Method ClosestDataToPixel

plot/plot.go:222–243

ClosestDataToPixel returns the Plotter data point closest to given pixel point, in the Pixels image.

(px, py int)

// ClosestDataToPixel returns the Plotter data point closest to given pixel point,
// in the Pixels image.
func (pt *Plot) ClosestDataToPixel(px, py int) (plt Plotter, idx int, dist float32, data, pixel math32.Vector2, legend string) {
	tp := math32.Vec2(float32(px), float32(py))
	dist = float32(math32.MaxFloat32)
	for _, p := range pt.Plotters {
		dts, pxls := p.XYData()
		for i := range pxls.Len() {
			ptx, pty := pxls.XY(i)
			pxy := math32.Vec2(ptx, pty)
			d := pxy.DistanceTo(tp)
			if d < dist {
				dist = d
				pixel = pxy
				plt = p
				idx = i
				dx, dy := dts.XY(i)
				data = math32.Vec2(dx, dy)
				legend = pt.Legend.LegendForPlotter(p)
			}
		}
	}
	return
}