Qt 5.8 | Qt Sensors | Qt Sensors Examples | Qt Sensors - Maze QML Example

Qt 5.8.0 Reference Documentation

# Qt Sensors - Maze QML Example

### 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
              var c = distance(mouse.x, mouse.y, newx, newy)
              var radians_to_degrees = 57.2957795

              if (a > 0)
                  angle = -Math.acos(a / b) * radians_to_degrees
              else
                  angle = -Math.asin(b / c) * radians_to_degrees
              if (b > 0)
                   angle = -Math.acos(a / c) * radians_to_degrees
              else
                  angle = Math.acos(a / c) * radians_to_degrees

              if (angle < 0)
                  angle = 360 + angle

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

Files:

- maze/Congratulation.qml
- maze/LabyrinthSquare.qml
- maze/Mouse.qml
- maze/lib.js
- maze/maze.qml
- maze/android/AndroidManifest.xml
- maze/components/ApplicationWindow.qml
- maze/components/Button.qml
- maze/main.cpp
- maze/maze.pro
- maze/maze.qrc