stuff.

_examples/overlap/main.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"net/http"
+
+	chart "github.com/wcharczuk/go-chart"
+	"github.com/wcharczuk/go-chart/drawing"
+)
+
+func conditionalColor(condition bool, trueColor drawing.Color, falseColor drawing.Color) drawing.Color {
+	if condition {
+		return trueColor
+	}
+	return falseColor
+}
+
+func drawChart(res http.ResponseWriter, req *http.Request) {
+	r, _ := chart.PNG(1024, 1024)
+
+	b0 := chart.Box{Left: 100, Top: 100, Right: 400, Bottom: 200}
+	b1 := chart.Box{Left: 500, Top: 100, Right: 900, Bottom: 200}
+	b0r := b0.Corners().Rotate(45).Shift(0, 200)
+
+	chart.Draw.Box(r, b0, chart.Style{
+		StrokeColor: drawing.ColorRed,
+		StrokeWidth: 2,
+		FillColor:   conditionalColor(b0.Corners().Overlaps(b1.Corners()), drawing.ColorRed, drawing.ColorTransparent),
+	})
+
+	chart.Draw.Box(r, b1, chart.Style{
+		StrokeColor: drawing.ColorBlue,
+		StrokeWidth: 2,
+		FillColor:   conditionalColor(b1.Corners().Overlaps(b0.Corners()), drawing.ColorRed, drawing.ColorTransparent),
+	})
+
+	chart.Draw.Box2d(r, b0r, chart.Style{
+		StrokeColor: drawing.ColorGreen,
+		StrokeWidth: 2,
+		FillColor:   conditionalColor(b0r.Overlaps(b0.Corners()), drawing.ColorRed, drawing.ColorTransparent),
+	})
+
+	res.Header().Set("Content-Type", "image/png")
+	r.Save(res)
+}
+
+func main() {
+	http.HandleFunc("/", drawChart)
+	http.ListenAndServe(":8080", nil)
+}