Merge to XFA: Separate agg-authored code from fx-authored code.

Original Review URL: https://codereview.chromium.org/1152743007.
BUG=pdfium:166
R=brucedawson@chromium.org, thestig@chromium.org
TBR=brucedawson@chromium.org, thestig@chromium.org

Review URL: https://codereview.chromium.org/1186423003.

1 files changed, 63 insertions, 0 deletions

diff --git a/third_party/agg23/agg_math.h b/third_party/agg23/agg_math.h
new file mode 100644
index 0000000000..31e0daf3bb
--- /dev/null
+++ b/third_party/agg23/agg_math.h
@@ -0,0 +1,63 @@
+
+//----------------------------------------------------------------------------
+// Anti-Grain Geometry - Version 2.3
+// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
+//
+// Permission to copy, use, modify, sell and distribute this software
+// is granted provided this copyright notice appears in all copies.
+// This software is provided "as is" without express or implied
+// warranty, and with no claim as to its suitability for any purpose.
+//
+//----------------------------------------------------------------------------
+// Contact: mcseem@antigrain.com
+//          mcseemagg@yahoo.com
+//          http://www.antigrain.com
+//----------------------------------------------------------------------------
+// Bessel function (besj) was adapted for use in AGG library by Andy Wilk
+// Contact: castor.vulgaris@gmail.com
+//----------------------------------------------------------------------------
+#ifndef AGG_MATH_INCLUDED
+#define AGG_MATH_INCLUDED
+#include "agg_basics.h"
+namespace agg
+{
+const FX_FLOAT intersection_epsilon = 1.0e-30f;
+AGG_INLINE FX_FLOAT calc_point_location(FX_FLOAT x1, FX_FLOAT y1,
+                                        FX_FLOAT x2, FX_FLOAT y2,
+                                        FX_FLOAT x,  FX_FLOAT y)
+{
+    return FXSYS_Mul(x - x2, y2 - y1) - FXSYS_Mul(y - y2, x2 - x1);
+}
+AGG_INLINE FX_FLOAT calc_distance(FX_FLOAT x1, FX_FLOAT y1, FX_FLOAT x2, FX_FLOAT y2)
+{
+    FX_FLOAT dx = x2 - x1;
+    FX_FLOAT dy = y2 - y1;
+    return FXSYS_sqrt2(dx, dy);
+}
+AGG_INLINE FX_FLOAT calc_line_point_distance(FX_FLOAT x1, FX_FLOAT y1,
+        FX_FLOAT x2, FX_FLOAT y2,
+        FX_FLOAT x,  FX_FLOAT y)
+{
+    FX_FLOAT dx = x2 - x1;
+    FX_FLOAT dy = y2 - y1;
+    FX_FLOAT d = FXSYS_sqrt2(dx, dy);
+    if(d < intersection_epsilon) {
+        return calc_distance(x1, y1, x, y);
+    }
+    return FXSYS_MulDiv(x - x2, dy, d) - FXSYS_MulDiv(y - y2, dx, d);
+}
+AGG_INLINE bool calc_intersection(FX_FLOAT ax, FX_FLOAT ay, FX_FLOAT bx, FX_FLOAT by,
+                                  FX_FLOAT cx, FX_FLOAT cy, FX_FLOAT dx, FX_FLOAT dy,
+                                  FX_FLOAT* x, FX_FLOAT* y)
+{
+    FX_FLOAT num = FXSYS_Mul(ay - cy, dx - cx) - FXSYS_Mul(ax - cx, dy - cy);
+    FX_FLOAT den = FXSYS_Mul(bx - ax, dy - cy) - FXSYS_Mul(by - ay, dx - cx);
+    if (FXSYS_fabs(den) < intersection_epsilon) {
+        return false;
+    }
+    *x = ax + FXSYS_MulDiv(bx - ax, num, den);
+    *y = ay + FXSYS_MulDiv(by - ay, num, den);
+    return true;
+}
+}
+#endif