Implement fetaure request issue #17

mtseeder and mtwebmapper got an option to set the background color where no nodes are generated, yet.

cmd/mtseeder/baselevel.go

@@ -5,6 +5,7 @@
 package main
 
 import (
+	"image/color"
 	"log"
 	"os"
 	"path/filepath"
@@ -39,7 +40,7 @@ func createBaseLevel(
 	address string,
 	xMin, yMin, zMin, xMax, yMax, zMax int,
 	transparent bool, transparentDim float32,
-	colorsFile, outDir string,
+	colorsFile string, bg color.RGBA, outDir string,
 	numWorkers int) (err error) {
 
 	var colors *common.Colors
@@ -65,7 +66,7 @@ func createBaseLevel(
 		}
 		done.Add(1)
 		btc := common.NewBaseTileCreator(
-			client, colors,
+			client, colors, bg,
 			int16(yMin), int16(yMax),
 			transparent, baseDir, false)
 		go createTiles(btc, jobs, &done)

cmd/mtseeder/main.go

@@ -7,6 +7,7 @@ package main
 import (
 	"flag"
 	"fmt"
+	"image/color"
 	"log"
 
 	"bitbucket.org/s_l_teichmann/mtsatellite/common"
@@ -19,6 +20,7 @@ func main() {
 		xMin, yMin, zMin int
 		xMax, yMax, zMax int
 		colorsFile       string
+		bgColor          string
 		outDir           string
 		numWorkers       int
 		skipBaseLevel    bool
@@ -28,6 +30,8 @@ func main() {
 		version          bool
 	)
 
+	defaultBgColor := common.ColorToHex(common.BackgroundColor)
+
 	flag.IntVar(&port, "port", 6379, "port to of mtredisalize server")
 	flag.IntVar(&port, "p", 6379, "port to of mtredisalize server (shorthand)")
 	flag.StringVar(&host, "host", "localhost", "host to mtredisalize server")
@@ -38,6 +42,8 @@ func main() {
 	flag.IntVar(&zMin, "zmin", -1933, "z min of the area to tile")
 	flag.IntVar(&zMax, "zmax", 1932, "z max of the area to tile")
 	flag.StringVar(&colorsFile, "colors", "colors.txt", "definition of colors")
+	flag.StringVar(&bgColor, "background", defaultBgColor, "background color")
+	flag.StringVar(&bgColor, "bg", defaultBgColor, "background color (shorthand)")
 	flag.StringVar(&outDir, "output-dir", "map", "directory with the resulting image tree")
 	flag.StringVar(&outDir, "o", "map", "directory with the resulting image tree")
 	flag.IntVar(&numWorkers, "workers", 1, "number of workers")
@@ -62,6 +68,13 @@ func main() {
 		common.PrintVersionAndExit()
 	}
 
+	var bg color.RGBA
+	var err error
+	if bg, err = common.ParseColor(bgColor); err != nil {
+		log.Printf("WARN: Cannot parse background color '%s': %s\n", bgColor, err)
+		bg = common.BackgroundColor
+	}
+
 	if !skipBaseLevel {
 		td := common.Clamp32f(float32(transparentDim/100.0), 0.0, 1.0)
 		address := fmt.Sprintf("%s:%d", host, port)
@@ -69,14 +82,15 @@ func main() {
 			address,
 			xMin, yMin, zMin, xMax, yMax, zMax,
 			transparent, td,
-			colorsFile,
+			colorsFile, bg,
 			outDir,
 			numWorkers); err != nil {
 			log.Fatalf("Creating base level tiles failed: %s", err)
 		}
 	}
 	if !skipPyramid {
-		if err := createPyramid(outDir, numWorkers); err != nil {
+		pc := pyramidCreator{numWorkers: numWorkers, outDir: outDir, bg: bg}
+		if err := pc.create(); err != nil {
 			log.Fatalf("Creating pyramid tiles failed: %s", err)
 		}
 	}

cmd/mtseeder/pyramid.go

@@ -6,6 +6,7 @@ package main
 
 import (
 	"image"
+	"image/color"
 	"image/draw"
 	"io/ioutil"
 	"log"
@@ -21,6 +22,12 @@ import (
 	"github.com/bamiaux/rez"
 )
 
+type pyramidCreator struct {
+	numWorkers int
+	outDir     string
+	bg         color.RGBA
+}
+
 func findMaxDir(files []os.FileInfo) (min, max int) {
 	min, max = math.MaxInt32, math.MinInt32
 	for _, file := range files {
@@ -64,7 +71,10 @@ type pyramidJob struct {
 	dst string
 }
 
-func createParentLevel(oldDir string, jobs chan pyramidJob) (newDir string, err error) {
+func (pc *pyramidCreator) createParentLevel(
+	oldDir string,
+	jobs chan pyramidJob) (newDir string, err error) {
+
 	oldName := filepath.Base(oldDir)
 
 	var oldLevel int
@@ -155,11 +165,14 @@ var dps = [4]image.Point{
 	image.Pt(256, 256),
 	image.Pt(256, 0)}
 
-func fuseTile(scratch, resized *image.RGBA, conv rez.Converter, job *pyramidJob) error {
+func (pc *pyramidCreator) fuseTile(
+	scratch, resized *image.RGBA,
+	conv rez.Converter,
+	job *pyramidJob) error {
 
 	for i, path := range job.src {
 
-		img := common.LoadPNG(path)
+		img := common.LoadPNG(path, pc.bg)
 
 		sr := clipRect(img.Bounds())
 		r := sr.Sub(sr.Min).Add(dps[i])
@@ -176,7 +189,7 @@ func fuseTile(scratch, resized *image.RGBA, conv rez.Converter, job *pyramidJob)
 	return common.SaveAsPNG(job.dst, resized)
 }
 
-func fuseTiles(jobs chan pyramidJob, done *sync.WaitGroup) {
+func (pc *pyramidCreator) fuseTiles(jobs chan pyramidJob, done *sync.WaitGroup) {
 	defer done.Done()
 	scratch := image.NewRGBA(image.Rect(0, 0, 512, 512))
 	resized := image.NewRGBA(image.Rect(0, 0, 256, 256))
@@ -194,41 +207,41 @@ func fuseTiles(jobs chan pyramidJob, done *sync.WaitGroup) {
 	}
 
 	for job := range jobs {
-		if err := fuseTile(scratch, resized, conv, &job); err != nil {
+		if err := pc.fuseTile(scratch, resized, conv, &job); err != nil {
 			log.Printf("WARN: Writing image failed: %s\n", err)
 		}
 	}
 }
 
-func createPyramid(outDir string, numWorker int) (err error) {
+func (pc *pyramidCreator) create() (err error) {
 
-	for oldDir := filepath.Join(outDir, baseLevelDir); oldDir != ""; {
-		if oldDir, err = createLevel(oldDir, numWorker); err != nil {
+	for oldDir := filepath.Join(pc.outDir, baseLevelDir); oldDir != ""; {
+		if oldDir, err = pc.createLevel(oldDir); err != nil {
 			return
 		}
 	}
 	return
 }
 
-func createLevel(oldDir string, numWorker int) (newDir string, err error) {
+func (pc *pyramidCreator) createLevel(oldDir string) (string, error) {
 
 	jobs := make(chan pyramidJob)
 
 	var done sync.WaitGroup
 
-	for i := 0; i < numWorker; i++ {
+	for i := 0; i < pc.numWorkers; i++ {
 		done.Add(1)
-		go fuseTiles(jobs, &done)
+		go pc.fuseTiles(jobs, &done)
 	}
 
-	newDir, err = createParentLevel(oldDir, jobs)
+	newDir, err := pc.createParentLevel(oldDir, jobs)
 	close(jobs)
 
 	if err != nil {
-		return
+		return newDir, err
 	}
 
 	done.Wait()
 
-	return
+	return newDir, err
 }