104 lines
2.7 KiB
JavaScript
104 lines
2.7 KiB
JavaScript
|
|
||
|
|
var Line = function() {
|
||
|
|
|
||
|
|
var pair = function(a,b) { return [a,b]; };
|
||
|
|
|
||
|
|
var create = function(center, ps, theta, s) {
|
||
|
|
return { center: center, points: ps, theta: theta, scale: s };
|
||
|
|
};
|
||
|
|
|
||
|
|
|
||
|
|
//// Construction ////
|
||
|
|
|
||
|
|
var line = function(ps) {
|
||
|
|
var parr = [];
|
||
|
|
while (ps[0] === "Cons") {
|
||
|
|
parr.push(pair(ps[1][1], ps[1][2]));
|
||
|
|
ps = ps[2];
|
||
|
|
}
|
||
|
|
return create(pair(0,0), parr, 0, 1);
|
||
|
|
};
|
||
|
|
|
||
|
|
//// Atomize ////
|
||
|
|
|
||
|
|
var solid = function(color) { return function(line) { return function(ctx) {
|
||
|
|
ctx.save();
|
||
|
|
ctx.beginPath();
|
||
|
|
ctx.translate(line.center[0], line.center[1]);
|
||
|
|
ctx.rotate(line.theta);
|
||
|
|
ctx.scale(line.scale, line.scale);
|
||
|
|
var points = line.points;
|
||
|
|
var i = points.length;
|
||
|
|
ctx.moveTo(points[i-1][0], points[i-1][1]);
|
||
|
|
while (i--) {
|
||
|
|
ctx.lineTo(points[i][0], points[i][1]);
|
||
|
|
}
|
||
|
|
ctx.strokeStyle = Color.Internal.extract(color);
|
||
|
|
ctx.stroke();
|
||
|
|
ctx.restore();
|
||
|
|
return ctx;
|
||
|
|
};
|
||
|
|
};
|
||
|
|
};
|
||
|
|
|
||
|
|
var customLine = function(pattern) {
|
||
|
|
return function(color) { return function(line) {
|
||
|
|
if (typeof pattern[0] === "string") {
|
||
|
|
var temp = [];
|
||
|
|
while (pattern[0] === "Cons") {
|
||
|
|
temp.push(pattern[1]);
|
||
|
|
pattern = pattern[2];
|
||
|
|
}
|
||
|
|
pattern = temp;
|
||
|
|
}
|
||
|
|
if (pattern.length === 0) { pattern = [8,4]; }
|
||
|
|
return function(ctx) {
|
||
|
|
ctx.save();
|
||
|
|
ctx.beginPath();
|
||
|
|
ctx.translate(line.center[0], line.center[1]);
|
||
|
|
ctx.rotate(line.theta);
|
||
|
|
ctx.scale(line.scale, line.scale);
|
||
|
|
customLineHelp(ctx, pattern, line.points);
|
||
|
|
ctx.strokeStyle = Color.Internal.extract(color);
|
||
|
|
ctx.stroke();
|
||
|
|
ctx.restore();
|
||
|
|
return ctx;
|
||
|
|
};
|
||
|
|
};
|
||
|
|
};
|
||
|
|
};
|
||
|
|
var customLineHelp = function(ctx, pattern, points) {
|
||
|
|
var i = points.length - 1;
|
||
|
|
var x0 = points[i][0], y0 = points[i][1];
|
||
|
|
var x1=0, y1=0, dx=0, dy=0, remaining=0, nx=0, ny=0;
|
||
|
|
var pindex = 0, plen = pattern.length;
|
||
|
|
var draw = true, segmentLength = pattern[0];
|
||
|
|
ctx.moveTo(x0,y0);
|
||
|
|
while (i--) {
|
||
|
|
x1 = points[i][0]; y1 = points[i][1];
|
||
|
|
dx = x1 - x0; dy = y1 - y0;
|
||
|
|
remaining = Math.sqrt(dx * dx + dy * dy);
|
||
|
|
while (segmentLength <= remaining) {
|
||
|
|
x0 += dx * segmentLength / remaining;
|
||
|
|
y0 += dy * segmentLength / remaining;
|
||
|
|
ctx[draw ? 'lineTo' : 'moveTo'](x0, y0);
|
||
|
|
// update starting position
|
||
|
|
dx = x1 - x0; dy = y1 - y0;
|
||
|
|
remaining = Math.sqrt(dx * dx + dy * dy);
|
||
|
|
// update pattern
|
||
|
|
draw = !draw;
|
||
|
|
pindex = (pindex + 1) % plen;
|
||
|
|
segmentLength = pattern[pindex];
|
||
|
|
}
|
||
|
|
if (remaining > 0) {
|
||
|
|
ctx[draw ? 'lineTo' : 'moveTo'](x1, y1);
|
||
|
|
segmentLength -= remaining;
|
||
|
|
}
|
||
|
|
x0 = x1; y0 = y1;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
return {line:line, customLine:customLine, solid:solid,
|
||
|
|
dashed: customLine([8,4]), dotted: customLine([3,3]) };
|
||
|
|
}();
|