Triangulate modifier

Useful for bump map baking where a consistent triangulation should be enforced when baking/exporting/importing, to avoid artifacts caused by a different triangulation of the mesh by that which was used for baking by internal/external tools. 

documentation is here http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.65/More_Features

Will probably add some pictures too to demonstrate the issue that is solved more clearly.
Currently using the skin modifier icon, will soon change that.

Review by Brecht, thanks!

10 files changed, 197 insertions, 5 deletions

diff --git a/release/scripts/startup/bl_ui/properties_data_modifier.py b/release/scripts/startup/bl_ui/properties_data_modifier.py
index ea8ffbe6c9f..62461d800f6 100644
--- a/release/scripts/startup/bl_ui/properties_data_modifier.py
+++ b/release/scripts/startup/bl_ui/properties_data_modifier.py
@@ -1029,5 +1029,8 @@ class DATA_PT_modifiers(ModifierButtonsPanel, Panel):
         col.prop(md, "use_y_symmetry")
         col.prop(md, "use_z_symmetry")
 
+    def TRIANGULATE(self, layout, ob, md):
+        layout.prop(md, "use_beauty")
+
 if __name__ == "__main__":  # only for live edit.
     bpy.utils.register_module(__name__)
diff --git a/source/blender/blenkernel/intern/cdderivedmesh.c b/source/blender/blenkernel/intern/cdderivedmesh.c
index 3ade51d13eb..3181a0da1b0 100644
--- a/source/blender/blenkernel/intern/cdderivedmesh.c
+++ b/source/blender/blenkernel/intern/cdderivedmesh.c
@@ -2516,7 +2516,7 @@ void CDDM_calc_edges(DerivedMesh *dm)
 	EdgeHashIterator *ehi;
 	MPoly *mp = cddm->mpoly;
 	MLoop *ml;
-	MEdge *med;
+	MEdge *med, *origmed;
 	EdgeHash *eh = BLI_edgehash_new();
 	int v1, v2;
 	int *eindex;
@@ -2549,6 +2549,7 @@ void CDDM_calc_edges(DerivedMesh *dm)
 	CustomData_add_layer(&edgeData, CD_MEDGE, CD_CALLOC, NULL, numEdges);
 	CustomData_add_layer(&edgeData, CD_ORIGINDEX, CD_CALLOC, NULL, numEdges);
 
+	origmed = cddm->medge;
 	med = CustomData_get_layer(&edgeData, CD_MEDGE);
 	index = CustomData_get_layer(&edgeData, CD_ORIGINDEX);
 
@@ -2559,8 +2560,14 @@ void CDDM_calc_edges(DerivedMesh *dm)
 		BLI_edgehashIterator_getKey(ehi, &med->v1, &med->v2);
 		j = GET_INT_FROM_POINTER(BLI_edgehashIterator_getValue(ehi));
 
-		med->flag = ME_EDGEDRAW | ME_EDGERENDER;
-		*index = j == 0 ? ORIGINDEX_NONE : eindex[j - 1];
+		if(j == 0) {
+			med->flag = ME_EDGEDRAW | ME_EDGERENDER;
+			*index = ORIGINDEX_NONE;
+		}
+		else {
+			med->flag = ME_EDGEDRAW | ME_EDGERENDER | origmed[j - 1].flag;
+			*index = eindex[j - 1];
+		}
 
 		BLI_edgehashIterator_setValue(ehi, SET_INT_IN_POINTER(i));
 	}
diff --git a/source/blender/editors/space_outliner/outliner_draw.c b/source/blender/editors/space_outliner/outliner_draw.c
index 2c40e0e656d..4f640c579a5 100644
--- a/source/blender/editors/space_outliner/outliner_draw.c
+++ b/source/blender/editors/space_outliner/outliner_draw.c
@@ -1038,6 +1038,8 @@ static void tselem_draw_icon(uiBlock *block, int xmax, float x, float y, TreeSto
 						UI_icon_draw(x, y, ICON_MOD_WARP); break;
 					case eModifierType_Skin:
 						UI_icon_draw(x, y, ICON_MOD_SKIN); break;
+					case eModifierType_Triangulate:
+						UI_icon_draw(x, y, ICON_MOD_SKIN); break;
 
 					/* Default */
 					case eModifierType_None:
diff --git a/source/blender/editors/space_view3d/view3d_draw.c b/source/blender/editors/space_view3d/view3d_draw.c
index 7a1b97ff1d6..70c612d156b 100644
--- a/source/blender/editors/space_view3d/view3d_draw.c
+++ b/source/blender/editors/space_view3d/view3d_draw.c
@@ -1422,8 +1422,8 @@ ImBuf *view3d_read_backbuf(ViewContext *vc, short xmin, short ymin, short xmax,
 	
 	ibuf = IMB_allocImBuf((xmaxc - xminc + 1), (ymaxc - yminc + 1), 32, IB_rect);
 
-	view3d_validate_backbuf(vc); 
-	
+	view3d_validate_backbuf(vc);
+
 	glReadPixels(vc->ar->winrct.xmin + xminc,
 	             vc->ar->winrct.ymin + yminc,
 	             (xmaxc - xminc + 1),
diff --git a/source/blender/makesdna/DNA_modifier_types.h b/source/blender/makesdna/DNA_modifier_types.h
index 2c896e4893f..49b0534711e 100644
--- a/source/blender/makesdna/DNA_modifier_types.h
+++ b/source/blender/makesdna/DNA_modifier_types.h
@@ -76,6 +76,7 @@ typedef enum ModifierType {
 	eModifierType_Remesh            = 41,
 	eModifierType_Skin              = 42,
 	eModifierType_LaplacianSmooth   = 43,
+	eModifierType_Triangulate		= 44,
 	NUM_MODIFIER_TYPES
 } ModifierType;
 
@@ -1114,6 +1115,14 @@ enum {
 	MOD_SKIN_SMOOTH_SHADING = 1
 };
 
+/* Triangulate modifier */
+
+typedef struct TriangulateModifierData {
+	ModifierData modifier;
+	int beauty;
+	int pad;
+} TriangulateModifierData;
+
 /* Smooth modifier flags */
 #define MOD_LAPLACIANSMOOTH_X (1<<1)
 #define MOD_LAPLACIANSMOOTH_Y (1<<2)
diff --git a/source/blender/makesrna/intern/rna_modifier.c b/source/blender/makesrna/intern/rna_modifier.c
index 2e3f8feda44..1f6eb4af577 100644
--- a/source/blender/makesrna/intern/rna_modifier.c
+++ b/source/blender/makesrna/intern/rna_modifier.c
@@ -78,6 +78,7 @@ EnumPropertyItem modifier_type_items[] = {
 	{eModifierType_Skin, "SKIN", ICON_MOD_SKIN, "Skin", ""},
 	{eModifierType_Solidify, "SOLIDIFY", ICON_MOD_SOLIDIFY, "Solidify", ""},
 	{eModifierType_Subsurf, "SUBSURF", ICON_MOD_SUBSURF, "Subdivision Surface", ""},
+	{eModifierType_Triangulate, "TRIANGULATE", ICON_MOD_SKIN, "Triangulate", ""},
 	{0, "", 0, N_("Deform"), ""},
 	{eModifierType_Armature, "ARMATURE", ICON_MOD_ARMATURE, "Armature", ""},
 	{eModifierType_Cast, "CAST", ICON_MOD_CAST, "Cast", ""},
@@ -213,6 +214,8 @@ static StructRNA *rna_Modifier_refine(struct PointerRNA *ptr)
 			return &RNA_SkinModifier;
 		case eModifierType_LaplacianSmooth:
 			return &RNA_LaplacianSmoothModifier;
+		case eModifierType_Triangulate:
+			return &RNA_TriangulateModifier;
 		default:
 			return &RNA_Modifier;
 	}
@@ -3361,6 +3364,23 @@ static void rna_def_modifier_skin(BlenderRNA *brna)
 	RNA_def_property_update(prop, 0, "rna_Modifier_update");
 }
 
+static void rna_def_modifier_triangulate(BlenderRNA *brna)
+{
+	StructRNA *srna;
+	PropertyRNA *prop;
+
+	srna = RNA_def_struct(brna, "TriangulateModifier", "Modifier");
+	RNA_def_struct_ui_text(srna, "Triangulate Modifier", "Triangulate Mesh");
+	RNA_def_struct_sdna(srna, "TriangulateModifierData");
+	RNA_def_struct_ui_icon(srna, ICON_MOD_SKIN);
+
+	prop = RNA_def_property(srna, "use_beauty", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_sdna(prop, NULL, "beauty", 1);
+	RNA_def_property_ui_text(prop, "Beauty Subdivide", "Subdivide across shortest diagonal");
+	RNA_def_property_update(prop, 0, "rna_Modifier_update");
+
+}
+
 void RNA_def_modifier(BlenderRNA *brna)
 {
 	StructRNA *srna;
@@ -3468,6 +3488,7 @@ void RNA_def_modifier(BlenderRNA *brna)
 	rna_def_modifier_remesh(brna);
 	rna_def_modifier_skin(brna);
 	rna_def_modifier_laplaciansmooth(brna);
+	rna_def_modifier_triangulate(brna);
 }
 
 #endif
diff --git a/source/blender/modifiers/CMakeLists.txt b/source/blender/modifiers/CMakeLists.txt
index 3a7066ff41a..cf3bb05849a 100644
--- a/source/blender/modifiers/CMakeLists.txt
+++ b/source/blender/modifiers/CMakeLists.txt
@@ -94,6 +94,7 @@ set(SRC
 	intern/MOD_weightvgedit.c
 	intern/MOD_weightvgmix.c
 	intern/MOD_weightvgproximity.c
+	intern/MOD_triangulate.c
 
 	MOD_modifiertypes.h
 	intern/MOD_boolean_util.h
diff --git a/source/blender/modifiers/MOD_modifiertypes.h b/source/blender/modifiers/MOD_modifiertypes.h
index a4817ff775d..290ba193567 100644
--- a/source/blender/modifiers/MOD_modifiertypes.h
+++ b/source/blender/modifiers/MOD_modifiertypes.h
@@ -76,6 +76,7 @@ extern ModifierTypeInfo modifierType_DynamicPaint;
 extern ModifierTypeInfo modifierType_Remesh;
 extern ModifierTypeInfo modifierType_Skin;
 extern ModifierTypeInfo modifierType_LaplacianSmooth;
+extern ModifierTypeInfo modifierType_Triangulate;
 
 /* MOD_util.c */
 void modifier_type_init(ModifierTypeInfo *types[]);
diff --git a/source/blender/modifiers/intern/MOD_triangulate.c b/source/blender/modifiers/intern/MOD_triangulate.c
new file mode 100644
index 00000000000..a9ec30067bf
--- /dev/null
+++ b/source/blender/modifiers/intern/MOD_triangulate.c
@@ -0,0 +1,147 @@
+/*
+ * ***** 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): Antony Riakiotakis
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ *
+ */
+
+/** \file blender/modifiers/intern/MOD_triangulate.c
+ *  \ingroup modifiers
+ */
+#include <string.h>
+
+#include "MEM_guardedalloc.h"
+
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+#include "DNA_object_types.h"
+#include "DNA_modifier_types.h"
+
+#include "BLI_utildefines.h"
+#include "BLI_string.h"
+#include "BLI_array.h"
+
+#include "BKE_cdderivedmesh.h"
+#include "BKE_deform.h"
+#include "BKE_DerivedMesh.h"
+#include "BKE_mesh.h"
+#include "BKE_modifier.h"
+#include "BKE_tessmesh.h"
+
+#include "MOD_util.h"
+
+/* triangulation modifier, directly calls the bmesh operator */
+
+static DerivedMesh *triangulate(DerivedMesh *dm, char use_beauty)
+{
+	DerivedMesh *result;
+	BMesh *bm;
+
+	bm = DM_to_bmesh(dm);
+
+	BMO_push(bm, NULL);
+	BMO_op_callf(bm, BMO_FLAG_DEFAULTS,
+				  "triangulate faces=%af use_beauty=%b", use_beauty);
+
+	BMO_pop(bm);
+
+	result = CDDM_from_bmesh(bm, FALSE);
+	BM_mesh_free(bm);
+
+	CDDM_calc_edges(result);
+	CDDM_calc_normals(result);
+
+	return result;
+}
+
+
+static void initData(ModifierData *md)
+{
+	TriangulateModifierData *tmd = (TriangulateModifierData *)md;
+
+	/* Enable in editmode by default */
+	md->mode |= eModifierMode_Editmode;
+	tmd->beauty = TRUE;
+}
+
+
+static void copyData(ModifierData *md, ModifierData *target)
+{
+	TriangulateModifierData *smd = (TriangulateModifierData *) md;
+	TriangulateModifierData *tsmd = (TriangulateModifierData *) target;
+
+	*tsmd = *smd;
+}
+
+static DerivedMesh *applyModifierEM(ModifierData *md,
+                                    Object *UNUSED(ob),
+                                    struct BMEditMesh *UNUSED(em),
+                                    DerivedMesh *dm)
+{
+	TriangulateModifierData *tmd = (TriangulateModifierData *)md;
+	DerivedMesh *result;
+	if (!(result = triangulate(dm, tmd->beauty))) {
+		return dm;
+	}
+
+	return result;
+}
+
+static DerivedMesh *applyModifier(ModifierData *md,
+                                  Object *UNUSED(ob),
+                                  DerivedMesh *dm,
+                                  ModifierApplyFlag UNUSED(flag))
+{
+	TriangulateModifierData *tmd = (TriangulateModifierData *)md;
+	DerivedMesh *result;
+	if(!(result = triangulate(dm, tmd->beauty))) {
+		return dm;
+	}
+
+	return result;
+}
+
+ModifierTypeInfo modifierType_Triangulate = {
+	/* name */              "Triangulate",
+	/* structName */        "TriangulateModifierData",
+	/* structSize */        sizeof(TriangulateModifierData),
+	/* type */              eModifierTypeType_Constructive,
+	/* flags */             eModifierTypeFlag_AcceptsMesh |
+							eModifierTypeFlag_SupportsEditmode |
+							eModifierTypeFlag_SupportsMapping |
+							eModifierTypeFlag_EnableInEditmode |
+							eModifierTypeFlag_AcceptsCVs,
+
+	/* copyData */          copyData,
+	/* deformVerts */       NULL,
+	/* deformMatrices */    NULL,
+	/* deformVertsEM */     NULL,
+	/* deformMatricesEM */  NULL,
+	/* applyModifier */     applyModifier,
+	/* applyModifierEM */   applyModifierEM,
+	/* initData */          initData,
+	/* requiredDataMask */  NULL, //requiredDataMask,
+	/* freeData */          NULL,
+	/* isDisabled */        NULL,
+	/* updateDepgraph */    NULL,
+	/* dependsOnTime */     NULL,
+	/* dependsOnNormals */	NULL,
+	/* foreachObjectLink */ NULL,
+	/* foreachIDLink */     NULL,
+};
diff --git a/source/blender/modifiers/intern/MOD_util.c b/source/blender/modifiers/intern/MOD_util.c
index 3b769a30994..a27d5e5e03b 100644
--- a/source/blender/modifiers/intern/MOD_util.c
+++ b/source/blender/modifiers/intern/MOD_util.c
@@ -278,5 +278,6 @@ void modifier_type_init(ModifierTypeInfo *types[])
 	INIT_TYPE(Remesh);
 	INIT_TYPE(Skin);
 	INIT_TYPE(LaplacianSmooth);
+	INIT_TYPE(Triangulate);
 #undef INIT_TYPE
 }