Added a simplifed go based render

Initial simplifed go based render. Does not do
everything that original render does, but is able
to generate a png, based on OSMesa.

cmd/snapshot_simple/main.go

@@ -0,0 +1,189 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"image"
+	"image/png"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/go-spatial/geom"
+	"github.com/go-spatial/geom/slippy"
+	mbgl "github.com/go-spatial/go-mbgl/mbgl/simplified"
+)
+
+/*
+snapshotter bounds "lat long lat long" -width=100, -height=100 style filename.png
+snapshotter tile "z/x/y" style filename.png
+*/
+
+type cmdType uint8
+
+const (
+	CmdUnknown = cmdType(iota)
+	CmdBounds
+	CmdTile
+)
+
+func (c cmdType) String() string {
+	switch c {
+	case CmdBounds:
+		return "Bounds"
+	case CmdTile:
+		return "Tile"
+	default:
+		return "Unknown"
+	}
+}
+
+var FWidth uint
+var FHeight uint
+var FStyle string
+var FPixelRatio float64
+
+var FBounds geom.Extent
+var FTile slippy.Tile
+var FOutputFilename string
+
+func usage() {
+	fmt.Fprintf(os.Stderr, "%v [options...] \"lat long lat long\" output_filename.png\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "%v [options...] bounds \"lat long lat long\" output_filename.png\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "%v [options...] tile \"z/x/y\" output_filename.png\n", os.Args[0])
+	flag.PrintDefaults()
+}
+
+func parseBounds(boundString string) {
+	var err error
+	bounds := strings.Split(boundString, " ")
+	if len(bounds) != 4 {
+		fmt.Fprintf(os.Stderr, "Error: invalid bounds provided — %v\n", boundString)
+		usage()
+		os.Exit(2)
+	}
+	for i, bound := range bounds {
+		FBounds[i], err = strconv.ParseFloat(strings.TrimSpace(bound), 64)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Error: invalid bounds provided — %v\n", boundString)
+			fmt.Fprintf(os.Stderr, "Error: unabled to parse %v(%v) as a float.\n", bound, i)
+			usage()
+			os.Exit(2)
+		}
+	}
+}
+
+func parseTile(tileString string) {
+	var err error
+	var v uint64
+	parts := strings.Split(tileString, "/")
+	if len(parts) != 3 {
+		fmt.Fprintf(os.Stderr, "Error: invalid z/x/y coordinates  — %v\n", tileString)
+		usage()
+		os.Exit(2)
+	}
+	var label = [...]string{"Z", "X", "Y"}
+
+	for i, part := range parts {
+		v, err = strconv.ParseUint(strings.TrimSpace(part), 10, 64)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Error: invalid tile coordinates provided — %v\n", tileString)
+			fmt.Fprintf(os.Stderr, "Error: unabled to parse %v %v as a uint.\n", label[i], part)
+			usage()
+			os.Exit(2)
+		}
+		switch i {
+		case 0:
+			FTile.Z = uint(v)
+		case 1:
+			FTile.X = uint(v)
+		case 2:
+			FTile.Y = uint(v)
+		}
+	}
+}
+
+func ParseFlags() cmdType {
+
+	flag.UintVar(&FWidth, "width", 512, "Width of the image to generate.")
+	flag.UintVar(&FWidth, "w", 512, "Width of the image to generate.")
+
+	flag.UintVar(&FHeight, "height", 512, "Height of the image to generate.")
+	flag.UintVar(&FHeight, "h", 512, "Height of the image to generate.")
+
+	flag.StringVar(&FStyle, "style", "file://style.json", "Style file")
+	flag.Float64Var(&FPixelRatio, "pixel", 1.0, "The pixel ratio")
+
+	flag.Parse()
+
+	if flag.NArg() < 3 {
+		usage()
+		os.Exit(2)
+	}
+
+	var cmd cmdType
+	var fileIdx = 2
+
+	switch strings.TrimSpace(strings.ToLower(flag.Arg(0))) {
+	case "bounds":
+		// The next variable should be the bounds seperated by spaces.
+		parseBounds(flag.Arg(1))
+		cmd = CmdBounds
+	case "tile":
+		// The next variable should be the coordinates sepearted by forward slash.
+		parseTile(flag.Arg(1))
+
+		cmd = CmdTile
+	default: // assume bounds as the default subcommand
+		parseBounds(flag.Arg(0))
+		fileIdx = 1
+		cmd = CmdBounds
+	}
+
+	// Next should be the output filename.
+	FOutputFilename = strings.TrimSpace(flag.Arg(fileIdx))
+	return cmd
+
+}
+
+func main() {
+	var file *os.File
+	var err error
+	var img image.Image
+	_ = ParseFlags()
+	snpsht := mbgl.Snapshotter{
+		Style:    FStyle,
+		Width:    uint32(FWidth),
+		Height:   uint32(FHeight),
+		PPIRatio: int(FPixelRatio),
+	}
+	img, err = mbgl.Snapshot(snpsht)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "got an error creating the snapshot: %v\n", err)
+		os.Exit(3)
+	}
+	/*
+		switch cmd {
+		case CmdBounds:
+			img = ss.Snapshot(&FBounds, size)
+
+		case CmdTile:
+			img = mbgl.SnapshotTile(ss, FTile, size)
+
+		}
+	*/
+	file, err = os.Create(FOutputFilename)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error creating output file: %v -- %v\n", FOutputFilename, err)
+		os.Exit(3)
+	}
+	defer file.Close()
+	if err := png.Encode(file, img); err != nil {
+		log.Printf("Failed to write %v", FOutputFilename)
+		log.Println(err)
+		return
+	}
+
+	fmt.Printf("successfully wrote outfile: %v\n", FOutputFilename)
+}

cmd/snapshot_simple/style.json

@@ -0,0 +1 @@
+{"version":8,"name":"osm","center":[-76.275329586789,39.153492567373],"zoom":8,"sources":{"osm":{"type":"vector","url":"https://osm.tegola.io/capabilities/osm.json"}},"layers":[{"id":"populated_places","source":"osm","source-layer":"populated_places","type":"circle","layout":{"visibility":"visible"},"paint":{"circle-radius":3,"circle-color":"#71ab62"}},{"id":"country_lines","source":"osm","source-layer":"country_lines","type":"line","layout":{"visibility":"visible"},"paint":{"line-color":"#168120"}},{"id":"country_lines_disputed","source":"osm","source-layer":"country_lines_disputed","type":"line","layout":{"visibility":"visible"},"paint":{"line-color":"#29e597"}},{"id":"country_label_points","source":"osm","source-layer":"country_label_points","type":"circle","layout":{"visibility":"visible"},"paint":{"circle-radius":3,"circle-color":"#9776f3"}},{"id":"country_polygons","source":"osm","source-layer":"country_polygons","type":"fill","layout":{"visibility":"visible"},"paint":{"fill-color":"rgba(2,85,36,0.1)","fill-outline-color":"#025524"}},{"id":"state_lines","source":"osm","source-layer":"state_lines","type":"line","layout":{"visibility":"visible"},"paint":{"line-color":"#d1050f"}},{"id":"land","source":"osm","source-layer":"land","type":"fill","layout":{"visibility":"visible"},"paint":{"fill-color":"rgba(235,145,50,0.1)","fill-outline-color":"#eb9132"}},{"id":"admin_lines","source":"osm","source-layer":"admin_lines","type":"fill","layout":{"visibility":"visible"},"paint":{"fill-color":"rgba(15,190,3,0.1)","fill-outline-color":"#0fbe03"}},{"id":"state_label_points","source":"osm","source-layer":"state_label_points","type":"circle","layout":{"visibility":"visible"},"paint":{"circle-radius":3,"circle-color":"#7c39e4"}},{"id":"landuse_areas","source":"osm","source-layer":"landuse_areas","type":"fill","layout":{"visibility":"visible"},"paint":{"fill-color":"rgba(67,79,119,0.1)","fill-outline-color":"#434f77"}},{"id":"water_areas","source":"osm","source-layer":"water_areas","type":"fill","layout":{"visibility":"visible"},"paint":{"fill-color":"rgba(94,252,42,0.1)","fill-outline-color":"#5efc2a"}},{"id":"water_lines","source":"osm","source-layer":"water_lines","type":"line","layout":{"visibility":"visible"},"paint":{"line-color":"#d709c2"}},{"id":"transport_lines","source":"osm","source-layer":"transport_lines","type":"line","layout":{"visibility":"visible"},"paint":{"line-color":"#69e68c"}},{"id":"transport_areas","source":"osm","source-layer":"transport_areas","type":"fill","layout":{"visibility":"visible"},"paint":{"fill-color":"rgba(240,216,245,0.1)","fill-outline-color":"#f0d8f5"}},{"id":"transport_points","source":"osm","source-layer":"transport_points","type":"circle","layout":{"visibility":"visible"},"paint":{"circle-radius":3,"circle-color":"#b9b235"}},{"id":"amenity_areas","source":"osm","source-layer":"amenity_areas","type":"fill","layout":{"visibility":"visible"},"paint":{"fill-color":"rgba(128,132,166,0.1)","fill-outline-color":"#8084a6"}},{"id":"amenity_points","source":"osm","source-layer":"amenity_points","type":"circle","layout":{"visibility":"visible"},"paint":{"circle-radius":3,"circle-color":"#29799a"}},{"id":"other_points","source":"osm","source-layer":"other_points","type":"circle","layout":{"visibility":"visible"},"paint":{"circle-radius":3,"circle-color":"#f2c89f"}},{"id":"other_lines","source":"osm","source-layer":"other_lines","type":"line","layout":{"visibility":"visible"},"paint":{"line-color":"#10a5da"}},{"id":"other_areas","source":"osm","source-layer":"other_areas","type":"fill","layout":{"visibility":"visible"},"paint":{"fill-color":"rgba(151,151,67,0.1)","fill-outline-color":"#979743"}},{"id":"buildings","source":"osm","source-layer":"buildings","type":"fill","layout":{"visibility":"visible"},"paint":{"fill-color":"rgba(63,68,136,0.1)","fill-outline-color":"#3f4488"}}]}

mbgl/c/bin/render_stripped.cpp

@@ -13,35 +13,89 @@
 #include <iostream>
 #include <fstream>
 
+
+struct snapshot_params {
+	std::string style;
+	std::string cache_file;
+	std::string asset_root;
+	uint32_t width;
+	uint32_t height;
+	int ppi_ratio;
+	double lat;
+	double lng;
+	double zoom;
+	double pitch;
+	double bearing;
+};
+
+struct snapshot_result {
+	mbgl::PremultipliedImage image;
+	bool did_error;
+	std::string err;
+};
+
+
+struct snapshot_result snapshot( struct snapshot_params params ) {
+
+    struct snapshot_result result; 
+    result.did_error = false;
+
+    mbgl::ThreadPool threadPool(4);
+
+    mbgl::DefaultFileSource fileSource(params.cache_file, params.asset_root);
+    mbgl::HeadlessFrontend frontend({ params.height, params.width }, params.ppi_ratio, fileSource, threadPool);
+
+    mbgl::Map map(frontend, mbgl::MapObserver::nullObserver(), frontend.getSize(), params.ppi_ratio, fileSource, threadPool, mbgl::MapMode::Static);
+
+    //map.getStyle().loadURL("file://style.json");
+    map.getStyle().loadURL(params.style);
+    map.setLatLngZoom({ params.lat, params.lng }, params.zoom);
+    map.setBearing(params.bearing);
+    map.setPitch(params.pitch);
+
+    try {
+	result.image = frontend.render(map);
+    } catch(std::exception& e) {
+	result.did_error = true;
+	result.err = e.what();
+    }
+    return result;
+}
+
+
 int main(int argc __attribute__((unused)), char *argv[] __attribute__((unused)) ) {
     const std::string output     = "out.png";
-    const std::string cache_file = "cache.sqlite";
-    const std::string asset_root = ".";
 
     using namespace mbgl;
 
     util::RunLoop loop;
 
-    DefaultFileSource fileSource(cache_file, asset_root);
-    ThreadPool threadPool(4);
-    HeadlessFrontend frontend({ 512, 512 }, 1, fileSource, threadPool);
-    Map map(frontend, MapObserver::nullObserver(), frontend.getSize(), 1, fileSource, threadPool, MapMode::Static);
-
-
-    map.getStyle().loadURL("file://style.json");
-    map.setLatLngZoom({ 0, 0 }, 0);
-    map.setBearing(0);
-    map.setPitch(0);
-
+    struct snapshot_params snpParams;
+    snpParams.cache_file = "cache.sqlite";
+    snpParams.asset_root = ".";
+    snpParams.style = "file://style.json";
+    snpParams.width = 512;
+    snpParams.height = 512;
+    snpParams.ppi_ratio = 1;
+    snpParams.lat = 0;
+    snpParams.lng = 0;
+    snpParams.zoom = 0;
+    snpParams.pitch = 0;
+    snpParams.bearing = 0;
 
+    struct snapshot_result ret;
+    ret = snapshot(snpParams);
+    if(ret.did_error){
+	    std::cout << "Error :" << ret.err << std::endl;
+	    exit(1);
+    }
     try {
         std::ofstream out(output, std::ios::binary);
-        out << encodePNG(frontend.render(map));
+        out << encodePNG(ret.image);
         out.close();
-    } catch(std::exception& e) {
-        std::cout << "Error: " << e.what() << std::endl;
-        exit(1);
+    }catch(std::exception& e) {
+	    std::cout << "Error :" << e.what() << std::endl;
+	    exit(1);
     }
-
     return 0;
 }

mbgl/c/build_render_with_local.sh

@@ -0,0 +1,61 @@
+#!/bin/bash -e
+
+echo "Building the object file."
+
+g++ \
+	-DRAPIDJSON_HAS_STDSTRING=1 \
+	-D_GLIBCXX_USE_CXX11_ABI=1 \
+	-Iinclude \
+	-ftemplate-depth=1024 \
+	-Wall \
+	-Wextra \
+	-Wshadow \
+	-Wnon-virtual-dtor \
+	-Wno-variadic-macros \
+	-Wno-unknown-pragmas \
+	-Werror \
+	-fext-numeric-literals \
+	-g \
+	-fPIE \
+	-fvisibility=hidden \
+	-fvisibility-inlines-hidden \
+	-std=c++14 \
+	-o bin/render_stripped.cpp.o \
+	-c bin/render_stripped.cpp
+
+
+echo "Building executable."
+
+# libmbgl-core.a libmbgl-filesource.a libmbgl-loop-uv.a libsqlite.a -Wl,--no-as-needed -lcurl -Wl,--as-needed libmbgl-core.a -lOSMesa ../../../mason_packages/linux-x86_64/libpng/1.6.25/lib/libpng.a -lz -lm ../../../mason_packages/linux-x86_64/libjpeg-turbo/1.5.0/lib/libjpeg.a libnunicode.a libicu.a -lz -static-libstdc++ -Wl,-Bsymbolic-functions ../../../mason_packages/linux-x86_64/libuv/1.9.1/lib/libuv.a -lrt -lpthread -lnsl -ldl
+
+g++ \
+	-ftemplate-depth=1024 \
+	-Wall \
+	-Wextra \
+	-Wshadow \
+	-Wnon-virtual-dtor \
+	-Wno-variadic-macros \
+	-Wno-unknown-pragmas \
+	-Werror -fext-numeric-literals \
+	-static-libstdc++ \
+	-g bin/render_stripped.cpp.o \
+	lib/linux/libmbgl-core.a \
+	lib/linux/libmbgl-filesource.a \
+	lib/linux/libmbgl-loop-uv.a \
+	lib/linux/libsqlite.a \
+	-Wl,--no-as-needed -lcurl \
+	-Wl,--as-needed lib/linux/libmbgl-core.a \
+	-lOSMesa \
+	lib/linux/libpng.a \
+	-lz \
+	-lm \
+	lib/linux/libjpeg.a \
+	lib/linux/libnunicode.a \
+	lib/linux/libicu.a \
+	-Wl,-Bsymbolic-functions lib/linux/libuv.a \
+	-lrt \
+	-lpthread \
+	-lnsl \
+	-ldl \
+	-o bin/mbgl-render-stripped \
+