Qt 5.6 | Qt Quick | Qt Quick Particles Examples - Emitters | customemitter.qml Example File

Qt 5.6.3 Reference Documentation

# customemitter.qml Example File

particles/emitters/content/customemitter.qml

      /****************************************************************************
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      ** Copyright (C) 2015 The Qt Company Ltd.
      ** Contact: http://www.qt.io/licensing/
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      ** This file is part of the examples of the Qt Toolkit.
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      import QtQuick 2.0
      import QtQuick.Particles 2.0

      ParticleSystem {
          id: sys
          width: 360
          height: 600
          running: true
          Rectangle {
              z: -1
              anchors.fill: parent
              color: "black"
          }

          property real petalLength: 180
          property real petalRotation: 0
          NumberAnimation on petalRotation {
              from: 0;
              to: 360;
              loops: -1;
              running: true
              duration: 24000
          }

          function convert(a) {return a*(Math.PI/180);}
          Emitter {
              lifeSpan: 4000
              emitRate: 120
              size: 12
              anchors.centerIn: parent
              onEmitParticles: {
                  for (var i=0; i<particles.length; i++) {
                      var particle = particles[i];
                      particle.startSize = Math.max(02,Math.min(492,Math.tan(particle.t/2)*24));
                      var theta = Math.floor(Math.random() * 6.0);
                      particle.red = theta == 0 || theta == 1 || theta == 2 ? 0.2 : 1;
                      particle.green = theta == 2 || theta == 3 || theta == 4 ? 0.2 : 1;
                      particle.blue = theta == 4 || theta == 5 || theta == 0 ? 0.2 : 1;
                      theta /= 6.0;
                      theta *= 2.0*Math.PI;
                      theta += sys.convert(sys.petalRotation);//Convert from degrees to radians
                      particle.initialVX = petalLength * Math.cos(theta);
                      particle.initialVY = petalLength * Math.sin(theta);
                      particle.initialAX = particle.initialVX * -0.5;
                      particle.initialAY = particle.initialVY * -0.5;
                  }
              }
          }

          ImageParticle {
              source: "qrc:///particleresources/fuzzydot.png"
              alpha: 0.0
          }
      }