From eba3e95b81edf128a4af455aee34fbde61376188 Mon Sep 17 00:00:00 2001
From: Alexander Ljungberg <aljungberg@slevenbits.com>
Date: Mon, 15 Oct 2012 11:10:23 +0100
Subject: [PATCH] `CPBezierPath controlPointBounds` and `CGPathGetBoundingBox`.

---
 AppKit/CPBezierPath.j        |  13 +++++
 AppKit/CoreGraphics/CGPath.j | 102 +++++++++++++++++++++++++++++++++++
 2 files changed, 115 insertions(+)

diff --git a/AppKit/CPBezierPath.j b/AppKit/CPBezierPath.j
index de90822c4..213a61e96 100644
--- a/AppKit/CPBezierPath.j
+++ b/AppKit/CPBezierPath.j
@@ -165,6 +165,19 @@ var DefaultLineWidth = 1.0;
     CGPathAddCurveToPoint(_path, nil, controlPoint1.x, controlPoint1.y, controlPoint2.x, controlPoint2.y, endPoint.x, endPoint.y);
 }
 
+- (CGRect)bounds
+{
+    // TODO: this should return this. The controlPointBounds is not a tight fit.
+    // return CGPathGetPathBoundingBox(_path);
+
+    return [self controlPointBounds];
+}
+
+- (CGRect)controlPointBounds
+{
+    return CGPathGetBoundingBox(_path);
+}
+
 /*!
     Create a line segment between the first and last points in the subpath, closing it.
 */
diff --git a/AppKit/CoreGraphics/CGPath.j b/AppKit/CoreGraphics/CGPath.j
index 6d6a77301..9db475c66 100644
--- a/AppKit/CoreGraphics/CGPath.j
+++ b/AppKit/CoreGraphics/CGPath.j
@@ -406,6 +406,108 @@ function CGPathIsEmpty(aPath)
     return !aPath || aPath.count == 0;
 }
 
+/*!
+    Calculate the smallest rectangle to contain both the path of the receiver and all control points.
+*/
+function CGPathGetBoundingBox(aPath)
+{
+    if (!aPath || !aPath.count)
+        return _CGRectMakeZero();
+
+    var ox = 0,
+        oy = 0,
+        rx = 0,
+        ry = 0,
+        movePoint = nil;
+
+    function addPoint(x, y)
+    {
+        ox = MIN(ox, x);
+        oy = MIN(oy, y);
+        rx = MAX(rx, x);
+        ry = MAX(ry, y);
+    }
+
+    for (var i = 0, count = aPath.count; i < count; ++i)
+    {
+        var element = aPath.elements[i];
+
+        // Just enclose all the control points. The curves must be inside of the control points.
+        // This won't work for CGPathGetPathBoundingBox.
+        switch (element.type)
+        {
+            case kCGPathElementAddLineToPoint:
+                if (movePoint)
+                {
+                    addPoint(movePoint.x, movePoint.y);
+                    movePoint = nil;
+                }
+
+                addPoint(element.x, element.y);
+                break;
+
+            case kCGPathElementAddCurveToPoint:
+                if (movePoint)
+                {
+                    addPoint(movePoint.x, movePoint.y);
+                    movePoint = nil;
+                }
+
+                addPoint(element.cp1x, element.cp1y);
+                addPoint(element.cp2x, element.cp2y);
+                addPoint(element.x, element.y);
+                break;
+
+            case kCGPathElementAddArc:
+                if (movePoint)
+                {
+                    addPoint(movePoint.x, movePoint.y);
+                    movePoint = nil;
+                }
+
+                addPoint(element.x, element.y);
+                break;
+
+            case kCGPathElementAddArcToPoint:
+                if (movePoint)
+                {
+                    addPoint(movePoint.x, movePoint.y);
+                    movePoint = nil;
+                }
+
+                addPoint(element.p1x, element.p1y);
+                addPoint(element.p2x, element.p2y);
+                break;
+
+            case kCGPathElementAddQuadCurveToPoint:
+                if (movePoint)
+                {
+                    addPoint(movePoint.x, movePoint.y);
+                    movePoint = nil;
+                }
+
+                addPoint(element.cpx, element.cpy);
+                addPoint(element.x, element.y);
+                break;
+
+            case kCGPathElementMoveToPoint:
+                movePoint = _CGPointMake(element.x, element.y);
+                break;
+
+            case kCGPathElementCloseSubpath:
+                if (movePoint)
+                {
+                    addPoint(movePoint.x, movePoint.y);
+                    movePoint = nil;
+                }
+
+                break;
+        }
+    }
+
+    return _CGRectMake(ox, oy, rx - ox, ry - oy);
+}
+
 /*!
     @}
 */