bmesh: new wireframe tool

- makes wireframe from faces.
- options similar to inset (even offset, relative scale)
- copies face settings and loops (uvs, vcolors)
- optionally replaces the existing geometry.

2 files changed, 20 insertions, 0 deletions

diff --git a/source/blender/blenlib/BLI_math_vector.h b/source/blender/blenlib/BLI_math_vector.h
index af3df9c9ed2..df5199e19e7 100644
--- a/source/blender/blenlib/BLI_math_vector.h
+++ b/source/blender/blenlib/BLI_math_vector.h
@@ -186,6 +186,7 @@ float angle_normalized_v2v2(const float a[2], const float b[2]);
 float angle_v3v3(const float a[3], const float b[3]);
 float angle_v3v3v3(const float a[3], const float b[3], const float c[3]);
 float angle_normalized_v3v3(const float v1[3], const float v2[3]);
+float angle_on_axis_v3v3v3_v3(const float v1[3], const float v2[3], const float v3[3], const float axis[3]);
 void angle_tri_v3(float angles[3], const float v1[3], const float v2[3], const float v3[3]);
 void angle_quad_v3(float angles[4], const float v1[3], const float v2[3], const float v3[3], const float v4[3]);
 void angle_poly_v3(float* angles, const float* verts[3], int len);
diff --git a/source/blender/blenlib/intern/math_vector.c b/source/blender/blenlib/intern/math_vector.c
index f734e01943f..90e6a4cb945 100644
--- a/source/blender/blenlib/intern/math_vector.c
+++ b/source/blender/blenlib/intern/math_vector.c
@@ -217,6 +217,25 @@ float angle_normalized_v2v2(const float v1[2], const float v2[2])
 		return 2.0f * (float)saasin(len_v2v2(v2, v1) / 2.0f);
 }
 
+/**
+ * angle between 2 vectors defined by 3 coords, about an axis. */
+float angle_on_axis_v3v3v3_v3(const float v1[3], const float v2[3], const float v3[3], const float axis[3])
+{
+	float v1_proj[3], v2_proj[3], tproj[3];
+
+	sub_v3_v3v3(v1_proj, v1, v2);
+	sub_v3_v3v3(v2_proj, v3, v2);
+
+	/* project the vectors onto the axis */
+	project_v3_v3v3(tproj, v1_proj, axis);
+	sub_v3_v3(v1_proj, tproj);
+
+	project_v3_v3v3(tproj, v2_proj, axis);
+	sub_v3_v3(v2_proj, tproj);
+
+	return angle_v3v3(v1_proj, v2_proj);
+}
+
 void angle_tri_v3(float angles[3], const float v1[3], const float v2[3], const float v3[3])
 {
 	float ed1[3], ed2[3], ed3[3];