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fix for issues/56

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This commit is contained in:
Will Charczuk 2017-10-12 13:29:55 -07:00
parent a0ea012903
commit f72f7fd57b
4 changed files with 43 additions and 1 deletions
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19
_examples/pie_chart/main.go
View File

@ -30,7 +30,26 @@ func drawChart(res http.ResponseWriter, req *http.Request) {
}
}
func drawChartRegression(res http.ResponseWriter, req *http.Request) {
pie := chart.PieChart{
Width: 512,
Height: 512,
Values: []chart.Value{
{Value: 5, Label: "Blue"},
{Value: 2, Label: "Two"},
{Value: 1, Label: "One"},
},
}
res.Header().Set("Content-Type", chart.ContentTypeSVG)
err := pie.Render(chart.SVG, res)
if err != nil {
fmt.Printf("Error rendering pie chart: %v\n", err)
}
}
func main() {
http.HandleFunc("/", drawChart)
http.HandleFunc("/reg", drawChartRegression)
log.Fatal(http.ListenAndServe(":8080", nil))
}

17
_examples/pie_chart/reg.svg Normal file
View File

@ -0,0 +1,17 @@
<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="512" height="512">
<path d="M 256 256
L 507 256
A 251 251 225.00 1 1 79 79
L 256 256
Z" style="stroke-width:5;stroke:rgba(255,255,255,1.0);fill:rgba(106,195,203,1.0)"/>
<path d="M 256 256
L 79 79
A 251 251 90.00 0 1 433 79
L 256 256
Z" style="stroke-width:5;stroke:rgba(255,255,255,1.0);fill:rgba(42,190,137,1.0)"/>
<path d="M 256 256
L 433 79
A 251 251 45.00 0 1 507 256
L 256 256
Z" style="stroke-width:5;stroke:rgba(255,255,255,1.0);fill:rgba(110,128,139,1.0)"/>
</svg>
Side by Side

After

Width:  |  Height:  |  Size: 565 B

1
pie_chart.go
View File

@ -11,6 +11,7 @@ import (
)
const (
_pi = math.Pi
_pi2 = math.Pi / 2.0
_pi4 = math.Pi / 4.0
)

7
vector_renderer.go
View File

@ -107,7 +107,12 @@ func (vr *vectorRenderer) ArcTo(cx, cy int, rx, ry, startAngle, delta float64) {
dd := util.Math.RadiansToDegrees(delta)
vr.p = append(vr.p, fmt.Sprintf("A %d %d %0.2f 0 1 %d %d", int(rx), int(ry), dd, endx, endy))
largeArcFlag := 0
if delta > _pi {
largeArcFlag = 1
}
vr.p = append(vr.p, fmt.Sprintf("A %d %d %0.2f %d 1 %d %d", int(rx), int(ry), dd, largeArcFlag, endx, endy))
}
// Close closes a shape.