Add pngOptions and preRenderFn options

- see consbio#26 for preRenderFn.
- pngOptions are passed to the sharp.png() method as is.

Author: meowcoder

dist/render.js

@@ -377,7 +377,8 @@ var getRemoteAsset = function getRemoteAsset(url, callback) {
  * @param {number} width - width of output map (default: 1024)
  * @param {number} height - height of output map (default: 1024)
  * @param {Object} - configuration object containing style, zoom, center: [lng, lat],
- * width, height, bounds: [west, south, east, north], ratio, padding, skipEncoding
+ * width, height, bounds: [west, south, east, north], ratio, padding, skipEncoding,
+ * preRenderFn, pngOptions
  * @param {String} tilePath - path to directory containing local mbtiles files that are
  * referenced from the style.json as "mbtiles://<tileset>"
  */
@@ -401,7 +402,10 @@ var render = function render(style) {
         _options$padding = options.padding,
         padding = _options$padding === void 0 ? 0 : _options$padding,
         _options$skipEncoding = options.skipEncoding,
-        skipEncoding = _options$skipEncoding === void 0 ? false : _options$skipEncoding;
+        skipEncoding = _options$skipEncoding === void 0 ? false : _options$skipEncoding,
+        _options$preRenderFn = options.preRenderFn,
+        preRenderFn = _options$preRenderFn === void 0 ? null : _options$preRenderFn,
+        pngOptions = options.pngOptions;
     var _options$center = options.center,
         center = _options$center === void 0 ? null : _options$center,
         _options$zoom = options.zoom,
@@ -589,6 +593,11 @@ var render = function render(style) {
     };
     var map = new _mapboxGlNative["default"].Map(mapOptions);
     map.load(style);
+
+    if (typeof preRenderFn === 'function') {
+      preRenderFn(map);
+    }
+
     map.render({
       zoom: zoom,
       center: center,
@@ -637,7 +646,7 @@ var render = function render(style) {
             height: height * ratio,
             channels: 4
           }
-        }).png().toBuffer().then(resolve)["catch"](reject);
+        }).png(pngOptions).toBuffer().then(resolve)["catch"](reject);
       } catch (pngErr) {
         console.error('Error encoding PNG');
         console.error(pngErr);

dist/server.js

@@ -77,6 +77,10 @@ var PARAMS = {
   token: {
     isRequired: false,
     isString: true
+  },
+  pngOptions: {
+    isRequired: false,
+    isObject: true
   }
 };
 
@@ -90,7 +94,8 @@ var renderImage = function renderImage(params, response, next, tilePath) {
       _params$bearing = params.bearing,
       bearing = _params$bearing === void 0 ? null : _params$bearing,
       _params$pitch = params.pitch,
-      pitch = _params$pitch === void 0 ? null : _params$pitch;
+      pitch = _params$pitch === void 0 ? null : _params$pitch,
+      pngOptions = params.pngOptions;
   var style = params.style,
       _params$zoom = params.zoom,
       zoom = _params$zoom === void 0 ? null : _params$zoom,
@@ -235,7 +240,8 @@ var renderImage = function renderImage(params, response, next, tilePath) {
       ratio: ratio,
       bearing: bearing,
       pitch: pitch,
-      token: token
+      token: token,
+      pngOptions: pngOptions
     }).then(function (data, rejected) {
       if (rejected) {
         console.error('render request rejected', rejected);

src/render.js

@@ -320,7 +320,8 @@ const getRemoteAsset = (url, callback) => {
  * @param {number} width - width of output map (default: 1024)
  * @param {number} height - height of output map (default: 1024)
  * @param {Object} - configuration object containing style, zoom, center: [lng, lat],
- * width, height, bounds: [west, south, east, north], ratio, padding, skipEncoding
+ * width, height, bounds: [west, south, east, north], ratio, padding, skipEncoding,
+ * preRenderFn, pngOptions
  * @param {String} tilePath - path to directory containing local mbtiles files that are
  * referenced from the style.json as "mbtiles://<tileset>"
  */
@@ -334,6 +335,8 @@ export const render = (style, width = 1024, height = 1024, options) =>
             ratio = 1,
             padding = 0,
             skipEncoding = false,
+            preRenderFn = null,
+            pngOptions,
         } = options
         let { center = null, zoom = null, tilePath = null } = options
 
@@ -553,6 +556,10 @@ export const render = (style, width = 1024, height = 1024, options) =>
         const map = new mbgl.Map(mapOptions)
         map.load(style)
 
+        if (typeof preRenderFn === 'function') {
+            preRenderFn(map)
+        }
+
         map.render(
             {
                 zoom,
@@ -603,7 +610,7 @@ export const render = (style, width = 1024, height = 1024, options) =>
                             channels: 4,
                         },
                     })
-                        .png()
+                        .png(pngOptions)
                         .toBuffer()
                         .then(resolve)
                         .catch(reject)

src/server.js

@@ -28,6 +28,7 @@ const PARAMS = {
     bearing: { isRequired: false, isDecimal: true },
     pitch: { isRequired: false, isDecimal: true },
     token: { isRequired: false, isString: true },
+    pngOptions: { isRequired: false, isObject: true },
 }
 
 const renderImage = (params, response, next, tilePath) => {
@@ -38,6 +39,7 @@ const renderImage = (params, response, next, tilePath) => {
         padding = 0,
         bearing = null,
         pitch = null,
+        pngOptions,
     } = params
     let { style, zoom = null, center = null, bounds = null, ratio = 1 } = params
 
@@ -206,6 +208,7 @@ const renderImage = (params, response, next, tilePath) => {
             bearing,
             pitch,
             token,
+            pngOptions,
         })
             .then((data, rejected) => {
                 if (rejected) {