Rift.IO OSM R1 Initial Submission

[osm/UI.git] / skyquake / plugins / composer / src / src / libraries / zoomFactor.js

diff --git a/skyquake/plugins/composer/src/src/libraries/zoomFactor.js b/skyquake/plugins/composer/src/src/libraries/zoomFactor.js
new file mode 100644 (file)
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+++ b/skyquake/plugins/composer/src/src/libraries/zoomFactor.js
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+
+/*
+ * 
+ *   Copyright 2016 RIFT.IO Inc
+ *
+ *   Licensed under the Apache License, Version 2.0 (the "License");
+ *   you may not use this file except in compliance with the License.
+ *   You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *   Unless required by applicable law or agreed to in writing, software
+ *   distributed under the License is distributed on an "AS IS" BASIS,
+ *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *   See the License for the specific language governing permissions and
+ *   limitations under the License.
+ *
+ */
+'use strict';
+export default function zoomFactor(element = document.body) {
+       let factor;
+       const rect = element.getBoundingClientRect();
+       const physicalW = rect.right - rect.left;
+       const logicalW = element.offsetWidth;
+       factor = Math.round((physicalW / logicalW) * 100) / 100;
+       // if fullscreen mode offsetWidth is 0
+       if (isNaN(factor)) {
+               factor = 1;
+       }
+       return factor;
+}