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Diffstat (limited to 'src/static/js/farbtastic.js')
-rw-r--r-- | src/static/js/farbtastic.js | 524 |
1 files changed, 524 insertions, 0 deletions
diff --git a/src/static/js/farbtastic.js b/src/static/js/farbtastic.js new file mode 100644 index 00000000..0045703d --- /dev/null +++ b/src/static/js/farbtastic.js @@ -0,0 +1,524 @@ +// Farbtastic 2.0 alpha +(function ($) { + +var __debug = false; +var __factor = 0.5; + +$.fn.farbtastic = function (options) { + $.farbtastic(this, options); + return this; +}; + +$.farbtastic = function (container, options) { + var container = $(container)[0]; + return container.farbtastic || (container.farbtastic = new $._farbtastic(container, options)); +} + +$._farbtastic = function (container, options) { + var fb = this; + + ///////////////////////////////////////////////////// + + /** + * Link to the given element(s) or callback. + */ + fb.linkTo = function (callback) { + // Unbind previous nodes + if (typeof fb.callback == 'object') { + $(fb.callback).unbind('keyup', fb.updateValue); + } + + // Reset color + fb.color = null; + + // Bind callback or elements + if (typeof callback == 'function') { + fb.callback = callback; + } + else if (typeof callback == 'object' || typeof callback == 'string') { + fb.callback = $(callback); + fb.callback.bind('keyup', fb.updateValue); + if (fb.callback[0].value) { + fb.setColor(fb.callback[0].value); + } + } + return this; + } + fb.updateValue = function (event) { + if (this.value && this.value != fb.color) { + fb.setColor(this.value); + } + } + + /** + * Change color with HTML syntax #123456 + */ + fb.setColor = function (color) { + var unpack = fb.unpack(color); + if (fb.color != color && unpack) { + fb.color = color; + fb.rgb = unpack; + fb.hsl = fb.RGBToHSL(fb.rgb); + fb.updateDisplay(); + } + return this; + } + + /** + * Change color with HSL triplet [0..1, 0..1, 0..1] + */ + fb.setHSL = function (hsl) { + fb.hsl = hsl; + + var convertedHSL = [hsl[0]] + convertedHSL[1] = hsl[1]*__factor+((1-__factor)/2); + convertedHSL[2] = hsl[2]*__factor+((1-__factor)/2); + + fb.rgb = fb.HSLToRGB(convertedHSL); + fb.color = fb.pack(fb.rgb); + fb.updateDisplay(); + return this; + } + + ///////////////////////////////////////////////////// + //excanvas-compatible building of canvases + fb._makeCanvas = function(className){ + var c = document.createElement('canvas'); + if (!c.getContext) { // excanvas hack + c = window.G_vmlCanvasManager.initElement(c); + c.getContext(); //this creates the excanvas children + } + $(c).addClass(className); + return c; + } + + /** + * Initialize the color picker widget. + */ + fb.initWidget = function () { + + // Insert markup and size accordingly. + var dim = { + width: options.width, + height: options.width + }; + $(container) + .html( + '<div class="farbtastic" style="position: relative">' + + '<div class="farbtastic-solid"></div>' + + '</div>' + ) + .children('.farbtastic') + .append(fb._makeCanvas('farbtastic-mask')) + .append(fb._makeCanvas('farbtastic-overlay')) + .end() + .find('*').attr(dim).css(dim).end() + .find('div>*').css('position', 'absolute'); + + // Determine layout + fb.radius = (options.width - options.wheelWidth) / 2 - 1; + fb.square = Math.floor((fb.radius - options.wheelWidth / 2) * 0.7) - 1; + fb.mid = Math.floor(options.width / 2); + fb.markerSize = options.wheelWidth * 0.3; + fb.solidFill = $('.farbtastic-solid', container).css({ + width: fb.square * 2 - 1, + height: fb.square * 2 - 1, + left: fb.mid - fb.square, + top: fb.mid - fb.square + }); + + // Set up drawing context. + fb.cnvMask = $('.farbtastic-mask', container); + fb.ctxMask = fb.cnvMask[0].getContext('2d'); + fb.cnvOverlay = $('.farbtastic-overlay', container); + fb.ctxOverlay = fb.cnvOverlay[0].getContext('2d'); + fb.ctxMask.translate(fb.mid, fb.mid); + fb.ctxOverlay.translate(fb.mid, fb.mid); + + // Draw widget base layers. + fb.drawCircle(); + fb.drawMask(); + } + + /** + * Draw the color wheel. + */ + fb.drawCircle = function () { + var tm = +(new Date()); + // Draw a hue circle with a bunch of gradient-stroked beziers. + // Have to use beziers, as gradient-stroked arcs don't work. + var n = 24, + r = fb.radius, + w = options.wheelWidth, + nudge = 8 / r / n * Math.PI, // Fudge factor for seams. + m = fb.ctxMask, + angle1 = 0, color1, d1; + m.save(); + m.lineWidth = w / r; + m.scale(r, r); + // Each segment goes from angle1 to angle2. + for (var i = 0; i <= n; ++i) { + var d2 = i / n, + angle2 = d2 * Math.PI * 2, + // Endpoints + x1 = Math.sin(angle1), y1 = -Math.cos(angle1); + x2 = Math.sin(angle2), y2 = -Math.cos(angle2), + // Midpoint chosen so that the endpoints are tangent to the circle. + am = (angle1 + angle2) / 2, + tan = 1 / Math.cos((angle2 - angle1) / 2), + xm = Math.sin(am) * tan, ym = -Math.cos(am) * tan, + // New color + color2 = fb.pack(fb.HSLToRGB([d2, 1, 0.5])); + if (i > 0) { + if ($.browser.msie) { + // IE's gradient calculations mess up the colors. Correct along the diagonals. + var corr = (1 + Math.min(Math.abs(Math.tan(angle1)), Math.abs(Math.tan(Math.PI / 2 - angle1)))) / n; + color1 = fb.pack(fb.HSLToRGB([d1 - 0.15 * corr, 1, 0.5])); + color2 = fb.pack(fb.HSLToRGB([d2 + 0.15 * corr, 1, 0.5])); + // Create gradient fill between the endpoints. + var grad = m.createLinearGradient(x1, y1, x2, y2); + grad.addColorStop(0, color1); + grad.addColorStop(1, color2); + m.fillStyle = grad; + // Draw quadratic curve segment as a fill. + var r1 = (r + w / 2) / r, r2 = (r - w / 2) / r; // inner/outer radius. + m.beginPath(); + m.moveTo(x1 * r1, y1 * r1); + m.quadraticCurveTo(xm * r1, ym * r1, x2 * r1, y2 * r1); + m.lineTo(x2 * r2, y2 * r2); + m.quadraticCurveTo(xm * r2, ym * r2, x1 * r2, y1 * r2); + m.fill(); + } + else { + // Create gradient fill between the endpoints. + var grad = m.createLinearGradient(x1, y1, x2, y2); + grad.addColorStop(0, color1); + grad.addColorStop(1, color2); + m.strokeStyle = grad; + // Draw quadratic curve segment. + m.beginPath(); + m.moveTo(x1, y1); + m.quadraticCurveTo(xm, ym, x2, y2); + m.stroke(); + } + } + // Prevent seams where curves join. + angle1 = angle2 - nudge; color1 = color2; d1 = d2; + } + m.restore(); + __debug && $('body').append('<div>drawCircle '+ (+(new Date()) - tm) +'ms'); + }; + + /** + * Draw the saturation/luminance mask. + */ + fb.drawMask = function () { + var tm = +(new Date()); + + // Iterate over sat/lum space and calculate appropriate mask pixel values. + var size = fb.square * 2, sq = fb.square; + function calculateMask(sizex, sizey, outputPixel) { + var isx = 1 / sizex, isy = 1 / sizey; + for (var y = 0; y <= sizey; ++y) { + var l = 1 - y * isy; + for (var x = 0; x <= sizex; ++x) { + var s = 1 - x * isx; + // From sat/lum to alpha and color (grayscale) + var a = 1 - 2 * Math.min(l * s, (1 - l) * s); + var c = (a > 0) ? ((2 * l - 1 + a) * .5 / a) : 0; + + a = a*__factor+(1-__factor)/2; + c = c*__factor+(1-__factor)/2; + + outputPixel(x, y, c, a); + } + } + } + + // Method #1: direct pixel access (new Canvas). + if (fb.ctxMask.getImageData) { + // Create half-resolution buffer. + var sz = Math.floor(size / 2); + var buffer = document.createElement('canvas'); + buffer.width = buffer.height = sz + 1; + var ctx = buffer.getContext('2d'); + var frame = ctx.getImageData(0, 0, sz + 1, sz + 1); + + var i = 0; + calculateMask(sz, sz, function (x, y, c, a) { + frame.data[i++] = frame.data[i++] = frame.data[i++] = c * 255; + frame.data[i++] = a * 255; + }); + + ctx.putImageData(frame, 0, 0); + fb.ctxMask.drawImage(buffer, 0, 0, sz + 1, sz + 1, -sq, -sq, sq * 2, sq * 2); + } + // Method #2: drawing commands (old Canvas). + else if (!$.browser.msie) { + // Render directly at half-resolution + var sz = Math.floor(size / 2); + calculateMask(sz, sz, function (x, y, c, a) { + c = Math.round(c * 255); + fb.ctxMask.fillStyle = 'rgba(' + c + ', ' + c + ', ' + c + ', ' + a +')'; + fb.ctxMask.fillRect(x * 2 - sq - 1, y * 2 - sq - 1, 2, 2); + }); + } + // Method #3: vertical DXImageTransform gradient strips (IE). + else { + var cache_last, cache, w = 6; // Each strip is 6 pixels wide. + var sizex = Math.floor(size / w); + // 6 vertical pieces of gradient per strip. + calculateMask(sizex, 6, function (x, y, c, a) { + if (x == 0) { + cache_last = cache; + cache = []; + } + c = Math.round(c * 255); + a = Math.round(a * 255); + // We can only start outputting gradients once we have two rows of pixels. + if (y > 0) { + var c_last = cache_last[x][0], + a_last = cache_last[x][1], + color1 = fb.packDX(c_last, a_last), + color2 = fb.packDX(c, a), + y1 = Math.round(fb.mid + ((y - 1) * .333 - 1) * sq), + y2 = Math.round(fb.mid + (y * .333 - 1) * sq); + $('<div>').css({ + position: 'absolute', + filter: "progid:DXImageTransform.Microsoft.Gradient(StartColorStr="+ color1 +", EndColorStr="+ color2 +", GradientType=0)", + top: y1, + height: y2 - y1, + // Avoid right-edge sticking out. + left: fb.mid + (x * w - sq - 1), + width: w - (x == sizex ? Math.round(w / 2) : 0) + }).appendTo(fb.cnvMask); + } + cache.push([c, a]); + }); + } + __debug && $('body').append('<div>drawMask '+ (+(new Date()) - tm) +'ms'); + } + + /** + * Draw the selection markers. + */ + fb.drawMarkers = function () { + // Determine marker dimensions + var sz = options.width, lw = Math.ceil(fb.markerSize / 4), r = fb.markerSize - lw + 1; + var angle = fb.hsl[0] * 6.28, + x1 = Math.sin(angle) * fb.radius, + y1 = -Math.cos(angle) * fb.radius, + x2 = 2 * fb.square * (.5 - fb.hsl[1]), + y2 = 2 * fb.square * (.5 - fb.hsl[2]), + c1 = fb.invert ? '#fff' : '#000', + c2 = fb.invert ? '#000' : '#fff'; + var circles = [ + { x: x1, y: y1, r: r, c: '#000', lw: lw + 1 }, + { x: x1, y: y1, r: fb.markerSize, c: '#fff', lw: lw }, + { x: x2, y: y2, r: r, c: c2, lw: lw + 1 }, + { x: x2, y: y2, r: fb.markerSize, c: c1, lw: lw }, + ]; + + // Update the overlay canvas. + fb.ctxOverlay.clearRect(-fb.mid, -fb.mid, sz, sz); + for (i in circles) { + var c = circles[i]; + fb.ctxOverlay.lineWidth = c.lw; + fb.ctxOverlay.strokeStyle = c.c; + fb.ctxOverlay.beginPath(); + fb.ctxOverlay.arc(c.x, c.y, c.r, 0, Math.PI * 2, true); + fb.ctxOverlay.stroke(); + } + } + + /** + * Update the markers and styles + */ + fb.updateDisplay = function () { + // Determine whether labels/markers should invert. + fb.invert = (fb.rgb[0] * 0.3 + fb.rgb[1] * .59 + fb.rgb[2] * .11) <= 0.6; + + // Update the solid background fill. + fb.solidFill.css('backgroundColor', fb.pack(fb.HSLToRGB([fb.hsl[0], 1, 0.5]))); + + // Draw markers + fb.drawMarkers(); + + // Linked elements or callback + if (typeof fb.callback == 'object') { + // Set background/foreground color + $(fb.callback).css({ + backgroundColor: fb.color, + color: fb.invert ? '#fff' : '#000' + }); + + // Change linked value + $(fb.callback).each(function() { + if ((typeof this.value == 'string') && this.value != fb.color) { + this.value = fb.color; + } + }); + } + else if (typeof fb.callback == 'function') { + fb.callback.call(fb, fb.color); + } + } + + /** + * Helper for returning coordinates relative to the center. + */ + fb.widgetCoords = function (event) { + return { + x: event.pageX - fb.offset.left - fb.mid, + y: event.pageY - fb.offset.top - fb.mid + }; + } + + /** + * Mousedown handler + */ + fb.mousedown = function (event) { + // Capture mouse + if (!$._farbtastic.dragging) { + $(document).bind('mousemove', fb.mousemove).bind('mouseup', fb.mouseup); + $._farbtastic.dragging = true; + } + + // Update the stored offset for the widget. + fb.offset = $(container).offset(); + + // Check which area is being dragged + var pos = fb.widgetCoords(event); + fb.circleDrag = Math.max(Math.abs(pos.x), Math.abs(pos.y)) > (fb.square + 2); + + // Process + fb.mousemove(event); + return false; + } + + /** + * Mousemove handler + */ + fb.mousemove = function (event) { + // Get coordinates relative to color picker center + var pos = fb.widgetCoords(event); + + // Set new HSL parameters + if (fb.circleDrag) { + var hue = Math.atan2(pos.x, -pos.y) / 6.28; + fb.setHSL([(hue + 1) % 1, fb.hsl[1], fb.hsl[2]]); + } + else { + var sat = Math.max(0, Math.min(1, -(pos.x / fb.square / 2) + .5)); + var lum = Math.max(0, Math.min(1, -(pos.y / fb.square / 2) + .5)); + fb.setHSL([fb.hsl[0], sat, lum]); + } + return false; + } + + /** + * Mouseup handler + */ + fb.mouseup = function () { + // Uncapture mouse + $(document).unbind('mousemove', fb.mousemove); + $(document).unbind('mouseup', fb.mouseup); + $._farbtastic.dragging = false; + } + + /* Various color utility functions */ + fb.dec2hex = function (x) { + return (x < 16 ? '0' : '') + x.toString(16); + } + + fb.packDX = function (c, a) { + return '#' + fb.dec2hex(a) + fb.dec2hex(c) + fb.dec2hex(c) + fb.dec2hex(c); + }; + + fb.pack = function (rgb) { + var r = Math.round(rgb[0] * 255); + var g = Math.round(rgb[1] * 255); + var b = Math.round(rgb[2] * 255); + return '#' + fb.dec2hex(r) + fb.dec2hex(g) + fb.dec2hex(b); + }; + + fb.unpack = function (color) { + if (color.length == 7) { + function x(i) { + return parseInt(color.substring(i, i + 2), 16) / 255; + } + return [ x(1), x(3), x(5) ]; + } + else if (color.length == 4) { + function x(i) { + return parseInt(color.substring(i, i + 1), 16) / 15; + } + return [ x(1), x(2), x(3) ]; + } + }; + + fb.HSLToRGB = function (hsl) { + var m1, m2, r, g, b; + var h = hsl[0], s = hsl[1], l = hsl[2]; + m2 = (l <= 0.5) ? l * (s + 1) : l + s - l * s; + m1 = l * 2 - m2; + return [ + this.hueToRGB(m1, m2, h + 0.33333), + this.hueToRGB(m1, m2, h), + this.hueToRGB(m1, m2, h - 0.33333) + ]; + }; + + fb.hueToRGB = function (m1, m2, h) { + h = (h + 1) % 1; + if (h * 6 < 1) return m1 + (m2 - m1) * h * 6; + if (h * 2 < 1) return m2; + if (h * 3 < 2) return m1 + (m2 - m1) * (0.66666 - h) * 6; + return m1; + }; + + fb.RGBToHSL = function (rgb) { + var r = rgb[0], g = rgb[1], b = rgb[2], + min = Math.min(r, g, b), + max = Math.max(r, g, b), + delta = max - min, + h = 0, + s = 0, + l = (min + max) / 2; + if (l > 0 && l < 1) { + s = delta / (l < 0.5 ? (2 * l) : (2 - 2 * l)); + } + if (delta > 0) { + if (max == r && max != g) h += (g - b) / delta; + if (max == g && max != b) h += (2 + (b - r) / delta); + if (max == b && max != r) h += (4 + (r - g) / delta); + h /= 6; + } + return [h, s, l]; + }; + + // Parse options. + if (!options.callback) { + options = { callback: options }; + } + options = $.extend({ + width: 300, + wheelWidth: (options.width || 300) / 10, + callback: null + }, options); + + // Initialize. + fb.initWidget(); + + // Install mousedown handler (the others are set on the document on-demand) + $('canvas.farbtastic-overlay', container).mousedown(fb.mousedown); + + // Set linked elements/callback + if (options.callback) { + fb.linkTo(options.callback); + } + // Set to gray. + fb.setColor('#808080'); +} + +})(jQuery); |