init

generator/generator.go

@@ -0,0 +1,68 @@
+package generator
+
+import (
+	"image"
+	"image/color"
+	"image/png"
+	"io"
+
+	"github.com/pkg/errors"
+	"github.com/tribalwarshelp/shared/models"
+)
+
+type Marker struct {
+	Villages []*models.Village
+	Color    string
+}
+
+type Config struct {
+	Markers     []*Marker
+	Destination io.Writer
+	MapSize     int
+}
+
+func Generate(cfg Config) error {
+	upLeft := image.Point{0, 0}
+	lowRight := image.Point{cfg.MapSize, cfg.MapSize}
+
+	img := image.NewRGBA(image.Rectangle{upLeft, lowRight})
+	backgroundColor, err := parseHexColorFast("#69380e")
+	if err != nil {
+		return err
+	}
+
+	// Background.
+	for y := 0; y < cfg.MapSize; y++ {
+		for x := 0; x < cfg.MapSize; x++ {
+			img.Set(x, y, backgroundColor)
+		}
+	}
+
+	// Markers
+	for _, marker := range cfg.Markers {
+		parsedColor, err := parseHexColorFast(marker.Color)
+		if err != nil {
+			return err
+		}
+		for _, village := range marker.Villages {
+			img.Set(village.X, village.Y, parsedColor)
+		}
+	}
+
+	//Continents
+	for y := cfg.MapSize / 10; y < cfg.MapSize; y += cfg.MapSize / 10 {
+		for x := 0; x < cfg.MapSize; x++ {
+			img.Set(x, y, color.Black)
+		}
+	}
+	for x := cfg.MapSize / 10; x < cfg.MapSize; x += cfg.MapSize / 10 {
+		for y := 0; y < cfg.MapSize; y++ {
+			img.Set(x, y, color.Black)
+		}
+	}
+
+	if err := png.Encode(cfg.Destination, img); err != nil {
+		return errors.Wrap(err, "map-generator")
+	}
+	return nil
+}

generator/helpers.go

@@ -0,0 +1,47 @@
+package generator
+
+import (
+	"fmt"
+	"image/color"
+)
+
+var (
+	errInvalidFormat = fmt.Errorf("invalid format")
+)
+
+func parseHexColorFast(s string) (color.RGBA, error) {
+	var err error
+	c := color.RGBA{}
+	c.A = 0xff
+
+	if s[0] != '#' {
+		return c, errInvalidFormat
+	}
+
+	hexToByte := func(b byte) byte {
+		switch {
+		case b >= '0' && b <= '9':
+			return b - '0'
+		case b >= 'a' && b <= 'f':
+			return b - 'a' + 10
+		case b >= 'A' && b <= 'F':
+			return b - 'A' + 10
+		}
+		err = errInvalidFormat
+		return 0
+	}
+
+	switch len(s) {
+	case 7:
+		c.R = hexToByte(s[1])<<4 + hexToByte(s[2])
+		c.G = hexToByte(s[3])<<4 + hexToByte(s[4])
+		c.B = hexToByte(s[5])<<4 + hexToByte(s[6])
+	case 4:
+		c.R = hexToByte(s[1]) * 17
+		c.G = hexToByte(s[2]) * 17
+		c.B = hexToByte(s[3]) * 17
+	default:
+		err = errInvalidFormat
+	}
+	return c, err
+}

go.mod

@@ -0,0 +1,8 @@
+module github.com/tribalwarshelp/map-generator
+
+go 1.14
+
+require (
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/tribalwarshelp/shared v0.0.0-20200622084436-3a768c8bf574 // indirect
+)

go.sum

@@ -0,0 +1,4 @@
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/tribalwarshelp/shared v0.0.0-20200622084436-3a768c8bf574 h1:y2EoH6zRK9Uc0AeswnJRYUUIQYcSLZB5VDFuxPCKxNM=
+github.com/tribalwarshelp/shared v0.0.0-20200622084436-3a768c8bf574/go.mod h1:tf+2yTHasV6jAF3V2deZ9slNoCyBzC0fMdTjI7clf6Y=