_Finally_ got the conversion from old multires files to the new kind working. Still some cleanups to do, and a couple of performance fixes, but it works OK now.

3 files changed, 368 insertions, 5 deletions

diff --git a/source/blender/blenkernel/BKE_multires.h b/source/blender/blenkernel/BKE_multires.h
index 91417591d98..3273c484a33 100644
--- a/source/blender/blenkernel/BKE_multires.h
+++ b/source/blender/blenkernel/BKE_multires.h
@@ -126,6 +126,8 @@ typedef struct MultiresDisplacer {
 	int x, y, ax, ay;
 } MultiresDisplacer;
 
+
+void multires_load_old(struct DerivedMesh *, struct Multires *);
 void multires_force_update(struct Object *ob);
 
 struct DerivedMesh *multires_dm_create_from_derived(struct MultiresModifierData*, struct DerivedMesh*,
diff --git a/source/blender/blenkernel/intern/multires.c b/source/blender/blenkernel/intern/multires.c
index 8f23c8f60fa..24a42f7f838 100644
--- a/source/blender/blenkernel/intern/multires.c
+++ b/source/blender/blenkernel/intern/multires.c
@@ -817,6 +817,297 @@ static const int multires_quad_tot[] = {4, 9, 25, 81, 289, 1089, 4225, 16641, 66
 static const int multires_tri_tot[]  = {3, 7, 19, 61, 217, 817,  3169, 12481, 49537, 197377, 787969,  3148801, 12589057};
 static const int multires_side_tot[] = {2, 3, 5,  9,  17,  33,   65,   129,   257,   513,    1025,    2049,    4097};
 
+static void create_old_vert_face_map(ListBase **map, IndexNode **mem, const MultiresFace *mface,
+				     const int totvert, const int totface)
+{
+	int i,j;
+	IndexNode *node = NULL;
+	
+	(*map) = MEM_callocN(sizeof(ListBase) * totvert, "vert face map");
+	(*mem) = MEM_callocN(sizeof(IndexNode) * totface*4, "vert face map mem");
+	node = *mem;
+	
+	/* Find the users */
+	for(i = 0; i < totface; ++i){
+		for(j = 0; j < (mface[i].v[3]?4:3); ++j, ++node) {
+			node->index = i;
+			BLI_addtail(&(*map)[mface[i].v[j]], node);
+		}
+	}
+}
+
+static void create_old_vert_edge_map(ListBase **map, IndexNode **mem, const MultiresEdge *medge,
+				     const int totvert, const int totedge)
+{
+	int i,j;
+	IndexNode *node = NULL;
+	
+	(*map) = MEM_callocN(sizeof(ListBase) * totvert, "vert edge map");
+	(*mem) = MEM_callocN(sizeof(IndexNode) * totedge*2, "vert edge map mem");
+	node = *mem;
+	
+	/* Find the users */
+	for(i = 0; i < totedge; ++i){
+		for(j = 0; j < 2; ++j, ++node) {
+			node->index = i;
+			BLI_addtail(&(*map)[medge[i].v[j]], node);
+		}
+	}
+}
+
+static MultiresFace *find_old_face(ListBase *map, MultiresFace *faces, int v1, int v2, int v3, int v4)
+{
+	IndexNode *n1;
+	int v[4] = {v1, v2, v3, v4}, i, j;
+
+	for(n1 = map[v1].first; n1; n1 = n1->next) {
+		int fnd[4] = {0, 0, 0, 0};
+
+		for(i = 0; i < 4; ++i) {
+			for(j = 0; j < 4; ++j) {
+				if(v[i] == faces[n1->index].v[j])
+					fnd[i] = 1;
+			}
+		}
+
+		if(fnd[0] && fnd[1] && fnd[2] && fnd[3])
+			return &faces[n1->index];
+	}
+
+	return NULL;
+}
+
+static MultiresEdge *find_old_edge(ListBase *map, MultiresEdge *edges, int v1, int v2)
+{
+	IndexNode *n1, *n2;
+
+	for(n1 = map[v1].first; n1; n1 = n1->next) {
+		for(n2 = map[v2].first; n2; n2 = n2->next) {
+			if(n1->index == n2->index)
+				return &edges[n1->index];
+		}
+	}
+
+	return NULL;
+}
+
+static void multires_load_old_edges(ListBase **emap, MultiresLevel *lvl, int *vvmap, int dst, int v1, int v2, int mov)
+{
+	int emid = find_old_edge(emap[2], lvl->edges, v1, v2)->mid;
+	vvmap[dst + mov] = emid;
+
+	if(lvl->next->next) {
+		multires_load_old_edges(emap + 1, lvl->next, vvmap, dst + mov, v1, emid, mov / 2);
+		multires_load_old_edges(emap + 1, lvl->next, vvmap, dst + mov, v2, emid, -mov / 2);
+	}
+}
+
+static void multires_load_old_faces(ListBase **fmap, ListBase **emap, MultiresLevel *lvl, int *vvmap, int dst,
+				    int v1, int v2, int v3, int v4, int st2, int st3)
+{
+	int fmid;
+	int emid13, emid14, emid23, emid24;
+
+	if(lvl && lvl->next) {
+		fmid = find_old_face(fmap[1], lvl->faces, v1, v2, v3, v4)->mid;
+		vvmap[dst] = fmid;
+
+		emid13 = find_old_edge(emap[1], lvl->edges, v1, v3)->mid;
+		emid14 = find_old_edge(emap[1], lvl->edges, v1, v4)->mid;
+		emid23 = find_old_edge(emap[1], lvl->edges, v2, v3)->mid;
+		emid24 = find_old_edge(emap[1], lvl->edges, v2, v4)->mid;
+
+
+		multires_load_old_faces(fmap + 1, emap + 1, lvl->next, vvmap, dst + st2 * st3 + st3,
+					fmid, v2, emid23, emid24, st2, st3 / 2);
+
+		multires_load_old_faces(fmap + 1, emap + 1, lvl->next, vvmap, dst - st2 * st3 + st3,
+					emid14, emid24, fmid, v4, st2, st3 / 2);
+
+		multires_load_old_faces(fmap + 1, emap + 1, lvl->next, vvmap, dst + st2 * st3 - st3,
+					emid13, emid23, v3, fmid, st2, st3 / 2);
+
+		multires_load_old_faces(fmap + 1, emap + 1, lvl->next, vvmap, dst - st2 * st3 - st3,
+					v1, fmid, emid13, emid14, st2, st3 / 2);
+
+		if(lvl->next->next) {
+			multires_load_old_edges(emap, lvl->next, vvmap, dst, emid24, fmid, st3);
+			multires_load_old_edges(emap, lvl->next, vvmap, dst, emid13, fmid, -st3);
+			multires_load_old_edges(emap, lvl->next, vvmap, dst, emid14, fmid, -st2 * st3);
+			multires_load_old_edges(emap, lvl->next, vvmap, dst, emid23, fmid, st2 * st3);
+		}
+	}
+}
+
+void multires_load_old(DerivedMesh *dm, Multires *mr)
+{
+	MultiresLevel *lvl, *lvl1;
+	MVert *vsrc, *vdst;
+	int src, dst;
+	int totlvl = MultiresDM_get_totlvl(dm);
+	int st = multires_side_tot[totlvl - 2] - 1;
+	int extedgelen = multires_side_tot[totlvl - 1] - 2;
+	int *vvmap; // inorder for dst, map to src
+	int crossedgelen;
+	int i, j, s, x, totvert, tottri, totquad;
+
+	src = 0;
+	dst = 0;
+	vsrc = mr->verts;
+	vdst = CDDM_get_verts(dm);
+	totvert = dm->getNumVerts(dm);
+	vvmap = MEM_callocN(sizeof(int) * totvert, "multires vvmap");
+
+	lvl1 = mr->levels.first;
+	/* Load base verts */
+	for(i = 0; i < lvl1->totvert; ++i) {
+		vvmap[totvert - lvl1->totvert + i] = src;
+		++src;
+	}
+
+	/* Original edges */
+	dst = totvert - lvl1->totvert - extedgelen * lvl1->totedge;
+	for(i = 0; i < lvl1->totedge; ++i) {
+		int ldst = dst + extedgelen * i;
+		int lsrc = src;
+		lvl = lvl1->next;
+
+		for(j = 2; j <= mr->level_count; ++j) {
+			int base = multires_side_tot[totlvl - j] - 2;
+			int skip = multires_side_tot[totlvl - j + 1] - 1;
+			int st = multires_side_tot[j - 2] - 1;
+
+			for(x = 0; x < st; ++x)
+				vvmap[ldst + base + x * skip] = lsrc + st * i + x;
+
+			lsrc += lvl->totvert - lvl->prev->totvert;
+			lvl = lvl->next;
+		}
+	}
+
+	/* Center points */
+	dst = 0;
+	for(i = 0; i < lvl1->totface; ++i) {
+		int sides = lvl1->faces[i].v[3] ? 4 : 3;
+
+		vvmap[dst] = src + lvl1->totedge + i;
+		dst += 1 + sides * (st - 1) * st;
+	}
+
+
+	/* The rest is only for level 3 and up */
+	if(lvl1->next && lvl1->next->next) {
+		ListBase **fmap, **emap;
+		IndexNode **fmem, **emem;
+
+		/* Face edge cross */
+		tottri = totquad = 0;
+		crossedgelen = multires_side_tot[totlvl - 2] - 2;
+		dst = 0;
+		for(i = 0; i < lvl1->totface; ++i) {
+			int sides = lvl1->faces[i].v[3] ? 4 : 3;
+
+			lvl = lvl1->next->next;
+			++dst;
+
+			for(j = 3; j <= mr->level_count; ++j) {
+				int base = multires_side_tot[totlvl - j] - 2;
+				int skip = multires_side_tot[totlvl - j + 1] - 1;
+				int st = pow(2, j - 2);
+				int st2 = pow(2, j - 3);
+				int lsrc = lvl->prev->totvert;
+
+				/* Skip exterior edge verts */
+				lsrc += lvl1->totedge * st;
+
+				/* Skip earlier face edge crosses */
+				lsrc += st2 * (tottri * 3 + totquad * 4);
+
+				for(s = 0; s < sides; ++s) {
+					for(x = 0; x < st2; ++x) {
+						vvmap[dst + crossedgelen * (s + 1) - base - x * skip - 1] = lsrc;
+						++lsrc;
+					}
+				}
+
+				lvl = lvl->next;
+			}
+
+			dst += sides * (st - 1) * st;
+
+			if(sides == 4) ++totquad;
+			else ++tottri;
+
+		}
+
+		/* calculate vert to edge/face maps for each level */
+		fmap = MEM_callocN(sizeof(ListBase*) * mr->level_count, "multires fmap");
+		emap = MEM_callocN(sizeof(ListBase*) * mr->level_count, "multires emap");
+		fmem = MEM_callocN(sizeof(IndexNode*) * mr->level_count, "multires fmem");
+		emem = MEM_callocN(sizeof(IndexNode*) * mr->level_count, "multires emem");
+		lvl = lvl1;
+		for(i = 0; i < mr->level_count; ++i) {
+			create_old_vert_face_map(fmap + i, fmem + i, lvl->faces, lvl->totvert, lvl->totface);
+			create_old_vert_edge_map(emap + i, emem + i, lvl->edges, lvl->totvert, lvl->totedge);
+			lvl = lvl->next;
+		}
+
+		/* Interior face verts */
+		lvl = lvl1->next->next;
+		for(i = 3; i <= 3/*(mr->level_count*/; ++i) {
+			tottri = totquad = 0;
+			dst = 0;
+			for(j = 0; j < lvl1->totface; ++j) {
+				int sides = lvl1->faces[j].v[3] ? 4 : 3;
+				int ldst = dst + 1 + sides * (st - 1);
+
+				for(s = 0; s < sides; ++s) {
+					int st2 = multires_side_tot[totlvl - 2] - 2;
+					int st3 = multires_side_tot[totlvl - 3] - 2;
+					int st4 = st3 == 0 ? 1 : (st3 + 1) / 2;
+					int mid = ldst + st2 * st3 + st3;
+					int cv = lvl1->faces[j].v[s];
+					int nv = lvl1->faces[j].v[s == sides - 1 ? 0 : s + 1];
+					int pv = lvl1->faces[j].v[s == 0 ? sides - 1 : s - 1];
+
+					multires_load_old_faces(fmap, emap, lvl1->next, vvmap, mid,
+								vvmap[dst], cv,
+								find_old_edge(emap[0], lvl1->edges, pv, cv)->mid,
+								find_old_edge(emap[0], lvl1->edges, cv, nv)->mid,
+								st2, st4);
+
+					ldst += (st - 1) * (st - 1);
+				}
+
+
+				dst = ldst;
+				if(sides == 4) ++totquad;
+				else ++tottri;
+			}
+
+			lvl = lvl->next;
+		}
+
+		for(i = 0; i < mr->level_count; ++i) {
+			MEM_freeN(fmap[i]);
+			MEM_freeN(fmem[i]);
+			MEM_freeN(emap[i]);
+			MEM_freeN(emem[i]);
+		}
+
+		MEM_freeN(fmap);
+		MEM_freeN(emap);
+		MEM_freeN(fmem);
+		MEM_freeN(emem);
+	}
+
+	/* Transfer verts */
+	for(i = 0; i < totvert; ++i)
+		VecCopyf(vdst[i].co, vsrc[vvmap[i]].co);
+
+	MEM_freeN(vvmap);
+}
+
 int multiresModifier_switch_level(Object *ob, const int distance)
 {
 	ModifierData *md = NULL;
diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index 914bc39a0bd..c7893bcfaf0 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -115,6 +115,7 @@
 
 #include "BKE_action.h"
 #include "BKE_armature.h"
+#include "BKE_cdderivedmesh.h"
 #include "BKE_cloth.h"
 #include "BKE_colortools.h"
 #include "BKE_constraint.h"
@@ -132,6 +133,7 @@
 #include "BKE_main.h" // for Main
 #include "BKE_mesh.h" // for ME_ defines (patching)
 #include "BKE_modifier.h"
+#include "BKE_multires.h"
 #include "BKE_node.h" // for tree type defines
 #include "BKE_object.h"
 #include "BKE_particle.h"
@@ -2812,11 +2814,6 @@ static void direct_link_mesh(FileData *fd, Mesh *mesh)
 		if(mesh->mr->edge_creases)
 			mesh->mr->edge_creases= newdataadr(fd, mesh->mr->edge_creases);
 		
-		if(!mesh->mr->edge_flags)
-			mesh->mr->edge_flags= MEM_callocN(sizeof(short)*lvl->totedge, "Multires Edge Flags");
-		if(!mesh->mr->edge_creases)
-			mesh->mr->edge_creases= MEM_callocN(sizeof(char)*lvl->totedge, "Multires Edge Creases");
-
 		mesh->mr->verts = newdataadr(fd, mesh->mr->verts);
 			
 		for(; lvl; lvl= lvl->next) {
@@ -7746,6 +7743,79 @@ static void do_versions(FileData *fd, Library *lib, Main *main)
 		}
 	}
 
+	/* TODO: should be moved into one of the version blocks once this branch moves to trunk and we can
+	   bump the version (or sub-version.) */
+	{
+		Object *ob;
+		int i;
+
+		for(ob = main->object.first; ob; ob = ob->id.next) {
+
+			if(ob->type == OB_MESH) {
+				Mesh *me = newlibadr(fd, lib, ob->data);
+				void *olddata = ob->data;
+				ob->data = me;
+
+				if(me && me->mr) {
+					MultiresLevel *lvl;
+					ModifierData *md;
+					MultiresModifierData *mmd;
+					DerivedMesh *dm, *orig;
+
+					/* Load original level into the mesh */
+					lvl = me->mr->levels.first;
+					CustomData_free_layers(&me->vdata, CD_MVERT, lvl->totvert);
+					CustomData_free_layers(&me->edata, CD_MEDGE, lvl->totedge);
+					CustomData_free_layers(&me->fdata, CD_MFACE, lvl->totface);
+					me->totvert = lvl->totvert;
+					me->totedge = lvl->totedge;
+					me->totface = lvl->totface;
+					me->mvert = CustomData_add_layer(&me->vdata, CD_MVERT, CD_CALLOC, NULL, me->totvert);
+					me->medge = CustomData_add_layer(&me->edata, CD_MEDGE, CD_CALLOC, NULL, me->totedge);
+					me->mface = CustomData_add_layer(&me->fdata, CD_MFACE, CD_CALLOC, NULL, me->totface);
+					memcpy(me->mvert, me->mr->verts, sizeof(MVert) * me->totvert);
+					for(i = 0; i < me->totedge; ++i) {
+						me->medge[i].v1 = lvl->edges[i].v[0];
+						me->medge[i].v2 = lvl->edges[i].v[1];
+					}
+					for(i = 0; i < me->totface; ++i) {
+						me->mface[i].v1 = lvl->faces[i].v[0];
+						me->mface[i].v2 = lvl->faces[i].v[1];
+						me->mface[i].v3 = lvl->faces[i].v[2];
+						me->mface[i].v4 = lvl->faces[i].v[3];
+					}
+
+					/* Add a multires modifier to the object */
+					md = ob->modifiers.first;
+					while(md && modifierType_getInfo(md->type)->type == eModifierTypeType_OnlyDeform)
+						md = md->next;				
+					mmd = (MultiresModifierData*)modifier_new(eModifierType_Multires);
+					BLI_insertlinkbefore(&ob->modifiers, md, mmd);
+
+					for(i = 1; i < me->mr->level_count; ++i)
+						multiresModifier_subdivide(mmd, ob);
+
+					mmd->lvl = mmd->totlvl;
+					orig = CDDM_from_mesh(me, NULL);
+					dm = multires_dm_create_from_derived(mmd, orig, me, 0, 0);
+					
+					multires_load_old(dm, me->mr);
+
+					*MultiresDM_get_flags(dm) |= MULTIRES_DM_UPDATE_ALWAYS;
+					dm->release(dm);
+					orig->release(orig);
+
+					/* Remove the old multires */
+					multires_free(me->mr);
+					me->mr = NULL;
+				}
+
+				ob->data = olddata;
+			}
+		}
+	}
+
+
 	/* WATCH IT!!!: pointers from libdata have not been converted yet here! */
 	/* WATCH IT 2!: Userdef struct init has to be in src/usiblender.c! */