Patch #5629 - Mirror modifier axis' to be toggleable

This patch makes the X, Y and Z axes of the mirror modifier individually
toggleable, so it is possible to mirror in more than one direction with a
single modifier.

Thanks to Juho Vepsäläinen (bebraw) for the patch!

NOTE: BLENDER_SUBVERSION has been incremented to support translation from old
      to new axis specification.

source/blender/blenkernel/BKE_blender.h

@@ -44,7 +44,7 @@ struct ListBase;
 struct MemFile;
 
 #define BLENDER_VERSION			243
-#define BLENDER_SUBVERSION		0
+#define BLENDER_SUBVERSION		1
 
 #define BLENDER_MINVERSION		240
 #define BLENDER_MINSUBVERSION	0

source/blender/blenkernel/intern/modifier.c

@@ -1240,11 +1240,12 @@ static void mirrorModifier_copyData(ModifierData *md, ModifierData *target)
 	tmmd->tolerance = mmd->tolerance;
 }
 
-static DerivedMesh *mirrorModifier__doMirror(MirrorModifierData *mmd,
-                                             DerivedMesh *dm,
-                                             int initFlags)
+static DerivedMesh *doMirrorOnAxis(MirrorModifierData *mmd,
+						   DerivedMesh *dm,
+						   int initFlags,
+						   int axis)
 {
-	int i, axis = mmd->axis;
+	int i;
 	float tolerance = mmd->tolerance;
 	DerivedMesh *result;
 	int numVerts, numEdges, numFaces;
@@ -1381,6 +1382,30 @@ static DerivedMesh *mirrorModifier__doMirror(MirrorModifierData *mmd,
 	return result;
 }
 
+static DerivedMesh *mirrorModifier__doMirror(MirrorModifierData *mmd,
+                                             DerivedMesh *dm,
+                                             int initFlags)
+{
+	DerivedMesh *result = dm;
+
+	/* check which axes have been toggled and mirror accordingly */
+	if(mmd->flag & MOD_MIR_AXIS_X) {
+		result = doMirrorOnAxis(mmd, result, initFlags, 0);
+	}
+	if(mmd->flag & MOD_MIR_AXIS_Y) {
+		DerivedMesh *tmp = result;
+		result = doMirrorOnAxis(mmd, result, initFlags, 1);
+		if(tmp != dm) tmp->release(tmp); /* free intermediate results */
+	}
+	if(mmd->flag & MOD_MIR_AXIS_Z) {
+		DerivedMesh *tmp = result;
+		result = doMirrorOnAxis(mmd, result, initFlags, 2);
+		if(tmp != dm) tmp->release(tmp); /* free intermediate results */
+	}
+
+	return result;
+}
+
 static DerivedMesh *mirrorModifier_applyModifier(
                  ModifierData *md, Object *ob, DerivedMesh *derivedData,
                  int useRenderParams, int isFinalCalc)

source/blender/blenloader/intern/readfile.c

@@ -6389,6 +6389,32 @@ static void do_versions(FileData *fd, Library *lib, Main *main)
 					unique_vertexgroup_name(curdef, ob);
 				}
 			}
+
+			if(main->versionfile < 243 || main->subversionfile < 1) {
+				ModifierData *md;
+
+				/* translate old mirror modifier axis values to new flags */
+				for (md=ob->modifiers.first; md; md=md->next) {
+					if (md->type==eModifierType_Mirror) {
+						MirrorModifierData *mmd = (MirrorModifierData*) md;
+
+						switch(mmd->axis)
+						{
+						case 0:
+							mmd->flag |= MOD_MIR_AXIS_X;
+							break;
+						case 1:
+							mmd->flag |= MOD_MIR_AXIS_Y;
+							break;
+						case 2:
+							mmd->flag |= MOD_MIR_AXIS_Z;
+							break;
+						}
+
+						mmd->axis = 0;
+					}
+				}
+			}
 		}
 	}
 

source/blender/makesdna/DNA_modifier_types.h

@@ -162,6 +162,9 @@ typedef struct MirrorModifierData {
 #define MOD_MIR_CLIPPING	1<<0
 #define MOD_MIR_MIRROR_U	1<<1
 #define MOD_MIR_MIRROR_V	1<<2
+#define MOD_MIR_AXIS_X		1<<3
+#define MOD_MIR_AXIS_Y		1<<4
+#define MOD_MIR_AXIS_Z		1<<5
 
 typedef struct EdgeSplitModifierData {
 	ModifierData modifier;

source/blender/src/buttons_editing.c

@@ -1681,9 +1681,9 @@ static void draw_modifier(uiBlock *block, Object *ob, ModifierData *md, int *xco
 		} else if (md->type==eModifierType_Mirror) {
 			MirrorModifierData *mmd = (MirrorModifierData*) md;
 			uiDefButF(block, NUM, B_MODIFIER_RECALC, "Merge Limit:", lx, (cy-=19), buttonWidth,19, &mmd->tolerance, 0.0, 1.0, 10, 10, "Distance from axis within which mirrored vertices are merged");
-			uiDefButS(block, ROW, B_MODIFIER_RECALC, "X",	lx, (cy-=19), 20,19, &mmd->axis, 1, 0, 0, 0, "Specify the axis to mirror about");
-			uiDefButS(block, ROW, B_MODIFIER_RECALC, "Y",	lx+20, cy, 20,19, &mmd->axis, 1, 1, 0, 0, "Specify the axis to mirror about");
-			uiDefButS(block, ROW, B_MODIFIER_RECALC, "Z",	lx+40, cy, 20,19, &mmd->axis, 1, 2, 0, 0, "Specify the axis to mirror about");
+			uiDefButBitS(block, TOG, MOD_MIR_AXIS_X, B_MODIFIER_RECALC, "X",	lx,(cy-=19),20,19, &mmd->flag, 0, 0, 0, 0, "Enable X axis mirror");
+			uiDefButBitS(block, TOG, MOD_MIR_AXIS_Y, B_MODIFIER_RECALC, "Y",	lx+20,cy,20,19,    &mmd->flag, 0, 0, 0, 0, "Enable Y axis mirror");
+			uiDefButBitS(block, TOG, MOD_MIR_AXIS_Z, B_MODIFIER_RECALC, "Z",	lx+40,cy,20,19,    &mmd->flag, 0, 0, 0, 0, "Enable Z axis mirror");
 			uiDefButBitS(block, TOG, MOD_MIR_CLIPPING, B_MODIFIER_RECALC, "Do Clipping",	lx+60, cy, buttonWidth-60,19, &mmd->flag, 1, 2, 0, 0, "Prevents during Transform vertices to go through Mirror");
 			uiDefButBitS(block, TOG, MOD_MIR_MIRROR_U, B_MODIFIER_RECALC,
 			             "Mirror U",