Qt 5.7 | Qt Multimedia | AudioEngine Example | audioengine.qml Example File

Qt 5.7.1 Reference Documentation

# audioengine.qml Example File

multimedia/audioengine/qml/audioengine.qml

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       ** This file is part of the examples of the Qt Toolkit.
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      import QtAudioEngine 1.0
      import QtQuick 2.0
      import "content"

      Rectangle {
          color:"white"
          id: root
          width: 300
          height: 500
          property int radius : 100
          property real twoPi : Math.PI + Math.PI

          MyAudioEngine {
              id:audioEngine
              listener.position : Qt.vector3d(observer.x, observer.y, 0);
          }

          Item {
              id: circle
              x: root.width / 2
              y: root.height / 2
              property real percent: 0
              SequentialAnimation on percent {
                  id: circleAnim1
                  loops: Animation.Infinite
                  running: true
                  NumberAnimation {
                  duration: 12000
                  from: 0
                  to: 1
                  }

              }
          }

          Item {
              id: holder
              x: circle.x - Math.sin(circle.percent * root.twoPi) * root.radius - 50
              y: circle.y + Math.cos(circle.percent * root.twoPi) * root.radius + 50
          }

          Rectangle {
              color:"green"
              id: observer
              width: 16
              height: 16
              x: circle.x - width / 2
              y: circle.y - height / 2
          }
          Rectangle {
              color:"red"
              id: starship
              width: 32
              height: 32
              x: holder.x - width / 2
              y: holder.y - height / 2
          }
          MouseArea {
             anchors.fill: parent
             onClicked: {
                 audioEngine.sounds["effects"].play(Qt.vector3d(holder.x, holder.y, 0));
             }
          }

          SoundInstance {
              id: shipSound
              engine:audioEngine
              sound:"shipengine"
              position: Qt.vector3d(holder.x, holder.y, 0)
              direction: {
                  var a = (starship.rotation / 360) * root.twoPi;
                  return Qt.vector3d(Math.sin(a), -Math.cos(a), 0);
              }
              velocity: {
                  var speed = root.twoPi * root.radius / 4;
                  return shipSound.direction.times(speed);
              }

              Component.onCompleted: shipSound.play()
         }

          //Category Volume Control
          Rectangle {
              property variant volumeCtrl: audioEngine.categories["sfx"];
              id: volumeBar
              x: 10
              y: 10
              width: 280
              height: 22
              color: "darkgray"
              Rectangle {
                  id: volumeTracker
                  x: 0
                  y: 0
                  width: volumeBar.volumeCtrl.volume * parent.width;
                  height: parent.height
                  color: "lightgreen"
              }
              Text {
                  text: " volume:" + Math.round(volumeBar.volumeCtrl.volume * 100) +"%";
                  font.pointSize: 16;
                  font.italic: true;
                  color: "black"
                  anchors.fill: parent
              }

              MouseArea {
                  anchors.fill: parent
                  property bool m:false
                  onPressed: {
                      m = true;
                      updateVolume(mouse);
                  }
                  onReleased: {
                      m = false;
                  }

                  onPositionChanged: {
                      if (m) {
                          updateVolume(mouse);
                      }
                  }
                  function updateVolume(mouse) {
                      volumeBar.volumeCtrl.volume = Math.min(1, Math.max(0, mouse.x / (volumeBar.width - 1)));
                  }
              }
          }

          //Information display
          Item {
              x:10
              y:32
              Text {
                  text: " [live instances] = " + audioEngine.liveInstances;
                  font.pointSize: 14;
                  font.italic: true;
                  color: "black"
                  anchors.fill: parent
              }
          }

          Item {
              x:10
              y:60
              Text {
                  text: " [loading]=" + (audioEngine.loading ? "true" : "false");
                  font.pointSize: 16;
                  font.italic: true;
                  color: "black"
                  anchors.fill: parent
              }
          }
      }