| import clipRectangle from "../clip/rectangle.js"; |
| import identity from "../identity.js"; |
| import {transformer} from "../transform.js"; |
| import {fitExtent, fitSize, fitWidth, fitHeight} from "./fit.js"; |
| import {cos, degrees, radians, sin} from "../math.js"; |
|
|
| export default function() { |
| var k = 1, tx = 0, ty = 0, sx = 1, sy = 1, |
| alpha = 0, ca, sa, |
| x0 = null, y0, x1, y1, |
| kx = 1, ky = 1, |
| transform = transformer({ |
| point: function(x, y) { |
| var p = projection([x, y]) |
| this.stream.point(p[0], p[1]); |
| } |
| }), |
| postclip = identity, |
| cache, |
| cacheStream; |
|
|
| function reset() { |
| kx = k * sx; |
| ky = k * sy; |
| cache = cacheStream = null; |
| return projection; |
| } |
|
|
| function projection (p) { |
| var x = p[0] * kx, y = p[1] * ky; |
| if (alpha) { |
| var t = y * ca - x * sa; |
| x = x * ca + y * sa; |
| y = t; |
| } |
| return [x + tx, y + ty]; |
| } |
| projection.invert = function(p) { |
| var x = p[0] - tx, y = p[1] - ty; |
| if (alpha) { |
| var t = y * ca + x * sa; |
| x = x * ca - y * sa; |
| y = t; |
| } |
| return [x / kx, y / ky]; |
| }; |
| projection.stream = function(stream) { |
| return cache && cacheStream === stream ? cache : cache = transform(postclip(cacheStream = stream)); |
| }; |
| projection.postclip = function(_) { |
| return arguments.length ? (postclip = _, x0 = y0 = x1 = y1 = null, reset()) : postclip; |
| }; |
| projection.clipExtent = function(_) { |
| return arguments.length ? (postclip = _ == null ? (x0 = y0 = x1 = y1 = null, identity) : clipRectangle(x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1]), reset()) : x0 == null ? null : [[x0, y0], [x1, y1]]; |
| }; |
| projection.scale = function(_) { |
| return arguments.length ? (k = +_, reset()) : k; |
| }; |
| projection.translate = function(_) { |
| return arguments.length ? (tx = +_[0], ty = +_[1], reset()) : [tx, ty]; |
| } |
| projection.angle = function(_) { |
| return arguments.length ? (alpha = _ % 360 * radians, sa = sin(alpha), ca = cos(alpha), reset()) : alpha * degrees; |
| }; |
| projection.reflectX = function(_) { |
| return arguments.length ? (sx = _ ? -1 : 1, reset()) : sx < 0; |
| }; |
| projection.reflectY = function(_) { |
| return arguments.length ? (sy = _ ? -1 : 1, reset()) : sy < 0; |
| }; |
| projection.fitExtent = function(extent, object) { |
| return fitExtent(projection, extent, object); |
| }; |
| projection.fitSize = function(size, object) { |
| return fitSize(projection, size, object); |
| }; |
| projection.fitWidth = function(width, object) { |
| return fitWidth(projection, width, object); |
| }; |
| projection.fitHeight = function(height, object) { |
| return fitHeight(projection, height, object); |
| }; |
|
|
| return projection; |
| } |
|
|
