summaryrefslogtreecommitdiff
path: root/src/static/js/farbtastic.js
diff options
context:
space:
mode:
Diffstat (limited to 'src/static/js/farbtastic.js')
-rw-r--r--src/static/js/farbtastic.js524
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);