Math Lib: add shell_v3v3_normalized_to_dist and v2 version

bypass angle calculation to avoids (asin, sqrt, cos).

4 files changed, 38 insertions, 14 deletions

diff --git a/source/blender/blenlib/BLI_math_base.h b/source/blender/blenlib/BLI_math_base.h
index 68ffb4b4893..5bd8490db6e 100644
--- a/source/blender/blenlib/BLI_math_base.h
+++ b/source/blender/blenlib/BLI_math_base.h
@@ -241,8 +241,6 @@ MINLINE int mod_i(int i, int n);
 MINLINE unsigned int highest_order_bit_i(unsigned int n);
 MINLINE unsigned short highest_order_bit_s(unsigned short n);
 
-MINLINE float shell_angle_to_dist(const float angle);
-
 #if defined(_MSC_VER) && (_MSC_VER < 1800)
 extern double copysign(double x, double y);
 extern double round(double x);
diff --git a/source/blender/blenlib/BLI_math_geom.h b/source/blender/blenlib/BLI_math_geom.h
index 6ba8910db14..5067cee7352 100644
--- a/source/blender/blenlib/BLI_math_geom.h
+++ b/source/blender/blenlib/BLI_math_geom.h
@@ -314,6 +314,10 @@ MINLINE int min_axis_v3(const float vec[3]);
 
 MINLINE int poly_to_tri_count(const int poly_count, const int corner_count);
 
+MINLINE float shell_angle_to_dist(const float angle);
+MINLINE float shell_v3v3_normalized_to_dist(const float a[3], const float b[3]);
+MINLINE float shell_v2v2_normalized_to_dist(const float a[2], const float b[2]);
+
 /**************************** Inline Definitions ******************************/
 
 #if BLI_MATH_DO_INLINE
diff --git a/source/blender/blenlib/intern/math_base_inline.c b/source/blender/blenlib/intern/math_base_inline.c
index 82c6e68ccc2..e6217329145 100644
--- a/source/blender/blenlib/intern/math_base_inline.c
+++ b/source/blender/blenlib/intern/math_base_inline.c
@@ -44,9 +44,6 @@
 #  define UNLIKELY(x)     (x)
 #endif
 
-/* A few small defines. Keep'em local! */
-#define SMALL_NUMBER  1.e-8f
-
 MINLINE float sqrt3f(float f)
 {
 	if      (UNLIKELY(f == 0.0f)) return 0.0f;
@@ -111,15 +108,6 @@ MINLINE float interpf(float target, float origin, float fac)
 	return (fac * target) + (1.0f - fac) * origin;
 }
 
-/* useful to calculate an even width shell, by taking the angle between 2 planes.
- * The return value is a scale on the offset.
- * no angle between planes is 1.0, as the angle between the 2 planes approaches 180d
- * the distance gets very high, 180d would be inf, but this case isn't valid */
-MINLINE float shell_angle_to_dist(const float angle)
-{
-	return (UNLIKELY(angle < SMALL_NUMBER)) ? 1.0f : fabsf(1.0f / cosf(angle));
-}
-
 /* used for zoom values*/
 MINLINE float power_of_2(float val)
 {
diff --git a/source/blender/blenlib/intern/math_geom_inline.c b/source/blender/blenlib/intern/math_geom_inline.c
index 0e243c5e198..1e54dd11a76 100644
--- a/source/blender/blenlib/intern/math_geom_inline.c
+++ b/source/blender/blenlib/intern/math_geom_inline.c
@@ -34,6 +34,9 @@
 
 #include <string.h>
 
+/* A few small defines. Keep'em local! */
+#define SMALL_NUMBER  1.e-8f
+
 /********************************** Polygons *********************************/
 
 MINLINE float cross_tri_v2(const float v1[2], const float v2[2], const float v3[2])
@@ -227,4 +230,35 @@ MINLINE float plane_point_side_v3(const float plane[4], const float co[3])
 	return dot_v3v3(co, plane) + plane[3];
 }
 
+/* useful to calculate an even width shell, by taking the angle between 2 planes.
+ * The return value is a scale on the offset.
+ * no angle between planes is 1.0, as the angle between the 2 planes approaches 180d
+ * the distance gets very high, 180d would be inf, but this case isn't valid */
+MINLINE float shell_angle_to_dist(const float angle)
+{
+	return (UNLIKELY(angle < SMALL_NUMBER)) ? 1.0f : fabsf(1.0f / cosf(angle));
+}
+/**
+ * equivalent to ``shell_angle_to_dist(angle_normalized_v3v3(a, b))``
+ */
+MINLINE float shell_v3v3_normalized_to_dist(const float a[3], const float b[3])
+{
+	const float angle_cos = fabsf(dot_v3v3(a, b));
+	BLI_ASSERT_UNIT_V3(a);
+	BLI_ASSERT_UNIT_V3(b);
+	return (UNLIKELY(angle_cos < SMALL_NUMBER)) ? 1.0f : (1.0f / angle_cos);
+}
+/**
+ * equivalent to ``shell_angle_to_dist(angle_normalized_v2v2(a, b))``
+ */
+MINLINE float shell_v2v2_normalized_to_dist(const float a[2], const float b[2])
+{
+	const float angle_cos = fabsf(dot_v2v2(a, b));
+	BLI_ASSERT_UNIT_V2(a);
+	BLI_ASSERT_UNIT_V2(b);
+	return (UNLIKELY(angle_cos < SMALL_NUMBER)) ? 1.0f : (1.0f / angle_cos);
+}
+
+#undef SMALL_NUMBER
+
 #endif /* __MATH_GEOM_INLINE_C__ */