squircle.qml Example File | Qt Quick 5.12.9

- Qt 5.12
- Qt Quick
- Qt Quick Examples - Canvas
- squircle.qml Example File
- Qt 5.12.9 Reference Documentation

# squircle.qml Example File

canvas/squircle/squircle.qml

     /****************************************************************************
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     ** This file is part of the examples of the Qt Toolkit.
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     import QtQuick 2.0
     import "../contents"
     import "../../shared"

     Item {
         id: container
         width: 320
         height: 480

         Column {
             spacing: 6
             anchors.fill: parent
             anchors.topMargin: 12
             Text {
                 font.pointSize: 24
                 font.bold: true
                 text: "Squircles"
                 anchors.horizontalCenter: parent.horizontalCenter
                 color: "#777"
             }

             Image {
                 anchors.horizontalCenter: parent.horizontalCenter
                 source: "squircle.png"
                 width: 250
                 height: 25
             }

             Canvas {
                 id: canvas
                 width: 320
                 height: 250
                 antialiasing: true

                 property color strokeStyle: Qt.darker(fillStyle, 1.2)
                 property color fillStyle: "#6400aa"

                 property int lineWidth: 2
                 property int nSize: nCtrl.value
                 property real radius: rCtrl.value
                 property bool fill: true
                 property bool stroke: false
                 property real px: width/2
                 property real py: height/2 + 10
                 property real alpha: 1.0

                 onRadiusChanged: requestPaint();
                 onLineWidthChanged: requestPaint();
                 onNSizeChanged: requestPaint();
                 onFillChanged: requestPaint();
                 onStrokeChanged: requestPaint();

                 onPaint: squircle();

                 function squircle() {
                     var ctx = canvas.getContext("2d");
                     var N = canvas.nSize;
                     var R = canvas.radius;

                     N=Math.abs(N);
                     var M=N;
                     if (N>100) M=100;
                     if (N<0.00000000001) M=0.00000000001;

                     ctx.save();
                     ctx.globalAlpha =canvas.alpha;
                     ctx.fillStyle = "white";
                     ctx.fillRect(0, 0, canvas.width, canvas.height);

                     ctx.strokeStyle = canvas.strokeStyle;
                     ctx.fillStyle = canvas.fillStyle;
                     ctx.lineWidth = canvas.lineWidth;

                     ctx.beginPath();
                     var i = 0, x, y;
                     for (i=0; i<(2*R+1); i++){
                         x = Math.round(i-R) + canvas.px;
                         y = Math.round(Math.pow(Math.abs(Math.pow(R,M)-Math.pow(Math.abs(i-R),M)),1/M)) + canvas.py;

                         if (i == 0)
                             ctx.moveTo(x, y);
                         else
                             ctx.lineTo(x, y);
                     }

                     for (i=(2*R); i<(4*R+1); i++){
                         x =Math.round(3*R-i)+canvas.px;
                         y = Math.round(-Math.pow(Math.abs(Math.pow(R,M)-Math.pow(Math.abs(3*R-i),M)),1/M)) + canvas.py;
                         ctx.lineTo(x, y);
                     }
                     ctx.closePath();
                     if (canvas.stroke) {
                         ctx.stroke();
                     }

                     if (canvas.fill) {
                         ctx.fill();
                     }
                     ctx.restore();
                 }
             }

         }
         Column {
             anchors.bottom: parent.bottom
             anchors.bottomMargin: 12
             Slider {id: nCtrl ; min: 1 ; max: 10 ; init: 2 ; name: "N"}
             Slider {id: rCtrl ; min: 30 ; max: 180 ; init: 60 ; name: "Radius"}
         }
     }