- Author:
- David Nickerson <david.nickerson@gmail.com>
- Date:
- 2021-09-17 15:50:49+12:00
- Desc:
- tweak html formatting
- Permanent Source URI:
- https://models.fieldml.org/workspace/a1/rawfile/1b3862589abf79ae9119ee0b5e99a8b785d762e1/dojo-presentation/js/dojo/dojox/gfx/canvas.js
dojo.provide("dojox.gfx.canvas");
dojo.require("dojox.gfx._base");
dojo.require("dojox.gfx.shape");
dojo.require("dojox.gfx.path");
dojo.require("dojox.gfx.arc");
dojo.require("dojox.gfx.decompose");
dojo.experimental("dojox.gfx.canvas");
(function(){
var g = dojox.gfx, gs = g.shape, ga = g.arc,
m = g.matrix, mp = m.multiplyPoint, pi = Math.PI, twoPI = 2 * pi, halfPI = pi /2;
dojo.extend(g.Shape, {
_render: function(/* Object */ ctx){
// summary: render the shape
ctx.save();
this._renderTransform(ctx);
this._renderShape(ctx);
this._renderFill(ctx, true);
this._renderStroke(ctx, true);
ctx.restore();
},
_renderTransform: function(/* Object */ ctx){
if("canvasTransform" in this){
var t = this.canvasTransform;
ctx.translate(t.dx, t.dy);
ctx.rotate(t.angle2);
ctx.scale(t.sx, t.sy);
ctx.rotate(t.angle1);
// The future implementation when vendors catch up with the spec:
// var t = this.matrix;
// ctx.transform(t.xx, t.yx, t.xy, t.yy, t.dx, t.dy);
}
},
_renderShape: function(/* Object */ ctx){
// nothing
},
_renderFill: function(/* Object */ ctx, /* Boolean */ apply){
if("canvasFill" in this){
if("canvasFillImage" in this){
this.canvasFill = ctx.createPattern(this.canvasFillImage, "repeat");
delete this.canvasFillImage;
}
ctx.fillStyle = this.canvasFill;
if(apply){ ctx.fill(); }
}else{
ctx.fillStyle = "rgba(0,0,0,0.0)";
}
},
_renderStroke: function(/* Object */ ctx, /* Boolean */ apply){
var s = this.strokeStyle;
if(s){
ctx.strokeStyle = s.color.toString();
ctx.lineWidth = s.width;
ctx.lineCap = s.cap;
if(typeof s.join == "number"){
ctx.lineJoin = "miter";
ctx.miterLimit = s.join;
}else{
ctx.lineJoin = s.join;
}
if(apply){ ctx.stroke(); }
}else if(!apply){
ctx.strokeStyle = "rgba(0,0,0,0.0)";
}
},
// events are not implemented
getEventSource: function(){ return null; },
connect: function(){},
disconnect: function(){}
});
var modifyMethod = function(shape, method, extra){
var old = shape.prototype[method];
shape.prototype[method] = extra ?
function(){
this.surface.makeDirty();
old.apply(this, arguments);
extra.call(this);
return this;
} :
function(){
this.surface.makeDirty();
return old.apply(this, arguments);
};
};
modifyMethod(g.Shape, "setTransform",
function(){
// prepare Canvas-specific structures
if(this.matrix){
this.canvasTransform = g.decompose(this.matrix);
}else{
delete this.canvasTransform;
}
});
modifyMethod(g.Shape, "setFill",
function(){
// prepare Canvas-specific structures
var fs = this.fillStyle, f;
if(fs){
if(typeof(fs) == "object" && "type" in fs){
var ctx = this.surface.rawNode.getContext("2d");
switch(fs.type){
case "linear":
case "radial":
f = fs.type == "linear" ?
ctx.createLinearGradient(fs.x1, fs.y1, fs.x2, fs.y2) :
ctx.createRadialGradient(fs.cx, fs.cy, 0, fs.cx, fs.cy, fs.r);
dojo.forEach(fs.colors, function(step){
f.addColorStop(step.offset, g.normalizeColor(step.color).toString());
});
break;
case "pattern":
var img = new Image(fs.width, fs.height);
this.surface.downloadImage(img, fs.src);
this.canvasFillImage = img;
}
}else{
// Set fill color using CSS RGBA func style
f = fs.toString();
}
this.canvasFill = f;
}else{
delete this.canvasFill;
}
});
modifyMethod(g.Shape, "setStroke");
modifyMethod(g.Shape, "setShape");
dojo.declare("dojox.gfx.Group", g.Shape, {
// summary: a group shape (Canvas), which can be used
// to logically group shapes (e.g, to propagate matricies)
constructor: function(){
gs.Container._init.call(this);
},
_render: function(/* Object */ ctx){
// summary: render the group
ctx.save();
this._renderTransform(ctx);
this._renderFill(ctx);
this._renderStroke(ctx);
for(var i = 0; i < this.children.length; ++i){
this.children[i]._render(ctx);
}
ctx.restore();
}
});
dojo.declare("dojox.gfx.Rect", gs.Rect, {
// summary: a rectangle shape (Canvas)
_renderShape: function(/* Object */ ctx){
var s = this.shape, r = Math.min(s.r, s.height / 2, s.width / 2),
xl = s.x, xr = xl + s.width, yt = s.y, yb = yt + s.height,
xl2 = xl + r, xr2 = xr - r, yt2 = yt + r, yb2 = yb - r;
ctx.beginPath();
ctx.moveTo(xl2, yt);
if(r){
ctx.arc(xr2, yt2, r, -halfPI, 0, false);
ctx.arc(xr2, yb2, r, 0, halfPI, false);
ctx.arc(xl2, yb2, r, halfPI, pi, false);
ctx.arc(xl2, yt2, r, pi, halfPI, false);
}else{
ctx.lineTo(xr2, yt);
ctx.lineTo(xr, yb2);
ctx.lineTo(xl2, yb);
ctx.lineTo(xl, yt2);
}
ctx.closePath();
}
});
var bezierCircle = [];
(function(){
var u = ga.curvePI4;
bezierCircle.push(u.s, u.c1, u.c2, u.e);
for(var a = 45; a < 360; a += 45){
var r = m.rotateg(a);
bezierCircle.push(mp(r, u.c1), mp(r, u.c2), mp(r, u.e));
}
})();
dojo.declare("dojox.gfx.Ellipse", gs.Ellipse, {
// summary: an ellipse shape (Canvas)
setShape: function(){
g.Ellipse.superclass.setShape.apply(this, arguments);
// prepare Canvas-specific structures
var s = this.shape, t, c1, c2, r = [],
M = m.normalize([m.translate(s.cx, s.cy), m.scale(s.rx, s.ry)]);
t = mp(M, bezierCircle[0]);
r.push([t.x, t.y]);
for(var i = 1; i < bezierCircle.length; i += 3){
c1 = mp(M, bezierCircle[i]);
c2 = mp(M, bezierCircle[i + 1]);
t = mp(M, bezierCircle[i + 2]);
r.push([c1.x, c1.y, c2.x, c2.y, t.x, t.y]);
}
this.canvasEllipse = r;
return this;
},
_renderShape: function(/* Object */ ctx){
var r = this.canvasEllipse;
ctx.beginPath();
ctx.moveTo.apply(ctx, r[0]);
for(var i = 1; i < r.length; ++i){
ctx.bezierCurveTo.apply(ctx, r[i]);
}
ctx.closePath();
}
});
dojo.declare("dojox.gfx.Circle", gs.Circle, {
// summary: a circle shape (Canvas)
_renderShape: function(/* Object */ ctx){
var s = this.shape;
ctx.beginPath();
ctx.arc(s.cx, s.cy, s.r, 0, twoPI, 1);
}
});
dojo.declare("dojox.gfx.Line", gs.Line, {
// summary: a line shape (Canvas)
_renderShape: function(/* Object */ ctx){
var s = this.shape;
ctx.beginPath();
ctx.moveTo(s.x1, s.y1);
ctx.lineTo(s.x2, s.y2);
}
});
dojo.declare("dojox.gfx.Polyline", gs.Polyline, {
// summary: a polyline/polygon shape (Canvas)
setShape: function(){
g.Polyline.superclass.setShape.apply(this, arguments);
// dojo.inherited("setShape", arguments);
// prepare Canvas-specific structures
var p = this.shape.points, f = p[0], r = [], c, i;
if(p.length){
if(typeof f == "number"){
r.push(f, p[1]);
i = 2;
}else{
r.push(f.x, f.y);
i = 1;
}
for(; i < p.length; ++i){
c = p[i];
if(typeof c == "number"){
r.push(c, p[++i]);
}else{
r.push(c.x, c.y);
}
}
}
this.canvasPolyline = r;
return this;
},
_renderShape: function(/* Object */ ctx){
// console.debug("Polyline::_renderShape");
var p = this.canvasPolyline;
if(p.length){
ctx.beginPath();
ctx.moveTo(p[0], p[1]);
for(var i = 2; i < p.length; i += 2){
ctx.lineTo(p[i], p[i + 1]);
}
}
}
});
dojo.declare("dojox.gfx.Image", gs.Image, {
// summary: an image shape (Canvas)
setShape: function(){
g.Image.superclass.setShape.apply(this, arguments);
// prepare Canvas-specific structures
var img = new Image();
this.surface.downloadImage(img, this.shape.src);
this.canvasImage = img;
return this;
},
_renderShape: function(/* Object */ ctx){
var s = this.shape;
ctx.drawImage(this.canvasImage, s.x, s.y, s.width, s.height);
}
});
dojo.declare("dojox.gfx.Text", gs.Text, {
// summary: a text shape (Canvas)
_renderShape: function(/* Object */ ctx){
var s = this.shape;
// nothing for the moment
}
});
modifyMethod(g.Text, "setFont");
var pathRenderers = {
M: "_moveToA", m: "_moveToR",
L: "_lineToA", l: "_lineToR",
H: "_hLineToA", h: "_hLineToR",
V: "_vLineToA", v: "_vLineToR",
C: "_curveToA", c: "_curveToR",
S: "_smoothCurveToA", s: "_smoothCurveToR",
Q: "_qCurveToA", q: "_qCurveToR",
T: "_qSmoothCurveToA", t: "_qSmoothCurveToR",
A: "_arcTo", a: "_arcTo",
Z: "_closePath", z: "_closePath"
};
dojo.declare("dojox.gfx.Path", g.path.Path, {
// summary: a path shape (Canvas)
constructor: function(){
this.last = {};
this.lastControl = {};
},
setShape: function(){
this.canvasPath = [];
return g.Path.superclass.setShape.apply(this, arguments);
},
_updateWithSegment: function(segment){
var last = dojo.clone(this.last);
this[pathRenderers[segment.action]](this.canvasPath, segment.action, segment.args);
this.last = last;
g.Path.superclass._updateWithSegment.apply(this, arguments);
},
_renderShape: function(/* Object */ ctx){
var r = this.canvasPath;
ctx.beginPath();
for(var i = 0; i < r.length; i += 2){
ctx[r[i]].apply(ctx, r[i + 1]);
}
},
_moveToA: function(result, action, args){
result.push("moveTo", [args[0], args[1]]);
for(var i = 2; i < args.length; i += 2){
result.push("lineTo", [args[i], args[i + 1]]);
}
this.last.x = args[args.length - 2];
this.last.y = args[args.length - 1];
this.lastControl = {};
},
_moveToR: function(result, action, args){
if("x" in this.last){
result.push("moveTo", [this.last.x += args[0], this.last.y += args[1]]);
}else{
result.push("moveTo", [this.last.x = args[0], this.last.y = args[1]]);
}
for(var i = 2; i < args.length; i += 2){
result.push("lineTo", [this.last.x += args[i], this.last.y += args[i + 1]]);
}
this.lastControl = {};
},
_lineToA: function(result, action, args){
for(var i = 0; i < args.length; i += 2){
result.push("lineTo", [args[i], args[i + 1]]);
}
this.last.x = args[args.length - 2];
this.last.y = args[args.length - 1];
this.lastControl = {};
},
_lineToR: function(result, action, args){
for(var i = 0; i < args.length; i += 2){
result.push("lineTo", [this.last.x += args[i], this.last.y += args[i + 1]]);
}
this.lastControl = {};
},
_hLineToA: function(result, action, args){
for(var i = 0; i < args.length; ++i){
result.push("lineTo", [args[i], this.last.y]);
}
this.last.x = args[args.length - 1];
this.lastControl = {};
},
_hLineToR: function(result, action, args){
for(var i = 0; i < args.length; ++i){
result.push("lineTo", [this.last.x += args[i], this.last.y]);
}
this.lastControl = {};
},
_vLineToA: function(result, action, args){
for(var i = 0; i < args.length; ++i){
result.push("lineTo", [this.last.x, args[i]]);
}
this.last.y = args[args.length - 1];
this.lastControl = {};
},
_vLineToR: function(result, action, args){
for(var i = 0; i < args.length; ++i){
result.push("lineTo", [this.last.x, this.last.y += args[i]]);
}
this.lastControl = {};
},
_curveToA: function(result, action, args){
for(var i = 0; i < args.length; i += 6){
result.push("bezierCurveTo", args.slice(i, i + 6));
}
this.last.x = args[args.length - 2];
this.last.y = args[args.length - 1];
this.lastControl.x = args[args.length - 4];
this.lastControl.y = args[args.length - 3];
this.lastControl.type = "C";
},
_curveToR: function(result, action, args){
for(var i = 0; i < args.length; i += 6){
result.push("bezierCurveTo", [
this.last.x + args[i],
this.last.y + args[i + 1],
this.lastControl.x = this.last.x + args[i + 2],
this.lastControl.y = this.last.y + args[i + 3],
this.last.x + args[i + 4],
this.last.y + args[i + 5]
]);
this.last.x += args[i + 4];
this.last.y += args[i + 5];
}
this.lastControl.type = "C";
},
_smoothCurveToA: function(result, action, args){
for(var i = 0; i < args.length; i += 4){
var valid = this.lastControl.type == "C";
result.push("bezierCurveTo", [
valid ? 2 * this.last.x - this.lastControl.x : this.last.x,
valid ? 2 * this.last.y - this.lastControl.y : this.last.y,
args[i],
args[i + 1],
args[i + 2],
args[i + 3]
]);
this.lastControl.x = args[i];
this.lastControl.y = args[i + 1];
this.lastControl.type = "C";
}
this.last.x = args[args.length - 2];
this.last.y = args[args.length - 1];
},
_smoothCurveToR: function(result, action, args){
for(var i = 0; i < args.length; i += 4){
var valid = this.lastControl.type == "C";
result.push("bezierCurveTo", [
valid ? 2 * this.last.x - this.lastControl.x : this.last.x,
valid ? 2 * this.last.y - this.lastControl.y : this.last.y,
this.last.x + args[i],
this.last.y + args[i + 1],
this.last.x + args[i + 2],
this.last.y + args[i + 3]
]);
this.lastControl.x = this.last.x + args[i];
this.lastControl.y = this.last.y + args[i + 1];
this.lastControl.type = "C";
this.last.x += args[i + 2];
this.last.y += args[i + 3];
}
},
_qCurveToA: function(result, action, args){
for(var i = 0; i < args.length; i += 4){
result.push("quadraticCurveTo", args.slice(i, i + 4));
}
this.last.x = args[args.length - 2];
this.last.y = args[args.length - 1];
this.lastControl.x = args[args.length - 4];
this.lastControl.y = args[args.length - 3];
this.lastControl.type = "Q";
},
_qCurveToR: function(result, action, args){
for(var i = 0; i < args.length; i += 4){
result.push("quadraticCurveTo", [
this.lastControl.x = this.last.x + args[i],
this.lastControl.y = this.last.y + args[i + 1],
this.last.x + args[i + 2],
this.last.y + args[i + 3]
]);
this.last.x += args[i + 2];
this.last.y += args[i + 3];
}
this.lastControl.type = "Q";
},
_qSmoothCurveToA: function(result, action, args){
for(var i = 0; i < args.length; i += 2){
var valid = this.lastControl.type == "Q";
result.push("quadraticCurveTo", [
this.lastControl.x = valid ? 2 * this.last.x - this.lastControl.x : this.last.x,
this.lastControl.y = valid ? 2 * this.last.y - this.lastControl.y : this.last.y,
args[i],
args[i + 1]
]);
this.lastControl.type = "Q";
}
this.last.x = args[args.length - 2];
this.last.y = args[args.length - 1];
},
_qSmoothCurveToR: function(result, action, args){
for(var i = 0; i < args.length; i += 2){
var valid = this.lastControl.type == "Q";
result.push("quadraticCurveTo", [
this.lastControl.x = valid ? 2 * this.last.x - this.lastControl.x : this.last.x,
this.lastControl.y = valid ? 2 * this.last.y - this.lastControl.y : this.last.y,
this.last.x + args[i],
this.last.y + args[i + 1]
]);
this.lastControl.type = "Q";
this.last.x += args[i];
this.last.y += args[i + 1];
}
},
_arcTo: function(result, action, args){
var relative = action == "a";
for(var i = 0; i < args.length; i += 7){
var x1 = args[i + 5], y1 = args[i + 6];
if(relative){
x1 += this.last.x;
y1 += this.last.y;
}
var arcs = ga.arcAsBezier(
this.last, args[i], args[i + 1], args[i + 2],
args[i + 3] ? 1 : 0, args[i + 4] ? 1 : 0,
x1, y1
);
dojo.forEach(arcs, function(p){
result.push("bezierCurveTo", p);
});
this.last.x = x1;
this.last.y = y1;
}
this.lastControl = {};
},
_closePath: function(result, action, args){
result.push("closePath", []);
this.lastControl = {};
}
});
dojo.forEach(["moveTo", "lineTo", "hLineTo", "vLineTo", "curveTo",
"smoothCurveTo", "qCurveTo", "qSmoothCurveTo", "arcTo", "closePath"],
function(method){ modifyMethod(g.Path, method); }
);
dojo.declare("dojox.gfx.TextPath", g.path.TextPath, {
// summary: a text shape (Canvas)
_renderShape: function(/* Object */ ctx){
var s = this.shape;
// nothing for the moment
}
});
dojo.declare("dojox.gfx.Surface", gs.Surface, {
// summary: a surface object to be used for drawings (Canvas)
constructor: function(){
gs.Container._init.call(this);
this.pendingImageCount = 0;
this.makeDirty();
},
setDimensions: function(width, height){
// summary: sets the width and height of the rawNode
// width: String: width of surface, e.g., "100px"
// height: String: height of surface, e.g., "100px"
this.width = g.normalizedLength(width); // in pixels
this.height = g.normalizedLength(height); // in pixels
if(!this.rawNode) return this;
this.rawNode.width = width;
this.rawNode.height = height;
this.makeDirty();
return this; // self
},
getDimensions: function(){
// summary: returns an object with properties "width" and "height"
return this.rawNode ? {width: this.rawNode.width, height: this.rawNode.height} : null; // Object
},
_render: function(){
// summary: render the all shapes
if(this.pendingImageCount){ return; }
var ctx = this.rawNode.getContext("2d");
ctx.save();
ctx.clearRect(0, 0, this.rawNode.width, this.rawNode.height);
for(var i = 0; i < this.children.length; ++i){
this.children[i]._render(ctx);
}
ctx.restore();
if("pendingRender" in this){
clearTimeout(this.pendingRender);
delete this.pendingRender;
}
},
makeDirty: function(){
// summary: internal method, which is called when we may need to redraw
if(!this.pendingImagesCount && !("pendingRender" in this)){
this.pendingRender = setTimeout(dojo.hitch(this, this._render), 0);
}
},
downloadImage: function(img, url){
// summary:
// internal method, which starts an image download and renders, when it is ready
// img: Image:
// the image object
// url: String:
// the url of the image
var handler = dojo.hitch(this, this.onImageLoad);
if(!this.pendingImageCount++ && "pendingRender" in this){
clearTimeout(this.pendingRender);
delete this.pendingRender;
}
img.onload = handler;
img.onerror = handler;
img.onabort = handler;
img.src = url;
},
onImageLoad: function(){
if(!--this.pendingImageCount){ this._render(); }
},
// events are not implemented
getEventSource: function(){ return null; },
connect: function(){},
disconnect: function(){}
});
g.createSurface = function(parentNode, width, height){
// summary: creates a surface (Canvas)
// parentNode: Node: a parent node
// width: String: width of surface, e.g., "100px"
// height: String: height of surface, e.g., "100px"
if(!width){ width = "100%"; }
if(!height){ height = "100%"; }
var s = new g.Surface(),
p = dojo.byId(parentNode),
c = p.ownerDocument.createElement("canvas");
c.width = width;
c.height = height;
p.appendChild(c);
s.rawNode = c;
s.surface = s;
return s; // dojox.gfx.Surface
};
// Extenders
var C = gs.Container, Container = {
add: function(shape){
this.surface.makeDirty();
return C.add.apply(this, arguments);
},
remove: function(shape, silently){
this.surface.makeDirty();
return C.remove.apply(this, arguments);
},
clear: function(){
this.surface.makeDirty();
return C.clear.apply(this, arguments);
},
_moveChildToFront: function(shape){
this.surface.makeDirty();
return C._moveChildToFront.apply(this, arguments);
},
_moveChildToBack: function(shape){
this.surface.makeDirty();
return C._moveChildToBack.apply(this, arguments);
}
};
dojo.mixin(gs.Creator, {
// summary: Canvas shape creators
createObject: function(shapeType, rawShape) {
// summary: creates an instance of the passed shapeType class
// shapeType: Function: a class constructor to create an instance of
// rawShape: Object: properties to be passed in to the classes "setShape" method
// overrideSize: Boolean: set the size explicitly, if true
var shape = new shapeType();
shape.surface = this.surface;
shape.setShape(rawShape);
this.add(shape);
return shape; // dojox.gfx.Shape
}
});
dojo.extend(g.Group, Container);
dojo.extend(g.Group, gs.Creator);
dojo.extend(g.Surface, Container);
dojo.extend(g.Surface, gs.Creator);
})();
