Constraint objects moved to ol namespace from ol.interaction namespace

src/ol/resolutionconstraint.js

@@ -0,0 +1,73 @@
+goog.provide('ol.ResolutionConstraint');
+goog.provide('ol.ResolutionConstraintType');
+
+goog.require('goog.math');
+goog.require('ol.array');
+
+
+/**
+ * @typedef {function((number|undefined), number): (number|undefined)}
+ */
+ol.ResolutionConstraintType;
+
+
+/**
+ * @param {number} power Power.
+ * @param {number} maxResolution Maximum resolution.
+ * @param {number=} opt_minResolution Minimum resolution.
+ * @return {ol.ResolutionConstraintType} Zoom function.
+ */
+ol.ResolutionConstraint.createContinuous =
+    function(power, maxResolution, opt_minResolution) {
+  var minResolution = opt_minResolution || 0;
+  return function(resolution, delta) {
+    if (goog.isDef(resolution)) {
+      resolution /= Math.pow(power, delta);
+      return goog.math.clamp(resolution, minResolution, maxResolution);
+    } else {
+      return undefined;
+    }
+  };
+};
+
+
+/**
+ * @param {Array.<number>} resolutions Resolutions.
+ * @return {ol.ResolutionConstraintType} Zoom function.
+ */
+ol.ResolutionConstraint.createSnapToResolutions =
+    function(resolutions) {
+  return function(resolution, delta) {
+    if (goog.isDef(resolution)) {
+      var z = ol.array.linearFindNearest(resolutions, resolution);
+      z = goog.math.clamp(z + delta, 0, resolutions.length - 1);
+      return resolutions[z];
+    } else {
+      return undefined;
+    }
+  };
+};
+
+
+/**
+ * @param {number} power Power.
+ * @param {number} maxResolution Maximum resolution.
+ * @param {number=} opt_maxLevel Maximum level.
+ * @return {ol.ResolutionConstraintType} Zoom function.
+ */
+ol.ResolutionConstraint.createSnapToPower =
+    function(power, maxResolution, opt_maxLevel) {
+  return function(resolution, delta) {
+    if (goog.isDef(resolution)) {
+      var oldLevel = Math.floor(
+          Math.log(maxResolution / resolution) / Math.log(power) + 0.5);
+      var newLevel = Math.max(oldLevel + delta, 0);
+      if (goog.isDef(opt_maxLevel)) {
+        newLevel = Math.min(newLevel, opt_maxLevel);
+      }
+      return maxResolution / Math.pow(power, newLevel);
+    } else {
+      return undefined;
+    }
+  };
+};