From 0ac9e35f52cdb79d027481592a197d243d14dee6 Mon Sep 17 00:00:00 2001
From: Vladimir Agafonkin <agafonkin@gmail.com>
Date: Mon, 23 Jul 2018 12:43:58 +0300
Subject: [PATCH] dry up dem source, inherit xhr-avoiding logic

---
 src/source/raster_dem_tile_source.js | 51 ++++++++--------------------
 src/source/raster_tile_source.js     | 38 +++++++++++----------
 2 files changed, 35 insertions(+), 54 deletions(-)

diff --git a/src/source/raster_dem_tile_source.js b/src/source/raster_dem_tile_source.js
index 0cef8af2283..d808409f831 100644
--- a/src/source/raster_dem_tile_source.js
+++ b/src/source/raster_dem_tile_source.js
@@ -1,9 +1,7 @@
 // @flow
 
-import { getImage, ResourceType } from '../util/ajax';
 import { extend } from '../util/util';
 import { Evented } from '../util/evented';
-import { normalizeTileURL as normalizeURL } from '../util/mapbox';
 import browser from '../util/browser';
 import { OverscaledTileID } from './tile_id';
 import RasterTileSource from './raster_tile_source';
@@ -39,54 +37,33 @@ class RasterDEMTileSource extends RasterTileSource implements Source {
     }
 
     loadTile(tile: Tile, callback: Callback<void>) {
-        const url = normalizeURL(tile.tileID.canonical.url(this.tiles, this.scheme), this.url, this.tileSize);
-        tile.request = getImage(this.map._transformRequest(url, ResourceType.Tile), imageLoaded.bind(this));
-
         tile.neighboringTiles = this._getNeighboringTiles(tile.tileID);
-        function imageLoaded(err, img) {
-            delete tile.request;
-            if (tile.aborted) {
-                tile.state = 'unloaded';
-                callback(null);
-            } else if (err) {
-                tile.state = 'errored';
-                callback(err);
-            } else if (img) {
-                if (this.map._refreshExpiredTiles) tile.setExpiryData(img);
-                delete (img: any).cacheControl;
-                delete (img: any).expires;
-
-                const rawImageData = browser.getImageData(img);
-                const params = {
-                    uid: tile.uid,
-                    coord: tile.tileID,
-                    source: this.id,
-                    rawImageData: rawImageData,
-                    encoding: this.encoding
-                };
-
-                if (!tile.workerID || tile.state === 'expired') {
-                    tile.workerID = this.dispatcher.send('loadDEMTile', params, done.bind(this));
-                }
-            }
-        }
+        super.loadTile(tile, callback);
+    }
+
+    onTileLoad(tile: Tile, img: HTMLImageElement, callback: Callback<void>) {
+        if (tile.workerID && tile.state !== 'expired') return;
 
-        function done(err, dem) {
+        tile.workerID = this.dispatcher.send('loadDEMTile', {
+            uid: tile.uid,
+            coord: tile.tileID,
+            source: this.id,
+            rawImageData: browser.getImageData(img),
+            encoding: this.encoding
+        }, (err, dem) => {
             if (err) {
                 tile.state = 'errored';
                 callback(err);
-            }
 
-            if (dem) {
+            } else if (dem) {
                 tile.dem = dem;
                 tile.needsHillshadePrepare = true;
                 tile.state = 'loaded';
                 callback(null);
             }
-        }
+        });
     }
 
-
     _getNeighboringTiles(tileID: OverscaledTileID) {
         const canonical = tileID.canonical;
         const dim = Math.pow(2, canonical.z);
diff --git a/src/source/raster_tile_source.js b/src/source/raster_tile_source.js
index b0b43806825..78574483ce3 100644
--- a/src/source/raster_tile_source.js
+++ b/src/source/raster_tile_source.js
@@ -119,27 +119,31 @@ class RasterTileSource extends Evented implements Source {
                     this._avoidXHR = true;
                 }
 
-                const context = this.map.painter.context;
-                const gl = context.gl;
-                tile.texture = this.map.painter.getTileTexture(img.width);
-                if (tile.texture) {
-                    tile.texture.update(img, { useMipmap: true });
-                } else {
-                    tile.texture = new Texture(context, img, gl.RGBA, { useMipmap: true });
-                    tile.texture.bind(gl.LINEAR, gl.CLAMP_TO_EDGE, gl.LINEAR_MIPMAP_NEAREST);
-
-                    if (context.extTextureFilterAnisotropic) {
-                        gl.texParameterf(gl.TEXTURE_2D, context.extTextureFilterAnisotropic.TEXTURE_MAX_ANISOTROPY_EXT, context.extTextureFilterAnisotropicMax);
-                    }
-                }
-
-                tile.state = 'loaded';
-
-                callback(null);
+                this.onTileLoad(tile, img, callback);
             }
         }, this._avoidXHR);
     }
 
+    onTileLoad(tile: Tile, img: HTMLImageElement, callback: Callback<void>) {
+        const context = this.map.painter.context;
+        const gl = context.gl;
+        tile.texture = this.map.painter.getTileTexture(img.width);
+        if (tile.texture) {
+            tile.texture.update(img, { useMipmap: true });
+        } else {
+            tile.texture = new Texture(context, img, gl.RGBA, { useMipmap: true });
+            tile.texture.bind(gl.LINEAR, gl.CLAMP_TO_EDGE, gl.LINEAR_MIPMAP_NEAREST);
+
+            if (context.extTextureFilterAnisotropic) {
+                gl.texParameterf(gl.TEXTURE_2D, context.extTextureFilterAnisotropic.TEXTURE_MAX_ANISOTROPY_EXT, context.extTextureFilterAnisotropicMax);
+            }
+        }
+
+        tile.state = 'loaded';
+
+        callback(null);
+    }
+
     abortTile(tile: Tile, callback: Callback<void>) {
         if (tile.request) {
             tile.request.cancel();