• Home

StackTheBox Demo

 import Felgo 4.0 // for the gaming components
 import QtQuick 2.0 // for the Image element
 import "entities"

 GameWindow {
   id: gameWindow

   // You get free licenseKeys from https://felgo.com/licenseKey
   // With a licenseKey you can:
   //  * Publish your games & apps for the app stores
   //  * Remove the Felgo Splash Screen or set a custom one (available with the Pro Licenses)
   //  * Add plugins to monetize, analyze & improve your apps (available with the Pro Licenses)
   //licenseKey: "<generate one from https://felgo.com/licenseKey>"

   activeScene: scene

   EntityManager {
     id: entityManager
     entityContainer: scene
   }

   Rectangle {
     anchors.fill: parent
     color: "black"
   }

   Scene {
     id: scene
     width: 480
     height: 320

     // gets increased when a new box is created, and reset to 0 when a new game is started
     // start with 1, because initially 1 Box is created
     property int createdBoxes: 1

     // this is the required minimum distance from the left and from the right (the scene.width)
     // when the box is rotated at 90°, its distance from the center is box1.width*Sqrt2, because width and height are the same
     // the hint about this issue was kindly provided by Martin Eigel
     property real safetyDistance: -1

     // display the amount of stacked boxes
     Text {
       text: "Boxes: " + scene.createdBoxes
       color: "white"
       z: 1 // put on top of everything else in the Scene
     }

     PhysicsWorld {
       id: physicsWorld
       gravity.y: 9.81 // make the objects fall faster
       debugDrawVisible: false

       // these are performance settings to avoid boxes colliding too far together
       // set them as low as possible so it still looks good
       updatesPerSecondForPhysics: 60
       velocityIterations: 5
       positionIterations: 5
     }

     Component {
       id: mouseJoint
       Item {
         id: jointItem

         // make important joint properties accessible
         property alias bodyB: joint.bodyB
         property alias target: joint.target

         // set up the mouse joint
         MouseJoint {
           id: joint
           // make this high enough so the box with its density is moved quickly
           maxForce: 30000 * physicsWorld.pixelsPerMeter
           // The damping ratio. 0 = no damping, 1 = critical damping. Default is 0.7
           dampingRatio: 1
           // The response speed, default is 5
           frequencyHz: 2
         }

         // also destroy joint if a box is destroyed
         Connections {
           // joint.bodyB.target is the box entity connected with the joint
           target: joint.bodyB !== null ? joint.bodyB.target : null
           onEntityDestroyed: { joint.bodyB = null; jointItem.destroy() }
         }
       }
     }

     // when the user presses a box, move it towards the touch position
     MouseArea {
       anchors.fill: parent

       property Body selectedBody: null
       property Item mouseJointWhileDragging: null

       onPressed: {

         selectedBody = physicsWorld.bodyAt(Qt.point(mouseX, mouseY));
         console.debug("selected body at position", mouseX, mouseY, ":", selectedBody);
         // if the user selected a body, this if-check is true
         if(selectedBody) {
           // create a new mouseJoint
           var properties = {
             // set the target position to the current touch position (initial position)
             target: Qt.point(mouseX, mouseY),

             // body B is the one that actually moves -> connect the joint with the body
             bodyB: selectedBody
           }

           mouseJointWhileDragging = mouseJoint.createObject(physicsWorld, properties)
         }
       }

       onPositionChanged: {
         // this check is necessary, because the user might also drag when no initial body was selected
         if (mouseJointWhileDragging)
           mouseJointWhileDragging.target = Qt.point(mouseX, mouseY)
       }
       onReleased: {
         // if the user pressed a body initially, remove the created MouseJoint
         if(selectedBody) {
           selectedBody = null
           if (mouseJointWhileDragging)
             mouseJointWhileDragging.destroy()
         }
       }
     }

     Box {
       id: box1
       entityId: "box1"
       x: scene.width/2
       y: 50 // position a bit to the bottom so it doesn't collide with the top wall

       Component.onCompleted: {

         // initialize the safetyZoneHoriztonal after the box is known
         if(scene.safetyDistance === -1) {
           // add a little addtional offset, to avoid generation at the very border
           scene.safetyDistance = box1.width*Math.SQRT2/2 + leftWall.width + 5
           console.debug("init safetyZoneHorizontal with", scene.safetyDistance)
         }

       }

     }

     Wall {
       // bottom wall
       height: 20
       anchors {
         bottom: scene.bottom
         left: scene.left
         right: scene.right
       }
     }

     Wall {
       // left wall
       id: leftWall
       width: 20
       height: scene.height
       anchors {
         left: scene.left
       }
     }

     Wall {
       // right wall
       width: 20
       height: scene.height
       anchors {
         right: scene.right
       }
     }
     Wall {
       // top wall
       id: topWall
       height: 20
       width: scene.width
       anchors {
         top: scene.top
       }
       color: "red" // make the top wall red
       onCollidedWithBox: {
         // gets called when the wall collides with a box, and the game should restart

         // remove all entities of type "box", but not the walls
         entityManager.removeEntitiesByFilter(["box"]);
         // reset the createdBoxes amount
         scene.createdBoxes = 0;
       }
     }

     // for toggling audio and particles
     Column {
       anchors.right: parent.right

       spacing: 5
       SimpleButton {
         text: "Toggle Audio"
         onClicked: settings.soundEnabled = !settings.soundEnabled
         anchors.right: parent.right
       }
       SimpleButton {
         visible: false
         text: "Toggle Particles"
         onClicked: settings.particlesEnabled = !settings.particlesEnabled
       }
     }

     Timer {
       id: timer
       interval: generateRandomInterval()
       running: true // start running from the beginning, when the scene is loaded
       repeat: true // otherwise restart wont work

       onTriggered: {

         var newEntityProperties = {
           // vary x between [ safetyZoneHoriztonal ... width-safetyZoneHoriztonal]
           x: utils.generateRandomValueBetween(scene.safetyDistance, scene.width-scene.safetyDistance),
           y: scene.safetyDistance, // position on top of the scene, at least below the top wall
           rotation: Math.random()*360
         }

         entityManager.createEntityFromUrlWithProperties(
               Qt.resolvedUrl("entities/Box.qml"),
               newEntityProperties);

         // increase the createdBoxes number
         scene.createdBoxes++

         timer.interval = generateRandomInterval()

         // restart the timer
         timer.restart()
       }

       function generateRandomInterval() {
         // recalculate new interval between 1000 and 3000
         return utils.generateRandomValueBetween(1000, 3000);
       }
     }