Qt Sensors - Maze QML Example

../_images/maze.png

Maze in QML

The Maze example demonstrates the TiltSensor QML type.

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;

Example project @ code.qt.io