add mathutils.geometry.box_fit_2d() to wrap BLI_convexhull_aabb_fit_points_2d()

4 files changed, 93 insertions, 49 deletions

diff --git a/source/blender/blenlib/BLI_convexhull2d.h b/source/blender/blenlib/BLI_convexhull2d.h
index d6b5acbb95e..3f0787b37b1 100644
--- a/source/blender/blenlib/BLI_convexhull2d.h
+++ b/source/blender/blenlib/BLI_convexhull2d.h
@@ -25,9 +25,10 @@
  *  \ingroup bli
  */
 
-int BLI_convexhull_2d_presorted(const float (*points)[2], const int n, int r_points[]);
+int BLI_convexhull_2d_sorted(const float (*points)[2], const int n, int r_points[]);
 int BLI_convexhull_2d(const float (*points)[2], const int n, int r_points[]);
 
-float BLI_convexhull_aabb_fit_2d(const float (*points_hull)[2], unsigned int n);
+float BLI_convexhull_aabb_fit_hull_2d(const float (*points_hull)[2], unsigned int n);
+float BLI_convexhull_aabb_fit_points_2d(const float (*points)[2], unsigned int n);
 
 #endif  /* __BLI_CONVEXHULL2D__ */
diff --git a/source/blender/blenlib/intern/convexhull2d.c b/source/blender/blenlib/intern/convexhull2d.c
index 16bbf464d65..536bb6d94e3 100644
--- a/source/blender/blenlib/intern/convexhull2d.c
+++ b/source/blender/blenlib/intern/convexhull2d.c
@@ -60,7 +60,7 @@ static float is_left(const float p0[2], const float p1[2], const float p2[2])
  * \param  r_points  An array of the convex hull vertex indices (max is n).
  * \returns the number of points in r_points.
  */
-int BLI_convexhull_2d_presorted(const float (*points)[2], const int n, int r_points[])
+int BLI_convexhull_2d_sorted(const float (*points)[2], const int n, int r_points[])
 {
 	/* the output array r_points[] will be used as the stack */
 	int bot = 0;
@@ -207,7 +207,7 @@ int BLI_convexhull_2d(const float (*points)[2], const int n, int r_points[])
 		memcpy(points_sort[i], points_ref[i].pt, sizeof(float[2]));
 	}
 
-	tot = BLI_convexhull_2d_presorted((const float (*)[2])points_sort, n, r_points);
+	tot = BLI_convexhull_2d_sorted((const float (*)[2])points_sort, n, r_points);
 
 	/* map back to the original index values */
 	points_map = (int *)points_sort;  /* abuse float array for temp storage */
@@ -237,9 +237,12 @@ int BLI_convexhull_2d(const float (*points)[2], const int n, int r_points[])
  *
  * Intended to be used with #BLI_convexhull_2d
  *
+ * \param points  Orded hull points
+ * (result of #BLI_convexhull_2d mapped to a contiguous array).
+ *
  * \note we could return the index of the best edge too if its needed.
  */
-float BLI_convexhull_aabb_fit_2d(const float (*points_hull)[2], unsigned int n)
+float BLI_convexhull_aabb_fit_hull_2d(const float (*points_hull)[2], unsigned int n)
 {
 	unsigned int i, i_prev;
 	float area_best = FLT_MAX;
@@ -289,4 +292,42 @@ float BLI_convexhull_aabb_fit_2d(const float (*points_hull)[2], unsigned int n)
 
 	return angle_best;
 }
+
+/**
+ * Wrap #BLI_convexhull_aabb_fit_hull_2d and do the convex hull calculation.
+ *
+ * \param points  arbitrary 2d points.
+ */
+float BLI_convexhull_aabb_fit_points_2d(const float (*points)[2], unsigned int n)
+{
+	int *index_map;
+	int tot;
+
+	float angle;
+
+	index_map = MEM_mallocN(sizeof(*index_map) * n, __func__);
+
+	tot = BLI_convexhull_2d((const float (*)[2])points, (int)n, index_map);
+
+	if (tot) {
+		float (*points_hull)[2];
+		int j;
+
+		points_hull = MEM_mallocN(sizeof(*points_hull) * (size_t)tot, __func__);
+		for (j = 0; j < tot; j++) {
+			copy_v2_v2(points_hull[j], points[index_map[j]]);
+		}
+
+		angle = BLI_convexhull_aabb_fit_hull_2d((const float (*)[2])points_hull, (unsigned int)tot);
+		MEM_freeN(points_hull);
+	}
+	else {
+		angle = 0.0f;
+	}
+
+	MEM_freeN(index_map);
+
+	return angle;
+}
+
 /** \} */
diff --git a/source/blender/editors/uvedit/uvedit_parametrizer.c b/source/blender/editors/uvedit/uvedit_parametrizer.c
index 4bc7aa8e2d0..f0e97ffe3b1 100644
--- a/source/blender/editors/uvedit/uvedit_parametrizer.c
+++ b/source/blender/editors/uvedit/uvedit_parametrizer.c
@@ -4483,8 +4483,8 @@ static void param_pack_rotate(ParamHandle *handle)
 
 	for (i = 0; i < phandle->ncharts; i++) {
 		float (*points)[2];
-		int *index_map;
 		int tot;
+		float angle;
 
 		chart = phandle->charts[i];
 
@@ -4493,34 +4493,18 @@ static void param_pack_rotate(ParamHandle *handle)
 		}
 
 		points = MEM_mallocN(sizeof(*points) * chart->nverts, __func__);
-		index_map = MEM_mallocN(sizeof(*index_map) * chart->nverts, __func__);
 
 		p_chart_uv_to_array(chart, points);
 
-		tot = BLI_convexhull_2d((const float (*)[2])points, chart->nverts, index_map);
+		angle = BLI_convexhull_aabb_fit_points_2d((const float (*)[2])points, tot);
 
-		if (tot) {
-			float (*points_hull)[2];
-			int j;
-			float angle;
-
-			points_hull = MEM_mallocN(sizeof(*points) * tot, __func__);
-			for (j = 0; j < tot; j++) {
-				copy_v2_v2(points_hull[j], points[index_map[j]]);
-			}
-
-			angle = BLI_convexhull_aabb_fit_2d((const float (*)[2])points_hull, tot);
-			MEM_freeN(points_hull);
+		MEM_freeN(points);
 
-			if (angle != 0.0f) {
-				float mat[2][2];
-				angle_to_mat2(mat, angle);
-				p_chart_uv_transform(chart, mat);
-			}
+		if (angle != 0.0f) {
+			float mat[2][2];
+			angle_to_mat2(mat, angle);
+			p_chart_uv_transform(chart, mat);
 		}
-
-		MEM_freeN(points);
-		MEM_freeN(index_map);
 	}
 }
 
diff --git a/source/blender/python/mathutils/mathutils_geometry.c b/source/blender/python/mathutils/mathutils_geometry.c
index a8c23d3b0f4..06aa0cb2753 100644
--- a/source/blender/python/mathutils/mathutils_geometry.c
+++ b/source/blender/python/mathutils/mathutils_geometry.c
@@ -1504,6 +1504,38 @@ static PyObject *M_Geometry_box_pack_2d(PyObject *UNUSED(self), PyObject *boxlis
 	return ret;
 }
 
+PyDoc_STRVAR(M_Geometry_box_fit_2d_doc,
+".. function:: box_fit_2d(points)\n"
+"\n"
+"   Returns a list of indices into the list given\n"
+"\n"
+"   :arg points: list of 2d points.\n"
+"   :type points: list\n"
+"   :return: a list of indices\n"
+"   :rtype: list of ints\n"
+);
+static PyObject *M_Geometry_box_fit_2d(PyObject *UNUSED(self), PyObject *pointlist)
+{
+	float (*points)[2];
+	Py_ssize_t len;
+
+	float angle = 0.0f;
+
+	len = mathutils_array_parse_alloc_v(((float **)&points), 2, pointlist, "box_fit_2d");
+	if (len == -1) {
+		return NULL;
+	}
+
+	if (len) {
+		/* Non Python function */
+		angle = BLI_convexhull_aabb_fit_points_2d((const float (*)[2])points, len);
+
+		PyMem_Free(points);
+	}
+
+
+	return PyFloat_FromDouble(angle);
+}
 
 PyDoc_STRVAR(M_Geometry_convex_hull_2d_doc,
 ".. function:: convex_hull_2d(points)\n"
@@ -1517,42 +1549,24 @@ PyDoc_STRVAR(M_Geometry_convex_hull_2d_doc,
 );
 static PyObject *M_Geometry_convex_hull_2d(PyObject *UNUSED(self), PyObject *pointlist)
 {
+	float (*points)[2];
 	Py_ssize_t len;
 
 	PyObject *ret;
 
-	if (!PyList_Check(pointlist)) {
-		PyErr_SetString(PyExc_TypeError,
-		                "expected a list of Vectors");
+	len = mathutils_array_parse_alloc_v(((float **)&points), 2, pointlist, "convex_hull_2d");
+	if (len == -1) {
 		return NULL;
 	}
 
-	len = PyList_GET_SIZE(pointlist);
 	if (len) {
-		float (*points)[2] = MEM_mallocN(sizeof(*points) * len, __func__);
 		int *index_map;
 		Py_ssize_t len_ret, i;
-		PyObject *list_item;
-		bool ok = true;
-
-		for (i = 0; i < len; i++) {
-			list_item = PyList_GET_ITEM(pointlist, i);
-			if (mathutils_array_parse(points[i], 2, 2, list_item, "convex_hull") == -1) {
-				ok = false;
-				break;
-			}
-		}
-
-		if (ok == false) {
-			MEM_freeN(points);
-			return NULL;
-		}
 
 		index_map  = MEM_mallocN(sizeof(*index_map) * len, __func__);
 
 		/* Non Python function */
 		len_ret = BLI_convexhull_2d((const float (*)[2])points, len, index_map);
-		MEM_freeN(points);
 
 		ret = PyList_New(len_ret);
 		for (i = 0; i < len_ret; i++) {
@@ -1560,11 +1574,14 @@ static PyObject *M_Geometry_convex_hull_2d(PyObject *UNUSED(self), PyObject *poi
 		}
 
 		MEM_freeN(index_map);
+
+		PyMem_Free(points);
 	}
 	else {
 		ret = PyList_New(0);
 	}
 
+
 	return ret;
 }
 
@@ -1593,6 +1610,7 @@ static PyMethodDef M_Geometry_methods[] = {
 	{"interpolate_bezier", (PyCFunction) M_Geometry_interpolate_bezier, METH_VARARGS, M_Geometry_interpolate_bezier_doc},
 	{"tessellate_polygon", (PyCFunction) M_Geometry_tessellate_polygon, METH_O, M_Geometry_tessellate_polygon_doc},
 	{"convex_hull_2d", (PyCFunction) M_Geometry_convex_hull_2d, METH_O, M_Geometry_convex_hull_2d_doc},
+	{"box_fit_2d", (PyCFunction) M_Geometry_box_fit_2d, METH_O, M_Geometry_box_fit_2d_doc},
 	{"box_pack_2d", (PyCFunction) M_Geometry_box_pack_2d, METH_O, M_Geometry_box_pack_2d_doc},
 #endif
 	{NULL, NULL, 0, NULL}