initial

5 files changed, 191 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..723ef36
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.idea
\ No newline at end of file
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..59a005b
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,8 @@
+module OsmStatic
+
+go 1.14
+
+require (
+	github.com/disintegration/imaging v1.6.2
+	github.com/labstack/echo/v4 v4.1.16
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..d8fca54
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,49 @@
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
+github.com/disintegration/imaging v1.6.2 h1:w1LecBlG2Lnp8B3jk5zSuNqd7b4DXhcjwek1ei82L+c=
+github.com/disintegration/imaging v1.6.2/go.mod h1:44/5580QXChDfwIclfc/PCwrr44amcmDAg8hxG0Ewe4=
+github.com/labstack/echo/v4 v4.1.16 h1:8swiwjE5Jkai3RPfZoahp8kjVCRNq+y7Q0hPji2Kz0o=
+github.com/labstack/echo/v4 v4.1.16/go.mod h1:awO+5TzAjvL8XpibdsfXxPgHr+orhtXZJZIQCVjogKI=
+github.com/labstack/gommon v0.3.0 h1:JEeO0bvc78PKdyHxloTKiF8BD5iGrH8T6MSeGvSgob0=
+github.com/labstack/gommon v0.3.0/go.mod h1:MULnywXg0yavhxWKc+lOruYdAhDwPK9wf0OL7NoOu+k=
+github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
+github.com/mattn/go-colorable v0.1.6 h1:6Su7aK7lXmJ/U79bYtBjLNaha4Fs1Rg9plHpcH+vvnE=
+github.com/mattn/go-colorable v0.1.6/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
+github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
+github.com/mattn/go-isatty v0.0.9/go.mod h1:YNRxwqDuOph6SZLI9vUUz6OYw3QyUt7WiY2yME+cCiQ=
+github.com/mattn/go-isatty v0.0.12 h1:wuysRhFDzyxgEmMf5xjvJ2M9dZoWAXNNr5LSBS7uHXY=
+github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
+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/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/valyala/bytebufferpool v1.0.0 h1:GqA5TC/0021Y/b9FG4Oi9Mr3q7XYx6KllzawFIhcdPw=
+github.com/valyala/bytebufferpool v1.0.0/go.mod h1:6bBcMArwyJ5K/AmCkWv1jt77kVWyCJ6HpOuEn7z0Csc=
+github.com/valyala/fasttemplate v1.0.1/go.mod h1:UQGH1tvbgY+Nz5t2n7tXsz52dQxojPUpymEIMZ47gx8=
+github.com/valyala/fasttemplate v1.1.0 h1:RZqt0yGBsps8NGvLSGW804QQqCUYYLsaOjTVHy1Ocw4=
+github.com/valyala/fasttemplate v1.1.0/go.mod h1:UQGH1tvbgY+Nz5t2n7tXsz52dQxojPUpymEIMZ47gx8=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20200221231518-2aa609cf4a9d h1:1ZiEyfaQIg3Qh0EoqpwAakHVhecoE5wlSg5GjnafJGw=
+golang.org/x/crypto v0.0.0-20200221231518-2aa609cf4a9d/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8 h1:hVwzHzIUGRjiF7EcUjqNxk3NCfkPxbDKRdnNE1Rpg0U=
+golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20200226121028-0de0cce0169b h1:0mm1VjtFUOIlE1SbDlwjYaDxZVDP2S5ou6y0gSgXHu8=
+golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
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+golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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+golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae h1:/WDfKMnPU+m5M4xB+6x4kaepxRw6jWvR5iDRdvjHgy8=
+golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
+golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..349f41c
--- /dev/null
+++ b/main.go
@@ -0,0 +1,45 @@
+package main
+
+import (
+	"github.com/labstack/echo/v4"
+	"log"
+	"strconv"
+)
+
+func main() {
+	e := echo.New()
+	e.GET("/map", func(c echo.Context) error {
+		lat, err := strconv.ParseFloat(c.QueryParam("lat"), 64)
+		if err != nil {
+			return err
+		}
+		lon, err := strconv.ParseFloat(c.QueryParam("lon"), 64)
+		if err != nil {
+			return err
+		}
+		w, err := strconv.Atoi(c.QueryParam("w"))
+		if err != nil {
+			w = 800
+		}
+		h, err := strconv.Atoi(c.QueryParam("h"))
+		if err != nil {
+			h = 800
+		}
+		zoom, err := strconv.Atoi(c.QueryParam("zoom"))
+		if err != nil {
+			zoom = 16
+		}
+		if zoom < 1 {
+			zoom = 1
+		}
+		if zoom > 20 {
+			zoom = 20
+		}
+		img, err := GetMapImage(lat, lon, zoom, w, h)
+		if err != nil {
+			return err
+		}
+		return c.Blob(200, "image/png", img)
+	})
+	log.Fatal(e.Start(":8000"))
+}
diff --git a/map.go b/map.go
new file mode 100644
index 0000000..baa9356
--- /dev/null
+++ b/map.go
@@ -0,0 +1,88 @@
+/*
+Copyright © 2020 Alexander Kiryukhin <ak@bytechain.ru>
+This file is part of OsmStatic project.
+*/
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"image"
+	"image/color"
+	"image/png"
+	_ "image/png"
+	"io/ioutil"
+	"log"
+	"math"
+	"net/http"
+	"sync"
+
+	"github.com/disintegration/imaging"
+)
+
+const (
+	tileAddr = `https://a.tile.openstreetmap.org/%d/%d/%d.png`
+	tw       = 256
+	th       = 256
+)
+
+func GetMapImage(lat, lon float64, zoom, width, height int) ([]byte, error) {
+	x, y, dx, dy := getCoords(lat, lon, zoom)
+	dst := imaging.New(width, height, color.NRGBA{0, 255, 0, 255})
+	wg := sync.WaitGroup{}
+	mu := sync.Mutex{}
+	cx := width/2 - tw/2
+	cy := height/2 - th/2
+	sx := width/tw + 2
+	sy := height/th + 2
+	di := int(dx*float64(tw)) - tw/2
+	dj := int(dy*float64(th)) - th/2
+	for i := -sx / 2; i <= sx/2; i++ {
+		for j := -sy / 2; j <= sy/2; j++ {
+			wg.Add(1)
+			go func(i, j int) {
+				defer wg.Done()
+				tile, err := getTile(x+i, y+j, zoom)
+				if err != nil {
+					log.Println(err)
+					return
+				}
+				img, err := png.Decode(bytes.NewReader(tile))
+				if err != nil {
+					log.Println(err)
+					return
+				}
+				mu.Lock()
+				defer mu.Unlock()
+				tx := cx + i*tw - di
+				ty := cy + j*th - dj
+				dst = imaging.Paste(dst, img, image.Pt(tx, ty))
+			}(int(i), int(j))
+		}
+	}
+	wg.Wait()
+
+	out := bytes.NewBuffer([]byte{})
+	if err := imaging.Encode(out, dst, imaging.PNG); err != nil {
+		return nil, err
+	}
+	return out.Bytes(), nil
+}
+
+func getCoords(lat, lon float64, zoom int) (int, int, float64, float64) {
+	x := (lon + 180.0) / 360.0 * (math.Exp2(float64(zoom)))
+	y := (1.0 - math.Log(math.Tan(lat*math.Pi/180.0)+1.0/math.Cos(lat*math.Pi/180.0))/math.Pi) / 2.0 * (math.Exp2(float64(zoom)))
+	dx := x - math.Floor(x)
+	dy := y - math.Floor(y)
+	return int(math.Floor(x)), int(math.Floor(y)), dx, dy
+}
+
+func getTile(x, y, z int) ([]byte, error) {
+	tile := fmt.Sprintf(tileAddr, z, x, y)
+	resp, err := http.DefaultClient.Get(tile)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+	return ioutil.ReadAll(resp.Body)
+}