoneEnvMapSmall.xml"); boxObject.castShadows = true; // Create RigidBody and CollisionShape components like above. Give the RigidBody mass to make it movable // and also adjust friction. The actual mass is not important; only the mass ratios between colliding // objects are significant RigidBody@ body = boxNode.CreateComponent("RigidBody"); body.mass = 1.0f; body.friction = 0.75f; CollisionShape@ shape = boxNode.CreateComponent("CollisionShape"); shape.SetBox(Vector3(1.0f, 1.0f, 1.0f)); } } } // Create the camera. Set far clip to match the fog. Note: now we actually create the camera node outside // the scene, because we want it to be unaffected by scene load / save cameraNode = Node(); Camera@ camera = cameraNode.CreateComponent("Camera"); camera.farClip = 500.0f; // Set an initial position for the camera scene node above the floor cameraNode.position = Vector3(0.0f, 5.0f, -20.0f); } void CreateInstructions() { // Construct new Text object, set string to display and font to use Text@ instructionText = ui.root.CreateChild("Text"); instructionText.text = "Use WASD keys and mouse to move\n" "LMB to spawn physics objects\n" "F5 to save scene, F7 to load\n" "Space to toggle physics debug geometry"; instructionText.SetFont(cache.GetResource("Font", "Fonts/Anonymous Pro.ttf"), 15); // The text has multiple rows. Center them in relation to each other instructionText.textAlignment = HA_CENTER; // Position the text relative to the screen center instructionText.horizontalAlignment = HA_CENTER; instructionText.verticalAlignment = VA_CENTER; instructionText.SetPosition(0, ui.root.height / 4); } void SetupViewport() { // Set up a viewport to the Renderer subsystem so that the 3D scene can be seen Viewport@ viewport = Viewport(scene_, cameraNode.GetComponent("Camera")); renderer.viewports[0] = viewport; } void SubscribeToEvents() { // Subscribe HandleUpdate() function for processing update events SubscribeToEvent("Update", "HandleUpdate"); // Subscribe HandlePostRenderUpdate() function for processing the post-render update event, during which we request // debug geometry SubscribeToEvent("PostRenderUpdate", "HandlePostRenderUpdate"); } void MoveCamera(float timeStep) { // Do not move if the UI has a focused element (the console) if (ui.focusElement !is null) return; // Movement speed as world units per second const float MOVE_SPEED = 20.0f; // Mouse sensitivity as degrees per pixel const float MOUSE_SENSITIVITY = 0.1f; // Use this frame's mouse motion to adjust camera node yaw and pitch. Clamp the pitch between -90 and 90 degrees IntVector2 mouseMove = input.mouseMove; yaw += MOUSE_SENSITIVITY * mouseMove.x; pitch += MOUSE_SENSITIVITY * mouseMove.y; pitch = Clamp(pitch, -90.0f, 90.0f); // Construct new orientation for the camera scene node from yaw and pitch. Roll is fixed to zero cameraNode.rotation = Quaternion(pitch, yaw, 0.0f); // Read WASD keys and move the camera scene node to the corresponding direction if they are pressed if (input.keyDown['W']) cameraNode.Translate(Vector3(0.0f, 0.0f, 1.0f) * MOVE_SPEED * timeStep); if (input.keyDown['S']) cameraNode.Translate(Vector3(0.0f, 0.0f, -1.0f) * MOVE_SPEED * timeStep); if (input.keyDown['A']) cameraNode.Translate(Vector3(-1.0f, 0.0f, 0.0f) * MOVE_SPEED * timeStep); if (input.keyDown['D']) cameraNode.Translate(Vector3(1.0f, 0.0f, 0.0f) * MOVE_SPEED * timeStep); // "Shoot" a physics object with left mousebutton if (input.mouseButtonPress[MOUSEB_LEFT]) SpawnObject(); // Check for loading / saving the scene. Save the scene to the file Data/Scenes/Physics.xml relative to the executable // directory if (input.keyPress[KEY_F5]) { File saveFile(fileSystem.programDir + "Data/Scenes/Physics.xml", FILE_WRITE); scene_.SaveXML(saveFile); } if (input.keyPress[KEY_F7]) { File loadFile(fileSystem.programDir + "Data/Scenes/Physics.xml", FILE_READ); scene_.LoadXML(loadFile); } // Toggle debug geometry with space if (input.keyPress[KEY_SPACE]) drawDebug = !drawDebug; } void SpawnObject() { // Create a smaller box at camera position Node@ boxNode = scene_.CreateChild("SmallBox"); boxNode.position = cameraNode.position; boxNode.rotation = cameraNode.rotation; boxNode.SetScale(0.25f); StaticModel@ boxObject = boxNode.CreateComponent("StaticModel"); boxObject.model = cache.GetResource("Model", "Models/Box.mdl"); boxObject.material = cache.GetResource("Material", "Materials/StoneEnvMapSmall.xml"); boxObject.castShadows = true; // Create physics components, use a smaller mass also RigidBody@ body = boxNode.CreateComponent("RigidBody"); body.mass = 0.25f; body.friction = 0.75f; CollisionShape@ shape = boxNode.CreateComponent("CollisionShape"); shape.SetBox(Vector3(1.0f, 1.0f, 1.0f)); const float OBJECT_VELOCITY = 10.0f; // Set initial velocity for the RigidBody based on camera forward vector. Add also a slight up component // to overcome gravity better body.linearVelocity = cameraNode.rotation * Vector3(0.0f, 0.25f, 1.0f) * OBJECT_VELOCITY; } void HandleUpdate(StringHash eventType, VariantMap& eventData) { // Take the frame time step, which is stored as a float float timeStep = eventData["TimeStep"].GetFloat(); // Move the camera, scale movement with time step MoveCamera(timeStep); } void HandlePostRenderUpdate(StringHash eventType, VariantMap& eventData) { // If draw debug mode is enabled, draw physics debug geometry. Use depth test to make the result easier to interpret // Note the convenience accessor to the physics world component if (drawDebug) scene_.physicsWorld.DrawDebugGeometry(true); } // Create XML patch instructions for screen joystick layout specific to this sample app String patchInstructions = "" + " " + " Spawn" + " " + " " + " " + " " + " " + " " + " " + " Debug" + " " + " " + " " + " " + " " + " " + "";