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-rw-r--r--js/helper-classes/3D/math-utils.js97
1 files changed, 96 insertions, 1 deletions
diff --git a/js/helper-classes/3D/math-utils.js b/js/helper-classes/3D/math-utils.js
index 71ed62a0..58f0680a 100644
--- a/js/helper-classes/3D/math-utils.js
+++ b/js/helper-classes/3D/math-utils.js
@@ -8,7 +8,9 @@ No rights, expressed or implied, whatsoever to this software are provided by Mot
8// Class Utils 8// Class Utils
9// Math Utility functions 9// Math Utility functions
10/////////////////////////////////////////////////////////////////////// 10///////////////////////////////////////////////////////////////////////
11var VecUtils = require("js/helper-classes/3D/vec-utils").VecUtils; 11var VecUtils = require("js/helper-classes/3D/vec-utils").VecUtils,
12 ViewUtils = require("js/helper-classes/3D/view-utils").ViewUtils,
13 Rectangle = require("js/helper-classes/3D/rectangle").Rectangle;
12 14
13var MathUtilsClass = exports.MathUtilsClass = Object.create(Object.prototype, { 15var MathUtilsClass = exports.MathUtilsClass = Object.create(Object.prototype, {
14 /////////////////////////////////////////////////////////////////////// 16 ///////////////////////////////////////////////////////////////////////
@@ -536,6 +538,99 @@ var MathUtilsClass = exports.MathUtilsClass = Object.create(Object.prototype, {
536 } 538 }
537 }, 539 },
538 540
541 rectsOverlap:
542 {
543 value: function( pt, width, height, elt )
544 {
545 // only consider rectangles with non-zero area
546 if ((width == 0) || (height == 0)) return false;
547
548 // get the mins/maxs of the onput rectangle
549 var xMin, xMax, yMin, yMax;
550 if (width > 0) { xMin = pt[0]; xMax = pt[0] + width; }
551 else { xMax = pt[0]; xMin = pt[0] + width; }
552 if (height > 0) { yMin = pt[1]; yMax = pt[1] + height; }
553 else { yMax = pt[1]; yMin = pt[1] + height; }
554
555 // get the bounds of the element in global screen space
556 var bounds = ViewUtils.getElementViewBounds3D( elt );
557 var bounds3D = [];
558 for (var i=0; i<4; i++)
559 bounds3D[i] = ViewUtils.localToGlobal( bounds[i], elt );
560
561 // get the min/maxs for the element
562 var xMinElt = bounds3D[0][0], xMaxElt = bounds3D[0][0],
563 yMinElt = bounds3D[0][1], yMaxElt = bounds3D[0][1];
564 for (var i=1; i<4; i++)
565 {
566 if (bounds3D[i][0] < xMinElt) xMinElt = bounds3D[i][0];
567 else if (bounds3D[i][0] > xMaxElt) xMaxElt = bounds3D[i][0];
568 if (bounds3D[i][1] < yMinElt) yMinElt = bounds3D[i][1];
569 else if (bounds3D[i][1] > yMaxElt) yMaxElt = bounds3D[i][1];
570 }
571
572 // test 1. Overall bounding box test
573 if ((xMaxElt < xMin) || (xMinElt > xMax) || (yMaxElt < yMin) || (yMinElt > yMax))
574 return false;
575
576 // test 2. See if any of the corners of the element are contained in the rectangle
577 var rect = Object.create(Rectangle, {});
578 rect.set( pt[0], pt[1], width, height );
579 for (var i=0; i<4; i++)
580 {
581 if (rect.contains( bounds3D[i][0], bounds3D[i][1] )) return true;
582 }
583
584 // test 3. Bounding box tests on individual edges of the element
585 for (var i=0; i<4; i++)
586 {
587 var pt0 = bounds3D[i],
588 pt1 = bounds3D[(i+1)%4];
589
590 // get the extremes of the edge
591 if (pt0[0] < pt1[0]) { xMinElt = pt0[0]; xMaxElt = pt1[0]; }
592 else { xMaxElt = pt0[0]; xMinElt = pt1[0]; }
593 if (pt0[1] < pt1[1]) { yMinElt = pt0[1]; yMaxElt = pt1[1]; }
594 else { yMaxElt = pt0[1]; yMinElt = pt1[1]; }
595
596 if ((xMaxElt < xMin) || (xMinElt > xMax) || (yMaxElt < yMin) || (yMinElt > yMax))
597 continue;
598 else
599 {
600 // intersect the element edge with the 4 sides of the rectangle
601 // vertical edges
602 var xRect = xMin;
603 for (var j=0; j<2; j++)
604 {
605 if ((xMinElt < xRect) && (xMaxElt > xRect))
606 {
607 var t = (xRect - pt0[0])/(pt1[0] - pt0[0]);
608 var y = pt0[1] + t*(pt1[1] - pt0[1]);
609 if ((y >= yMin) && (y <= yMax)) return true;
610 }
611 xRect = xMax;
612 }
613
614 // horizontal edges
615 var yRect = yMin;
616 for (var j=0; j<2; j++)
617 {
618 if ((yMinElt < yRect) && (yMaxElt > yRect))
619 {
620 var t = (yRect - pt0[1])/(pt1[1] - pt0[1]);
621 var x = pt0[0] + t*(pt1[0] - pt0[0]);
622 if ((x >= xMin) && (x <= xMax)) return true;
623 }
624 yRect = yMax;
625 }
626 }
627 }
628
629 // if we get here there is no overlap
630 return false;
631 }
632 },
633
539 /////////////////////////////////////////////////////////////////////// 634 ///////////////////////////////////////////////////////////////////////
540 // Bezier Methods 635 // Bezier Methods
541 /////////////////////////////////////////////////////////////////////// 636 ///////////////////////////////////////////////////////////////////////