[cairo-commit] 2 commits - src/cairo-spline.c

[Behdad Esfahbod]

 src/cairo-spline.c |   13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

New commits:
commit 0b59e29004bb19eb9bd458bbe6a48a7c367f72d0
Author: Behdad Esfahbod <behdad at behdad.org>
Date:   Sun Dec 28 02:49:39 2008 -0500

    [_cairo_spline_bound] Simplify condition

diff --git a/src/cairo-spline.c b/src/cairo-spline.c
index d2c45c3..f9b1aaf 100644
--- a/src/cairo-spline.c
+++ b/src/cairo-spline.c
@@ -277,18 +277,22 @@ _cairo_spline_bound (cairo_spline_add_point_func_t add_point_func,
 	    double b2 = b * b; \
 	    double delta = b2 - a * c; \
 	    if (delta > 0) { \
-		double a2_b2 = a * a + b2; \
+		cairo_bool_t feasible; \
 		double _2ab = 2 * a * b; \
-	        double _b_a = - b / a; \
 		/* We are only interested in solutions t that satisfy 0<t<1 \
 		 * here.  We do some checks to avoid sqrt if the solutions \
 		 * are not in that range.  The checks can be derived from: \
 		 * \
 		 *   0 < (-b±√delta)/a < 1 \
 		 */ \
-		if ((_2ab >= 0 && delta > b2 && delta < a2_b2 - _2ab) || \
-		    (_2ab <  0 && ((_b_a>=1 && (delta < b2 && delta > a2_b2 + _2ab)) || \
-		                   (_b_a< 1 && (delta < b2 || delta < a2_b2 + _2ab))))) { \
+		if (_2ab >= 0) \
+		    feasible = delta > b2 && delta < a*a + b2 - _2ab; \
+		else if (-b / a >= 1) \
+		    feasible = delta < b2 && delta > a*a + b2 + _2ab; \
+		else \
+		    feasible = delta < b2 || delta < a*a + b2 + _2ab; \
+	        \
+		if (unlikely (feasible)) { \
 		    double sqrt_delta = sqrt (delta); \
 		    ADD ((-b - sqrt_delta) / a); \
 		    ADD ((-b + sqrt_delta) / a); \
commit 3bf1b7d574620b1ab3c1fa50977a23d36ab04a40
Author: Behdad Esfahbod <behdad at behdad.org>
Date:   Sun Dec 28 02:41:39 2008 -0500

    [_cairo_spline_bound] Fix the check for feasible solutions
    
    Also make it more strict.  The only times we call sqrt now is
    when a solution in (0,1) exists.

diff --git a/src/cairo-spline.c b/src/cairo-spline.c
index 5f2dc6c..d2c45c3 100644
--- a/src/cairo-spline.c
+++ b/src/cairo-spline.c
@@ -277,15 +277,18 @@ _cairo_spline_bound (cairo_spline_add_point_func_t add_point_func,
 	    double b2 = b * b; \
 	    double delta = b2 - a * c; \
 	    if (delta > 0) { \
-		double a2 = a * a; \
-		double ab = a * b; \
+		double a2_b2 = a * a + b2; \
+		double _2ab = 2 * a * b; \
+	        double _b_a = - b / a; \
 		/* We are only interested in solutions t that satisfy 0<t<1 \
 		 * here.  We do some checks to avoid sqrt if the solutions \
 		 * are not in that range.  The checks can be derived from: \
 		 * \
 		 *   0 < (-b±√delta)/a < 1 \
 		 */ \
-		if (delta > (ab >= 0 ? b2 : a2 + b2 + 2*ab)) { \
+		if ((_2ab >= 0 && delta > b2 && delta < a2_b2 - _2ab) || \
+		    (_2ab <  0 && ((_b_a>=1 && (delta < b2 && delta > a2_b2 + _2ab)) || \
+		                   (_b_a< 1 && (delta < b2 || delta < a2_b2 + _2ab))))) { \
 		    double sqrt_delta = sqrt (delta); \
 		    ADD ((-b - sqrt_delta) / a); \
 		    ADD ((-b + sqrt_delta) / a); \