Warning, /maui/mauikit/src/controls.5/DoodleCanvas.qml is written in an unsupported language. File is not indexed.

 import QtQuick 2.13
 import QtQuick.Controls 2.13
 
 /*!
         *           \since org.mauikit.controls.labs 1.0
         *           \inqmlmodule org.mauikit.controls.labs
         */
 Item
 {
     id: control
     property alias buffer: buffer
 
     /**
             *
             */
     property int brushSize : 16
 
     /**
             *
             */
     property real brushOpacity : 1
 
     /**
             *
             */
     property int brushShape : 1 //0 -Circular, 1 - rectangular.
 
     /**
             *
             */
     property int maxBrushSize: 100
 
     /**
             *
             */
     property color paintColor: "red"
 
     Canvas
     {
         id: pickCanvas
         width: 1
         height: 1
         visible: false
     }
 
     Canvas
     {
         id: buffer
 
         anchors.fill: parent
 
         property real lastX
         property real lastY
         property color paintColor: control.paintColor
         smooth: false
 
         function clear()
         {
             var bufferCtx = buffer.getContext("2d")
             bufferCtx.clearRect(0, 0, width, height)
             buffer.requestPaint()
         }
 
         MouseArea
         {
             id: mouseArea
             anchors.fill: parent
             propagateComposedEvents: false
             preventStealing: true
 
             property int spacing: 32
 
             property real deltaDab: Math.max(spacing / 100 * control.brushSize, 1)
             property var points: []
             property point lastDrawPoint
             property point startPos
             property point finalPos
             property real brushAngle: 0
 
             onPressed:
             {
                 var point = Qt.point(mouseX, mouseY)
                 points = []
 
                 startPos = Qt.point(point.x, point.y)
                 finalPos = Qt.point(point.x, point.y)
                 lastDrawPoint = point
                 if (control.brushShape != 1)
                 {//if brush is not square
                     drawDab(point)
                 }
                 points = []
                 points.push(point)
 
                 //Hide Color Picker later move it to the whole screen.
                 //                 colorPicker.visible = false
             }
 
 
             onPositionChanged:
             {
 
                 drawDab(Qt.point(mouseX, mouseY))
 
                 // **************** Fancy and intense bezier I don't quite understand yet:
                 var currentPoint = Qt.point(mouseX, mouseY)
                 var startPoint = lastDrawPoint
 
 
                 //Rotating the dab if brush is recangular.
                 if (control.brushShape == 1) {
                     spacing = 16
 
                     if ( (currentPoint.x > startPoint.x))
                     {
                         // dab.brushAngle = find_angle(Qt.point(startPoint.x, startPoint.y-10),
                         // startPoint, currentPoint)
                         // dab.requestPaint()
                         brushAngle = find_angle(Qt.point(startPoint.x, startPoint.y-10),startPoint, currentPoint)
 
                     } else
                     {
                         // dab.brushAngle = - find_angle(Qt.point(startPoint.x, startPoint.y-10),
                         // startPoint, currentPoint)
                         // dab.requestPaint()
                         brushAngle = - find_angle(Qt.point(startPoint.x, startPoint.y-10),startPoint, currentPoint)
 
                     }
                 } else
                 {
                     spacing = 32
                 }
 
                 // ##
                 var currentSpacing = Math.sqrt(Math.pow(currentPoint.x - startPoint.x, 2) + Math.pow(currentPoint.y - startPoint.y, 2))
                 var numDabs = Math.floor(currentSpacing / deltaDab)
 
                 if (points.length == 1 || numDabs < 3) {
                     var endPoint = currentPoint
                 } else {
                     var controlPoint = points[points.length - 1]
                     endPoint = Qt.point((controlPoint.x + currentPoint.x) / 2, (controlPoint.y + currentPoint.y) / 2)
                 }
 
                 var deltaT = 1 / numDabs
                 var betweenPoint = startPoint
                 var t = deltaT
                 var diff
                 while (t > 0 && t <= 1) {
                     var point = bezierCurve(startPoint, controlPoint, endPoint, t)
                     var deltaPoint = Math.sqrt(Math.pow(point.x - betweenPoint.x, 2) + Math.pow(point.y - betweenPoint.y, 2))
                     // check on bezier loop
                     if (diff && Math.abs(deltaPoint - deltaDab) > Math.abs(diff)) { break; }
                     diff = deltaPoint - deltaDab
                     if (Math.abs(diff <= 0.5)) {
                         drawDab(point)
                         diff = undefined
                         betweenPoint = point
                         t += deltaT
                     } else {
                         t -= diff / deltaDab * deltaT
                     }
                 }
                 points.push(currentPoint)
                 lastDrawPoint = betweenPoint
 
             }
 
             onReleased:
             {
 
                 var bufferCtx = buffer.getContext("2d")
 
                 //saving image
                 // Grab Buffer image
                 var bufferImage = bufferCtx.getImageData(0, 0, width, height)
 
 
                 // Auto save painting
                 //                         saveDrawing()
 
                 // Clear the buffer
                 buffer.requestPaint()
 
 
             }
 
             function drawDab(point)
             {
                 var ctx = buffer.getContext("2d")
 
                 //Bezier Dab
                 // ctx.save()
                 // var size = toolbar.maxBrushSize //toolbar.brushSize
                 // var x = point.x - size / 2
                 // var y = point.y - size / 2
                 // if (x < startPos.x) { startPos.x = Math.min(0, x) }
                 // if (y < startPos.y) { startPos.y = Math.min(0, y) }
                 // if (x > finalPos.x) { finalPos.x = Math.max(x, buffer.width) }
                 // if (y > finalPos.y) { finalPos.y = Math.max(y, buffer.height) }
                 // ctx.drawImage(dab, x, y)
                 // ctx.restore()
                 // buffer.requestPaint()
 
                 //Raster Circle:
                 //ctx.drawImage("brushes/circle.png", x, y, size, size)
 
                 //Simple dab
                 var size = control.brushSize
                 ctx.fillStyle =  Qt.rgba(control.paintColor.r, control.paintColor.g, control.paintColor.b, control.brushOpacity);
                 var x = point.x - size / 2
                 var y = point.y - size / 2
 
                 if (control.brushShape == 0)
                 {
                     ctx.beginPath();
                     x = point.x - size/8
                     y = point.y - size/8
                     ctx.arc(x, y, size/2 ,0,Math.PI*2,true);
                 } else
                 {
                     ctx.save()
                     ctx.translate(x+size/2,y+size/2)
                     ctx.beginPath()
                     ctx.rotate(brushAngle)
                     ctx.roundedRect(-size/4, -size/8, size/2, size/4, 2, 2)
                     ctx.restore()
                 }
                 ctx.fill()
                 buffer.requestPaint()
 
             }
         }
 
 
     }
 
     // Bezier Curve
     function bezierCurve(start, control, end, t)
     {
         var x, y
         // linear bezier curve
         if (!control) {
             x = (1 - t) * start.x + t * end.x
             y = (1 - t) * start.y + t * end.y
         }
         // quad bezier curve
         else {
             x = Math.pow((1 - t), 2) * start.x + 2 * t * (1 - t) * control.x + t * t * end.x
             y = Math.pow((1 - t), 2) * start.y + 2 * t * (1 - t) * control.y + t * t * end.y
         }
         return Qt.point(x, y)
     }
 
     // Convert RGB to HEX
     function rgbToHex(r, g, b)
     {
         if (r > 255 || g > 255 || b > 255)
             throw "Invalid color component";
         return ((r << 16) | (g << 8) | b).toString(16);
     }
 
     function find_angle(A,B,C) {
         var AB = Math.sqrt(Math.pow(B.x-A.x,2)+ Math.pow(B.y-A.y,2));
         var BC = Math.sqrt(Math.pow(B.x-C.x,2)+ Math.pow(B.y-C.y,2));
         var AC = Math.sqrt(Math.pow(C.x-A.x,2)+ Math.pow(C.y-A.y,2));
         return Math.acos((BC*BC+AB*AB-AC*AC)/(2*BC*AB));
     }
 }