bmesh: debugging function to help resolve issues with corrupt mesh data - BM_mesh_validate()

source/blender/bmesh/CMakeLists.txt

@@ -68,6 +68,8 @@ set(SRC
 	intern/bmesh_mesh.h
 	intern/bmesh_mesh_conv.c
 	intern/bmesh_mesh_conv.h
+	intern/bmesh_mesh_validate.c
+	intern/bmesh_mesh_validate.h
 	intern/bmesh_mods.c
 	intern/bmesh_mods.h
 	intern/bmesh_opdefines.c

source/blender/bmesh/bmesh.h

@@ -217,6 +217,7 @@ extern "C" {
 #include "intern/bmesh_marking.h"
 #include "intern/bmesh_mesh.h"
 #include "intern/bmesh_mesh_conv.h"
+#include "intern/bmesh_mesh_validate.h"
 #include "intern/bmesh_mods.h"
 #include "intern/bmesh_operators.h"
 #include "intern/bmesh_polygon.h"

source/blender/bmesh/intern/bmesh_mesh_validate.c

@@ -0,0 +1,172 @@
+/*
+ * ***** 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.
+ *
+ * The Original Code is Copyright (C) 2012 Blender Foundation.
+ * All rights reserved.
+ *
+ * Contributor(s): Campbell Barton
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/bmesh/intern/bmesh_mesh_validate.c
+ *  \ingroup bmesh
+ *
+ * BM mesh validation function.
+ */
+
+/* debug builds only */
+#ifdef DEBUG
+
+#include "bmesh.h"
+
+#include "bmesh_mesh_validate.h"
+
+
+/* macro which inserts the function name */
+#if defined __GNUC__ || defined __sun
+#  define ERRMSG(format, args...) { fprintf(stderr, "%s: " format ", " AT "\n", __func__, ##args); errtot++; } (void)0
+#else
+#  define ERRMSG(format, ...) { fprintf(stderr, "%s: " format ", " AT "\n", __func__, __VA_ARGS__); errtot++; } (void)0
+#endif
+
+/**
+ * Check of this BMesh is valid, this function can be slow since its intended to help with debugging.
+ *
+ * \return TRUE when the mesh is valid.
+ */
+int BM_mesh_validate(BMesh *bm)
+{
+	int errtot;
+
+	BMIter iter;
+	BMVert *v;
+	BMEdge *e;
+	BMFace *f;
+
+	int i, j;
+
+	errtot = -1;
+	fprintf(stderr, "\n");
+	ERRMSG("This is a debugging function and not intended for general use, running slow test!");
+
+	/* force recalc, even if tagged as valid, since this mesh is suspect! */
+	bm->elem_index_dirty |= BM_ALL;
+	BM_mesh_elem_index_ensure(bm, BM_ALL);
+
+	BM_ITER_INDEX(v, &iter, bm, BM_VERTS_OF_MESH, NULL, i) {
+		if (v->e) {
+			if (!BM_vert_in_edge(v->e, v)) {
+				ERRMSG("vert: %d - is not in its referenced edge: %d", i, BM_elem_index_get(v->e));
+			}
+		}
+	}
+
+	/* check edges */
+	BM_ITER_INDEX(e, &iter, bm, BM_EDGES_OF_MESH, NULL, i) {
+		if (e->v1 == e->v2)
+		ERRMSG("edge %d: duplicate index: %d", i, BM_elem_index_get(e->v1));
+	}
+
+	/* edge radial structure */
+	BM_ITER_INDEX(e, &iter, bm, BM_EDGES_OF_MESH, NULL, i) {
+		if (e->l) {
+			BMLoop *l_iter;
+			BMLoop *l_first;
+
+			j = 0;
+
+			l_iter = l_first = e->l;
+			/* we could do more checks here, but save for face checks */
+			do {
+				if (l_iter->e != e) {
+					ERRMSG("edge %d: has invalid loop, loop is of face %d", i, BM_elem_index_get(l_iter->f));
+				}
+				else if (BM_vert_in_edge(e, l_iter->v) == FALSE) {
+					ERRMSG("edge %d: has invalid loop with vert not in edge, loop is of face %d", i, BM_elem_index_get(l_iter->f));
+				}
+				else if (BM_vert_in_edge(e, l_iter->next->v) == FALSE) {
+					ERRMSG("edge %d: has invalid loop with next vert not in edge, loop is of face %d", i, BM_elem_index_get(l_iter->f));
+				}
+			} while ((l_iter = l_iter->radial_next) != l_first);
+		}
+	}
+
+	/* face structure */
+	BM_ITER_INDEX(f, &iter, bm, BM_FACES_OF_MESH, NULL, i) {
+		BMLoop *l_iter;
+		BMLoop *l_first;
+
+		l_iter = l_first = BM_FACE_FIRST_LOOP(f);
+
+		do {
+			BM_elem_flag_disable(l_iter,    BM_ELEM_INTERNAL_TAG);
+			BM_elem_flag_disable(l_iter->v, BM_ELEM_INTERNAL_TAG);
+			BM_elem_flag_disable(l_iter->e, BM_ELEM_INTERNAL_TAG);
+		} while ((l_iter = l_iter->next) != l_first);
+
+		j = 0;
+
+		l_iter = l_first = BM_FACE_FIRST_LOOP(f);
+		do {
+			if (BM_elem_flag_test(l_iter, BM_ELEM_INTERNAL_TAG)) {
+				ERRMSG("face %d: has duplicate loop at corner: %d", i, j);
+			}
+			if (BM_elem_flag_test(l_iter->v, BM_ELEM_INTERNAL_TAG)) {
+				ERRMSG("face %d: has duplicate vert: %d, at corner: %d", i, BM_elem_index_get(l_iter->v), j);
+			}
+			if (BM_elem_flag_test(l_iter->e, BM_ELEM_INTERNAL_TAG)) {
+				ERRMSG("face %d: has duplicate edge: %d, at corner: %d", i,  BM_elem_index_get(l_iter->e), j);
+			}
+
+			/* adjacent data checks */
+			if (l_iter->f != f) {
+				ERRMSG("face %d: has loop that points to face: %d at corner: %d", i, BM_elem_index_get(l_iter->f), j);
+			}
+			if (l_iter != l_iter->prev->next) {
+				ERRMSG("face %d: has invalid 'prev/next' at corner: %d", i, j);
+			}
+			if (l_iter != l_iter->next->prev) {
+				ERRMSG("face %d: has invalid 'next/prev' at corner: %d", i, j);
+			}
+			if (l_iter != l_iter->radial_prev->radial_next) {
+				ERRMSG("face %d: has invalid 'radial_prev/radial_next' at corner: %d", i, j);
+			}
+			if (l_iter != l_iter->radial_next->radial_prev) {
+				ERRMSG("face %d: has invalid 'radial_next/radial_prev' at corner: %d", i, j);
+			}
+
+			BM_elem_flag_enable(l_iter,    BM_ELEM_INTERNAL_TAG);
+			BM_elem_flag_enable(l_iter->v, BM_ELEM_INTERNAL_TAG);
+			BM_elem_flag_enable(l_iter->e, BM_ELEM_INTERNAL_TAG);
+			j++;
+		} while ((l_iter = l_iter->next) != l_first);
+
+		if (j != f->len) {
+			ERRMSG("face %d: has length if %d but should be %d", i, f->len, j);
+		}
+	}
+
+
+
+	ERRMSG("Finished - errors %d", errtot);
+
+	return TRUE;
+}
+
+
+#endif

source/blender/bmesh/intern/bmesh_mesh_validate.h

@@ -0,0 +1,35 @@
+/*
+ * ***** 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.
+ *
+ * The Original Code is Copyright (C) 2012 Blender Foundation.
+ * All rights reserved.
+ *
+ * Contributor(s): Campbell Barton
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+#ifndef __BMESH_MESH_VALIDATE_H__
+#define __BMESH_MESH_VALIDATE_H__
+
+/** \file blender/bmesh/intern/bmesh_mesh_validate.h
+ *  \ingroup bmesh
+ */
+
+int BM_mesh_validate(BMesh *bm);
+
+#endif /* __BMESH_MESH_VALIDATE_H__ */

source/blender/editors/mesh/bmesh_utils.c

@@ -527,6 +527,8 @@ static void *editbtMesh_to_undoMesh(void *emv, void *obdata)
 
 #endif
 
+	/* BM_mesh_validate(em->bm); */ /* for troubleshooting */
+
 	BMO_op_callf(em->bm, "bmesh_to_mesh mesh=%p notessellation=%b", &um->me, TRUE);
 	um->selectmode = em->selectmode;
 

source/blender/modifiers/intern/MOD_edgesplit.c

@@ -103,6 +103,8 @@ static DerivedMesh *doEdgeSplit(DerivedMesh *dm, EdgeSplitModifierData *emd, Obj
 	
 	BMO_pop(bm);
 
+	/* BM_mesh_validate(bm); */ /* for troubleshooting */
+
 	BLI_assert(em->looptris == NULL);
 	result = CDDM_from_BMEditMesh(em, NULL, TRUE, FALSE);
 	BMEdit_Free(em);