    /**
     * @private
     */
    Ext.define('Ext.chart.axis.Radial', {

        /* Begin Definitions */

        extend: 'Ext.chart.axis.Abstract',

        /* End Definitions */

        position: 'radial',

        alias: 'axis.radial',

        drawAxis: function(init) {
            var chart = this.chart,
                surface = chart.surface,
                bbox = chart.chartBBox,
                store = chart.store,
                l = store.getCount(),
                centerX = bbox.x + (bbox.width / 2),
                centerY = bbox.y + (bbox.height / 2),
                rho = Math.min(bbox.width, bbox.height) /2,
                sprites = [], sprite,
                steps = this.steps,
                i, j, pi2 = Math.PI * 2,
                cos = Math.cos, sin = Math.sin;

            if (this.sprites && !chart.resizing) {
                this.drawLabel();
                return;
            }

            if (!this.sprites) {
                //draw circles
                for (i = 1; i <= steps; i++) {
                    sprite = surface.add({
                        type: 'circle',
                        x: centerX,
                        y: centerY,
                        radius: Math.max(rho * i / steps, 0),
                        stroke: '#ccc'
                    });
                    sprite.setAttributes({
                        hidden: false
                    }, true);
                    sprites.push(sprite);
                }
                //draw lines
                for (i = 0; i < l; i++) {
                    sprite = surface.add({
                        type: 'path',
                        path: ['M', centerX, centerY, 'L', centerX + rho * cos(i / l * pi2), centerY + rho * sin(i / l * pi2), 'Z'],
                        stroke: '#ccc'
                    });
                    sprite.setAttributes({
                        hidden: false
                    }, true);
                    sprites.push(sprite);
                }
            } else {
                sprites = this.sprites;
                //draw circles
                for (i = 0; i < steps; i++) {
                    sprites[i].setAttributes({
                        x: centerX,
                        y: centerY,
                        radius: Math.max(rho * (i + 1) / steps, 0),
                        stroke: '#ccc'
                    }, true);
                }
                //draw lines
                for (j = 0; j < l; j++) {
                    sprites[i + j].setAttributes({
                        path: ['M', centerX, centerY, 'L', centerX + rho * cos(j / l * pi2), centerY + rho * sin(j / l * pi2), 'Z'],
                        stroke: '#ccc'
                    }, true);
                }
            }
            this.sprites = sprites;

            this.drawLabel();
        },

        drawLabel: function() {
            var chart = this.chart,
                seriesItems = chart.series.items,
                series,
                surface = chart.surface,
                bbox = chart.chartBBox,
                store = chart.store,
                data = store.data.items,
                ln, record,
                centerX = bbox.x + (bbox.width / 2),
                centerY = bbox.y + (bbox.height / 2),
                rho = Math.min(bbox.width, bbox.height) /2,
                max = Math.max, round = Math.round,
                labelArray = [], label,
                fields = [], nfields,
                categories = [], xField,
                aggregate = !this.maximum,
                maxValue = this.maximum || 0,
                steps = this.steps, i = 0, j, dx, dy,
                pi2 = Math.PI * 2,
                cos = Math.cos, sin = Math.sin,
                display = this.label.display,
                draw = display !== 'none',
                margin = 10;

            if (!draw) {
                return;
            }

            //get all rendered fields
            for (i = 0, ln = seriesItems.length; i < ln; i++) {
                series = seriesItems[i];
                fields.push(series.yField);
                xField = series.xField;
            }

            //get maxValue to interpolate
            for (j = 0, ln = data.length; j < ln; j++) {
                record = data[j];
                if (aggregate) {
                    for (i = 0, nfields = fields.length; i < nfields; i++) {
                        maxValue = max(+record.get(fields[i]), maxValue);
                    }
                }
                categories.push(record.get(xField));
            }
            if (!this.labelArray) {
                if (display != 'categories') {
                    //draw scale
                    for (i = 1; i <= steps; i++) {
                        label = surface.add({
                            type: 'text',
                            text: round(i / steps * maxValue),
                            x: centerX,
                            y: centerY - rho * i / steps,
                            'text-anchor': 'middle',
                            'stroke-width': 0.1,
                            stroke: '#333'
                        });
                        label.setAttributes({
                            hidden: false
                        }, true);
                        labelArray.push(label);
                    }
                }
                if (display != 'scale') {
                    //draw text
                    for (j = 0, steps = categories.length; j < steps; j++) {
                        dx = cos(j / steps * pi2) * (rho + margin);
                        dy = sin(j / steps * pi2) * (rho + margin);
                        label = surface.add({
                            type: 'text',
                            text: categories[j],
                            x: centerX + dx,
                            y: centerY + dy,
                            'text-anchor': dx * dx <= 0.001? 'middle' : (dx < 0? 'end' : 'start')
                        });
                        label.setAttributes({
                            hidden: false
                        }, true);
                        labelArray.push(label);
                    }
                }
            }
            else {
                labelArray = this.labelArray;
                if (display != 'categories') {
                    //draw values
                    for (i = 0; i < steps; i++) {
                        labelArray[i].setAttributes({
                            text: round((i + 1) / steps * maxValue),
                            x: centerX,
                            y: centerY - rho * (i + 1) / steps,
                            'text-anchor': 'middle',
                            'stroke-width': 0.1,
                            stroke: '#333'
                        }, true);
                    }
                }
                if (display != 'scale') {
                    //draw text
                    for (j = 0, steps = categories.length; j < steps; j++) {
                        dx = cos(j / steps * pi2) * (rho + margin);
                        dy = sin(j / steps * pi2) * (rho + margin);
                        if (labelArray[i + j]) {
                            labelArray[i + j].setAttributes({
                                type: 'text',
                                text: categories[j],
                                x: centerX + dx,
                                y: centerY + dy,
                                'text-anchor': dx * dx <= 0.001? 'middle' : (dx < 0? 'end' : 'start')
                            }, true);
                        }
                    }
                }
            }
            this.labelArray = labelArray;
        }
    });