initial commit

js/geo-bounds.js

@@ -0,0 +1,141 @@
+"use strict";
+
+var gs_base_bounds = {
+    copyright:"stewart allen <stewart@neuron.com> -- all rights reserved"
+};
+
+(function() {
+
+    if (!self.base) self.base = {};
+    if (self.base.Bounds) return;
+
+    /**
+     *
+     * @constructor
+     */
+    function Bounds() {
+        this.minx = 10e7;
+        this.miny = 10e7;
+        this.maxx = -10e7;
+        this.maxy = -10e7;
+        this.leftMost = null;
+    }
+
+    var BASE = self.base,
+        UTIL = BASE.util,
+        CONF = BASE.config,
+        ABS = Math.abs,
+        MIN = Math.min,
+        MAX = Math.max,
+        BoP = Bounds.prototype;
+
+    BASE.Bounds = Bounds;
+    BASE.newBounds = newBounds;
+
+    /** ******************************************************************
+     * Bounds Prototype Functions
+     ******************************************************************* */
+
+    /**
+     * @returns {Bounds}
+     */
+    BoP.clone = function() {
+        var b = new Bounds();
+        b.minx = this.minx;
+        b.miny = this.miny;
+        b.maxx = this.maxx;
+        b.maxy = this.maxy;
+        return b;
+    };
+
+    BoP.equals = function(bounds, margin) {
+        if (!margin) margin = BASE.config.precision_offset;
+        return UTIL.isCloseTo(this.minx, bounds.minx, margin) &&
+            UTIL.isCloseTo(this.miny, bounds.miny, margin) &&
+            UTIL.isCloseTo(this.maxx, bounds.maxx, margin) &&
+            UTIL.isCloseTo(this.maxy, bounds.maxy, margin);
+    };
+
+    /**
+     * @param {Bounds} b
+     */
+    BoP.merge = function(b) {
+        this.minx = MIN(this.minx, b.minx);
+        this.maxx = MAX(this.maxx, b.maxx);
+        this.miny = MIN(this.miny, b.miny);
+        this.maxy = MAX(this.maxy, b.maxy);
+    };
+
+    /**
+     * @param {Point} p
+     */
+    BoP.update = function(p) {
+        this.minx = MIN(this.minx, p.x);
+        this.maxx = MAX(this.maxx, p.x);
+        this.miny = MIN(this.miny, p.y);
+        this.maxy = MAX(this.maxy, p.y);
+        if (this.minx === p.x) this.leftMost = p;
+    };
+
+    BoP.contains = function(bounds) {
+        return bounds.isNested(this);
+    };
+
+    BoP.containsXY = function(x,y) {
+        return x >= this.minx && x <= this.maxx && y >= this.miny && y <= this.maxy;
+    };
+
+    BoP.containsOffsetXY = function(x,y,offset) {
+        return x >= this.minx-offset && x <= this.maxx+offset && y >= this.miny-offset && y <= this.maxy+offset;
+    };
+
+    /**
+     * @param {Bounds} parent
+     * @returns {boolean} true if fully inside parent bounds
+     */
+    BoP.isNested = function(parent) {
+        return (
+            this.minx >= parent.minx - CONF.precision_bounds && // min-x
+            this.maxx <= parent.maxx + CONF.precision_bounds && // max-x
+            this.miny >= parent.miny - CONF.precision_bounds && // min-y
+            this.maxy <= parent.maxy + CONF.precision_bounds    // max-y
+        );
+    };
+
+    /**
+     * @param {Bounds} b
+     * @param {number} precision
+     * @returns {boolean}
+     */
+    BoP.overlaps = function(b, precision) {
+        return (
+            ABS(this.centerx() - b.centerx()) * 2 - precision < this.width() + b.width() &&
+            ABS(this.centery() - b.centery()) * 2 - precision < this.height() + b.height()
+        );
+    };
+
+    BoP.width = function() {
+        return this.maxx - this.minx;
+    };
+
+    BoP.height = function() {
+        return this.maxy - this.miny;
+    };
+
+    BoP.centerx = function() {
+        return this.minx + this.width() / 2;
+    };
+
+    BoP.centery = function() {
+        return this.miny + this.height() / 2;
+    };
+
+    /** ******************************************************************
+     * Connect to base and Helpers
+     ******************************************************************* */
+
+    function newBounds() {
+        return new Bounds();
+    }
+
+})();