archive/blender-archive
Archived
1
1
Fork 0
Code Pull Requests Packages Activity

utility function volume_tetrahedron(), for mathutils and BLI math.

Browse Source
This commit is contained in:
Campbell Barton
2013-04-21 13:24:45 +00:00
parent 1fe7657b4f
commit c667f1ff10
3 changed files with 63 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
source/blender/blenlib/BLI_math_geom.h
View File

@@ -61,6 +61,8 @@ float area_quad_v3(const float a[3], const float b[3], const float c[3], const f
float area_poly_v3(int nr, float verts[][3], const float normal[3]);
float area_poly_v2(int nr, float verts[][2]);
float volume_tetrahedron_v3(const float v1[3], const float v2[3], const float v3[3], const float v4[3]);
int is_quad_convex_v3(const float v1[3], const float v2[3], const float v3[3], const float v4[3]);
int is_quad_convex_v2(const float v1[2], const float v2[2], const float v3[2], const float v4[2]);

15
source/blender/blenlib/intern/math_geom.c
View File

@@ -183,6 +183,21 @@ float area_poly_v2(int nr, float verts[][2])
return fabsf(0.5f * area);
}
/********************************* Volume **********************************/
/**
* The volume from a tetrahedron, points can be in any order
*/
float volume_tetrahedron_v3(const float v1[3], const float v2[3], const float v3[3], const float v4[3])
{
float m[3][3];
sub_v3_v3v3(m[0], v1, v2);
sub_v3_v3v3(m[1], v2, v3);
sub_v3_v3v3(m[2], v3, v4);
return fabsf(determinant_m3_array(m)) / 6.0f;
}
/********************************* Distance **********************************/
/* distance p to line v1-v2

46
source/blender/python/mathutils/mathutils_geometry.c
View File

@@ -467,6 +467,51 @@ static PyObject *M_Geometry_area_tri(PyObject *UNUSED(self), PyObject *args)
}
}
PyDoc_STRVAR(M_Geometry_volume_tetrahedron_doc,
".. function:: volume_tetrahedron(v1, v2, v3, v4)\n"
"\n"
" Return the volume formed by a tetrahedron (points can be in any order).\n"
"\n"
" :arg v1: Point1\n"
" :type v1: :class:`mathutils.Vector`\n"
" :arg v2: Point2\n"
" :type v2: :class:`mathutils.Vector`\n"
" :arg v3: Point3\n"
" :type v3: :class:`mathutils.Vector`\n"
" :arg v4: Point4\n"
" :type v4: :class:`mathutils.Vector`\n"
" :rtype: float\n"
);
static PyObject *M_Geometry_volume_tetrahedron(PyObject *UNUSED(self), PyObject *args)
{
VectorObject *vec1, *vec2, *vec3, *vec4;
if (!PyArg_ParseTuple(args, "O!O!O!O!:volume_tetrahedron",
&vector_Type, &vec1,
&vector_Type, &vec2,
&vector_Type, &vec3,
&vector_Type, &vec4))
{
return NULL;
}
if (vec1->size < 3 || vec2->size < 3 || vec3->size < 3 || vec4->size < 3) {
PyErr_SetString(PyExc_ValueError,
"geometry.volume_tetrahedron(...): "
" can't use 2D Vectors");
return NULL;
}
if (BaseMath_ReadCallback(vec1) == -1 ||
BaseMath_ReadCallback(vec2) == -1 ||
BaseMath_ReadCallback(vec3) == -1 ||
BaseMath_ReadCallback(vec4) == -1)
{
return NULL;
}
return PyFloat_FromDouble(volume_tetrahedron_v3(vec1->vec, vec2->vec, vec3->vec, vec4->vec));
}
PyDoc_STRVAR(M_Geometry_intersect_line_line_2d_doc,
".. function:: intersect_line_line_2d(lineA_p1, lineA_p2, lineB_p1, lineB_p2)\n"
@@ -1458,6 +1503,7 @@ static PyMethodDef M_Geometry_methods[] = {
{"distance_point_to_plane", (PyCFunction) M_Geometry_distance_point_to_plane, METH_VARARGS, M_Geometry_distance_point_to_plane_doc},
{"intersect_sphere_sphere_2d", (PyCFunction) M_Geometry_intersect_sphere_sphere_2d, METH_VARARGS, M_Geometry_intersect_sphere_sphere_2d_doc},
{"area_tri", (PyCFunction) M_Geometry_area_tri, METH_VARARGS, M_Geometry_area_tri_doc},
{"volume_tetrahedron", (PyCFunction) M_Geometry_volume_tetrahedron, METH_VARARGS, M_Geometry_volume_tetrahedron_doc},
{"normal", (PyCFunction) M_Geometry_normal, METH_VARARGS, M_Geometry_normal_doc},
{"barycentric_transform", (PyCFunction) M_Geometry_barycentric_transform, METH_VARARGS, M_Geometry_barycentric_transform_doc},
{"points_in_planes", (PyCFunction) M_Geometry_points_in_planes, METH_VARARGS, M_Geometry_points_in_planes_doc},