<!-- bezier clip visualizer -->
<html>
<head>
<div style="height:0">
<div id="clip1">
(gdb) p smaller
$2 = {{
x = 0.91292418204644155,
y = 0.41931201426549197
}, {
x = 0.70491388044579517,
y = 0.64754305977710236
}, {
x = 0,
y = 1
}}
(gdb) p larger
$3 = {{
x = 0.21875,
y = 0.765625
}, {
x = 0.125,
y = 0.875
}, {
x = 0,
y = 1
}}
(gdb) p distance2y
$1 = {{
x = 0,
y = 0.080355482722450078
}, {
x = 0.5,
y = 0.038383741101172597
}, {
x = 1,
y = 0
}}
</div>
<div id="quad21a">
bezier_clip q1=(0,0 1,0 0,2) q2=(0.5,0.25 0.5,0.5 0,1) minT=0 maxT=1
</div>
<div id="quad21b">
bezier_clip q1=(0.5,0.25 0.5,0.375 0.375,0.5625) q2=(0,0 1,0 0,2) minT=0.3 maxT=0.78125
</div>
<div id="quad21c">
bezier_clip q1=(0.42,0.18 0.6125,0.46875 0.341796875,1.22070312) q2=(0.5,0.25 0.5,0.375 0.375,0.5625) minT=0 maxT=0.926710098
</div>
<div id="quad21d">
bezier_clip q1=(0.5,0.25 0.5,0.307919381 0.473162762,0.379257381) q2=(0.42,0.18 0.6125,0.46875 0.341796875,1.22070312) minT=0.187231244 maxT=0.729263299
</div>
<div id="quad21e">
bezier_clip q1=(0.475846194,0.304363878 0.53317904,0.507883959 0.454423387,0.847492538) q2=(0.5,0.25 0.5,0.307919381 0.473162762,0.379257381) minT=0 maxT=1
</div>
<div id="quad21f">
bezier_clip q1=(0.493290691,0.311274036 0.486581381,0.343588381 0.473162762,0.379257381) q2=(0.475846194,0.304363878 0.53317904,0.507883959 0.454423387,0.847492538) minT=0.0828748517 maxT=0.150086861
</div>
<div id="quad21g">
(gdb) p smaller
$1 = {{
x = 0.48441440743366754,
y = 0.33903196011243797
}, {
x = 0.48750982503868118,
y = 0.35346899178071778
}, {
x = 0.48999046908865357,
y = 0.368520797004039
}}
(gdb) p larger
$2 = {{
x = 0.49329069058425024,
y = 0.31127403581536672
}, {
x = 0.48658138116850047,
y = 0.34358838107698753
}, {
x = 0.47316276233700094,
y = 0.37925738104648321
}}
</div>
<div id="quad36">
(gdb) p fQ
$2 = {{
x = 1.8883839294261275,
y = 2.1108590606904345
}, {
x = 1.888463903363252,
y = 2.1111576060205435
}, {
x = 1.8885438199983176,
y = 2.1114561800016824
}}
(gdb) p rh.fQ
$3 = {{
x = 1.8883839294260976,
y = 2.1108590606903377
}, {
x = 1.8886366953645748,
y = 2.1109850143489544
}, {
x = 1.8888888888888888,
y = 2.1111111111111112
}}
(gdb)
</div>
<div id="quad37">
{{x = 360.048828125, y = 229.2578125}, {x = 360.048828125, y = 224.4140625}, {x = 362.607421875, y = 221.3671875}}
{{x = 362.607421875, y = 221.3671875}, {x = 365.166015625, y = 218.3203125}, {x = 369.228515625, y = 218.3203125}}
</div>
<div id="quad38">
$2 = {{fX = 369.969421, fY = 137.94809}, {fX = 383.982849, fY = 121.260353}, {fX = 406.233154, fY = 121.260353}}
$4 = {{fX = 406.232788, fY = 121.260353}, {fX = 409.441956, fY = 121.260353}, {fX = 412.972046, fY = 121.795212}}
</div>
<div id="quad39">
{{x = 406.233154296875, y = 121.26035308837891}, {x = 406.23153587045397, y = 121.26035308837891}, {x = 406.22991748761177, y = 121.26035317666889}},
{{x = 406.23295158013377, y = 121.26035308872596}, {x = 406.2328698329315, y = 121.26035308837889}, {x = 406.2327880859375, y = 121.26035308837891}},
</div>
</div>
<script type="text/javascript">
var testDivs = [
quad56,
quad39,
quad38,
quad37,
quad36,
quad21g,
quad21a,
quad21b,
quad21c,
quad21d,
quad21e,
quad21f,
clip1,
];
var scale, columns, rows, xStart, yStart;
var ticks = 10;
var at_x = 13 + 0.5;
var at_y = 13 + 0.5;
var init_decimal_places = 1; // make this 3 to show more precision
var decimal_places;
var tests = [];
var testTitles = [];
var testIndex = 0;
var ctx;
var fat1 = true;
var fat2 = false;
var ctl1 = true;
var ctl2 = false;
var ctlPts1 = true;
var ctlPts2 = false;
var minScale = 1;
var subscale = 1;
function parse(test, title) {
var curveStrs = test.split("{{");
if (curveStrs.length == 1)
curveStrs = test.split("=(");
var pattern = /[a-z$=]?-?\d+\.*\d*/g;
var curves = [];
for (var c in curveStrs) {
var curveStr = curveStrs[c];
var points = curveStr.match(pattern);
var pts = [];
for (var wd in points) {
var num = parseFloat(points[wd]);
if (isNaN(num)) continue;
pts.push(num);
}
if (pts.length > 0)
curves.push(pts);
}
if (curves.length >= 2) {
tests.push(curves);
testTitles.push(title);
}
}
function init(test) {
var canvas = document.getElementById('canvas');
if (!canvas.getContext) return;
canvas.width = window.innerWidth - at_x;
canvas.height = window.innerHeight - at_y;
ctx = canvas.getContext('2d');
var xmin = Infinity;
var xmax = -Infinity;
var ymin = Infinity;
var ymax = -Infinity;
for (var curves in test) {
var curve = test[curves];
var last = curve.length;
for (var idx = 0; idx < last; idx += 2) {
xmin = Math.min(xmin, curve[idx]);
xmax = Math.max(xmax, curve[idx]);
ymin = Math.min(ymin, curve[idx + 1]);
ymax = Math.max(ymax, curve[idx + 1]);
}
}
subscale = 1;
decimal_places = init_decimal_places;
if (xmax != xmin && ymax != ymin) {
while ((xmax - xmin) * subscale < 0.1 && (ymax - ymin) * subscale < 0.1) {
subscale *= 10;
decimal_places += 1;
// if (subscale > 100000) {
// break;
// }
}
}
columns = Math.ceil(xmax * subscale) - Math.floor(xmin * subscale) + 1;
rows = Math.ceil(ymax * subscale) - Math.floor(ymin * subscale) + 1;
xStart = Math.floor(xmin * subscale) / subscale;
yStart = Math.floor(ymin * subscale) / subscale;
var hscale = ctx.canvas.width / columns / ticks;
var vscale = ctx.canvas.height / rows / ticks;
minScale = Math.floor(Math.min(hscale, vscale));
scale = minScale * subscale;
// while (columns < 1000 && rows < 1000) {
// columns *= 2;
// rows *= 2;
// }
}
function drawPoint(px, py, xoffset, yoffset, unit) {
var label = px.toFixed(decimal_places) + ", " + py.toFixed(decimal_places);
var _px = px * unit + xoffset;
var _py = py * unit + yoffset;
ctx.beginPath();
ctx.arc(_px, _py, 3, 0, Math.PI*2, true);
ctx.closePath();
ctx.fill();
ctx.fillText(label, _px + 5, _py);
}
function draw(test, title, _at_x, _at_y, scale) {
ctx.fillStyle = "rgba(0,0,0, 0.1)";
ctx.font = "normal 50px Arial";
ctx.fillText(title, 50, 50);
ctx.font = "normal 10px Arial";
var unit = scale * ticks;
ctx.lineWidth = 1;
var i;
for (i = 0; i <= rows * ticks; ++i) {
ctx.strokeStyle = (i % ticks) != 0 ? "rgb(160,160,160)" : "black";
ctx.beginPath();
ctx.moveTo(_at_x + 0, _at_y + i * minScale);
ctx.lineTo(_at_x + unit * columns, _at_y + i * minScale);
ctx.stroke();
}
for (i = 0; i <= columns * ticks; ++i) {
ctx.strokeStyle = (i % ticks) != 0 ? "rgb(160,160,160)" : "black";
ctx.beginPath();
ctx.moveTo(_at_x + i * minScale, _at_y + 0);
ctx.lineTo(_at_x + i * minScale, _at_y + unit * rows);
ctx.stroke();
}
var xoffset = xStart * -unit + _at_x;
var yoffset = yStart * -unit + _at_y;
ctx.fillStyle = "rgb(40,80,60)"
for (i = 0; i <= columns; i += (1 / ticks))
{
num = xStart + i / subscale;
ctx.fillText(num.toFixed(decimal_places), xoffset + num * unit - 5, 10);
}
for (i = 0; i <= rows; i += (1 / ticks))
{
num = yStart + i / subscale;
ctx.fillText(num.toFixed(decimal_places), 0, yoffset + num * unit + 0);
}
// draw curve 1 and 2
var curves, pts;
for (curves in test) {
var curve = test[curves];
ctx.beginPath();
ctx.moveTo(xoffset + curve[0] * unit, yoffset + curve[1] * unit);
switch (curve.length) {
case 6:
ctx.quadraticCurveTo(
xoffset + curve[2] * unit, yoffset + curve[3] * unit,
xoffset + curve[4] * unit, yoffset + curve[5] * unit);
break;
case 8:
ctx.bezierCurveTo(
xoffset + curve[2] * unit, yoffset + curve[3] * unit,
xoffset + curve[4] * unit, yoffset + curve[5] * unit,
xoffset + curve[6] * unit, yoffset + curve[7] * unit);
break;
}
if (curves == 2) ctx.strokeStyle = curves ? "red" : "blue";
ctx.stroke();
ctx.strokeStyle = "rgba(0,0,0, 0.3)";
ctx.beginPath();
ctx.moveTo(xoffset + curve[0] * unit, yoffset + curve[1] * unit);
ctx.lineTo(xoffset + curve[2] * unit, yoffset + curve[3] * unit);
ctx.lineTo(xoffset + curve[4] * unit, yoffset + curve[5] * unit);
if (curve.length == 8)
ctx.lineTo(xoffset + curve[6] * unit, yoffset + curve[7] * unit);
ctx.stroke();
}
// optionally draw fat lines for curve
if (fat1)
drawFat(test[0], xoffset, yoffset, unit);
if (fat2)
drawFat(test[1], xoffset, yoffset, unit);
if (ctl1)
drawCtl(test[0], xoffset, yoffset, unit);
if (ctl2)
drawCtl(test[1], xoffset, yoffset, unit);
if (ctlPts1)
drawCtlPts(test[0], xoffset, yoffset, unit);
if (ctlPts2)
drawCtlPts(test[1], xoffset, yoffset, unit);
}
function drawCtl(curve, xoffset, yoffset, unit) {
var last = curve.length - 2;
ctx.strokeStyle = "rgba(0,0,0, 0.5)";
ctx.beginPath();
ctx.moveTo(xoffset + curve[0] * unit, yoffset + curve[1] * unit);
ctx.lineTo(xoffset + curve[2] * unit, yoffset + curve[3] * unit);
ctx.lineTo(xoffset + curve[4] * unit, yoffset + curve[5] * unit);
ctx.stroke();
}
function drawCtlPts(curve, xoffset, yoffset, unit) {
drawPoint(curve[0], curve[1], xoffset, yoffset, unit);
drawPoint(curve[2], curve[3], xoffset, yoffset, unit);
drawPoint(curve[4], curve[5], xoffset, yoffset, unit);
}
function drawFat(curve, xoffset, yoffset, unit) {
var last = curve.length - 2;
ctx.strokeStyle = "rgba(0,0,0, 0.5)";
ctx.beginPath();
ctx.moveTo(xoffset + curve[0] * unit, yoffset + curve[1] * unit);
ctx.lineTo(xoffset + curve[last] * unit, yoffset + curve[last + 1] * unit);
ctx.stroke();
// draw line parallel to end points through control points
var dx = curve[last] - curve[0];
var dy = curve[last + 1] - curve[1];
drawParallelLine(curve[2], curve[3], dx, dy, xoffset, yoffset, unit);
if (curve.length == 8)
drawParallelLine(curve[4], curve[5], dx, dy, xoffset, yoffset, unit);
}
function drawParallelLine(x, y, dx, dy, xoffset, yoffset, unit) {
var x1 = x - dx;
var y1 = y - dy;
var x2 = x + dx;
var y2 = y + dy;
ctx.beginPath();
ctx.moveTo(xoffset + x1 * unit, yoffset + y1 * unit);
ctx.lineTo(xoffset + x2 * unit, yoffset + y2 * unit);
ctx.stroke();
}
function drawTop() {
init(tests[testIndex]);
redraw();
}
function redraw() {
ctx.beginPath();
ctx.rect(0, 0, ctx.canvas.width, ctx.canvas.height);
ctx.fillStyle="white";
ctx.fill();
draw(tests[testIndex], testTitles[testIndex], at_x, at_y, scale);
}
function doKeyPress(evt) {
var char = String.fromCharCode(evt.charCode);
switch (char) {
case 'c':
ctl2 ^= true;
if (ctl2 == false)
ctl1 ^= true;
drawTop();
break;
case 'd':
ctlPts2 ^= true;
if (ctlPts2 == false)
ctlPts1 ^= true;
drawTop();
break;
case 'f':
fat2 ^= true;
if (fat2 == false)
fat1 ^= true;
drawTop();
break;
case 'N':
testIndex += 9;
case 'n':
if (++testIndex >= tests.length)
testIndex = 0;
mouseX = Infinity;
drawTop();
break;
case 'P':
testIndex -= 9;
case 'p':
if (--testIndex < 0)
testIndex = tests.length - 1;
mouseX = Infinity;
drawTop();
break;
}
}
function handleMouseClick() {
}
function handleMouseOver() {
}
function start() {
for (i = 0; i < testDivs.length; ++i) {
var title = testDivs[i].id.toString();
var str = testDivs[i].firstChild.data;
parse(str, title);
}
drawTop();
window.addEventListener('keypress', doKeyPress, true);
window.onresize = function() {
drawTop();
}
}
</script>
</head>
<body onLoad="start();">
<canvas id="canvas" width="750" height="500"
onmousemove="handleMouseOver()"
onclick="handleMouseClick()"
></canvas >
</body>
</html>