hexa isogrid is has now equilateral triangles #35 (8d704eda) · Commits · blackheaven / tinygraphs

draw/isogrids/hexa.go

+16 −11

Original line number	Diff line number	Diff line
		@@ -2,6 +2,7 @@ package isogrids

		import (
		"image/color"
		"math"
		"net/http"

		"github.com/ajstarks/svgo"
		@@ -14,7 +15,11 @@ func Hexa(w http.ResponseWriter, key string, colors []color.RGBA, size, lines in
		canvas.Start(size, size)

		fringeSize := size / lines

		// distance of center of vector to third point of equilateral triangles
		// ABC triangle, O is the center of AB vector
		// OC = SQRT(AC^2 - AO^2)
		distance := int(math.Ceil(math.Sqrt((float64(fringeSize) * float64(fringeSize)) - (float64(fringeSize)/float64(2))*(float64(fringeSize)/float64(2)))))
		fringeSize = distance
		for xL := -1; xL < lines/2; xL++ {
		for yL := -1; yL <= lines; yL++ {

		@@ -33,19 +38,19 @@ func Hexa(w http.ResponseWriter, key string, colors []color.RGBA, size, lines in

		var x1, x2, x3, y1, y2, y3 int
		if (xL % 2) == 0 {
		x1 = (xL) * fringeSize
		x2 = (xL + 1) * fringeSize
		x1 = xL * fringeSize
		x2 = xL*fringeSize + distance
		x3 = x1
		y1 = yL * fringeSize
		y2 = y1 + fringeSize/2
		y3 = (yL + 1) * fringeSize
		y3 = yL*fringeSize + distance
		} else {
		x1 = (xL + 1) * fringeSize
		x1 = xL*fringeSize + distance
		x2 = xL * fringeSize
		x3 = x1
		y1 = yL * fringeSize
		y2 = y1 + fringeSize/2
		y3 = (yL + 1) * fringeSize
		y3 = yL*fringeSize + distance
		}
		xs := []int{x1, x2, x3}
		ys := []int{y1, y2, y3}
		@@ -65,19 +70,19 @@ func Hexa(w http.ResponseWriter, key string, colors []color.RGBA, size, lines in

		var x11, x12, x13, y11, y12, y13 int
		if (xL % 2) == 0 {
		x11 = (xL + 1) * fringeSize
		x11 = xL*fringeSize + distance
		x12 = (xL) * fringeSize
		x13 = x11
		y11 = yL*fringeSize + fringeSize/2
		y12 = y11 + fringeSize/2
		y13 = (yL+1)*fringeSize + fringeSize/2
		y13 = yL*fringeSize + (fringeSize / 2) + distance
		} else {
		x11 = (xL) * fringeSize
		x12 = (xL + 1) * fringeSize
		x11 = xL * fringeSize
		x12 = xL*fringeSize + distance
		x13 = x11
		y11 = yL*fringeSize + fringeSize/2
		y12 = y1 + fringeSize
		y13 = (yL+1)*fringeSize + fringeSize/2
		y13 = yL*fringeSize + (fringeSize / 2) + distance
		}
		xs1 := []int{x11, x12, x13}
		ys1 := []int{y11, y12, y13}