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[base] Clean up BBox_Conic_Check.

* src/base/ftbbox.c (BBox_Conic_Check): Remove redundant checks for
extremum at the segment ends, which are already within the bbox.
Slightly modify calculations.

git/fs: mount .git/fs: mount/attach disallowed

--- a/ChangeLog

+++ b/ChangeLog

@@ -1,3 +1,11 @@

+2013-08-17  Alexei Podtelezhnikov  <[email protected]>

+

+	[base] Clean up BBox_Conic_Check.

+

+	* src/base/ftbbox.c (BBox_Conic_Check): Remove redundant checks for

+	extremum at the segment ends, which are already within the bbox.

+	Slightly modify calculations. 

+

 2013-08-15  Alexei Podtelezhnikov  <[email protected]>

 	[base] Finish experimental (disabled) BBox_Cubic_Check implementation.

--- a/src/base/ftbbox.c

+++ b/src/base/ftbbox.c

@@ -108,30 +108,19 @@

                     FT_Pos*  min,

                     FT_Pos*  max )

   {

-    if ( y1 <= y3 && y2 == y1 )     /* flat arc */

-      goto Suite;

+    /* This function is only called when a control off-point is outside  */

+    /* the bbox. This also means there must be a local extremum within   */

+    /* the segment with the value of (y1*y3 - y2*y2)/(y1 - 2*y2 + y3).   */

+    /* Offsetting from the closest point to the extermum, y2, we get     */

-    if ( y1 < y3 )

-    {

-      if ( y2 >= y1 && y2 <= y3 )   /* ascending arc */

-        goto Suite;

-    }

-    else

-    {

-      if ( y2 >= y3 && y2 <= y1 )   /* descending arc */

-      {

-        y2 = y1;

-        y1 = y3;

-        y3 = y2;

-        goto Suite;

-      }

-    }

+    y1 -= y2;

+    y3 -= y2;

+    y2 += FT_MulDiv( y1, y3, y1 + y3 );

-    y1 = y3 = y1 - FT_MulDiv( y2 - y1, y2 - y1, y1 - 2*y2 + y3 );

-

-  Suite:

-    if ( y1 < *min ) *min = y1;

-    if ( y3 > *max ) *max = y3;

+    if ( y2 < *min )

+      *min = y2;

+    if ( y2 > *max )

+      *max = y2;

   }