==Python API==

Blender.Geometry.ClosestPointOnLine(pt, vec1, vec2) -> (pt, lambda)
This wraps lambda_cp_line_ex

Needed for experemental tree generator

2 files changed, 51 insertions, 0 deletions

diff --git a/source/blender/python/api2_2x/Geometry.c b/source/blender/python/api2_2x/Geometry.c
index fcfe1eeae04..a3b2bc8b244 100644
--- a/source/blender/python/api2_2x/Geometry.c
+++ b/source/blender/python/api2_2x/Geometry.c
@@ -47,6 +47,7 @@
  
 #include "BKE_utildefines.h"
 #include "BLI_boxpack2d.h"
+#include "BLI_arithb.h"
 
 #define SWAP_FLOAT(a,b,tmp) tmp=a; a=b; b=tmp
 #define eul 0.000001
@@ -54,19 +55,23 @@
 /*-- forward declarations -- */
 static PyObject *M_Geometry_PolyFill( PyObject * self, PyObject * polyLineSeq );
 static PyObject *M_Geometry_LineIntersect2D( PyObject * self, PyObject * args );
+static PyObject *M_Geometry_ClosestPointOnLine( PyObject * self, PyObject * args );
 static PyObject *M_Geometry_PointInTriangle2D( PyObject * self, PyObject * args );
 static PyObject *M_Geometry_BoxPack2D( PyObject * self, PyObject * args );
 
+
 /*-------------------------DOC STRINGS ---------------------------*/
 static char M_Geometry_doc[] = "The Blender Geometry module\n\n";
 static char M_Geometry_PolyFill_doc[] = "(veclist_list) - takes a list of polylines (each point a vector) and returns the point indicies for a polyline filled with triangles";
 static char M_Geometry_LineIntersect2D_doc[] = "(lineA_p1, lineA_p2, lineB_p1, lineB_p2) - takes 2 lines (as 4 vectors) and returns a vector for their point of intersection or None";
+static char M_Geometry_ClosestPointOnLine_doc[] = "(pt, line_p1, line_p2) - takes a point and a line and returns a (Vector, Bool) for the point on the line, and the bool so you can know if the point was between the 2 points";
 static char M_Geometry_PointInTriangle2D_doc[] = "(pt, tri_p1, tri_p2, tri_p3) - takes 4 vectors, one is the point and the next 3 define the triabgle, only the x and y are used from the vectors";
 static char M_Geometry_BoxPack2D_doc[] = "";
 /*-----------------------METHOD DEFINITIONS ----------------------*/
 struct PyMethodDef M_Geometry_methods[] = {
 	{"PolyFill", ( PyCFunction ) M_Geometry_PolyFill, METH_O, M_Geometry_PolyFill_doc},
 	{"LineIntersect2D", ( PyCFunction ) M_Geometry_LineIntersect2D, METH_VARARGS, M_Geometry_LineIntersect2D_doc},
+	{"ClosestPointOnLine", ( PyCFunction ) M_Geometry_ClosestPointOnLine, METH_VARARGS, M_Geometry_ClosestPointOnLine_doc},
 	{"PointInTriangle2D", ( PyCFunction ) M_Geometry_PointInTriangle2D, METH_VARARGS, M_Geometry_PointInTriangle2D_doc},
 	{"BoxPack2D", ( PyCFunction ) M_Geometry_BoxPack2D, METH_O, M_Geometry_BoxPack2D_doc},
 	{NULL, NULL, 0, NULL}
@@ -277,6 +282,45 @@ static PyObject *M_Geometry_LineIntersect2D( PyObject * self, PyObject * args )
 	Py_RETURN_NONE;
 }
 
+static PyObject *M_Geometry_ClosestPointOnLine( PyObject * self, PyObject * args )
+{
+	VectorObject *pt, *line_1, *line_2;
+	float pt_in[3], pt_out[3], l1[3], l2[3];
+	float lambda;
+	PyObject *ret, *val1, *val2;
+	
+	if( !PyArg_ParseTuple ( args, "O!O!O!",
+	&vector_Type, &pt,
+	&vector_Type, &line_1,
+	&vector_Type, &line_2)
+	  )
+		return ( EXPP_ReturnPyObjError
+				( PyExc_TypeError, "expected 3 vector types\n" ) );
+	
+	/* accept 2d verts */
+	if (pt->size==3) { VECCOPY(pt_in, pt->vec);}
+	else { pt_in[2]=0.0;	VECCOPY2D(pt_in, pt->vec) }
+	
+	if (line_1->size==3) { VECCOPY(l1, line_1->vec);}
+	else { l1[2]=0.0;	VECCOPY2D(l1, line_1->vec) }
+	
+	if (line_2->size==3) { VECCOPY(l2, line_2->vec);}
+	else { l2[2]=0.0;	VECCOPY2D(l2, line_2->vec) }
+	
+	/* do the calculation */
+	lambda = lambda_cp_line_ex(pt_in, l1, l2, pt_out);
+	
+	val1 = newVectorObject(pt_out, 3, Py_NEW);
+	val2 = PyFloat_FromDouble(lambda);
+	
+	ret = PyTuple_Pack(2, val1, val2);
+	
+	Py_DECREF(val1);
+	Py_DECREF(val2);
+	
+	return ret;
+}
+
 #define SIDE_OF_LINE(pa,pb,pp)	((pa[0]-pp[0])*(pb[1]-pp[1]))-((pb[0]-pp[0])*(pa[1]-pp[1]))
 #define POINT_IN_TRI(p0,p1,p2,p3)	((SIDE_OF_LINE(p1,p2,p0)>=0) && (SIDE_OF_LINE(p2,p3,p0)>=0) && (SIDE_OF_LINE(p3,p1,p0)>=0))
 
diff --git a/source/blender/python/api2_2x/doc/Geometry.py b/source/blender/python/api2_2x/doc/Geometry.py
index 7c7e91a1a71..f882f4b3b57 100644
--- a/source/blender/python/api2_2x/doc/Geometry.py
+++ b/source/blender/python/api2_2x/doc/Geometry.py
@@ -48,6 +48,13 @@ def LineIntersect2D(vec1, vec2, vec3, vec4):
 	@return: a 2D Vector for the intersection or None where there is no intersection.
 	"""
 
+def ClosestPointOnLine(pt, vec1, vec2):
+	"""
+	Takes 2 lines vec1, vec2 for the 2 points of the first line and vec2, vec3 for the 2 points of the second line.
+	@rtype: tuple
+	@return: a tuple containing a vector and a float, the vector is the closest point on the line, the float is the position on the line, between 0 and 1 the point is on the line.
+	"""
+
 def PointInTriangle2D(pt, tri_pt1, tri_pt2, tri_pt3):
 	"""
 	Takes 4 vectors (one for the test point and 3 for the triangle)