renamed math functions and made public

 lambda_cp_line --> line_point_factor_v3
 lambda_cp_line2 --> line_point_factor_v2

correction to previous commit function name
 isect_seg_sphere_v3 --> isect_line_sphere_v3
 ... since its not clipped.

added a clip argument to the python version of the function.

4 files changed, 48 insertions, 37 deletions

diff --git a/source/blender/blenlib/BLI_math_geom.h b/source/blender/blenlib/BLI_math_geom.h
index 26cf315fc36..c905ada184d 100644
--- a/source/blender/blenlib/BLI_math_geom.h
+++ b/source/blender/blenlib/BLI_math_geom.h
@@ -66,6 +66,9 @@ float closest_to_line_v3(float r[3], const float p[3], const float l1[3], const
 float closest_to_line_v2(float r[2], const float p[2], const float l1[2], const float l2[2]);
 void closest_to_line_segment_v3(float r[3], const float p[3], const float l1[3], const float l2[3]);
 
+float line_point_factor_v3(const float p[3], const float l1[3], const float l2[3]);
+float line_point_factor_v2(const float p[2], const float l1[2], const float l2[2]);
+
 /******************************* Intersection ********************************/
 
 /* TODO int return value consistency */
@@ -78,8 +81,8 @@ void closest_to_line_segment_v3(float r[3], const float p[3], const float l1[3],
 
 int isect_line_line_v2(const float a1[2], const float a2[2], const float b1[2], const float b2[2]);
 int isect_line_line_v2_int(const int a1[2], const int a2[2], const int b1[2], const int b2[2]);
+int isect_line_sphere_v3(const float l1[3], const float l2[3], const float sp[3], const float r, float r_p1[3], float r_p2[3]);
 int isect_seg_seg_v2_point(const float v1[2], const float v2[2], const float v3[2], const float v4[2], float vi[2]);
-int isect_seg_sphere_v3(const float l1[3], const float l2[3], const float sp[3], const float r, float r_p1[3], float r_p2[3]);
 
 /* Returns the number of point of interests
  * 0 - lines are colinear
diff --git a/source/blender/blenlib/intern/math_geom.c b/source/blender/blenlib/intern/math_geom.c
index ce03143dcaf..a71b60896fc 100644
--- a/source/blender/blenlib/intern/math_geom.c
+++ b/source/blender/blenlib/intern/math_geom.c
@@ -37,8 +37,6 @@
 #include "BLI_memarena.h"
 #include "BLI_utildefines.h"
 
-static float lambda_cp_line(const float p[3], const float l1[3], const float l2[3]);
-
 /********************************** Polygons *********************************/
 
 void cent_tri_v3(float cent[3], const float v1[3], const float v2[3], const float v3[3])
@@ -349,9 +347,9 @@ int isect_seg_seg_v2_point(const float v1[2], const float v2[2], const float v3[
 	return -1;
 }
 
-int isect_seg_sphere_v3(const float l1[3], const float l2[3],
-                        const float sp[3], const float r,
-                        float r_p1[3], float r_p2[3])
+int isect_line_sphere_v3(const float l1[3], const float l2[3],
+                         const float sp[3], const float r,
+                         float r_p1[3], float r_p2[3])
 {
 	/* l1:         coordinates (point of line)
 	 * l2:         coordinates (point of line)
@@ -741,7 +739,7 @@ int isect_line_plane_v3(float out[3], const float l1[3], const float l2[3], cons
 
 		add_v3_v3v3(l1_plane, l1, p_no);
 
-		dist = lambda_cp_line(plane_co, l1, l1_plane);
+		dist = line_point_factor_v3(plane_co, l1, l1_plane);
 
 		/* treat line like a ray, when 'no_flip' is set */
 		if(no_flip && dist < 0.0f) {
@@ -1191,7 +1189,7 @@ float closest_to_line_v2(float cp[2],const float p[2], const float l1[2], const
 }
 
 /* little sister we only need to know lambda */
-static float lambda_cp_line(const float p[3], const float l1[3], const float l2[3])
+float line_point_factor_v3(const float p[3], const float l1[3], const float l2[3])
 {
 	float h[3],u[3];
 	sub_v3_v3v3(u, l2, l1);
@@ -1199,6 +1197,14 @@ static float lambda_cp_line(const float p[3], const float l1[3], const float l2[
 	return(dot_v3v3(u,h)/dot_v3v3(u,u));
 }
 
+float line_point_factor_v2(const float p[2], const float l1[2], const float l2[2])
+{
+	float h[2], u[2];
+	sub_v2_v2v2(u, l2, l1);
+	sub_v2_v2v2(h, p, l1);
+	return(dot_v2v2(u, h)/dot_v2v2(u, u));
+}
+
 /* Similar to LineIntersectsTriangleUV, except it operates on a quad and in 2d, assumes point is in quad */
 void isect_point_quad_uv_v2(const float v0[2], const float v1[2], const float v2[2], const float v3[2], const float pt[2], float *uv)
 {
diff --git a/source/blender/editors/sculpt_paint/paint_image.c b/source/blender/editors/sculpt_paint/paint_image.c
index cae5c14aa97..c9a6aa87cd0 100644
--- a/source/blender/editors/sculpt_paint/paint_image.c
+++ b/source/blender/editors/sculpt_paint/paint_image.c
@@ -1174,25 +1174,6 @@ static void project_face_seams_init(const ProjPaintState *ps, const int face_ind
 #endif // PROJ_DEBUG_NOSEAMBLEED
 
 
-/* TODO - move to math_geom.c */
-
-/* little sister we only need to know lambda */
-#ifndef PROJ_DEBUG_NOSEAMBLEED
-static float lambda_cp_line2(const float p[2], const float l1[2], const float l2[2])
-{
-	float h[2], u[2];
-	
-	u[0] = l2[0] - l1[0];
-	u[1] = l2[1] - l1[1];
-
-	h[0] = p[0] - l1[0];
-	h[1] = p[1] - l1[1];
-	
-	return(dot_v2v2(u, h)/dot_v2v2(u, u));
-}
-#endif // PROJ_DEBUG_NOSEAMBLEED
-
-
 /* Converts a UV location to a 3D screenspace location
  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
  * 
@@ -2518,9 +2499,9 @@ static void project_paint_face_init(const ProjPaintState *ps, const int thread_i
 										*/
 										
 										/* Since this is a seam we need to work out where on the line this pixel is */
-										//fac = lambda_cp_line2(uv, uv_seam_quad[0], uv_seam_quad[1]);
+										//fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
 										
-										fac = lambda_cp_line2(uv, seam_subsection[0], seam_subsection[1]);
+										fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
 										if (fac < 0.0f)		{ VECCOPY(pixelScreenCo, edge_verts_inset_clip[0]); }
 										else if (fac > 1.0f)	{ VECCOPY(pixelScreenCo, edge_verts_inset_clip[1]); }
 										else				{ interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
diff --git a/source/blender/python/generic/mathutils_geometry.c b/source/blender/python/generic/mathutils_geometry.c
index 0b98867dcee..f3fe05cd846 100644
--- a/source/blender/python/generic/mathutils_geometry.c
+++ b/source/blender/python/generic/mathutils_geometry.c
@@ -522,7 +522,7 @@ static PyObject *M_Geometry_intersect_line_plane(PyObject *UNUSED(self), PyObjec
 	VectorObject *line_a, *line_b, *plane_co, *plane_no;
 	int no_flip= 0;
 	float isect[3];
-	if(!PyArg_ParseTuple(args, "O!O!O!O!|i:intersect_line_line_2d",
+	if(!PyArg_ParseTuple(args, "O!O!O!O!|i:intersect_line_plane",
 	  &vector_Type, &line_a,
 	  &vector_Type, &line_b,
 	  &vector_Type, &plane_co,
@@ -555,7 +555,7 @@ static PyObject *M_Geometry_intersect_line_plane(PyObject *UNUSED(self), PyObjec
 
 
 PyDoc_STRVAR(M_Geometry_intersect_line_sphere_doc,
-".. function:: intersect_line_sphere(line_a, line_b, sphere_co, sphere_radius)\n"
+".. function:: intersect_line_sphere(line_a, line_b, sphere_co, sphere_radius, clip=True)\n"
 "\n"
 "   Takes a lines (as 2 vectors), a sphere as a point and a radius and\n"
 "   returns the intersection\n"
@@ -576,15 +576,17 @@ static PyObject *M_Geometry_intersect_line_sphere(PyObject *UNUSED(self), PyObje
 	PyObject *ret;
 	VectorObject *line_a, *line_b, *sphere_co;
 	float sphere_radius;
+	int clip= TRUE;
+	float lambda;
 
 	float isect_a[3];
 	float isect_b[3];
 
-	if(!PyArg_ParseTuple(args, "O!O!O!f:intersect_line_sphere",
+	if(!PyArg_ParseTuple(args, "O!O!O!f|i:intersect_line_sphere",
 	  &vector_Type, &line_a,
 	  &vector_Type, &line_b,
 	  &vector_Type, &sphere_co,
-	  &sphere_radius)
+	  &sphere_radius, &clip)
 	) {
 		return NULL;
 	}
@@ -603,14 +605,33 @@ static PyObject *M_Geometry_intersect_line_sphere(PyObject *UNUSED(self), PyObje
 
 	ret= PyTuple_New(2);
 
-	switch(isect_seg_sphere_v3(line_a->vec, line_b->vec, sphere_co->vec, sphere_radius, isect_a, isect_b)) {
+	switch(isect_line_sphere_v3(line_a->vec, line_b->vec, sphere_co->vec, sphere_radius, isect_a, isect_b)) {
 	case 1:
-		PyTuple_SET_ITEM(ret, 0,  newVectorObject(isect_a, 3, Py_NEW, NULL));
+		/* ret 1 */
+		if(!clip || (((lambda= line_point_factor_v3(isect_a, line_a->vec, line_b->vec)) >= 0.0f) && (lambda <= 1.0f))) {
+			PyTuple_SET_ITEM(ret, 0,  newVectorObject(isect_a, 3, Py_NEW, NULL));
+		}
+		else {
+			PyTuple_SET_ITEM(ret, 0,  Py_None); Py_INCREF(Py_None);
+		}
+		/* ret 2 */
 		PyTuple_SET_ITEM(ret, 1,  Py_None); Py_INCREF(Py_None);
 		break;
 	case 2:
-		PyTuple_SET_ITEM(ret, 0,  newVectorObject(isect_a, 3, Py_NEW, NULL));
-		PyTuple_SET_ITEM(ret, 1,  newVectorObject(isect_b, 3, Py_NEW, NULL));
+		/* ret 1 */
+		if(!clip || (((lambda= line_point_factor_v3(isect_a, line_a->vec, line_b->vec)) >= 0.0f) && (lambda <= 1.0f))) {
+			PyTuple_SET_ITEM(ret, 0,  newVectorObject(isect_a, 3, Py_NEW, NULL));
+		}
+		else {
+			PyTuple_SET_ITEM(ret, 0,  Py_None); Py_INCREF(Py_None);
+		}
+		/* ret 2 */
+		if(!clip || (((lambda= line_point_factor_v3(isect_b, line_a->vec, line_b->vec)) >= 0.0f) && (lambda <= 1.0f))) {
+			PyTuple_SET_ITEM(ret, 1,  newVectorObject(isect_b, 3, Py_NEW, NULL));
+		}
+		else {
+			PyTuple_SET_ITEM(ret, 1,  Py_None); Py_INCREF(Py_None);
+		}
 		break;
 	default:
 		PyTuple_SET_ITEM(ret, 0,  Py_None); Py_INCREF(Py_None);