Write .blend file: refactor & fixes re ID block itself.

Factorized writing of ID block's data (so far, only IDProps) into own helper func.
This also fixes missing IDProp (aka custom data) saving from GreasePencil and Library
datablocks (and add comment about why we do not save WM IDProps).

Finaly, it ensures all ID-related data are written immediately after the ID itself
(was not the case for all data types previously, some were writting their own data
before IDProps). This is not a fix (.blend file format does not enforce any order
on sub-data of datablocks, they only have to be after datablock struct itself in file),
but makes things more consistent.

1 files changed, 120 insertions, 115 deletions

diff --git a/source/blender/blenloader/intern/writefile.c b/source/blender/blenloader/intern/writefile.c
index 124b1efddac..327b7b5aed4 100644
--- a/source/blender/blenloader/intern/writefile.c
+++ b/source/blender/blenloader/intern/writefile.c
@@ -588,6 +588,14 @@ void IDP_WriteProperty(IDProperty *prop, void *wd)
 	IDP_WriteProperty_OnlyData(prop, wd);
 }
 
+static void write_iddata(void *wd, ID *id)
+{
+	/* ID_WM's id->properties are considered runtime only, and never written in .blend file. */
+	if (id->properties && !ELEM(GS(id->name), ID_WM)) {
+		IDP_WriteProperty(id->properties, wd);
+	}
+}
+
 static void write_previews(WriteData *wd, PreviewImage *prv)
 {
 	/* Never write previews when doing memsave (i.e. undo/redo)! */
@@ -716,8 +724,8 @@ static void write_actions(WriteData *wd, ListBase *idbase)
 	for (act=idbase->first; act; act= act->id.next) {
 		if (act->id.us>0 || wd->current) {
 			writestruct(wd, ID_AC, "bAction", 1, act);
-			if (act->id.properties) IDP_WriteProperty(act->id.properties, wd);
-			
+			write_iddata(wd, &act->id);
+
 			write_fcurves(wd, &act->curves);
 			
 			for (grp=act->groups.first; grp; grp=grp->next) {
@@ -1155,7 +1163,8 @@ static void write_particlesettings(WriteData *wd, ListBase *idbase)
 		if (part->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_PA, "ParticleSettings", 1, part);
-			if (part->id.properties) IDP_WriteProperty(part->id.properties, wd);
+			write_iddata(wd, &part->id);
+
 			if (part->adt) write_animdata(wd, part->adt);
 			writestruct(wd, DATA, "PartDeflect", 1, part->pd);
 			writestruct(wd, DATA, "PartDeflect", 1, part->pd2);
@@ -1668,11 +1677,8 @@ static void write_objects(WriteData *wd, ListBase *idbase)
 		if (ob->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_OB, "Object", 1, ob);
-			
-			/* Write ID Properties -- and copy this comment EXACTLY for easy finding
-			 * of library blocks that implement this.*/
-			if (ob->id.properties) IDP_WriteProperty(ob->id.properties, wd);
-			
+			write_iddata(wd, &ob->id);
+
 			if (ob->adt) write_animdata(wd, ob->adt);
 			
 			/* direct data */
@@ -1743,7 +1749,7 @@ static void write_vfonts(WriteData *wd, ListBase *idbase)
 		if (vf->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_VF, "VFont", 1, vf);
-			if (vf->id.properties) IDP_WriteProperty(vf->id.properties, wd);
+			write_iddata(wd, &vf->id);
 
 			/* direct data */
 
@@ -1769,8 +1775,8 @@ static void write_keys(WriteData *wd, ListBase *idbase)
 		if (key->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_KE, "Key", 1, key);
-			if (key->id.properties) IDP_WriteProperty(key->id.properties, wd);
-			
+			write_iddata(wd, &key->id);
+
 			if (key->adt) write_animdata(wd, key->adt);
 			
 			/* direct data */
@@ -1797,8 +1803,8 @@ static void write_cameras(WriteData *wd, ListBase *idbase)
 		if (cam->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_CA, "Camera", 1, cam);
-			if (cam->id.properties) IDP_WriteProperty(cam->id.properties, wd);
-			
+			write_iddata(wd, &cam->id);
+
 			if (cam->adt) write_animdata(wd, cam->adt);
 		}
 
@@ -1816,7 +1822,7 @@ static void write_mballs(WriteData *wd, ListBase *idbase)
 		if (mb->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_MB, "MetaBall", 1, mb);
-			if (mb->id.properties) IDP_WriteProperty(mb->id.properties, wd);
+			write_iddata(wd, &mb->id);
 
 			/* direct data */
 			writedata(wd, DATA, sizeof(void *)*mb->totcol, mb->mat);
@@ -1842,10 +1848,10 @@ static void write_curves(WriteData *wd, ListBase *idbase)
 		if (cu->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_CU, "Curve", 1, cu);
-			
+			write_iddata(wd, &cu->id);
+
 			/* direct data */
 			writedata(wd, DATA, sizeof(void *)*cu->totcol, cu->mat);
-			if (cu->id.properties) IDP_WriteProperty(cu->id.properties, wd);
 			if (cu->adt) write_animdata(wd, cu->adt);
 			
 			if (cu->vfont) {
@@ -2037,9 +2043,9 @@ static void write_meshes(WriteData *wd, ListBase *idbase)
 				CustomData_file_write_prepare(&mesh->pdata, &players, players_buff, ARRAY_SIZE(players_buff));
 
 				writestruct_at_address(wd, ID_ME, "Mesh", 1, old_mesh, mesh);
+				write_iddata(wd, &mesh->id);
 
 				/* direct data */
-				if (mesh->id.properties) IDP_WriteProperty(mesh->id.properties, wd);
 				if (mesh->adt) write_animdata(wd, mesh->adt);
 
 				writedata(wd, DATA, sizeof(void *)*mesh->totcol, mesh->mat);
@@ -2095,9 +2101,9 @@ static void write_meshes(WriteData *wd, ListBase *idbase)
 #endif
 
 				writestruct_at_address(wd, ID_ME, "Mesh", 1, old_mesh, mesh);
+				write_iddata(wd, &mesh->id);
 
 				/* direct data */
-				if (mesh->id.properties) IDP_WriteProperty(mesh->id.properties, wd);
 				if (mesh->adt) write_animdata(wd, mesh->adt);
 
 				writedata(wd, DATA, sizeof(void *)*mesh->totcol, mesh->mat);
@@ -2150,8 +2156,8 @@ static void write_lattices(WriteData *wd, ListBase *idbase)
 		if (lt->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_LT, "Lattice", 1, lt);
-			if (lt->id.properties) IDP_WriteProperty(lt->id.properties, wd);
-			
+			write_iddata(wd, &lt->id);
+
 			/* write animdata */
 			if (lt->adt) write_animdata(wd, lt->adt);
 			
@@ -2184,7 +2190,7 @@ static void write_images(WriteData *wd, ListBase *idbase)
 
 			/* write LibData */
 			writestruct(wd, ID_IM, "Image", 1, ima);
-			if (ima->id.properties) IDP_WriteProperty(ima->id.properties, wd);
+			write_iddata(wd, &ima->id);
 
 			for (imapf = ima->packedfiles.first; imapf; imapf = imapf->next) {
 				writestruct(wd, DATA, "ImagePackedFile", 1, imapf);
@@ -2218,7 +2224,7 @@ static void write_textures(WriteData *wd, ListBase *idbase)
 		if (tex->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_TE, "Tex", 1, tex);
-			if (tex->id.properties) IDP_WriteProperty(tex->id.properties, wd);
+			write_iddata(wd, &tex->id);
 
 			if (tex->adt) write_animdata(wd, tex->adt);
 
@@ -2258,13 +2264,8 @@ static void write_materials(WriteData *wd, ListBase *idbase)
 		if (ma->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_MA, "Material", 1, ma);
-			
-			/* Write ID Properties -- and copy this comment EXACTLY for easy finding
-			 * of library blocks that implement this.*/
-			/* manually set head group property to IDP_GROUP, just in case it hadn't been
-			 * set yet :) */
-			if (ma->id.properties) IDP_WriteProperty(ma->id.properties, wd);
-			
+			write_iddata(wd, &ma->id);
+
 			if (ma->adt) write_animdata(wd, ma->adt);
 
 			for (a=0; a<MAX_MTEX; a++) {
@@ -2296,8 +2297,8 @@ static void write_worlds(WriteData *wd, ListBase *idbase)
 		if (wrld->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_WO, "World", 1, wrld);
-			if (wrld->id.properties) IDP_WriteProperty(wrld->id.properties, wd);
-			
+			write_iddata(wd, &wrld->id);
+
 			if (wrld->adt) write_animdata(wd, wrld->adt);
 			
 			for (a=0; a<MAX_MTEX; a++) {
@@ -2326,8 +2327,8 @@ static void write_lamps(WriteData *wd, ListBase *idbase)
 		if (la->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_LA, "Lamp", 1, la);
-			if (la->id.properties) IDP_WriteProperty(la->id.properties, wd);
-			
+			write_iddata(wd, &la->id);
+
 			if (la->adt) write_animdata(wd, la->adt);
 			
 			/* direct data */
@@ -2411,8 +2412,8 @@ static void write_scenes(WriteData *wd, ListBase *scebase)
 	while (sce) {
 		/* write LibData */
 		writestruct(wd, ID_SCE, "Scene", 1, sce);
-		if (sce->id.properties) IDP_WriteProperty(sce->id.properties, wd);
-		
+		write_iddata(wd, &sce->id);
+
 		if (sce->adt) write_animdata(wd, sce->adt);
 		write_keyingsets(wd, &sce->keyingsets);
 		
@@ -2593,7 +2594,8 @@ static void write_gpencils(WriteData *wd, ListBase *lb)
 		if (gpd->id.us>0 || wd->current) {
 			/* write gpd data block to file */
 			writestruct(wd, ID_GD, "bGPdata", 1, gpd);
-			
+			write_iddata(wd, &gpd->id);
+
 			if (gpd->adt) write_animdata(wd, gpd->adt);
 			
 			/* write grease-pencil layers to file */
@@ -2622,7 +2624,8 @@ static void write_windowmanagers(WriteData *wd, ListBase *lb)
 	
 	for (wm= lb->first; wm; wm= wm->id.next) {
 		writestruct(wd, ID_WM, "wmWindowManager", 1, wm);
-		
+		write_iddata(wd, &wm->id);
+
 		for (win= wm->windows.first; win; win= win->next) {
 			writestruct(wd, DATA, "wmWindow", 1, win);
 			writestruct(wd, DATA, "Stereo3dFormat", 1, win->stereo3d_format);
@@ -2722,9 +2725,8 @@ static void write_screens(WriteData *wd, ListBase *scrbase)
 		/* write LibData */
 		/* in 2.50+ files, the file identifier for screens is patched, forward compatibility */
 		writestruct(wd, ID_SCRN, "Screen", 1, sc);
-		if (sc->id.properties) 
-			IDP_WriteProperty(sc->id.properties, wd);
-		
+		write_iddata(wd, &sc->id);
+
 		/* direct data */
 		for (sv= sc->vertbase.first; sv; sv= sv->next)
 			writestruct(wd, DATA, "ScrVert", 1, sv);
@@ -2879,63 +2881,6 @@ static void write_screens(WriteData *wd, ListBase *scrbase)
 	mywrite(wd, MYWRITE_FLUSH, 0);
 }
 
-static void write_libraries(WriteData *wd, Main *main)
-{
-	ListBase *lbarray[MAX_LIBARRAY];
-	ID *id;
-	int a, tot;
-	bool found_one;
-
-	for (; main; main= main->next) {
-
-		a=tot= set_listbasepointers(main, lbarray);
-
-		/* test: is lib being used */
-		if (main->curlib && main->curlib->packedfile)
-			found_one = true;
-		else {
-			found_one = false;
-			while (tot--) {
-				for (id= lbarray[tot]->first; id; id= id->next) {
-					if (id->us > 0 && (id->tag & LIB_TAG_EXTERN)) {
-						found_one = true;
-						break;
-					}
-				}
-				if (found_one) break;
-			}
-		}
-		
-		/* to be able to restore quit.blend and temp saves, the packed blend has to be in undo buffers... */
-		/* XXX needs rethink, just like save UI in undo files now - would be nice to append things only for the]
-		 * quit.blend and temp saves */
-		if (found_one) {
-			writestruct(wd, ID_LI, "Library", 1, main->curlib);
-
-			if (main->curlib->packedfile) {
-				PackedFile *pf = main->curlib->packedfile;
-				writestruct(wd, DATA, "PackedFile", 1, pf);
-				writedata(wd, DATA, pf->size, pf->data);
-				if (wd->current == NULL)
-					printf("write packed .blend: %s\n", main->curlib->name);
-			}
-			
-			while (a--) {
-				for (id= lbarray[a]->first; id; id= id->next) {
-					if (id->us > 0 && (id->tag & LIB_TAG_EXTERN)) {
-						if (!BKE_idcode_is_linkable(GS(id->name))) {
-							printf("ERROR: write file: datablock '%s' from lib '%s' is not linkable "
-							       "but is flagged as directly linked", id->name, main->curlib->filepath);
-							BLI_assert(0);
-						}
-						writestruct(wd, ID_ID, "ID", 1, id);
-					}
-				}
-			}
-		}
-	}
-}
-
 static void write_bone(WriteData *wd, Bone *bone)
 {
 	Bone*	cbone;
@@ -2968,7 +2913,7 @@ static void write_armatures(WriteData *wd, ListBase *idbase)
 	while (arm) {
 		if (arm->id.us>0 || wd->current) {
 			writestruct(wd, ID_AR, "bArmature", 1, arm);
-			if (arm->id.properties) IDP_WriteProperty(arm->id.properties, wd);
+			write_iddata(wd, &arm->id);
 
 			if (arm->adt) write_animdata(wd, arm->adt);
 
@@ -2997,8 +2942,9 @@ static void write_texts(WriteData *wd, ListBase *idbase)
 
 		/* write LibData */
 		writestruct(wd, ID_TXT, "Text", 1, text);
+		write_iddata(wd, &text->id);
+
 		if (text->name) writedata(wd, DATA, strlen(text->name)+1, text->name);
-		if (text->id.properties) IDP_WriteProperty(text->id.properties, wd);
 
 		if (!(text->flags & TXT_ISEXT)) {
 			/* now write the text data, in two steps for optimization in the readfunction */
@@ -3032,7 +2978,7 @@ static void write_speakers(WriteData *wd, ListBase *idbase)
 		if (spk->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_SPK, "Speaker", 1, spk);
-			if (spk->id.properties) IDP_WriteProperty(spk->id.properties, wd);
+			write_iddata(wd, &spk->id);
 
 			if (spk->adt) write_animdata(wd, spk->adt);
 		}
@@ -3051,7 +2997,7 @@ static void write_sounds(WriteData *wd, ListBase *idbase)
 		if (sound->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_SO, "bSound", 1, sound);
-			if (sound->id.properties) IDP_WriteProperty(sound->id.properties, wd);
+			write_iddata(wd, &sound->id);
 
 			if (sound->packedfile) {
 				pf = sound->packedfile;
@@ -3075,7 +3021,7 @@ static void write_groups(WriteData *wd, ListBase *idbase)
 		if (group->id.us>0 || wd->current) {
 			/* write LibData */
 			writestruct(wd, ID_GR, "Group", 1, group);
-			if (group->id.properties) IDP_WriteProperty(group->id.properties, wd);
+			write_iddata(wd, &group->id);
 
 			write_previews(wd, group->preview);
 
@@ -3095,11 +3041,11 @@ static void write_nodetrees(WriteData *wd, ListBase *idbase)
 	for (ntree=idbase->first; ntree; ntree= ntree->id.next) {
 		if (ntree->id.us>0 || wd->current) {
 			writestruct(wd, ID_NT, "bNodeTree", 1, ntree);
+			/* Note that trees directly used by other IDs (materials etc.) are not 'real' ID, they cannot
+			 * be linked, etc., so we write actual id data here only, for 'real' ID trees. */
+			write_iddata(wd, &ntree->id);
+
 			write_nodetree(wd, ntree);
-			
-			if (ntree->id.properties) IDP_WriteProperty(ntree->id.properties, wd);
-			
-			if (ntree->adt) write_animdata(wd, ntree->adt);
 		}
 	}
 }
@@ -3178,8 +3124,8 @@ static void write_brushes(WriteData *wd, ListBase *idbase)
 	for (brush=idbase->first; brush; brush= brush->id.next) {
 		if (brush->id.us>0 || wd->current) {
 			writestruct(wd, ID_BR, "Brush", 1, brush);
-			if (brush->id.properties) IDP_WriteProperty(brush->id.properties, wd);
-			
+			write_iddata(wd, &brush->id);
+
 			if (brush->curve)
 				write_curvemapping(wd, brush->curve);
 			if (brush->gradient)
@@ -3196,7 +3142,7 @@ static void write_palettes(WriteData *wd, ListBase *idbase)
 		if (palette->id.us > 0 || wd->current) {
 			PaletteColor *color;
 			writestruct(wd, ID_PAL, "Palette", 1, palette);
-			if (palette->id.properties) IDP_WriteProperty(palette->id.properties, wd);
+			write_iddata(wd, &palette->id);
 
 			for (color = palette->colors.first; color; color= color->next)
 				writestruct(wd, DATA, "PaletteColor", 1, color);
@@ -3211,9 +3157,9 @@ static void write_paintcurves(WriteData *wd, ListBase *idbase)
 	for (pc = idbase->first; pc; pc = pc->id.next) {
 		if (pc->id.us > 0 || wd->current) {
 			writestruct(wd, ID_PC, "PaintCurve", 1, pc);
+			write_iddata(wd, &pc->id);
 
 			writestruct(wd, DATA, "PaintCurvePoint", pc->tot_points, pc->points);
-			if (pc->id.properties) IDP_WriteProperty(pc->id.properties, wd);
 		}
 	}
 }
@@ -3263,10 +3209,9 @@ static void write_movieclips(WriteData *wd, ListBase *idbase)
 		if (clip->id.us>0 || wd->current) {
 			MovieTracking *tracking= &clip->tracking;
 			MovieTrackingObject *object;
-			writestruct(wd, ID_MC, "MovieClip", 1, clip);
 
-			if (clip->id.properties)
-				IDP_WriteProperty(clip->id.properties, wd);
+			writestruct(wd, ID_MC, "MovieClip", 1, clip);
+			write_iddata(wd, &clip->id);
 
 			if (clip->adt)
 				write_animdata(wd, clip->adt);
@@ -3304,6 +3249,7 @@ static void write_masks(WriteData *wd, ListBase *idbase)
 			MaskLayer *masklay;
 
 			writestruct(wd, ID_MSK, "Mask", 1, mask);
+			write_iddata(wd, &mask->id);
 
 			if (mask->adt)
 				write_animdata(wd, mask->adt);
@@ -3609,8 +3555,8 @@ static void write_linestyles(WriteData *wd, ListBase *idbase)
 	for (linestyle = idbase->first; linestyle; linestyle = linestyle->id.next) {
 		if (linestyle->id.us>0 || wd->current) {
 			writestruct(wd, ID_LS, "FreestyleLineStyle", 1, linestyle);
-			if (linestyle->id.properties)
-				IDP_WriteProperty(linestyle->id.properties, wd);
+			write_iddata(wd, &linestyle->id);
+
 			if (linestyle->adt)
 				write_animdata(wd, linestyle->adt);
 			write_linestyle_color_modifiers(wd, &linestyle->color_modifiers);
@@ -3628,6 +3574,65 @@ static void write_linestyles(WriteData *wd, ListBase *idbase)
 	}
 }
 
+/* Keep it last of write_foodata functions. */
+static void write_libraries(WriteData *wd, Main *main)
+{
+	ListBase *lbarray[MAX_LIBARRAY];
+	ID *id;
+	int a, tot;
+	bool found_one;
+
+	for (; main; main= main->next) {
+
+		a=tot= set_listbasepointers(main, lbarray);
+
+		/* test: is lib being used */
+		if (main->curlib && main->curlib->packedfile)
+			found_one = true;
+		else {
+			found_one = false;
+			while (tot--) {
+				for (id= lbarray[tot]->first; id; id= id->next) {
+					if (id->us > 0 && (id->tag & LIB_TAG_EXTERN)) {
+						found_one = true;
+						break;
+					}
+				}
+				if (found_one) break;
+			}
+		}
+
+		/* to be able to restore quit.blend and temp saves, the packed blend has to be in undo buffers... */
+		/* XXX needs rethink, just like save UI in undo files now - would be nice to append things only for the]
+		 * quit.blend and temp saves */
+		if (found_one) {
+			writestruct(wd, ID_LI, "Library", 1, main->curlib);
+			write_iddata(wd, &main->curlib->id);
+
+			if (main->curlib->packedfile) {
+				PackedFile *pf = main->curlib->packedfile;
+				writestruct(wd, DATA, "PackedFile", 1, pf);
+				writedata(wd, DATA, pf->size, pf->data);
+				if (wd->current == NULL)
+					printf("write packed .blend: %s\n", main->curlib->name);
+			}
+
+			while (a--) {
+				for (id= lbarray[a]->first; id; id= id->next) {
+					if (id->us > 0 && (id->tag & LIB_TAG_EXTERN)) {
+						if (!BKE_idcode_is_linkable(GS(id->name))) {
+							printf("ERROR: write file: datablock '%s' from lib '%s' is not linkable "
+							       "but is flagged as directly linked", id->name, main->curlib->filepath);
+							BLI_assert(0);
+						}
+						writestruct(wd, ID_ID, "ID", 1, id);
+					}
+				}
+			}
+		}
+	}
+}
+
 /* context is usually defined by WM, two cases where no WM is available:
  * - for forward compatibility, curscreen has to be saved
  * - for undofile, curscene needs to be saved */