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import QtQuick 2.0
Item {
id: view
property alias fillColor: rectangle.color
property alias border: rectangle.border
property var strokes: []
property bool autoRepaint: true
property alias canvas: canvas
function _drawStroke(ctx, stroke) {
var points = stroke.points;
ctx.save();
ctx.lineWidth = stroke.lineWidth;
ctx.strokeStyle = stroke.lineColor;
ctx.lineCap = 'round';
ctx.lineJoin = 'round';
ctx.beginPath();
ctx.moveTo(points[0].x, points[0].y);
for (var i = 1; i < points.length; i++) {
ctx.lineTo(points[i].x, points[i].y);
}
ctx.stroke();
ctx.restore();
}
function _intersect(r1, r2) {
if (!r1.width || !r2.width) return false;
if (!r1.height || !r2.height) return false;
if (r1.x >= r2.x + r2.width) return false;
if (r1.y >= r2.y + r2.height) return false;
if (r2.x >= r1.x + r1.width) return false;
if (r2.y >= r1.y + r1.height) return false;
return true;
}
Rectangle {
id: rectangle
anchors.fill: parent
color: Qt.rgba(1.0, 1.0, 1.0, 0.3)
radius: 10.0
}
Canvas {
id: canvas
anchors.fill: parent
renderTarget: Canvas.Image
renderStrategy: Canvas.Immediate
onPaint: {
var ctx = canvas.getContext('2d');
ctx.clearRect(region.x, region.y, region.width, region.height);
ctx.save();
ctx.beginPath();
ctx.rect(region.x, region.y, region.width, region.height);
ctx.clip();
for (var i = 0; i < strokes.length; i++) {
if (_intersect(region, strokes[i].boundingBox)) {
_drawStroke(ctx, strokes[i]);
}
}
ctx.restore();
}
}
onStrokesChanged: {
if (autoRepaint) {
canvas.requestPaint();
}
}
}
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