-- Fixed an issue with AABBs creating with a 'vec' argument having

negative values. Added 'touches' to test if two boxes touch but do not overlap.
Unit tests were added to reflect these changes.

Signed off by Mark Farrell <markfarr2011@gmail.com>

index.js

@@ -3,17 +3,20 @@ module.exports = AABB
 var vec3 = require('gl-matrix').vec3
 
 function AABB(pos, vec) {
+
   if(!(this instanceof AABB)) {
     return new AABB(pos, vec)
   }
 
-  this.base = pos
+  var pos2 = vec3.create()
+  vec3.add(pos2, pos, vec)
+
+  this.base = vec3.min(vec3.create(), pos, pos2)
   this.vec = vec
+  this.max = vec3.max(vec3.create(), pos, pos2)
 
   this.mag = vec3.length(this.vec)
 
-  this.max = vec3.create()
-  vec3.add(this.max, this.base, this.vec)
 }
 
 var cons = AABB
@@ -83,6 +86,17 @@ proto.intersects = function(aabb) {
   return true
 }
 
+proto.touches = function(aabb) {
+
+  var intersection = this.union(aabb);
+
+  return (intersection !== null) &&
+         ((intersection.width() == 0) ||
+         (intersection.height() == 0) || 
+         (intersection.depth() == 0))
+
+}
+
 proto.union = function(aabb) {
   if(!this.intersects(aabb)) return null
 
@@ -95,3 +109,7 @@ proto.union = function(aabb) {
 
   return new AABB([base_x, base_y, base_z], [max_x - base_x, max_y - base_y, max_z - base_z])
 }
+
+
+
+

test.js

@@ -91,5 +91,31 @@ test('intersects works', function(t) {
   b1 = aabb([12, 12, 12], [4, 4, 4])
   t.equals(b0.intersects(b1), true, 'should intersect (b0 contains b1)')
 
+  b1 = aabb([-5, -5, -5], [20, 20, 20])
+  t.equals(b0.intersects(b1), true, 'should intersects (b0 contains b1)')
+
+  b1 = aabb([-5, -5, -5], [10, 10, 10])
+  t.equals(b0.intersects(b1), false, 'should not intersect (b0 does not contain b1)')
+
   t.end()
 })
+
+test('touches works', function(t) { 
+  var b0 = aabb([10,10,10], [10, 10, 10])
+    , b1 = aabb([0, 0, 0], [10, 10, 10])
+
+  t.equals(b0.touches(b1), true, 'should touch')
+
+  b1 = aabb([10, 0, 0], [10, 10, 10])
+  t.equals(b0.touches(b1), true, 'should touch')
+
+  b1 = aabb([0, 10, 0], [10, 10, 10])
+  t.equals(b0.touches(b1), true, 'should touch')
+
+  b1 = aabb([0, 0, 10], [10, 10, 10])
+  t.equals(b0.touches(b1), true, 'should touch')
+
+  b1 = aabb([-10, -10, -10], [10, 10, 10])
+  t.equals(b0.touches(b1), false, 'should not touch')
+
+})