<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Vektor</title>
<link rel="stylesheet" href="../css/style.css">
<script type="text/javascript" src="../../dist/paper-full.js"></script>
<script type="text/paperscript" canvas="canvas">
////////////////////////////////////////////////////////////////////////////////
// Interface
var values = {
fixLength: false,
fixAngle: false,
showCircle: false,
showAngleLength: true,
showCoordinates: false
};
////////////////////////////////////////////////////////////////////////////////
// Vector
var vectorStart, vector, vectorPrevious;
var vectorItem, items, dashedItems;
function processVector(event, drag) {
vector = event.point - vectorStart;
if (vectorPrevious) {
if (values.fixLength && values.fixAngle) {
vector = vectorPrevious;
} else if (values.fixLength) {
vector.length = vectorPrevious.length;
} else if (values.fixAngle) {
vector = vector.project(vectorPrevious);
}
}
drawVector(drag);
}
function drawVector(drag) {
if (items) {
for (var i = 0, l = items.length; i < l; i++) {
items[i].remove();
}
}
if (vectorItem)
vectorItem.remove();
items = [];
var arrowVector = vector.normalize(10);
var end = vectorStart + vector;
vectorItem = new Group(
new Path(vectorStart, end),
new Path(
end + arrowVector.rotate(135),
end,
end + arrowVector.rotate(-135)
)
);
vectorItem.strokeWidth = 0.75;
vectorItem.strokeColor = '#e4141b';
// Display:
dashedItems = [];
// Draw Circle
if (values.showCircle) {
dashedItems.push(new Path.Circle(vectorStart, vector.length));
}
// Draw Labels
if (values.showAngleLength) {
drawAngle(vectorStart, vector, !drag);
if (!drag)
drawLength(vectorStart, end, vector.angle < 0 ? -1 : 1, true);
}
var quadrant = vector.quadrant;
if (values.showCoordinates && !drag) {
drawLength(vectorStart, vectorStart + [vector.x, 0],
[1, 3].indexOf(quadrant) != -1 ? -1 : 1, true, vector.x, 'x: ');
drawLength(vectorStart, vectorStart + [0, vector.y],
[1, 3].indexOf(quadrant) != -1 ? 1 : -1, true, vector.y, 'y: ');
}
for (var i = 0, l = dashedItems.length; i < l; i++) {
var item = dashedItems[i];
item.strokeColor = 'black';
item.dashArray = [1, 2];
items.push(item);
}
// Update palette
values.x = vector.x;
values.y = vector.y;
values.length = vector.length;
values.angle = vector.angle;
}
function drawAngle(center, vector, label) {
var radius = 25, threshold = 10;
if (vector.length < radius + threshold || Math.abs(vector.angle) < 15)
return;
var from = new Point(radius, 0);
var through = from.rotate(vector.angle / 2);
var to = from.rotate(vector.angle);
var end = center + to;
dashedItems.push(new Path.Line(center,
center + new Point(radius + threshold, 0)));
dashedItems.push(new Path.Arc(center + from, center + through, end));
var arrowVector = to.normalize(7.5).rotate(vector.angle < 0 ? -90 : 90);
dashedItems.push(new Path([
end + arrowVector.rotate(135),
end,
end + arrowVector.rotate(-135)
]));
if (label) {
// Angle Label
var text = new PointText(center
+ through.normalize(radius + 10) + new Point(0, 3));
text.content = Math.floor(vector.angle * 100) / 100 + '\xb0';
items.push(text);
}
}
function drawLength(from, to, sign, label, value, prefix) {
var lengthSize = 5;
if ((to - from).length < lengthSize * 4)
return;
var vector = to - from;
var awayVector = vector.normalize(lengthSize).rotate(90 * sign);
var upVector = vector.normalize(lengthSize).rotate(45 * sign);
var downVector = upVector.rotate(-90 * sign);
var lengthVector = vector.normalize(
vector.length / 2 - lengthSize * Math.sqrt(2));
var line = new Path();
line.add(from + awayVector);
line.lineBy(upVector);
line.lineBy(lengthVector);
line.lineBy(upVector);
var middle = line.lastSegment.point;
line.lineBy(downVector);
line.lineBy(lengthVector);
line.lineBy(downVector);
dashedItems.push(line);
if (label) {
// Length Label
var textAngle = Math.abs(vector.angle) > 90
? textAngle = 180 + vector.angle : vector.angle;
// Label needs to move away by different amounts based on the
// vector's quadrant:
var away = (sign >= 0 ? [1, 4] : [2, 3]).indexOf(vector.quadrant) != -1
? 8 : 0;
var text = new PointText(middle + awayVector.normalize(away + lengthSize));
text.rotate(textAngle);
text.justification = 'center';
value = value || vector.length;
text.content = (prefix || '') + Math.floor(value * 1000) / 1000;
items.push(text);
}
}
////////////////////////////////////////////////////////////////////////////////
// Mouse Handling
var dashItem;
function onMouseDown(event) {
var end = vectorStart + vector;
var create = false;
if (event.modifiers.shift && vectorItem) {
vectorStart = end;
create = true;
} else if (vector && (event.modifiers.option
|| end && end.getDistance(event.point) < 10)) {
create = false;
} else {
vectorStart = event.point;
}
if (create) {
dashItem = vectorItem;
vectorItem = null;
}
processVector(event, true);
}
function onMouseDrag(event) {
if (!event.modifiers.shift && values.fixLength && values.fixAngle)
vectorStart = event.point;
processVector(event, event.modifiers.shift);
}
function onMouseUp(event) {
processVector(event, false);
if (dashItem) {
dashItem.dashArray = [1, 2];
dashItem = null;
}
vectorPrevious = vector;
}
</script>
</head>
<body>
<canvas id="canvas" resize></canvas>
</body>
</html>