4 files changed, 130 insertions, 0 deletions

diff --git a/release/scripts/startup/bl_ui/space_view3d.py b/release/scripts/startup/bl_ui/space_view3d.py
index 781ebd32318..9f4d0f8dcc1 100644
--- a/release/scripts/startup/bl_ui/space_view3d.py
+++ b/release/scripts/startup/bl_ui/space_view3d.py
@@ -1828,6 +1828,7 @@ class VIEW3D_MT_edit_mesh(Menu):
 
         layout.operator("mesh.symmetrize")
         layout.operator("mesh.symmetry_snap")
+        layout.operator("mesh.bisect")
         layout.operator_menu_enum("mesh.sort_elements", "type", text="Sort Elements...")
 
         layout.separator()
diff --git a/source/blender/editors/mesh/editmesh_tools.c b/source/blender/editors/mesh/editmesh_tools.c
index 877e62a01f4..a6202b01ea4 100644
--- a/source/blender/editors/mesh/editmesh_tools.c
+++ b/source/blender/editors/mesh/editmesh_tools.c
@@ -4435,6 +4435,133 @@ void MESH_OT_convex_hull(wmOperatorType *ot)
 }
 #endif
 
+
+static int mesh_bisect_exec(bContext *C, wmOperator *op)
+{
+	Scene *scene = CTX_data_scene(C);
+
+	/* both can be NULL, fallbacks values are used */
+	View3D *v3d = CTX_wm_view3d(C);
+	RegionView3D *rv3d = ED_view3d_context_rv3d(C);
+
+	Object *obedit = CTX_data_edit_object(C);
+	BMEditMesh *em = BKE_editmesh_from_object(obedit);
+	BMesh *bm = em->bm;
+	BMOperator bmop;
+	float plane_co[3];
+	float plane_no[3];
+	float imat[4][4];
+
+	const float thresh = RNA_float_get(op->ptr, "threshold");
+	const bool use_fill = RNA_boolean_get(op->ptr, "use_fill");
+	const bool clear_inner = RNA_boolean_get(op->ptr, "clear_inner");
+	const bool clear_outer = RNA_boolean_get(op->ptr, "clear_outer");
+
+	PropertyRNA *prop;
+
+	prop = RNA_struct_find_property(op->ptr, "plane_co");
+	if (RNA_property_is_set(op->ptr, prop)) {
+		RNA_property_float_get_array(op->ptr, prop, plane_co);
+	}
+	else {
+		copy_v3_v3(plane_co, give_cursor(scene, v3d));
+		RNA_property_float_set_array(op->ptr, prop, plane_co);
+	}
+
+	prop = RNA_struct_find_property(op->ptr, "plane_no");
+	if (RNA_property_is_set(op->ptr, prop)) {
+		RNA_property_float_get_array(op->ptr, prop, plane_no);
+	}
+	else {
+		if (rv3d) {
+			copy_v3_v3(plane_no, rv3d->viewinv[1]);
+		}
+		else {
+			/* fallback... */
+			plane_no[0] = plane_no[1] = 0.0f; plane_no[2] = 1.0f;
+		}
+		RNA_property_float_set_array(op->ptr, prop, plane_no);
+	}
+
+	invert_m4_m4(imat, obedit->obmat);
+	mul_m4_v3(imat, plane_co);
+	mul_mat3_m4_v3(imat, plane_no);
+	normalize_v3(plane_no);
+
+	EDBM_op_init(em, &bmop, op,
+	             "bisect_plane geom=%hvef plane_co=%v plane_no=%v dist=%f clear_inner=%b clear_outer=%b",
+	             BM_ELEM_SELECT, plane_co, plane_no, thresh, clear_inner, clear_outer);
+	BMO_op_exec(bm, &bmop);
+
+	if (use_fill) {
+		float normal_fill[3];
+		BMOperator bmop_fill;
+		BMOperator bmop_attr;
+
+		normalize_v3_v3(normal_fill, plane_no);
+		if (clear_outer == true && clear_inner == false) {
+			negate_v3(normal_fill);
+		}
+
+		/* Fill */
+		BMO_op_initf(
+		        bm, &bmop_fill, op->flag,
+		        "triangle_fill edges=%S normal=%v use_dissolve=%b",
+		        &bmop, "geom_cut.out", normal_fill, true);
+		BMO_op_exec(bm, &bmop_fill);
+
+		/* Copy Attributes */
+		BMO_op_initf(bm, &bmop_attr, op->flag,
+		             "face_attribute_fill faces=%S use_normals=%b use_data=%b",
+		             &bmop_fill, "geom.out", false, true);
+		BMO_op_exec(bm, &bmop_attr);
+		BMO_op_finish(bm, &bmop_attr);
+		BMO_op_finish(bm, &bmop_fill);
+	}
+
+	EDBM_flag_disable_all(em, BM_ELEM_SELECT);
+	BMO_slot_buffer_hflag_enable(bm, bmop.slots_out, "geom_cut.out", BM_VERT | BM_EDGE, BM_ELEM_SELECT, true);
+
+	if (!EDBM_op_finish(em, &bmop, op, true)) {
+		return OPERATOR_CANCELLED;
+	}
+	else {
+		EDBM_update_generic(em, true, true);
+		EDBM_selectmode_flush(em);
+		return OPERATOR_FINISHED;
+	}
+}
+
+void MESH_OT_bisect(struct wmOperatorType *ot)
+{
+	PropertyRNA *prop;
+
+	/* identifiers */
+	ot->name = "Bisect";
+	ot->description = "Enforce symmetry (both form and topological) across an axis";
+	ot->idname = "MESH_OT_bisect";
+
+	/* api callbacks */
+	ot->exec = mesh_bisect_exec;
+	ot->poll = ED_operator_editmesh;
+
+	/* flags */
+	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+
+	prop = RNA_def_float_vector(ot->srna, "plane_co", 3, NULL, -FLT_MAX, FLT_MAX, "Point", "", -FLT_MAX, FLT_MAX);
+	RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+	prop = RNA_def_float_vector(ot->srna, "plane_no", 3, NULL, -FLT_MAX, FLT_MAX, "Direction", "", -FLT_MAX, FLT_MAX);
+	RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+
+	RNA_def_boolean(ot->srna, "use_fill", false, "Fill", "Fill in the cut");
+	RNA_def_boolean(ot->srna, "clear_inner", false, "Clear Inner", "Remove geometry behind the plane");
+	RNA_def_boolean(ot->srna, "clear_outer", false, "Clear Outer", "Remove geometry infront of the plane");
+
+	RNA_def_float(ot->srna, "threshold", 0.0001, 0.0, 10.0, "Axis Threshold", "", 0.00001, 0.1);
+
+}
+
 static int mesh_symmetrize_exec(bContext *C, wmOperator *op)
 {
 	Object *obedit = CTX_data_edit_object(C);
diff --git a/source/blender/editors/mesh/mesh_intern.h b/source/blender/editors/mesh/mesh_intern.h
index 1dcc0e64183..be9243dc7ef 100644
--- a/source/blender/editors/mesh/mesh_intern.h
+++ b/source/blender/editors/mesh/mesh_intern.h
@@ -171,6 +171,7 @@ void MESH_OT_edge_split(struct wmOperatorType *ot);
 void MESH_OT_bridge_edge_loops(struct wmOperatorType *ot);
 void MESH_OT_wireframe(struct wmOperatorType *ot);
 void MESH_OT_convex_hull(struct wmOperatorType *ot);
+void MESH_OT_bisect(struct wmOperatorType *ot);
 void MESH_OT_symmetrize(struct wmOperatorType *ot);
 void MESH_OT_symmetry_snap(struct wmOperatorType *ot);
 void MESH_OT_shape_propagate_to_all(struct wmOperatorType *ot);
diff --git a/source/blender/editors/mesh/mesh_ops.c b/source/blender/editors/mesh/mesh_ops.c
index b5352fb35f4..c98ad13acf6 100644
--- a/source/blender/editors/mesh/mesh_ops.c
+++ b/source/blender/editors/mesh/mesh_ops.c
@@ -175,6 +175,7 @@ void ED_operatortypes_mesh(void)
 	WM_operatortype_append(MESH_OT_convex_hull);
 #endif
 
+	WM_operatortype_append(MESH_OT_bisect);
 	WM_operatortype_append(MESH_OT_symmetrize);
 	WM_operatortype_append(MESH_OT_symmetry_snap);