This plugin is a fork of d3-zoom that adds several features by separating scaling on x and y:
Scale independently along x-axis and y-axis
Constrain scale extent on zoom out to respect translate extent constraints
Apply "scale factor ratio" on user input. For instance, with a scale ratio of 0.5 on x-axis and 1 on y-axis, when user zoom with its mouse, the increase of scale factor on x-axis will only be half of the increase on y-axis.
| (function (global, factory) { | |
| typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('d3-dispatch'), require('d3-drag'), require('d3-interpolate'), require('d3-selection'), require('d3-transition')) : | |
| typeof define === 'function' && define.amd ? define(['exports', 'd3-dispatch', 'd3-drag', 'd3-interpolate', 'd3-selection', 'd3-transition'], factory) : | |
| (factory((global.d3 = global.d3 || {}),global.d3,global.d3,global.d3,global.d3,global.d3)); | |
| }(this, function (exports,d3Dispatch,d3Drag,d3Interpolate,d3Selection,d3Transition) { 'use strict'; | |
| function constant(x) { | |
| return function() { | |
| return x; | |
| }; | |
| } | |
| function ZoomEvent(target, type, transform) { | |
| this.target = target; | |
| this.type = type; | |
| this.transform = transform; | |
| } | |
| function Transform(x, y, kx, ky) { | |
| this.kx = kx; | |
| this.ky = ky || kx; | |
| this.x = x; | |
| this.y = y; | |
| } | |
| Transform.prototype = { | |
| constructor: Transform, | |
| scale: function(kx, ky) { | |
| ky = ky === undefined ? kx : ky; | |
| return kx === 1 && (!ky || ky === 1) ? this : new Transform(this.x, this.y, this.kx * kx, this.ky * ky); | |
| }, | |
| translate: function(x, y) { | |
| return x === 0 & y === 0 ? this : new Transform(this.x + this.kx * x, this.y + this.ky * y, this.kx, this.ky); | |
| }, | |
| apply: function(point) { | |
| return [point[0] * this.kx + this.x, point[1] * this.ky + this.y]; | |
| }, | |
| applyX: function(x) { | |
| return x * this.kx + this.x; | |
| }, | |
| applyY: function(y) { | |
| return y * this.ky + this.y; | |
| }, | |
| invert: function(location) { | |
| return [(location[0] - this.x) / this.kx, (location[1] - this.y) / this.ky]; | |
| }, | |
| invertX: function(x) { | |
| return (x - this.x) / this.kx; | |
| }, | |
| invertY: function(y) { | |
| return (y - this.y) / this.ky; | |
| }, | |
| rescaleX: function(x) { | |
| return x.copy().domain(x.range().map(this.invertX, this).map(x.invert, x)); | |
| }, | |
| rescaleY: function(y) { | |
| return y.copy().domain(y.range().map(this.invertY, this).map(y.invert, y)); | |
| }, | |
| toString: function() { | |
| return "translate(" + this.x + "," + this.y + ") scale(" + this.kx + "," + this.ky + ")"; | |
| } | |
| }; | |
| var identity = new Transform(0, 0, 1, 1); | |
| transform.prototype = Transform.prototype; | |
| function transform(node) { | |
| return node.__zoom || identity; | |
| } | |
| function nopropagation() { | |
| d3Selection.event.stopImmediatePropagation(); | |
| } | |
| function noevent() { | |
| d3Selection.event.preventDefault(); | |
| d3Selection.event.stopImmediatePropagation(); | |
| } | |
| // Ignore right-click, since that should open the context menu. | |
| function defaultFilter() { | |
| return !d3Selection.event.button; | |
| } | |
| function defaultExtent() { | |
| var e = this, w, h; | |
| if (e instanceof SVGElement) { | |
| e = e.ownerSVGElement || e; | |
| w = e.width.baseVal.value; | |
| h = e.height.baseVal.value; | |
| } else { | |
| if (e && e.clientWidth && e.clientHeight) { | |
| w = e.clientWidth; | |
| h = e.clientHeight; | |
| } else { | |
| throw 'd3-xyzoom failed to constrain scales because extent is undefined.'; | |
| } | |
| } | |
| return [[0, 0], [w, h]]; | |
| } | |
| function defaultTransform() { | |
| return this.__zoom || identity; | |
| } | |
| function zoom() { | |
| var filter = defaultFilter, | |
| extent = defaultExtent, | |
| kx0 = 0, | |
| ky0 = 0, | |
| kx1 = Infinity, | |
| ky1 = Infinity, | |
| rx = 1, | |
| ry = 1, | |
| x0 = -Infinity, | |
| x1 = Infinity, | |
| y0 = -Infinity, | |
| y1 = Infinity, | |
| duration = 250, | |
| interpolate = d3Interpolate.interpolateNumber, | |
| gestures = [], | |
| listeners = d3Dispatch.dispatch("start", "zoom", "end"), | |
| touchstarting, | |
| touchending, | |
| touchDelay = 500, | |
| wheelDelay = 150; | |
| function zoom(selection) { | |
| selection | |
| .on("wheel.zoom", wheeled) | |
| .on("mousedown.zoom", mousedowned) | |
| .on("dblclick.zoom", dblclicked) | |
| .on("touchstart.zoom", touchstarted) | |
| .on("touchmove.zoom", touchmoved) | |
| .on("touchend.zoom touchcancel.zoom", touchended) | |
| .style("-webkit-tap-highlight-color", "rgba(0,0,0,0)") | |
| .property("__zoom", defaultTransform); | |
| } | |
| zoom.transform = function(collection, transform) { | |
| var selection = collection.selection ? collection.selection() : collection; | |
| selection.property("__zoom", defaultTransform); | |
| if (collection !== selection) { | |
| schedule(collection, transform); | |
| } else { | |
| selection.interrupt().each(function() { | |
| gesture(this, arguments) | |
| .start() | |
| .zoom(null, typeof transform === "function" ? transform.apply(this, arguments) : transform) | |
| .end(); | |
| }); | |
| } | |
| }; | |
| zoom.scaleBy = function(selection, kx, ky) { | |
| zoom.scaleTo(selection, function() { | |
| var k0 = this.__zoom.kx, | |
| k1 = typeof kx === "function" ? kx.apply(this, arguments) : kx; | |
| return k0 * k1; | |
| }, function() { | |
| var k0 = this.__zoom.ky, | |
| k1 = typeof ky === "function" ? ky.apply(this, arguments) : ky; | |
| return k0 * k1; | |
| }); | |
| }; | |
| zoom.scaleTo = function(selection, kx, ky) { | |
| zoom.transform(selection, function() { | |
| var e = extent.apply(this, arguments), | |
| t0 = this.__zoom, | |
| p0 = centroid(e), | |
| p1 = t0.invert(p0), | |
| kx1 = typeof kx === "function" ? kx.apply(this, arguments) : kx, | |
| ky1 = typeof ky === "function" ? ky.apply(this, arguments) : ky; | |
| return constrain(translate(scale(t0, kx1, ky1), p0, p1), e); | |
| }); | |
| }; | |
| zoom.translateBy = function(selection, x, y) { | |
| zoom.transform(selection, function() { | |
| return constrain(this.__zoom.translate( | |
| typeof x === "function" ? x.apply(this, arguments) : x, | |
| typeof y === "function" ? y.apply(this, arguments) : y | |
| ), extent.apply(this, arguments)); | |
| }); | |
| }; | |
| function scale(transform, kx, ky) { | |
| kx = Math.max(kx0, Math.min(kx1, kx)); | |
| ky = Math.max(ky0, Math.min(ky1, ky)); | |
| return (kx === transform.kx && ky === transform.ky) ? transform : new Transform(transform.x, transform.y, kx, ky); | |
| } | |
| function translate(transform, p0, p1) { | |
| var x = p0[0] - p1[0] * transform.kx, y = p0[1] - p1[1] * transform.ky; | |
| return x === transform.x && y === transform.y ? transform : new Transform(x, y, transform.kx, transform.ky); | |
| } | |
| function constrain(transform, extent) { | |
| var dx0 = transform.invertX(extent[0][0]) - x0, | |
| dx1 = transform.invertX(extent[1][0]) - x1, | |
| dy0 = transform.invertY(extent[0][1]) - y0, | |
| dy1 = transform.invertY(extent[1][1]) - y1; | |
| return transform.translate( | |
| dx1 > dx0 ? (dx0 + dx1) / 2 : Math.min(0, dx0) || Math.max(0, dx1), | |
| dy1 > dy0 ? (dy0 + dy1) / 2 : Math.min(0, dy0) || Math.max(0, dy1) | |
| ); | |
| } | |
| function centroid(extent) { | |
| return [(+extent[0][0] + +extent[1][0]) / 2, (+extent[0][1] + +extent[1][1]) / 2]; | |
| } | |
| function schedule(transition, transform) { | |
| transition | |
| .on("start.zoom", function() { gesture(this, arguments).start(); }) | |
| .on("interrupt.zoom end.zoom", function() { gesture(this, arguments).end(); }) | |
| .tween("zoom", function() { | |
| var that = this, | |
| args = arguments, | |
| g = gesture(that, args), | |
| a = that.__zoom, | |
| b = typeof transform === "function" ? transform.apply(that, args) : transform; | |
| var txi = interpolate(a.x, b.x); | |
| var tyi = interpolate(a.y, b.y); | |
| var kxi = interpolate(a.kx, b.kx); | |
| var kyi = interpolate(a.ky, b.ky); | |
| return function(t) { | |
| if (t === 1) t = b; // Avoid rounding error on end. | |
| else { | |
| t = new Transform(txi(t), tyi(t), kxi(t), kyi(t)); | |
| } | |
| g.zoom(null, t); | |
| }; | |
| }); | |
| } | |
| function gesture(that, args) { | |
| for (var i = 0, n = gestures.length, g; i < n; ++i) { | |
| if ((g = gestures[i]).that === that) { | |
| return g; | |
| } | |
| } | |
| return new Gesture(that, args); | |
| } | |
| function Gesture(that, args) { | |
| this.that = that; | |
| this.args = args; | |
| this.index = -1; | |
| this.active = 0; | |
| this.extent = extent.apply(that, args); | |
| } | |
| Gesture.prototype = { | |
| start: function() { | |
| if (++this.active === 1) { | |
| this.index = gestures.push(this) - 1; | |
| this.emit("start"); | |
| } | |
| return this; | |
| }, | |
| zoom: function(key, transform) { | |
| if (this.mouse && key !== "mouse") this.mouse[1] = transform.invert(this.mouse[0]); | |
| if (this.touch0 && key !== "touch") this.touch0[1] = transform.invert(this.touch0[0]); | |
| if (this.touch1 && key !== "touch") this.touch1[1] = transform.invert(this.touch1[0]); | |
| this.that.__zoom = transform; | |
| this.emit("zoom"); | |
| return this; | |
| }, | |
| end: function() { | |
| if (--this.active === 0) { | |
| gestures.splice(this.index, 1); | |
| this.index = -1; | |
| this.emit("end"); | |
| } | |
| return this; | |
| }, | |
| emit: function(type) { | |
| d3Selection.customEvent(new ZoomEvent(zoom, type, this.that.__zoom), listeners.apply, listeners, [type, this.that, this.args]); | |
| } | |
| }; | |
| function wheeled() { | |
| if (!filter.apply(this, arguments)) return; | |
| var g = gesture(this, arguments); | |
| var t = this.__zoom; | |
| var kx = Math.max(kx0, Math.min(kx1, t.kx * (1 + rx * (-1 + Math.pow(2, -d3Selection.event.deltaY * (d3Selection.event.deltaMode ? 120 : 1) / 500))))); | |
| var ky = Math.max(ky0, Math.min(ky1, t.ky * (1 + ry * (-1 + Math.pow(2, -d3Selection.event.deltaY * (d3Selection.event.deltaMode ? 120 : 1) / 500))))); | |
| var p = d3Selection.mouse(this); | |
| // If a scale factor has reached scale extend, sync its value with the other one | |
| if (t.kx === kx0) { | |
| kx = ky >= kx0 ? kx : kx0; | |
| } | |
| if (t.kx === kx1) { | |
| kx = ky <= kx1 ? kx : kx1; | |
| } | |
| if (t.ky === ky0) { | |
| ky = kx >= ky0 ? ky : ky0; | |
| } | |
| if (t.ky === ky1) { | |
| ky = kx <= ky1 ? ky : ky1; | |
| } | |
| // If the mouse is in the same location as before, reuse it. | |
| // If there were recent wheel events, reset the wheel idle timeout. | |
| if (g.wheel) { | |
| if (g.mouse[0][0] !== p[0] || g.mouse[0][1] !== p[1]) { | |
| g.mouse[1] = t.invert(g.mouse[0] = p); | |
| } | |
| clearTimeout(g.wheel); | |
| } | |
| // If this wheel event won’t trigger a transform change, ignore it. | |
| else if (t.kx === ky && t.ky === kx) return; | |
| // Otherwise, capture the mouse point and location at the start. | |
| else { | |
| g.mouse = [p, t.invert(p)]; | |
| d3Transition.interrupt(this); | |
| g.start(); | |
| } | |
| noevent(); | |
| g.wheel = setTimeout(wheelidled, wheelDelay); | |
| g.zoom("mouse", constrain(translate(scale(t, kx, ky), g.mouse[0], g.mouse[1]), g.extent)); | |
| function wheelidled() { | |
| g.wheel = null; | |
| g.end(); | |
| } | |
| } | |
| function mousedowned() { | |
| if (touchending || !filter.apply(this, arguments)) return; | |
| var g = gesture(this, arguments), | |
| v = d3Selection.select(d3Selection.event.view).on("mousemove.zoom", mousemoved, true).on("mouseup.zoom", mouseupped, true), | |
| p = d3Selection.mouse(this); | |
| d3Drag.dragDisable(d3Selection.event.view); | |
| nopropagation(); | |
| g.mouse = [p, this.__zoom.invert(p)]; | |
| d3Transition.interrupt(this); | |
| g.start(); | |
| function mousemoved() { | |
| noevent(); | |
| g.moved = true; | |
| g.zoom("mouse", constrain(translate(g.that.__zoom, g.mouse[0] = d3Selection.mouse(g.that), g.mouse[1]), g.extent)); | |
| } | |
| function mouseupped() { | |
| v.on("mousemove.zoom mouseup.zoom", null); | |
| d3Drag.dragEnable(d3Selection.event.view, g.moved); | |
| noevent(); | |
| g.end(); | |
| } | |
| } | |
| function dblclicked() { | |
| if (!filter.apply(this, arguments)) return; | |
| var t0 = this.__zoom, | |
| p0 = d3Selection.mouse(this), | |
| p1 = t0.invert(p0), | |
| kx1 = t0.kx * (1 + rx * (-1 + (d3Selection.event.shiftKey ? 0.5 : 2))), | |
| ky1 = t0.ky * (1 + ry * (-1 + (d3Selection.event.shiftKey ? 0.5 : 2))), | |
| t1 = constrain(translate(scale(t0, kx1, ky1), p0, p1), extent.apply(this, arguments)); | |
| noevent(); | |
| if (duration > 0) d3Selection.select(this).transition().duration(duration).call(schedule, t1, p0); | |
| else d3Selection.select(this).call(zoom.transform, t1); | |
| } | |
| function touchstarted() { | |
| if (!filter.apply(this, arguments)) return; | |
| var g = gesture(this, arguments), | |
| touches = d3Selection.event.changedTouches, | |
| n = touches.length, i, t, p; | |
| nopropagation(); | |
| for (i = 0; i < n; ++i) { | |
| t = touches[i], p = d3Selection.touch(this, touches, t.identifier); | |
| p = [p, this.__zoom.invert(p), t.identifier]; | |
| if (!g.touch0) g.touch0 = p; | |
| else if (!g.touch1) g.touch1 = p; | |
| } | |
| // If this is a dbltap, reroute to the (optional) dblclick.zoom handler. | |
| if (touchstarting) { | |
| touchstarting = clearTimeout(touchstarting); | |
| if (!g.touch1) { | |
| g.end(); | |
| p = d3Selection.select(this).on("dblclick.zoom"); | |
| if (p) p.apply(this, arguments); | |
| return; | |
| } | |
| } | |
| if (d3Selection.event.touches.length === n) { | |
| touchstarting = setTimeout(function() { touchstarting = null; }, touchDelay); | |
| d3Transition.interrupt(this); | |
| g.start(); | |
| } | |
| } | |
| function touchmoved() { | |
| var g = gesture(this, arguments), | |
| touches = d3Selection.event.changedTouches, | |
| n = touches.length, i, t, p, l; | |
| noevent(); | |
| if (touchstarting) touchstarting = clearTimeout(touchstarting); | |
| for (i = 0; i < n; ++i) { | |
| t = touches[i], p = d3Selection.touch(this, touches, t.identifier); | |
| if (g.touch0 && g.touch0[2] === t.identifier) g.touch0[0] = p; | |
| else if (g.touch1 && g.touch1[2] === t.identifier) g.touch1[0] = p; | |
| } | |
| t = g.that.__zoom; | |
| if (g.touch1) { | |
| var p0 = g.touch0[0], l0 = g.touch0[1], | |
| p1 = g.touch1[0], l1 = g.touch1[1], | |
| dp = (dp = p1[0] - p0[0]) * dp + (dp = p1[1] - p0[1]) * dp, | |
| dl = (dl = l1[0] - l0[0]) * dl + (dl = l1[1] - l0[1]) * dl; | |
| t = scale(t, Math.sqrt(dp / dl), Math.sqrt(dp / dl)); | |
| p = [(p0[0] + p1[0]) / 2, (p0[1] + p1[1]) / 2]; | |
| l = [(l0[0] + l1[0]) / 2, (l0[1] + l1[1]) / 2]; | |
| } | |
| else if (g.touch0) p = g.touch0[0], l = g.touch0[1]; | |
| else return; | |
| g.zoom("touch", constrain(translate(t, p, l), g.extent)); | |
| } | |
| function touchended() { | |
| var g = gesture(this, arguments), | |
| touches = d3Selection.event.changedTouches, | |
| n = touches.length, i, t; | |
| nopropagation(); | |
| if (touchending) clearTimeout(touchending); | |
| touchending = setTimeout(function() { touchending = null; }, touchDelay); | |
| for (i = 0; i < n; ++i) { | |
| t = touches[i]; | |
| if (g.touch0 && g.touch0[2] === t.identifier) delete g.touch0; | |
| else if (g.touch1 && g.touch1[2] === t.identifier) delete g.touch1; | |
| } | |
| if (g.touch1 && !g.touch0) g.touch0 = g.touch1, delete g.touch1; | |
| if (!g.touch0) g.end(); | |
| } | |
| function constrainScaleExtent() { | |
| kx0 = x1 !== x0 ? Math.max(kx0, (extent()[1][0] - extent()[0][0]) / (x1 - x0)) : Infinity; | |
| ky0 = y1 !== y0 ? Math.max(ky0, (extent()[1][1] - extent()[0][1]) / (y1 - y0)) : Infinity; | |
| } | |
| zoom.filter = function(_) { | |
| return arguments.length ? (filter = typeof _ === "function" ? _ : constant(!!_), zoom) : filter; | |
| }; | |
| zoom.extent = function(_) { | |
| return arguments.length ? (extent = typeof _ === "function" ? _ : constant([[+_[0][0], +_[0][1]], [+_[1][0], +_[1][1]]]), constrainScaleExtent(), zoom) : extent; | |
| }; | |
| zoom.scaleExtent = function(_) { | |
| if (arguments.length) { | |
| if (Array.isArray(_[0])) { | |
| kx0 = +_[0][0]; | |
| kx1 = +_[0][1]; | |
| ky0 = +_[1][0]; | |
| ky1 = +_[1][1]; | |
| } else { | |
| kx0 = +_[0]; | |
| kx1 = +_[1]; | |
| ky0 = kx0; | |
| ky1 = kx1; | |
| } | |
| constrainScaleExtent(); | |
| return zoom; | |
| } | |
| return [[kx0, kx1], [ky0, ky1]]; | |
| }; | |
| zoom.scaleRatio = function(_) { | |
| return arguments.length ? (rx = +_[0], ry = +_[1], zoom) : [rx, ry]; | |
| }; | |
| zoom.translateExtent = function(_) { | |
| return arguments.length ? (x0 = +_[0][0], x1 = +_[1][0], y0 = +_[0][1], y1 = +_[1][1], constrainScaleExtent(), zoom) : [[x0, y0], [x1, y1]]; | |
| }; | |
| zoom.duration = function(_) { | |
| return arguments.length ? (duration = +_, zoom) : duration; | |
| }; | |
| zoom.interpolate = function(_) { | |
| return arguments.length ? (interpolate = _, zoom) : interpolate; | |
| }; | |
| zoom.on = function() { | |
| var value = listeners.on.apply(listeners, arguments); | |
| return value === listeners ? zoom : value; | |
| }; | |
| return zoom; | |
| } | |
| exports.xyzoom = zoom; | |
| exports.xyzoomTransform = transform; | |
| exports.xyzoomIdentity = identity; | |
| Object.defineProperty(exports, '__esModule', { value: true }); | |
| })); |
| <!DOCTYPE html> | |
| <!--suppress ALL --> | |
| <html lang="en"> | |
| <head> | |
| <meta charset="UTF-8"> | |
| <title>Title</title> | |
| <script src="https://d3js.org/d3.v4.min.js"></script> | |
| <script src="d3-xyzoom.js"></script> | |
| <style> | |
| .axis path { | |
| display: none; | |
| } | |
| .axis line { | |
| stroke-opacity: 0.1; | |
| shape-rendering: crispEdges; | |
| } | |
| </style> | |
| </head> | |
| <body> | |
| <div><button>Reset</button></div> | |
| <svg width="960" height="500"> | |
| </svg> | |
| <script> | |
| var svg = d3.select('svg'); | |
| var width = +svg.attr('width'); | |
| var height = +svg.attr('height'); | |
| var x = d3.scaleLinear() | |
| .domain([0, 100]) | |
| .range([-1, width + 1]); | |
| var y = d3.scaleLinear() | |
| .domain([0, 100]) | |
| .range([-1, height + 1]); | |
| var ymax = 500; | |
| var zoom = d3.xyzoom() | |
| .extent([[x.range()[0], y.range()[0]], [x.range()[1], y.range()[1]]]) | |
| .scaleExtent([[1, 10], [0, 15]]) | |
| .scaleRatio([0.5, 1]) | |
| .translateExtent([[x.range()[0], y.range()[0]], [x.range()[1], y(ymax)]]) | |
| .on('zoom', zoomed); | |
| var xAxis = d3.axisBottom(x) | |
| .ticks((width + 2) / (height + 2) * 10) | |
| .tickSize(height) | |
| .tickPadding(8 - height); | |
| var yAxis = d3.axisRight(y) | |
| .ticks(10) | |
| .tickSize(width) | |
| .tickPadding(8 - width); | |
| var gX = svg.append('g') | |
| .attr('class', 'axis axis--x') | |
| .call(xAxis); | |
| var gY = svg.append('g') | |
| .attr('class', 'axis axis--y') | |
| .call(yAxis); | |
| d3.select('button') | |
| .on('click', reset); | |
| svg.call(zoom); | |
| function zoomed() { | |
| gX.call(xAxis.scale(d3.event.transform.rescaleX(x))); | |
| gY.call(yAxis.scale(d3.event.transform.rescaleY(y))); | |
| } | |
| function reset() { | |
| svg.transition() | |
| .duration(750) | |
| .call(zoom.transform, d3.xyzoomIdentity); | |
| } | |
| </script> | |
| </body> | |
| </html> |