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/******************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd
** All rights reserved.
** For any questions to The Qt Company, please use contact form at http://qt.io
**
** This file is part of the Qt Virtual Keyboard module.
**
** Licensees holding valid commercial license for Qt may use this file in
** accordance with the Qt License Agreement provided with the Software
** or, alternatively, in accordance with the terms contained in a written
** agreement between you and The Qt Company.
**
** If you have questions regarding the use of this file, please use
** contact form at http://qt.io
**
******************************************************************************/
.pragma library
function renderSmoothedLine(ctx, trace, renderPos) {
if (!trace)
return renderPos
if (renderPos >= trace.length)
return renderPos
// Fetch points and draw the initial "dot"
var points, tp
if (renderPos === 0) {
points = trace.points()
tp = points[renderPos++]
ctx.beginPath()
ctx.moveTo(tp.x, tp.y)
ctx.lineTo(tp.x, tp.y + 0.000001)
ctx.stroke()
} else {
points = trace.points(renderPos - 1)
}
// Draw smoothed line using quadratic curve
var i = 1
if (i + 1 < points.length) {
var pt1, pt2
if (renderPos === 1) {
tp = points[i - 1]
} else {
pt1 = points[i - 1]
pt2 = points[i]
tp = Qt.point((pt1.x + pt2.x) / 2, (pt1.y + pt2.y) / 2)
}
ctx.beginPath()
ctx.moveTo(tp.x, tp.y)
while (i + 1 < points.length) {
pt1 = points[i++]
pt2 = points[i]
tp = Qt.point((pt1.x + pt2.x) / 2, (pt1.y + pt2.y) / 2)
ctx.quadraticCurveTo(pt1.x, pt1.y, tp.x, tp.y)
}
}
// Draw the remainder of the line
if (trace.isFinal) {
if (i < points.length) {
tp = points[i++]
ctx.lineTo(tp.x, tp.y)
}
}
if (i > 1)
ctx.stroke()
return renderPos + i - 1
}
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