patch [#34890] BMesh Poke Face.

by Francisco De La Cruz (xercesblue), with some of my own changes/improvements.

Converts faces to triangle-fans (useful to run on ngons).

To access select a group of faces and press "Alt+P" or alternatively select the operator from the Faces menu (Ctrl+F)

1 files changed, 124 insertions, 0 deletions

diff --git a/source/blender/bmesh/operators/bmo_poke.c b/source/blender/bmesh/operators/bmo_poke.c
new file mode 100644
index 00000000000..939bfb3b63e
--- /dev/null
+++ b/source/blender/bmesh/operators/bmo_poke.c
@@ -0,0 +1,124 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contributor(s): Francisco De La Cruz
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/bmesh/operators/bmo_poke.c
+ *  \ingroup bmesh
+ *
+ * Pokes a face.
+ *
+ * Splits a face into a triangle fan.
+ */
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_math.h"
+#include "BLI_array.h"
+
+#include "bmesh.h"
+
+#include "intern/bmesh_operators_private.h" /* own include */
+
+#define ELE_NEW 1
+
+/**
+ * Pokes a face
+ *
+ * Splits a face into a triangle fan.
+ * Iterate over all selected faces, create a new center vertex and
+ * create triangles between original face edges and new center vertex.
+ */
+void bmo_poke_exec(BMesh *bm, BMOperator *op)
+{
+	BMOIter oiter;
+	BMFace *f;
+
+	const float offset = BMO_slot_float_get(op->slots_in, "offset");
+	const int center_mode = BMO_slot_int_get(op->slots_in, "center_mode");
+
+	void (*bm_face_calc_center_fn)(BMFace *f, float r_cent[3]);
+
+	switch (center_mode) {
+		case BMOP_POKE_MEAN_WEIGHTED:
+			bm_face_calc_center_fn = BM_face_calc_center_mean_weighted;
+			break;
+		case BMOP_POKE_BOUNDS:
+			bm_face_calc_center_fn = BM_face_calc_center_bounds;
+			break;
+		case BMOP_POKE_MEAN:
+			bm_face_calc_center_fn = BM_face_calc_center_mean;
+			break;
+		default:
+			BLI_assert(0);
+			break;
+	}
+
+	BMO_ITER(f, &oiter, op->slots_in, "faces", BM_FACE) {
+		BMFace *f_new;
+		float f_center[3];
+		BMVert *v_center = NULL;
+		BMLoop *l_iter, *l_first;
+		/* only interpolate the centeral loop from the face once,
+		 * then copy to all others in the fan */
+		BMLoop *l_center_example;
+
+		int i;
+
+		bm_face_calc_center_fn(f, f_center);
+		v_center = BM_vert_create(bm, f_center, NULL, 0);
+		BMO_elem_flag_enable(bm, v_center, ELE_NEW);
+
+		/* handled by BM_loop_interp_from_face */
+		// BM_vert_interp_from_face(bm, v_center, f);
+
+		i = 0;
+		l_iter = l_first = BM_FACE_FIRST_LOOP(f);
+		do {
+			BMLoop *l_new;
+
+			f_new = BM_face_create_quad_tri(bm, l_iter->v, l_iter->next->v, v_center, NULL, f, false);
+			l_new = BM_FACE_FIRST_LOOP(f_new);
+
+			if (i == 0) {
+				l_center_example = l_new->prev;
+				BM_loop_interp_from_face(bm, l_center_example, f, true, true);
+			}
+			else {
+				BM_elem_attrs_copy(bm, bm, l_center_example, l_new->prev);
+			}
+
+			/* Copy Loop Data */
+			BM_elem_attrs_copy(bm, bm, l_iter, l_new);
+			BM_elem_attrs_copy(bm, bm, l_iter->next, l_new->next);
+
+			BMO_elem_flag_enable(bm, f_new, ELE_NEW);
+		} while (i++, (l_iter = l_iter->next) != l_first);
+
+		copy_v3_v3(v_center->no, f->no);
+		madd_v3_v3fl(v_center->co, v_center->no, offset);
+
+		/* Kill Face */
+		BM_face_kill(bm, f);
+	}
+
+	BMO_slot_buffer_from_enabled_flag(bm, op, op->slots_out, "verts.out", BM_VERT, ELE_NEW);
+	BMO_slot_buffer_from_enabled_flag(bm, op, op->slots_out, "faces.out", BM_FACE, ELE_NEW);
+}