Add Typescript definitions

package.json

@@ -5,6 +5,7 @@
   "main": "dist/georaster.bundle.min.js",
   "browser": "./dist/georaster.browser.bundle.min.js",
   "unpkg": "./dist/georaster.browser.bundle.min.js",
+  "types": "dist/georaster.d.ts",
   "scripts": {
     "analyze": "ANALYZE_GEORASTER_BUNDLE=true npm run build",
     "clean": "rm -f ./dist/*",
@@ -16,10 +17,11 @@
     "test-dev": "npm run dev && GEORASTER_TEST_BUNDLE_NAME='georaster.bundle.js' node ./node_modules/.bin/mocha --reporter spec",
     "test-prod": "npm run build && GEORASTER_TEST_BUNDLE_NAME='georaster.bundle.min.js' node ./node_modules/.bin/mocha --reporter spec",
     "dev": "webpack --mode development --target node && webpack --mode development --target web",
-    "build": "npm run build:prod",
+    "build": "npm run build:prod && npm run build:types",
     "build:prod": "npm run build:prod:node && npm run build:prod:web",
     "build:prod:node": "webpack --mode production --target node",
-    "build:prod:web": "webpack --mode production --target web"
+    "build:prod:web": "webpack --mode production --target web",
+    "build:types": "cp src/georaster.d.ts dist/georaster.d.ts"
   },
   "repository": {
     "type": "git",

src/georaster.d.ts

@@ -0,0 +1,83 @@
+declare function parseGeoraster(
+  data: object | string | Buffer | ArrayBuffer | number[][][],
+  /** the raster metadata */
+  metadata?: parseGeoraster.GeorasterMetadata,
+  /** whether or not to print debug statements */
+  debug?: boolean
+): Promise<parseGeoraster.Georaster>;
+
+// Match default CJS export in index.js
+export = parseGeoraster;
+
+// A namespace with the same name as the default export is needed to define additional type exports
+// https://stackoverflow.com/a/51238234/4159809
+declare namespace parseGeoraster {
+  /** defines the new raster image to generate as a window in the source raster image.  Resolution (cell size) is determined from this */
+  export interface WindowOptions {
+    /** left side of the image window in pixel coordinates */
+    left: number
+    /** top of the image window in pixel coordinates */
+    top: number
+    /** right of the image window in pixel coordinates.  Should be greater than left */
+    right: number
+    /** bottom of the image window in pixel coordinates.  Should be greater than top */
+    bottom: number
+    /** width in pixels to make the resulting raster.  Will resample and/or use overview if not same as right - left */
+    width: number
+    /** height in pixels to make the resulting raster.  Will resample and/or use overview if not same as bottom - top */
+    height: number
+    /** method to map src raster values to result raster. Supports 'nearest' neighbor, defaults to 'bilinear' */
+    resampleMethod?: string
+  }
+
+  export interface Georaster {
+    /** raster values.  first dimension is raster band, remainder is 2D array of cell values */
+    values: number[][][];
+    /** raster height in units of projection */
+    height: number;
+    /** raster width in units of projection */
+    width: number;
+    /** raster height in pixels */
+    pixelHeight: number;
+    /** raster width in pixels */
+    pixelWidth: number;
+    /** Projection identifier */
+    projection: number;
+    /** left boundary, in units of projection*/
+    xmin: number;
+    /** right boundary, in units of projection */
+    xmax: number;
+    /** bottom boundary, in units of projection */
+    ymin: number;
+    /** top boundary, in units of projection */
+    ymax: number;
+    /** cell value representing "no data" in raster */
+    noDataValue: number;
+    /** number of raster bands */
+    numberOfRasters: number;
+    /** Minimum cell value for each raster band.  Indexed by band number */
+    mins: number[];
+    /** Maximum cell value for each raster band.  Indexed by band number */
+    maxs: number[];
+    /** difference between max and min for each raster band.  Indexed by band number */
+    ranges: number[];
+    /** if raster initialized with a URL, this method is available to fetch a
+     * specific subset or 'window' without reading the entire raster into memory.
+     * If the window options do not align exactly with the source image then a new
+     * one is generated using the resampleMethod.  The best available overview will
+     * also be used if they are available. */
+    getValues?: (options: WindowOptions) => Promise<number[][][]>;
+    /** experimental! returns a canvas picture of the data. */
+    toCanvas: (options: { height?: number; width?: number }) => ImageData
+  }
+
+  export type GeorasterMetadata = Pick<
+    Georaster,
+    | "noDataValue"
+    | "projection"
+    | "xmin"
+    | "ymax"
+    | "pixelWidth"
+    | "pixelHeight"
+  >;
+}