squircle.qml Example File

canvas/squircle/squircle.qml
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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"} } }