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Qt Sensors - Maze QML Example

The Maze example demonstrates the TiltSensor QML type.

Maze in QML

To write a QML application that will use the TiltSensor QML sensors type you need to do the following steps:

Import the QtSensors 5.x declarative plugin:



  import QtSensors 5.0

Add the Sensor QML types into your qml file.

In this example we use the TiltSensor with values based in degrees and an accuracy of 5 degree:



      TiltSensor {
          id: tiltSensor
          active: true
      }

Starting the sensor can be done by setting the 'enabled' property to true:



          onTriggered: {
              if (!tiltSensor.enabled)
                  tiltSensor.active = true;

The mouse should move by a factor of the tilt value:



                  var xstep = 0;
                  xstep = tiltSensor.reading.yRotation * 0.1 //acceleration

                  var ystep = 0;
                  ystep = tiltSensor.reading.xRotation * 0.1 //acceleration

The walk direction of the mouse takes into account some collision detection:



                  if (xstep < 1 && xstep > 0)
                      xstep = 0
                  else if (xstep > -1 && xstep < 0)
                      xstep = 0

                  if (ystep < 1 && ystep > 0)
                      ystep = 0;
                  else if (ystep > -1 && ystep < 0)
                      ystep = 0;

                  if ((xstep < 0 && mouseCtrl.x > 0
                       && Lib.canMove(mouseCtrl.x + xstep,mouseCtrl.y))) {
                      xval = mouseCtrl.x + xstep;

                  } else if (xstep > 0 && mouseCtrl.x < (Lib.cellDimension * (Lib.dimension - 1))
                      && Lib.canMove(mouseCtrl.x + xstep,mouseCtrl.y)) {
                      xval = mouseCtrl.x + xstep;
                  } else
                      xval = mouseCtrl.x;

                  if (ystep < 0 && mouseCtrl.y > 0
                       && Lib.canMove(mouseCtrl.x, mouseCtrl.y + ystep)) {
                      yval = mouseCtrl.y + ystep;
                  } else if (ystep > 0 && (mouseCtrl.y < (Lib.cellDimension * (Lib.dimension - 1)))
                           && Lib.canMove(mouseCtrl.x, mouseCtrl.y + ystep)) {
                      yval = mouseCtrl.y + ystep;
                  } else
                      yval = mouseCtrl.y

                  mouseCtrl.move(xval, yval);

The rotation of the mouse image is determined according to the angle that the mouse is moving.



          var a = newy - mouse.y
          var b = newx - mouse.x
          angle = Math.atan2(-b, a) * mouse.radians_to_degrees
          if (angle < 0)
              angle = 360 + angle

          img.rotation = angle
          mouse.x = newx;
          mouse.y = newy;

Files:

Images:

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