Add and use new proj4.register function

src/ol/proj.js

@@ -8,7 +8,6 @@ import EPSG3857 from './proj/EPSG3857.js';
 import EPSG4326 from './proj/EPSG4326.js';
 import Projection from './proj/Projection.js';
 import Units from './proj/Units.js';
-import _ol_proj_proj4_ from './proj/proj4.js';
 import _ol_proj_projections_ from './proj/projections.js';
 import {add as addTransformFunc, clear as clearTransformFuncs, get as getTransformFunc} from './proj/transforms.js';
 
@@ -29,23 +28,6 @@ export var METERS_PER_UNIT = Units.METERS_PER_UNIT;
 var SPHERE = new Sphere(Sphere.DEFAULT_RADIUS);
 
 
-/**
- * Register proj4. If not explicitly registered, it will be assumed that
- * proj4js will be loaded in the global namespace. For example in a
- * browserify ES6 environment you could use:
- *
- *     import ol from 'openlayers';
- *     import proj4 from 'proj4';
- *     ol.proj.setProj4(proj4);
- *
- * @param {Proj4} proj4 Proj4.
- * @api
- */
-export function setProj4(proj4) {
-  _ol_proj_proj4_.set(proj4);
-}
-
-
 /**
  * @param {Array.<number>} input Input coordinate array.
  * @param {Array.<number>=} opt_output Output array of coordinate values.
@@ -121,13 +103,6 @@ export function get(projectionLike) {
   } else if (typeof projectionLike === 'string') {
     var code = projectionLike;
     projection = _ol_proj_projections_.get(code);
-    if (!projection) {
-      var proj4js = _ol_proj_proj4_.get();
-      if (typeof proj4js == 'function' && proj4js.defs(code) !== undefined) {
-        projection = new Projection({code: code});
-        addProjection(projection);
-      }
-    }
   }
   return projection;
 }
@@ -390,24 +365,6 @@ export function equivalent(projection1, projection2) {
 export function getTransformFromProjections(sourceProjection, destinationProjection) {
   var sourceCode = sourceProjection.getCode();
   var destinationCode = destinationProjection.getCode();
-  if (!transformFunc) {
-    var proj4js = _ol_proj_proj4_.get();
-    if (typeof proj4js == 'function') {
-      var sourceDef = proj4js.defs(sourceCode);
-      var destinationDef = proj4js.defs(destinationCode);
-
-      if (sourceDef !== undefined && destinationDef !== undefined) {
-        if (sourceDef === destinationDef) {
-          addEquivalentProjections([destinationProjection, sourceProjection]);
-        } else {
-          var proj4Transform = proj4js(destinationCode, sourceCode);
-          addCoordinateTransforms(destinationProjection, sourceProjection,
-              proj4Transform.forward, proj4Transform.inverse);
-        }
-        transformFunc = _ol_proj_transforms_.get(sourceCode, destinationCode);
-      }
-    }
-  }
   var transformFunc = getTransformFunc(sourceCode, destinationCode);
   if (!transformFunc) {
     transformFunc = identityTransform;

src/ol/proj/Projection.js

@@ -2,7 +2,6 @@
  * @module ol/proj/Projection
  */
 import _ol_proj_Units_ from '../proj/Units.js';
-import _ol_proj_proj4_ from '../proj/proj4.js';
 
 /**
  * @classdesc
@@ -105,23 +104,6 @@ var _ol_proj_Projection_ = function(options) {
    * @type {number|undefined}
    */
   this.metersPerUnit_ = options.metersPerUnit;
-
-  var code = options.code;
-  var proj4js = _ol_proj_proj4_.get();
-  if (typeof proj4js == 'function') {
-    var def = proj4js.defs(code);
-    if (def !== undefined) {
-      if (def.axis !== undefined && options.axisOrientation === undefined) {
-        this.axisOrientation_ = def.axis;
-      }
-      if (options.metersPerUnit === undefined) {
-        this.metersPerUnit_ = def.to_meter;
-      }
-      if (options.units === undefined) {
-        this.units_ = def.units;
-      }
-    }
-  }
 };
 
 

src/ol/proj/index.jsdoc

@@ -21,15 +21,14 @@
  * for the required projections. These definitions can be obtained from
  * {@link https://epsg.io/}, and are a JS function, so can be loaded in a script
  * tag (as in the examples) or pasted into your application.
- * The first time there is a request for a projection, either with a
- * {@link ol.proj.projectionLike} or directly with {@link ol.proj.get}, the
- * code will check if the Proj4js library and the necessary definition are
- * loaded; if so, it will register the appropriate {@link ol.proj.Projection}
- * object and add transform functions between the new projection and all the
- * existing ones. See examples/wms-image-custom-proj for an example of this.
- * Because the check for presence of the Proj4js library and the definition only
- * takes place on the first request for them, this means they can be loaded
- * dynamically as needed; for example, with user-supplied data where you don't
+ *
+ * After all required projection definitions are added to proj4's registry (by
+ * using `proj4.defs()`), simply call `register(proj4)` from the `ol/proj/proj4`
+ * package. Existing transforms are not changed by this function. See
+ * examples/wms-image-custom-proj for an example of this.
+ *
+ * Additional projection definitions can be registered with `proj4.defs()` any
+ * time. Just make sure to call `register(proj4)` again; for example, with user-supplied data where you don't
  * know in advance what projections are needed, you can initially load minimal
  * support and then load whichever are requested.
  *

src/ol/proj/proj4.js

@@ -1,30 +1,51 @@
 /**
  * @module ol/proj/proj4
  */
-var _ol_proj_proj4_ = {};
-
+import {addCoordinateTransforms, addProjection, addEquivalentProjections, get} from '../proj.js';
+import {get as getTransform} from './transforms.js';
+import Projection from './Projection.js';
 
 /**
- * @private
- * @type {Proj4}
+ * Make projections defined in proj4 (with `proj4.defs()`) available in
+ * OpenLayers.
+ *
+ * This function should be called whenever changes are made to the proj4
+ * registry, e.g. after calling `proj4.defs()`. Existing transforms will not be
+ * modified by this function.
+ *
+ * @param {?} proj4 Proj4.
+ * @api
  */
-_ol_proj_proj4_.cache_ = null;
-
-
-/**
- * Store the proj4 function.
- * @param {Proj4} proj4 The proj4 function.
- */
-_ol_proj_proj4_.set = function(proj4) {
-  _ol_proj_proj4_.cache_ = proj4;
-};
-
-
-/**
- * Get proj4.
- * @return {Proj4} The proj4 function set above or available globally.
- */
-_ol_proj_proj4_.get = function() {
-  return _ol_proj_proj4_.cache_ || window['proj4'];
-};
-export default _ol_proj_proj4_;
+export function register(proj4) {
+  var projCodes = Object.keys(proj4.defs);
+  var len = projCodes.length;
+  var i, j;
+  for (i = 0; i < len; ++i) {
+    var code = projCodes[i];
+    if (!get(code)) {
+      var def = proj4.defs(code);
+      addProjection(new Projection({
+        code: code,
+        axisOrientation: def.axis,
+        metersPerUnit: def.to_meter,
+        units: def.units
+      }));
+    }
+  }
+  for (i = 0; i < len; ++i) {
+    var code1 = projCodes[i];
+    var proj1 = get(code1);
+    for (j = 0; j < len; ++j) {
+      var code2 = projCodes[j];
+      var proj2 = get(code2);
+      if (!getTransform(code1, code2)) {
+        if (proj4.defs[code1] === proj4.defs[code2]) {
+          addEquivalentProjections([proj1, proj2]);
+        } else {
+          var transform = proj4(code1, code2);
+          addCoordinateTransforms(proj1, proj2, transform.forward, transform.inverse);
+        }
+      }
+    }
+  }
+}