-- Urho2D physics rope sample. -- This sample demonstrates: -- - Create revolute constraint -- - Create roop constraint -- - Displaying physics debug geometry require "LuaScripts/Utilities/Sample" function 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 events SubscribeToEvents() end function CreateScene() scene_ = Scene() -- Create the Octree component to the scene. This is required before adding any drawable components, or else nothing will -- show up. The default octree volume will be from (-1000, -1000, -1000) to (1000, 1000, 1000) in world coordinates it -- is also legal to place objects outside the volume but their visibility can then not be checked in a hierarchically -- optimizing manner scene_:CreateComponent("Octree") scene_:CreateComponent("DebugRenderer") -- Create a scene node for the camera, which we will move around -- The camera will use default settings (1000 far clip distance, 45 degrees FOV, set aspect ratio automatically) cameraNode = scene_:CreateChild("Camera") -- Set an initial position for the camera scene node above the plane cameraNode.position = Vector3(0.0, 5.0, -10.0) local camera = cameraNode:CreateComponent("Camera") camera.orthographic = true camera.orthoSize = graphics.height * 0.05 -- Create 2D physics world component local physicsWorld = scene_:CreateComponent("PhysicsWorld2D") physicsWorld.drawJoint = true -- Create ground. local groundNode = scene_:CreateChild("Ground") -- Create 2D rigid body for gound local groundBody = groundNode:CreateComponent("RigidBody2D") -- Create edge collider for ground local groundShape = groundNode:CreateComponent("CollisionEdge2D") groundShape:SetVertices(Vector2(-40.0, 0.0), Vector2(40.0, 0.0)) local y = 15.0 local prevBody = groundBody local NUM_OBJECTS = 10 for i = 0, NUM_OBJECTS - 1 do local node = scene_:CreateChild("RigidBody") -- Create rigid body local body = node:CreateComponent("RigidBody2D") body.bodyType = BT_DYNAMIC -- Create box local box = node:CreateComponent("CollisionBox2D") -- Set friction box.friction = 0.2 -- Set mask bits. box.maskBits = 0xFFFF - 0x0002 if i == NUM_OBJECTS - 1 then node.position = Vector3(1.0 * i, y, 0.0) body.angularDamping = 0.4 box:SetSize(3.0, 3.0) box.density = 100.0 box.categoryBits = 0x0002 else node.position = Vector3(0.5 + 1.0 * i, y, 0.0) box:SetSize(1.0, 0.25) box.density = 20.0 box.categoryBits = 0x0001 end local joint = node:CreateComponent("ConstraintRevolute2D") joint.otherBody = prevBody joint.anchor = Vector2(i, y) joint.collideConnected = false prevBody = body end local constraintRope = groundNode:CreateComponent("ConstraintRope2D") constraintRope.otherBody = prevBody constraintRope.ownerBodyAnchor = Vector2(0.0, y) constraintRope.maxLength = NUM_OBJECTS - 1.0 + 0.01 end function CreateInstructions() -- Construct new Text object, set string to display and font to use local instructionText = ui.root:CreateChild("Text") instructionText:SetText("Use WASD keys and mouse to move, Use PageUp PageDown to zoom.") instructionText:SetFont(cache:GetResource("Font", "Fonts/Anonymous Pro.ttf"), 15) -- Position the text relative to the screen center instructionText.horizontalAlignment = HA_CENTER instructionText.verticalAlignment = VA_CENTER instructionText:SetPosition(0, ui.root.height / 4) end function SetupViewport() -- Set up a viewport to the Renderer subsystem so that the 3D scene can be seen. We need to define the scene and the camera -- at minimum. Additionally we could configure the viewport screen size and the rendering path (eg. forward / deferred) to -- use, but now we just use full screen and default render path configured in the engine command line options local viewport = Viewport:new(scene_, cameraNode:GetComponent("Camera")) renderer:SetViewport(0, viewport) end function MoveCamera(timeStep) -- Do not move if the UI has a focused element (the console) if ui.focusElement ~= nil then return end -- Movement speed as world units per second local MOVE_SPEED = 4.0 -- Read WASD keys and move the camera scene node to the corresponding direction if they are pressed if input:GetKeyDown(KEY_W) then cameraNode:Translate(Vector3(0.0, 1.0, 0.0) * MOVE_SPEED * timeStep) end if input:GetKeyDown(KEY_S) then cameraNode:Translate(Vector3(0.0, -1.0, 0.0) * MOVE_SPEED * timeStep) end if input:GetKeyDown(KEY_A) then cameraNode:Translate(Vector3(-1.0, 0.0, 0.0) * MOVE_SPEED * timeStep) end if input:GetKeyDown(KEY_D) then cameraNode:Translate(Vector3(1.0, 0.0, 0.0) * MOVE_SPEED * timeStep) end if input:GetKeyDown(KEY_PAGEUP) then local camera = cameraNode:GetComponent("Camera") camera.zoom = camera.zoom * 1.01 end if input:GetKeyDown(KEY_PAGEDOWN) then local camera = cameraNode:GetComponent("Camera") camera.zoom = camera.zoom * 0.99 end end function SubscribeToEvents() -- Subscribe HandleUpdate() function for processing update events SubscribeToEvent("Update", "HandleUpdate") -- Unsubscribe the SceneUpdate event from base class to prevent camera pitch and yaw in 2D sample UnsubscribeFromEvent("SceneUpdate") end function HandleUpdate(eventType, eventData) -- Take the frame time step, which is stored as a float local timeStep = eventData:GetFloat("TimeStep") -- Move the camera, scale movement with time step MoveCamera(timeStep) local physicsWorld = scene_:GetComponent("PhysicsWorld2D") physicsWorld:DrawDebugGeometry() end -- Create XML patch instructions for screen joystick layout specific to this sample app function GetScreenJoystickPatchString() return "" .. " " .. " Zoom In" .. " " .. " " .. " " .. " " .. " " .. " " .. " " .. " Zoom Out" .. " " .. " " .. " " .. " " .. " " .. " " .. "" end