Commit 8510b998 authored by santiaago's avatar santiaago
Browse files

fix hexagon error

parent 8db44cd6

draw/isogrids/hexa.go

+16 −10
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ package isogrids 


import (

	"image/color"

	"log"

	"math"

	"net/http"
@@ -15,11 +16,15 @@ func Hexa(w http.ResponseWriter, key string, colors []color.RGBA, size, lines in 
	canvas.Start(size, size)



	fringeSize := size / lines

	log.Println(fringeSize)

	// 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

	lines = size / fringeSize

	offset := size - fringeSize*lines

	log.Println(offset)

	for xL := 0; xL < lines/2; xL++ {

		for yL := 0; yL < lines; yL++ {
@@ -54,35 +59,35 @@ func Hexa(w http.ResponseWriter, key string, colors []color.RGBA, size, lines in 
			}

			xs := []int{x1, x2, x3}

			ys := []int{y1, y2, y3}



			if lines%4 != 0 {

				xs[0] = x2

				xs[1] = x1

				xs[2] = x2

			}



			canvas.Polygon(xs, ys, fill1)



			xs[0] = (lines * fringeSize) - xs[0]

			xs[1] = (lines * fringeSize) - xs[1]

			xs[2] = (lines * fringeSize) - xs[2]

			canvas.Polygon(xs, ys, fill1)

			xsMirror := []int{0, 0, 0}

			xsMirror[0] = (lines * fringeSize) - xs[0]

			xsMirror[1] = (lines * fringeSize) - xs[1]

			xsMirror[2] = (lines * fringeSize) - xs[2]



			canvas.Polygon(xsMirror, ys, fill1)



			var x11, x12, x13, y11, y12, y13 int

			if (xL % 2) == 0 {

				x11 = xL*fringeSize + distance

				x12 = (xL) * fringeSize

				x12 = xL * fringeSize

				x13 = x11

				y11 = yL*fringeSize + fringeSize/2

				y12 = y11 + fringeSize/2

				y13 = yL*fringeSize + (fringeSize / 2) + distance

				y12 = y3 // to have a perfect hexagon, we make sure that previews triangle and this one touch each other in this point

				y13 = yL*fringeSize + fringeSize/2 + distance

			} else {

				x11 = xL * fringeSize

				x12 = xL*fringeSize + distance

				x13 = x11

				y11 = yL*fringeSize + fringeSize/2

				y12 = y1 + fringeSize

				y13 = yL*fringeSize + (fringeSize / 2) + distance

				y13 = yL*fringeSize + fringeSize/2 + distance

			}

			xs1 := []int{x11, x12, x13}

			ys1 := []int{y11, y12, y13}
@@ -96,6 +101,7 @@ func Hexa(w http.ResponseWriter, key string, colors []color.RGBA, size, lines in 
			xs1[0] = (lines * fringeSize) - xs1[0]

			xs1[1] = (lines * fringeSize) - xs1[1]

			xs1[2] = (lines * fringeSize) - xs1[2]



			canvas.Polygon(xs1, ys1, fill2)

		}

	}