Old bug fix: Uv smart stitch failed to detect angle if islands were

rotated close to 180 degrees and there were edges both below and above
the 180 degree threshhold. Separating and averaging the negative and
positive angles seems to solve the issue making the tool a bit more
robust ;)

2 files changed, 15 insertions, 0 deletions

diff --git a/source/blender/blenlib/BLI_math_matrix.h b/source/blender/blenlib/BLI_math_matrix.h
index a5ab2373b89..97cd6a60862 100644
--- a/source/blender/blenlib/BLI_math_matrix.h
+++ b/source/blender/blenlib/BLI_math_matrix.h
@@ -88,6 +88,7 @@ void mul_serie_m4(float R[4][4],
 
 void mul_m4_v3(float M[4][4], float r[3]);
 void mul_v3_m4v3(float r[3], float M[4][4], const float v[3]);
+void mul_v2_m2v2(float r[2], float M[2][2], const float v[2]);
 void mul_mat3_m4_v3(float M[4][4], float r[3]);
 void mul_m4_v4(float M[4][4], float r[4]);
 void mul_v4_m4v4(float r[4], float M[4][4], const float v[4]);
@@ -170,6 +171,7 @@ void mat4_to_size(float r[3], float M[4][4]);
 
 void translate_m4(float mat[4][4], float tx, float ty, float tz);
 void rotate_m4(float mat[4][4], const char axis, const float angle);
+void rotate_m2(float mat[2][2], const float angle);
 
 
 void mat3_to_rot_size(float rot[3][3], float size[3], float mat3[3][3]);
diff --git a/source/blender/blenlib/intern/math_matrix.c b/source/blender/blenlib/intern/math_matrix.c
index 5c443b9b1f3..c12588463b0 100644
--- a/source/blender/blenlib/intern/math_matrix.c
+++ b/source/blender/blenlib/intern/math_matrix.c
@@ -344,6 +344,12 @@ void mul_v3_m4v3(float in[3], float mat[4][4], const float vec[3])
 	in[2] = x * mat[0][2] + y * mat[1][2] + mat[2][2] * vec[2] + mat[3][2];
 }
 
+void mul_v2_m2v2(float r[2], float M[2][2], const float v[2])
+{
+	r[0] = M[0][0]*v[0] + M[1][0]*v[1];
+	r[1] = M[0][1]*v[0] + M[1][1]*v[1];
+}
+
 /* same as mul_m4_v3() but doesnt apply translation component */
 void mul_mat3_m4_v3(float mat[4][4], float vec[3])
 {
@@ -1304,6 +1310,13 @@ void rotate_m4(float mat[4][4], const char axis, const float angle)
 	}
 }
 
+void rotate_m2(float mat[2][2], const float angle)
+{
+	mat[0][0] = mat[1][1] = cosf(angle);
+	mat[0][1] = sinf(angle);
+	mat[1][0] = -mat[0][1];
+}
+
 void blend_m3_m3m3(float out[3][3], float dst[3][3], float src[3][3], const float srcweight)
 {
 	float srot[3][3], drot[3][3];