added option halfPie to pie type chart

examples/js/Examples.js

@@ -72,6 +72,7 @@ Examples.prototype = {
         "basic-bar-stacked",
         "basic-stacked-horizontal",
         "basic-pie",
+        "half-pie",
         "basic-radar",
         "basic-bubble",
         "basic-candle",

examples/js/examples/half-pie.js

@@ -0,0 +1,47 @@
+(function () {
+
+Flotr.ExampleList.add({
+  key : 'half-pie',
+  name : 'Half Pie',
+  callback : half_pie
+});
+
+function half_pie (container) {
+
+  var
+    d1 = [[0, 4]],
+    d2 = [[0, 3]],
+    d3 = [[0, 1.03]],
+    d4 = [[0, 3.5]],
+    graph;
+
+  graph = Flotr.draw(container, [
+    { data : d1, label : 'Republican' },
+    { data : d2, label : 'Democratic' },
+    { data : d3, label : 'Green'},
+    { data : d4, label : 'Pirates' }
+  ], {
+    HtmlText : true,
+    grid : {
+      verticalLines : false,
+      horizontalLines : false
+    },
+    xaxis : { showLabels : false },
+    yaxis : { showLabels : false },
+    pie : {
+      show : true, 
+      explode : 6,
+      startAngle: 0.5,
+      labelFormatter: function(){
+      },
+      halfPie: true
+    },
+    mouse : { track : true },
+    legend : {
+      position : 'se',
+      backgroundColor : '#D2E8FF'
+    }
+  });
+}
+
+})();

examples/js/includes.dev.js

@@ -60,6 +60,7 @@ yepnope([
   'js/examples/basic-bars.js',
   'js/examples/basic-bars-stacked.js',
   'js/examples/basic-pie.js',
+  'js/examples/half-pie.js',
   'js/examples/basic-radar.js',
   'js/examples/basic-bubble.js',
   'js/examples/basic-candle.js',

js/types/pie.js

@@ -28,7 +28,8 @@ Flotr.addType('pie', {
     pie3D: false,          // => whether to draw the pie in 3 dimenstions or not (ineffective) 
     pie3DviewAngle: (Math.PI/2 * 0.8),
     pie3DspliceThickness: 20,
-    epsilon: 0.1           // => how close do you have to get to hit empty slice
+    epsilon: 0.1,          // => how close do you have to get to hit empty slice
+    halfPie: false
   },
 
   draw : function (options) {
@@ -42,17 +43,18 @@ Flotr.addType('pie', {
       lineWidth     = options.lineWidth,
       shadowSize    = options.shadowSize,
       sizeRatio     = options.sizeRatio,
-      height        = options.height,
-      width         = options.width,
+      circleRatio   = options.halfPie ? 1 : 2,
+      height        = options.height ,
+      width         = options.width ,
       explode       = options.explode,
       color         = options.color,
       fill          = options.fill,
       fillStyle     = options.fillStyle,
-      radius        = Math.min(canvas.width, canvas.height) * sizeRatio / 2,
+      radius        = Math.min(canvas.width, canvas.height) * sizeRatio /circleRatio,
       value         = data[0][1],
       html          = [],
       vScale        = 1,//Math.cos(series.pie.viewAngle);
-      measure       = Math.PI * 2 * value / this.total,
+      measure       = Math.PI * circleRatio * value / this.total,
       startAngle    = this.startAngle || (2 * Math.PI * options.startAngle), // TODO: this initial startAngle is already in radians (fixing will be test-unstable)
       endAngle      = startAngle + measure,
       bisection     = startAngle + measure / 2,
@@ -67,7 +69,7 @@ Flotr.addType('pie', {
       x, y;
 
     context.save();
-    context.translate(width / 2, height / 2);
+    context.translate(width / 2, height / circleRatio);
     context.scale(1, vScale);
 
     x = Math.cos(bisection) * explode;
@@ -146,11 +148,12 @@ Flotr.addType('pie', {
       mouse     = args[0],
       n         = args[1],
       slice     = this.slices[index],
-      x         = mouse.relX - options.width / 2,
-      y         = mouse.relY - options.height / 2,
+      circleRatio   = options.halfPie ? 1 : 2,
+      x         = mouse.relX - options.width / circleRatio,
+      y         = mouse.relY - options.height/ circleRatio,
       r         = Math.sqrt(x * x + y * y),
       theta     = Math.atan(y / x),
-      circle    = Math.PI * 2,
+      circle    = Math.PI * circleRatio,
       explode   = slice.explode || options.explode,
       start     = slice.start % circle,
       end       = slice.end % circle,
@@ -184,23 +187,25 @@ Flotr.addType('pie', {
   drawHit: function (options) {
     var
       context = options.context,
+      circleRatio   = options.halfPie ? 1 : 2,
       slice = this.slices[options.args.seriesIndex];
 
     context.save();
-    context.translate(options.width / 2, options.height / 2);
+    context.translate(options.width/circleRatio, options.height/circleRatio);
     this.plotSlice(slice.x, slice.y, slice.radius, slice.start, slice.end, context);
     context.stroke();
     context.restore();
   },
   clearHit : function (options) {
     var
       context = options.context,
+      circleRatio   = options.halfPie ? 1 : 2,
       slice = this.slices[options.args.seriesIndex],
       padding = 2 * options.lineWidth,
       radius = slice.radius + padding;
 
     context.save();
-    context.translate(options.width / 2, options.height / 2);
+    context.translate(options.width/circleRatio, options.height/circleRatio);
     context.clearRect(
       slice.x - radius,
       slice.y - radius,