Stitching improvements

- Add integer downscale parameter
- Output information about the total bounding box
- Build workload chunks in a hilbert spiral to reduce memory consumption

.vscode/settings.json

@@ -1,8 +1,11 @@
 {
     "cSpell.words": [
+        "Lanczos",
         "Vogel",
+        "executables",
         "gridify",
         "hacky",
+        "hilbertify",
         "kbinani",
         "mapcap",
         "noita",

bin/stitch/imagetile.go

@@ -12,11 +12,15 @@ import (
 	"os"
 	"sync"
 	"time"
+
+	"github.com/nfnt/resize"
 )
 
 type imageTile struct {
 	fileName string
 
+	scaleDivider int // Downscales the coordinates and images on the fly.
+
 	offset image.Point // Correction offset of the image, so that it aligns pixel perfect with other images. Determined by image matching.
 
 	image         image.Image   // Either a rectangle or an RGBA image. The bounds of this image are determined by the filename.
@@ -59,6 +63,10 @@ func (it *imageTile) GetImage() (*image.RGBA, error) {
 		return &image.RGBA{}, err
 	}
 
+	if it.scaleDivider > 1 {
+		img = resize.Resize(uint(oldRect.Dx()), uint(oldRect.Dy()), img, resize.NearestNeighbor)
+	}
+
 	imgRGBA, ok := img.(*image.RGBA)
 	if !ok {
 		return &image.RGBA{}, fmt.Errorf("Expected an RGBA image, got %T instead", img)
@@ -72,7 +80,7 @@ func (it *imageTile) GetImage() (*image.RGBA, error) {
 	// Free the image after some time
 	go func() {
 		for it.imageUsedFlag {
-			time.Sleep(5 * time.Second)
+			time.Sleep(1 * time.Second)
 			it.imageUsedFlag = false
 		}
 

bin/stitch/imagetiles.go

@@ -37,9 +37,13 @@ type tilePairs map[tileAlignmentKeys]tileAlignment
 
 var regexFileParse = regexp.MustCompile(`^(-?\d+),(-?\d+).png$`)
 
-func loadImages(path string) ([]imageTile, error) {
+func loadImages(path string, scaleDivider int) ([]imageTile, error) {
 	var imageTiles []imageTile
 
+	if scaleDivider < 1 {
+		return nil, fmt.Errorf("Invalid scale of %v", scaleDivider)
+	}
+
 	files, err := filepath.Glob(filepath.Join(inputPath, "*.png"))
 	if err != nil {
 		return nil, err
@@ -66,9 +70,10 @@ func loadImages(path string) ([]imageTile, error) {
 		}
 
 		imageTiles = append(imageTiles, imageTile{
-			fileName:   file,
-			image:      image.Rect(x, y, x+width, y+height),
-			imageMutex: &sync.RWMutex{},
+			fileName:     file,
+			scaleDivider: scaleDivider,
+			image:        image.Rect(x/scaleDivider, y/scaleDivider, (x+width)/scaleDivider, (y+height)/scaleDivider),
+			imageMutex:   &sync.RWMutex{},
 		})
 	}
 
@@ -250,7 +255,11 @@ func (tp tilePairs) Stitch(tiles []imageTile, destImage *image.RGBA) error {
 // StitchGrid calls stitch, but divides the workload into a grid of chunks.
 // Additionally it runs the workload multithreaded.
 func (tp tilePairs) StitchGrid(tiles []imageTile, destImage *image.RGBA, gridSize int) (errResult error) {
-	workloads := gridifyRectangle(destImage.Bounds(), gridSize)
+	//workloads := gridifyRectangle(destImage.Bounds(), gridSize)
+	workloads, err := hilbertifyRectangle(destImage.Bounds(), gridSize)
+	if err != nil {
+		return err
+	}
 
 	bar := progressbar.New(len(workloads))
 	bar.RenderBlank()

bin/stitch/stitch.go

@@ -17,12 +17,22 @@ var inputPath = filepath.Join(".", "..", "..", "output")
 
 func main() {
 	log.Printf("Starting to read tile information at \"%v\"", inputPath)
-	tiles, err := loadImages(inputPath)
+	tiles, err := loadImages(inputPath, 2)
 	if err != nil {
 		log.Panic(err)
 	}
 	log.Printf("Got %v tiles", len(tiles))
 
+	totalBounds := image.Rectangle{}
+	for i, tile := range tiles {
+		if i == 0 {
+			totalBounds = tile.Bounds()
+		} else {
+			totalBounds = totalBounds.Union(tile.Bounds())
+		}
+	}
+	log.Printf("Total size of the possible output space is %v", totalBounds)
+
 	/*profFile, err := os.Create("cpu.prof")
 	if err != nil {
 		log.Panicf("could not create CPU profile: %v", err)
@@ -35,14 +45,14 @@ func main() {
 
 	// TODO: Flags / Program arguments
 
-	outputRect := image.Rect(-35000, -35000, 35000, 35000)
+	outputRect := image.Rect(-1900*2, -1900*2, 1900*2, 1900*2)
 
 	log.Printf("Creating output image with a size of %v", outputRect.Size())
 	outputImage := image.NewRGBA(outputRect)
 
 	log.Printf("Stitching %v tiles into an image at %v", len(tiles), outputImage.Bounds())
 	tp := make(tilePairs)
-	if err := tp.StitchGrid(tiles, outputImage, 1024); err != nil {
+	if err := tp.StitchGrid(tiles, outputImage, 512); err != nil {
 		log.Panic(err)
 	}
 

bin/stitch/util.go

@@ -11,10 +11,13 @@ import (
 	"image/color"
 	"math"
 	"os"
+	"sort"
 
 	"golang.org/x/image/font"
 	"golang.org/x/image/font/basicfont"
 	"golang.org/x/image/math/fixed"
+
+	"github.com/google/hilbert"
 )
 
 // Source: https://gist.github.com/sergiotapia/7882944
@@ -75,6 +78,31 @@ func gridifyRectangle(rect image.Rectangle, gridSize int) (result []image.Rectan
 	return
 }
 
+func hilbertifyRectangle(rect image.Rectangle, gridSize int) ([]image.Rectangle, error) {
+	grid := gridifyRectangle(rect, gridSize)
+
+	gridX := divideFloor(rect.Min.X, gridSize)
+	gridY := divideFloor(rect.Min.Y, gridSize)
+
+	// Size of the grid in chunks
+	gridWidth := divideCeil(rect.Max.X, gridSize) - divideFloor(rect.Min.X, gridSize)
+	gridHeight := divideCeil(rect.Max.Y, gridSize) - divideFloor(rect.Min.Y, gridSize)
+
+	s, err := hilbert.NewHilbert(int(math.Pow(2, math.Ceil(math.Log2(math.Max(float64(gridWidth), float64(gridHeight)))))))
+	if err != nil {
+		return nil, err
+	}
+
+	sort.Slice(grid, func(i, j int) bool {
+		// Ignore out of range errors, as they shouldn't happen.
+		hilbertIndexA, _ := s.MapInverse(grid[i].Min.X/gridSize-gridX, grid[i].Min.Y/gridSize-gridY)
+		hilbertIndexB, _ := s.MapInverse(grid[j].Min.X/gridSize-gridX, grid[j].Min.Y/gridSize-gridY)
+		return hilbertIndexA < hilbertIndexB
+	})
+
+	return grid, nil
+}
+
 func drawLabel(img *image.RGBA, x, y int, label string) {
 	col := color.RGBA{200, 100, 0, 255}
 	point := fixed.Point26_6{X: fixed.Int26_6(x * 64), Y: fixed.Int26_6(y * 64)}
@@ -105,7 +133,7 @@ func pointAbs(p image.Point) image.Point {
 	return p
 }
 
-// Integer division that rounds to the next integer towards negative infinity
+// Integer division that rounds to the next integer towards negative infinity.
 func divideFloor(a, b int) int {
 	temp := a / b
 
@@ -116,7 +144,7 @@ func divideFloor(a, b int) int {
 	return temp
 }
 
-// Integer division that rounds to the next integer towards positive infinity
+// Integer division that rounds to the next integer towards positive infinity.
 func divideCeil(a, b int) int {
 	temp := a / b
 
@@ -126,3 +154,10 @@ func divideCeil(a, b int) int {
 
 	return temp
 }
+
+func maxInt(x, y int) int {
+	if x > y {
+		return x
+	}
+	return y
+}

go.mod

@@ -5,8 +5,10 @@ go 1.13
 require (
 	github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802 // indirect
 	github.com/gen2brain/shm v0.0.0-20180314170312-6c18ff7f8b90 // indirect
+	github.com/google/hilbert v0.0.0-20181122061418-320f2e35a565
 	github.com/kbinani/screenshot v0.0.0-20190719135742-f06580e30cdc
 	github.com/lxn/win v0.0.0-20190919090605-24c5960b03d8 // indirect
+	github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646
 	github.com/schollz/progressbar/v2 v2.14.0
 	golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8
 )

go.sum

@@ -5,12 +5,16 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/gen2brain/shm v0.0.0-20180314170312-6c18ff7f8b90 h1:QagTG5rauLt6pVVEhnVSrlIX4ifhVIZOwmw6x6D8TUw=
 github.com/gen2brain/shm v0.0.0-20180314170312-6c18ff7f8b90/go.mod h1:uF6rMu/1nvu+5DpiRLwusA6xB8zlkNoGzKn8lmYONUo=
+github.com/google/hilbert v0.0.0-20181122061418-320f2e35a565 h1:KBAlCAY6eLC44FiEwbzEbHnpVlw15iVM4ZK8QpRIp4U=
+github.com/google/hilbert v0.0.0-20181122061418-320f2e35a565/go.mod h1:xn6EodFfRzV6j8NXQRPjngeHWlrpOrsZPKuuLRThU1k=
 github.com/kbinani/screenshot v0.0.0-20190719135742-f06580e30cdc h1:kGFotla6Dyr6a2ILeExAHlttPgJtnoP/GIw2uVN/4h4=
 github.com/kbinani/screenshot v0.0.0-20190719135742-f06580e30cdc/go.mod h1:f8GY5V3lRzakvEyr49P7hHRYoHtPr8zvj/7JodCoRzw=
 github.com/lxn/win v0.0.0-20190919090605-24c5960b03d8 h1:RVMGIuuNgrpGB7I79f6xfhGCkpN47IaEGh8VTM0p7Xc=
 github.com/lxn/win v0.0.0-20190919090605-24c5960b03d8/go.mod h1:ouWl4wViUNh8tPSIwxTVMuS014WakR1hqvBc2I0bMoA=
 github.com/mitchellh/colorstring v0.0.0-20190213212951-d06e56a500db h1:62I3jR2EmQ4l5rM/4FEfDWcRD+abF5XlKShorW5LRoQ=
 github.com/mitchellh/colorstring v0.0.0-20190213212951-d06e56a500db/go.mod h1:l0dey0ia/Uv7NcFFVbCLtqEBQbrT4OCwCSKTEv6enCw=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 h1:zYyBkD/k9seD2A7fsi6Oo2LfFZAehjjQMERAvZLEDnQ=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/schollz/progressbar/v2 v2.14.0 h1:vo7bdkI9E4/CIk9DnL5uVIaybLQiVtiCC2vO+u9j5IM=