Bake from multires mesh

=======================

Added option to baked named "Bake From Multires" which is avaliable for
normals baking and displacement baking.

If this option is enabled, then no additional hi-res meshes and render
structures would be created . This saves plenty of memory and meshes
with millions of faces could be successfully baked in few minutes.

Baking happens from highest level against viewport subdivision level,
so workflow is following:
  - Set viewport level to level at which texture would be applied
    during final rendering.
  - Choose Displacement/Normals baking.
  - Enable "Bake From Multires" option.
  - You're ready to bake.

Displacement baker had aditional option named "Low Resolution Mesh".
This option is used to set if you want texture for realtime (games)
usage.

Internally it does the following:
  - If it's disabled, displacement is calculated from subdivided
    viewport level, so texture looks "smooth" (it's how default
    baked works).
  - If it's enabled, dispalcement is calculated against unsubdivided
    viewport levels. This leads to "scales". This isn;t useful for
    offline renders much, but very useful for creating game textures.

Special thanks to Morten Mikkelsen (aka sparky) for all mathematics
and other work he've done fr this patch!

1 files changed, 1213 insertions, 56 deletions

diff --git a/source/blender/editors/object/object_bake.c b/source/blender/editors/object/object_bake.c
index b513bab3924..af815988935 100644
--- a/source/blender/editors/object/object_bake.c
+++ b/source/blender/editors/object/object_bake.c
@@ -22,7 +22,8 @@
  *
  * The Original Code is: all of this file.
  *
- * Contributor(s): none yet.
+ * Contributor(s): Morten Mikkelsen,
+ *                 Sergey Sharybin
  *
  * ***** END GPL LICENSE BLOCK *****
  */
@@ -44,10 +45,15 @@
 #include "DNA_screen_types.h"
 #include "DNA_space_types.h"
 #include "DNA_world_types.h"
+#include "DNA_object_types.h"
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
 
 #include "BLI_blenlib.h"
 #include "BLI_threads.h"
 #include "BLI_utildefines.h"
+#include "BLI_math.h"
+#include "BLI_math_geom.h"
 
 #include "BKE_blender.h"
 #include "BKE_context.h"
@@ -56,6 +62,10 @@
 #include "BKE_main.h"
 #include "BKE_multires.h"
 #include "BKE_report.h"
+#include "BKE_cdderivedmesh.h"
+#include "BKE_modifier.h"
+#include "BKE_DerivedMesh.h"
+#include "BKE_subsurf.h"
 
 #include "RE_pipeline.h"
 #include "RE_shader_ext.h"
@@ -74,6 +84,1133 @@
 
 #include "object_intern.h"
 
+/* ****************** multires BAKING ********************** */
+
+/* holder of per-object data needed for bake job
+   needed to make job totally thread-safe */
+typedef struct MultiresBakerJobData {
+	struct MultiresBakerJobData *next, *prev;
+	DerivedMesh *lores_dm, *hires_dm;
+	int simple, lvl, tot_lvl;
+} MultiresBakerJobData;
+
+/* data passing to multires-baker job */
+typedef struct {
+	ListBase data;
+	int bake_clear, bake_filter;
+	short mode, use_lores_mesh;
+} MultiresBakeJob;
+
+/* data passing to multires baker */
+typedef struct {
+	DerivedMesh *lores_dm, *hires_dm;
+	int simple, lvl, tot_lvl, bake_filter;
+	short mode, use_lores_mesh;
+
+	int tot_obj, tot_image;
+	ListBase image;
+
+	int baked_objects, baked_faces;
+
+	short *stop;
+	short *do_update;
+	float *progress;
+} MultiresBakeRender;
+
+typedef void (*MPassKnownData)(DerivedMesh *lores_dm, DerivedMesh *hires_dm, const void *bake_data,
+                               const int face_index, const int lvl, const float st[2],
+                               float tangmat[3][3], const int x, const int y);
+
+typedef void* (*MInitBakeData)(MultiresBakeRender *bkr, Image* ima);
+typedef void (*MApplyBakeData)(void *bake_data);
+typedef void (*MFreeBakeData)(void *bake_data);
+
+typedef struct {
+	MVert *mvert;
+	MFace *mface;
+	MTFace *mtface;
+	float *pvtangent;
+	float *precomputed_normals;
+	int w, h;
+	int face_index;
+	int i0, i1, i2;
+	DerivedMesh *lores_dm, *hires_dm;
+	int lvl;
+	void *bake_data;
+	MPassKnownData pass_data;
+} MResolvePixelData;
+
+typedef void (*MFlushPixel)(const MResolvePixelData *data, const int x, const int y);
+
+typedef struct {
+	int w, h;
+	char *texels;
+	const MResolvePixelData *data;
+	MFlushPixel flush_pixel;
+} MBakeRast;
+
+typedef struct {
+	float *heights;
+	float height_min, height_max;
+	Image *ima;
+	DerivedMesh *ssdm;
+} MHeightBakeData;
+
+static void multiresbake_get_normal(const MResolvePixelData *data, float norm[], const int face_num, const int vert_index)
+{
+	unsigned int indices[]= {data->mface[face_num].v1, data->mface[face_num].v2,
+                             data->mface[face_num].v3, data->mface[face_num].v4};
+	const int smoothnormal= (data->mface[face_num].flag & ME_SMOOTH);
+
+	if(!smoothnormal)  { /* flat */
+		if(data->precomputed_normals) {
+			copy_v3_v3(norm, &data->precomputed_normals[3*face_num]);
+		} else {
+			float nor[3];
+			float *p0, *p1, *p2;
+			const int iGetNrVerts= data->mface[face_num].v4!=0 ? 4 : 3;
+
+			p0= data->mvert[indices[0]].co;
+			p1= data->mvert[indices[1]].co;
+			p2= data->mvert[indices[2]].co;
+
+			if(iGetNrVerts==4) {
+				float *p3= data->mvert[indices[3]].co;
+				normal_quad_v3(nor, p0, p1, p2, p3);
+			} else {
+				normal_tri_v3(nor, p0, p1, p2);
+			}
+
+			copy_v3_v3(norm, nor);
+		}
+	} else {
+		short *no= data->mvert[indices[vert_index]].no;
+
+		normal_short_to_float_v3(norm, no);
+		normalize_v3(norm);
+	}
+}
+
+static void init_bake_rast(MBakeRast *bake_rast, const ImBuf *ibuf, const MResolvePixelData *data, MFlushPixel flush_pixel)
+{
+	memset(bake_rast, 0, sizeof(MBakeRast));
+
+	bake_rast->texels = ibuf->userdata;
+	bake_rast->w= ibuf->x;
+	bake_rast->h= ibuf->y;
+	bake_rast->data= data;
+	bake_rast->flush_pixel= flush_pixel;
+}
+
+static void flush_pixel(const MResolvePixelData *data, const int x, const int y)
+{
+	float st[2]= {(x+0.5f)/data->w, (y+0.5f)/data->h};
+	float *st0, *st1, *st2;
+	float *tang0, *tang1, *tang2;
+	float no0[3], no1[3], no2[3];
+	float fUV[2], from_tang[3][3], to_tang[3][3];
+	float u, v, w, sign;
+	int r;
+
+	const int i0= data->i0;
+	const int i1= data->i1;
+	const int i2= data->i2;
+
+	st0= data->mtface[data->face_index].uv[i0];
+	st1= data->mtface[data->face_index].uv[i1];
+	st2= data->mtface[data->face_index].uv[i2];
+
+	tang0= data->pvtangent + data->face_index*16 + i0*4;
+	tang1= data->pvtangent + data->face_index*16 + i1*4;
+	tang2= data->pvtangent + data->face_index*16 + i2*4;
+
+	multiresbake_get_normal(data, no0, data->face_index, i0);	/* can optimize these 3 into one call */
+	multiresbake_get_normal(data, no1, data->face_index, i1);
+	multiresbake_get_normal(data, no2, data->face_index, i2);
+
+	resolve_tri_uv(fUV, st, st0, st1, st2);
+
+	u= fUV[0];
+	v= fUV[1];
+	w= 1-u-v;
+
+	/* the sign is the same at all face vertices for any non degenerate face.
+	   Just in case we clamp the interpolated value though. */
+	sign= (tang0[3]*u + tang1[3]*v + tang2[3]*w)<0 ? (-1.0f) : 1.0f;
+
+	/* this sequence of math is designed specifically as is with great care
+	   to be compatible with our shader. Please don't change without good reason. */
+	for(r= 0; r<3; r++) {
+		from_tang[0][r]= tang0[r]*u + tang1[r]*v + tang2[r]*w;
+		from_tang[2][r]= no0[r]*u + no1[r]*v + no2[r]*w;
+	}
+
+	cross_v3_v3v3(from_tang[1], from_tang[2], from_tang[0]);  /* B = sign * cross(N, T)  */
+	mul_v3_fl(from_tang[1], sign);
+	invert_m3_m3(to_tang, from_tang);
+	/* sequence end */
+
+	data->pass_data(data->lores_dm, data->hires_dm, data->bake_data,
+	                data->face_index, data->lvl, st, to_tang, x, y);
+}
+
+static void set_rast_triangle(const MBakeRast *bake_rast, const int x, const int y)
+{
+	const int w= bake_rast->w;
+	const int h= bake_rast->h;
+
+	if(x>=0 && x<w && y>=0 && y<h) {
+		if((bake_rast->texels[y*w+x])==0) {
+			flush_pixel(bake_rast->data, x, y);
+			bake_rast->texels[y*w+x]= FILTER_MASK_USED;
+		}
+	}
+}
+
+static void rasterize_half(const MBakeRast *bake_rast,
+                           const float s0_s, const float t0_s, const float s1_s, const float t1_s,
+                           const float s0_l, const float t0_l, const float s1_l, const float t1_l,
+                           const int y0_in, const int y1_in, const int is_mid_right)
+{
+	const int s_stable= fabsf(t1_s-t0_s)>FLT_EPSILON ? 1 : 0;
+	const int l_stable= fabsf(t1_l-t0_l)>FLT_EPSILON ? 1 : 0;
+	const int w= bake_rast->w;
+	const int h= bake_rast->h;
+	int y, y0, y1;
+
+	if(y1_in<=0 || y0_in>=h)
+		return;
+
+	y0= y0_in<0 ? 0 : y0_in;
+	y1= y1_in>=h ? h : y1_in;
+
+	for(y= y0; y<y1; y++) {
+		/*-b(x-x0) + a(y-y0) = 0 */
+		int iXl, iXr, x;
+		float x_l= s_stable!=0 ? (s0_s + (((s1_s-s0_s)*(y-t0_s))/(t1_s-t0_s))) : s0_s;
+		float x_r= l_stable!=0 ? (s0_l + (((s1_l-s0_l)*(y-t0_l))/(t1_l-t0_l))) : s0_l;
+
+		if(is_mid_right!=0)
+			SWAP(float, x_l, x_r);
+
+		iXl= (int)ceilf(x_l);
+		iXr= (int)ceilf(x_r);
+
+		if(iXr>0 && iXl<w) {
+			iXl= iXl<0?0:iXl;
+			iXr= iXr>=w?w:iXr;
+
+			for(x= iXl; x<iXr; x++)
+				set_rast_triangle(bake_rast, x, y);
+		}
+	}
+}
+
+static void bake_rasterize(const MBakeRast *bake_rast, const float st0_in[2], const float st1_in[2], const float st2_in[2])
+{
+	const int w= bake_rast->w;
+	const int h= bake_rast->h;
+	float slo= st0_in[0]*w - 0.5f;
+	float tlo= st0_in[1]*h - 0.5f;
+	float smi= st1_in[0]*w - 0.5f;
+	float tmi= st1_in[1]*h - 0.5f;
+	float shi= st2_in[0]*w - 0.5f;
+	float thi= st2_in[1]*h - 0.5f;
+	int is_mid_right= 0, ylo, yhi, yhi_beg;
+
+	/* skip degenerates */
+	if((slo==smi && tlo==tmi) || (slo==shi && tlo==thi) || (smi==shi && tmi==thi))
+		return;
+
+	/* sort by T */
+	if(tlo>tmi && tlo>thi) {
+		SWAP(float, shi, slo);
+		SWAP(float, thi, tlo);
+	} else if(tmi>thi) {
+		SWAP(float, shi, smi);
+		SWAP(float, thi, tmi);
+	}
+
+	if(tlo>tmi) {
+		SWAP(float, slo, smi);
+		SWAP(float, tlo, tmi);
+	}
+
+	/* check if mid point is to the left or to the right of the lo-hi edge */
+	is_mid_right= (-(shi-slo)*(tmi-thi) + (thi-tlo)*(smi-shi))>0 ? 1 : 0;
+	ylo= (int) ceilf(tlo);
+	yhi_beg= (int) ceilf(tmi);
+	yhi= (int) ceilf(thi);
+
+	/*if(fTmi>ceilf(fTlo))*/
+	rasterize_half(bake_rast, slo, tlo, smi, tmi, slo, tlo, shi, thi, ylo, yhi_beg, is_mid_right);
+	rasterize_half(bake_rast, smi, tmi, shi, thi, slo, tlo, shi, thi, yhi_beg, yhi, is_mid_right);
+}
+
+static int multiresbake_test_break(MultiresBakeRender *bkr)
+{
+	if(!bkr->stop) {
+		/* this means baker is executed outside from job system */
+		return 0;
+	}
+
+	return G.afbreek;
+}
+
+static void do_multires_bake(MultiresBakeRender *bkr, Image* ima, MPassKnownData passKnownData,
+                             MInitBakeData initBakeData, MApplyBakeData applyBakeData, MFreeBakeData freeBakeData)
+{
+	DerivedMesh *dm= bkr->lores_dm;
+	ImBuf *ibuf= BKE_image_get_ibuf(ima, NULL);
+	const int lvl= bkr->lvl;
+	const int tot_face= dm->getNumFaces(dm);
+	MVert *mvert= dm->getVertArray(dm);
+	MFace *mface= dm->getFaceArray(dm);
+	MTFace *mtface= dm->getFaceDataArray(dm, CD_MTFACE);
+	float *pvtangent= NULL;
+
+	if(CustomData_get_layer_index(&dm->faceData, CD_TANGENT) == -1)
+		DM_add_tangent_layer(dm);
+
+	pvtangent= DM_get_face_data_layer(dm, CD_TANGENT);
+
+	if(tot_face > 0) {  /* sanity check */
+		int f= 0;
+		MBakeRast bake_rast;
+		MResolvePixelData data={NULL};
+
+		data.mface= mface;
+		data.mvert= mvert;
+		data.mtface= mtface;
+		data.pvtangent= pvtangent;
+		data.precomputed_normals= dm->getFaceDataArray(dm, CD_NORMAL);	/* don't strictly need this */
+		data.w= ibuf->x;
+		data.h= ibuf->y;
+		data.lores_dm= dm;
+		data.hires_dm= bkr->hires_dm;
+		data.lvl= lvl;
+		data.pass_data= passKnownData;
+
+		if(initBakeData)
+			data.bake_data= initBakeData(bkr, ima);
+
+		init_bake_rast(&bake_rast, ibuf, &data, flush_pixel);
+
+		for(f= 0; f<tot_face; f++) {
+			MTFace *mtfate= &mtface[f];
+			int verts[3][2], nr_tris, t;
+
+			if(multiresbake_test_break(bkr))
+				break;
+
+			if(mtfate->tpage!=ima)
+				continue;
+
+			data.face_index= f;
+
+			/* might support other forms of diagonal splits later on such as
+			   split by shortest diagonal.*/
+			verts[0][0]=0;
+			verts[1][0]=1;
+			verts[2][0]=2;
+
+			verts[0][1]=0;
+			verts[1][1]=2;
+			verts[2][1]=3;
+
+			nr_tris= mface[f].v4!=0 ? 2 : 1;
+			for(t= 0; t<nr_tris; t++) {
+				data.i0= verts[0][t];
+				data.i1= verts[1][t];
+				data.i2 =verts[2][t];
+
+				bake_rasterize(&bake_rast, mtfate->uv[data.i0], mtfate->uv[data.i1], mtfate->uv[data.i2]);
+			}
+
+			bkr->baked_faces++;
+
+			if(bkr->do_update)
+				*bkr->do_update= 1;
+
+			if(bkr->progress)
+				*bkr->progress= ((float)bkr->baked_objects + (float)bkr->baked_faces / tot_face) / bkr->tot_obj;
+		}
+
+		if(applyBakeData)
+			applyBakeData(data.bake_data);
+
+		if(freeBakeData)
+			freeBakeData(data.bake_data);
+	}
+}
+
+static void interp_bilinear_quad_data(float data[4][3], float u, float v, float res[3])
+{
+	float vec[3];
+
+	copy_v3_v3(res, data[0]);
+	mul_v3_fl(res, (1-u)*(1-v));
+	copy_v3_v3(vec, data[1]);
+	mul_v3_fl(vec, u*(1-v)); add_v3_v3(res, vec);
+	copy_v3_v3(vec, data[2]);
+	mul_v3_fl(vec, u*v); add_v3_v3(res, vec);
+	copy_v3_v3(vec, data[3]);
+	mul_v3_fl(vec, (1-u)*v); add_v3_v3(res, vec);
+}
+
+static void interp_barycentric_tri_data(float data[3][3], float u, float v, float res[3])
+{
+	float vec[3];
+
+	copy_v3_v3(res, data[0]);
+	mul_v3_fl(res, u);
+	copy_v3_v3(vec, data[1]);
+	mul_v3_fl(vec, v); add_v3_v3(res, vec);
+	copy_v3_v3(vec, data[2]);
+	mul_v3_fl(vec, 1.0f-u-v); add_v3_v3(res, vec);
+}
+
+/* mode = 0: interpolate normals,
+   mode = 1: interpolate coord */
+static void interp_bilinear_grid(DMGridData *grid, int grid_size, float crn_x, float crn_y, int mode, float res[3])
+{
+	int x0, x1, y0, y1;
+	float u, v;
+	float data[4][3];
+
+	x0= (int) crn_x;
+	x1= x0>=(grid_size-1) ? (grid_size-1) : (x0+1);
+
+	y0= (int) crn_y;
+	y1= y0>=(grid_size-1) ? (grid_size-1) : (y0+1);
+
+	u= crn_x-x0;
+	v= crn_y-y0;
+
+	if(mode == 0) {
+		copy_v3_v3(data[0], grid[y0 * grid_size + x0].no);
+		copy_v3_v3(data[1], grid[y0 * grid_size + x1].no);
+		copy_v3_v3(data[2], grid[y1 * grid_size + x1].no);
+		copy_v3_v3(data[3], grid[y1 * grid_size + x0].no);
+	} else {
+		copy_v3_v3(data[0], grid[y0 * grid_size + x0].co);
+		copy_v3_v3(data[1], grid[y0 * grid_size + x1].co);
+		copy_v3_v3(data[2], grid[y1 * grid_size + x1].co);
+		copy_v3_v3(data[3], grid[y1 * grid_size + x0].co);
+	}
+
+	interp_bilinear_quad_data(data, u, v, res);
+}
+
+static void get_ccgdm_data(DerivedMesh *lodm, DerivedMesh *hidm,  const int lvl, const int face_index, const float u, const float v, float co[3], float n[3])
+{
+	MFace mface;
+	DMGridData **grid_data;
+	float crn_x, crn_y;
+	int grid_size, num_grids, S, face_side;
+	int *grid_offset, g_index;
+
+	lodm->getFace(lodm, face_index, &mface);
+
+	num_grids= hidm->getNumGrids(hidm);
+	grid_size= hidm->getGridSize(hidm);
+	grid_data= hidm->getGridData(hidm);
+	grid_offset= hidm->getGridOffset(hidm);
+
+	face_side= (grid_size<<1)-1;
+
+	if(lvl==0) {
+		g_index= grid_offset[face_index];
+		S= mdisp_rot_face_to_crn(mface.v4 ? 4 : 3, face_side, u*(face_side-1), v*(face_side-1), &crn_x, &crn_y);
+	} else {
+		const int *index= lodm->getFaceDataArray(lodm, CD_ORIGINDEX);
+		int side= (1 << (lvl-1)) + 1;
+		int grid_index= index[face_index];
+		int loc_offs= face_index % (1<<(2*lvl));
+		int cell_index= loc_offs % ((side-1)*(side-1));
+		int cell_side= grid_size / (side-1);
+		int row= cell_index / (side-1);
+		int col= cell_index % (side-1);
+
+		S= face_index / (1<<(2*(lvl-1))) - grid_offset[grid_index];
+		g_index= grid_offset[grid_index];
+
+		crn_y= (row * cell_side) + u * cell_side;
+		crn_x= (col * cell_side) + v * cell_side;
+	}
+
+	CLAMP(crn_x, 0.0f, grid_size);
+	CLAMP(crn_y, 0.0f, grid_size);
+
+	if(n != NULL)
+		interp_bilinear_grid(grid_data[g_index + S], grid_size, crn_x, crn_y, 0, n);
+
+	if(co != NULL)
+		interp_bilinear_grid(grid_data[g_index + S], grid_size, crn_x, crn_y, 1, co);
+}
+
+/* mode = 0: interpolate normals,
+   mode = 1: interpolate coord */
+static void interp_bilinear_mface(DerivedMesh *dm, MFace *mface, const float u, const float v, const int mode, float res[3])
+{
+	float data[4][3];
+
+	if(mode == 0) {
+		dm->getVertNo(dm, mface->v1, data[0]);
+		dm->getVertNo(dm, mface->v2, data[1]);
+		dm->getVertNo(dm, mface->v3, data[2]);
+		dm->getVertNo(dm, mface->v4, data[3]);
+	} else {
+		dm->getVertCo(dm, mface->v1, data[0]);
+		dm->getVertCo(dm, mface->v2, data[1]);
+		dm->getVertCo(dm, mface->v3, data[2]);
+		dm->getVertCo(dm, mface->v4, data[3]);
+	}
+
+	interp_bilinear_quad_data(data, u, v, res);
+}
+
+/* mode = 0: interpolate normals,
+   mode = 1: interpolate coord */
+static void interp_barycentric_mface(DerivedMesh *dm, MFace *mface, const float u, const float v, const int mode, float res[3])
+{
+	float data[3][3];
+
+	if(mode == 0) {
+		dm->getVertNo(dm, mface->v1, data[0]);
+		dm->getVertNo(dm, mface->v2, data[1]);
+		dm->getVertNo(dm, mface->v3, data[2]);
+	} else {
+		dm->getVertCo(dm, mface->v1, data[0]);
+		dm->getVertCo(dm, mface->v2, data[1]);
+		dm->getVertCo(dm, mface->v3, data[2]);
+	}
+
+	interp_barycentric_tri_data(data, u, v, res);
+}
+
+static void *init_heights_data(MultiresBakeRender *bkr, Image* ima)
+{
+	MHeightBakeData *height_data;
+	ImBuf *ibuf= BKE_image_get_ibuf(ima, NULL);
+
+	height_data= MEM_callocN(sizeof(MHeightBakeData), "MultiresBake heightData");
+
+	height_data->ima= ima;
+	height_data->heights= MEM_callocN(sizeof(float)*ibuf->x*ibuf->y, "MultiresBake heights");
+	height_data->height_max= -FLT_MAX;
+	height_data->height_min= FLT_MAX;
+
+	if(!bkr->use_lores_mesh) {
+		SubsurfModifierData smd= {{NULL}};
+		int ss_lvl= bkr->tot_lvl - bkr->lvl;
+
+		CLAMP(ss_lvl, 0, 6);
+
+		smd.levels= smd.renderLevels= ss_lvl;
+		smd.flags|= eSubsurfModifierFlag_SubsurfUv;
+
+		if(bkr->simple)
+			smd.subdivType= ME_SIMPLE_SUBSURF;
+
+		height_data->ssdm= subsurf_make_derived_from_derived(bkr->lores_dm, &smd, 0, NULL, 0, 0, 0);
+	}
+
+	return (void*)height_data;
+}
+
+static void apply_heights_data(void *bake_data)
+{
+	MHeightBakeData *height_data= (MHeightBakeData*)bake_data;
+	ImBuf *ibuf= BKE_image_get_ibuf(height_data->ima, NULL);
+	int x, y, i;
+	float height, *heights= height_data->heights;
+	float min= height_data->height_min, max= height_data->height_max;
+
+	for(x= 0; x<ibuf->x; x++) {
+		for(y =0; y<ibuf->y; y++) {
+			i= ibuf->x*y + x;
+
+			if(((char*)ibuf->userdata)[i] != FILTER_MASK_USED)
+				continue;
+
+			if(ibuf->rect_float) {
+				float *rrgbf= ibuf->rect_float + i*4;
+
+				if(max-min > 1e-5) height= (heights[i]-min)/(max-min);
+				else height= 0;
+
+				rrgbf[0]=rrgbf[1]=rrgbf[2]= height;
+			} else {
+				char *rrgb= (char*)ibuf->rect + i*4;
+
+				if(max-min > 1e-5) height= (heights[i]-min)/(max-min);
+				else height= 0;
+
+				rrgb[0]=rrgb[1]=rrgb[2]= FTOCHAR(height);
+			}
+		}
+	}
+}
+
+static void free_heights_data(void *bake_data)
+{
+	MHeightBakeData *height_data= (MHeightBakeData*)bake_data;
+
+	if(height_data->ssdm)
+		height_data->ssdm->release(height_data->ssdm);
+
+	MEM_freeN(height_data->heights);
+	MEM_freeN(height_data);
+}
+
+/* MultiresBake callback for heights baking
+   general idea:
+     - find coord of point with specified UV in hi-res mesh (let's call it p1)
+     - find coord of point and normal with specified UV in lo-res mesh (or subdivided lo-res
+       mesh to make texture smoother) let's call this point p0 and n.
+     - height wound be dot(n, p1-p0) */
+static void apply_heights_callback(DerivedMesh *lores_dm, DerivedMesh *hires_dm, const void *bake_data,
+                                   const int face_index, const int lvl, const float st[2],
+                                   float UNUSED(tangmat[3][3]), const int x, const int y)
+{
+	MTFace *mtface= CustomData_get_layer(&lores_dm->faceData, CD_MTFACE);
+	MFace mface;
+	Image *ima= mtface[face_index].tpage;
+	ImBuf *ibuf= BKE_image_get_ibuf(ima, NULL);
+	MHeightBakeData *height_data= (MHeightBakeData*)bake_data;
+	float uv[2], *st0, *st1, *st2, *st3;
+	int pixel= ibuf->x*y + x;
+	float vec[3], p0[3], p1[3], n[3], len;
+
+	lores_dm->getFace(lores_dm, face_index, &mface);
+
+	if(x==0 && y==0) {
+		zero_v3(p0);
+	}
+
+	st0= mtface[face_index].uv[0];
+	st1= mtface[face_index].uv[1];
+	st2= mtface[face_index].uv[2];
+
+	if(mface.v4) {
+		st3= mtface[face_index].uv[3];
+		resolve_quad_uv(uv, st, st0, st1, st2, st3);
+	} else
+		resolve_tri_uv(uv, st, st0, st1, st2);
+
+	CLAMP(uv[0], 0.0f, 1.0f);
+	CLAMP(uv[1], 0.0f, 1.0f);
+
+	get_ccgdm_data(lores_dm, hires_dm, lvl, face_index, uv[0], uv[1], p1, 0);
+
+	if(height_data->ssdm) {
+		//get_ccgdm_data_ss(lores_dm, height_data->ssdm, lvl, face_index, uv[0], uv[1], p0, n);
+		get_ccgdm_data(lores_dm, height_data->ssdm, 0, face_index, uv[0], uv[1], p0, n);
+	} else {
+		MFace mface;
+		lores_dm->getFace(lores_dm, face_index, &mface);
+
+		if(mface.v4) {
+			interp_bilinear_mface(lores_dm, &mface, uv[0], uv[1], 1, p0);
+			interp_bilinear_mface(lores_dm, &mface, uv[0], uv[1], 0, n);
+		} else {
+			interp_barycentric_mface(lores_dm, &mface, uv[0], uv[1], 1, p0);
+			interp_barycentric_mface(lores_dm, &mface, uv[0], uv[1], 0, n);
+		}
+	}
+
+	sub_v3_v3v3(vec, p1, p0);
+	//len= len_v3(vec);
+	len= dot_v3v3(n, vec);
+
+	height_data->heights[pixel]= len;
+	if(len<height_data->height_min) height_data->height_min= len;
+	if(len>height_data->height_max) height_data->height_max= len;
+
+	if(ibuf->rect_float) {
+		float *rrgbf= ibuf->rect_float + pixel*4;
+		rrgbf[3]= 1.0f;
+	} else {
+		char *rrgb= (char*)ibuf->rect + pixel*4;
+		rrgb[3]= 255;
+	}
+}
+
+/* MultiresBake callback for normals' baking
+   general idea:
+     - find coord and normal of point with specified UV in hi-res mesh
+     - multiply it by tangmat
+     - vector in color space would be norm(vec) /2 + (0.5, 0.5, 0.5) */
+static void apply_tangmat_callback(DerivedMesh *lores_dm, DerivedMesh *hires_dm, const void *UNUSED(bake_data),
+                                   const int face_index, const int lvl, const float st[2],
+                                   float tangmat[3][3], const int x, const int y)
+{
+	MTFace *mtface= CustomData_get_layer(&lores_dm->faceData, CD_MTFACE);
+	MFace mface;
+	Image *ima= mtface[face_index].tpage;
+	ImBuf *ibuf= BKE_image_get_ibuf(ima, NULL);
+	float uv[2], *st0, *st1, *st2, *st3;
+	int pixel= ibuf->x*y + x;
+	float n[3], vec[3], tmp[3]= {0.5, 0.5, 0.5};
+
+	lores_dm->getFace(lores_dm, face_index, &mface);
+
+	st0= mtface[face_index].uv[0];
+	st1= mtface[face_index].uv[1];
+	st2= mtface[face_index].uv[2];
+
+	if(mface.v4) {
+		st3= mtface[face_index].uv[3];
+		resolve_quad_uv(uv, st, st0, st1, st2, st3);
+	} else
+		resolve_tri_uv(uv, st, st0, st1, st2);
+
+	CLAMP(uv[0], 0.0f, 1.0f);
+	CLAMP(uv[1], 0.0f, 1.0f);
+
+	get_ccgdm_data(lores_dm, hires_dm, lvl, face_index, uv[0], uv[1], NULL, n);
+
+	mul_v3_m3v3(vec, tangmat, n);
+	normalize_v3(vec);
+	mul_v3_fl(vec, 0.5);
+	add_v3_v3(vec, tmp);
+
+	if(ibuf->rect_float) {
+		float *rrgbf= ibuf->rect_float + pixel*4;
+		rrgbf[0]= vec[0];
+		rrgbf[1]= vec[1];
+		rrgbf[2]= vec[2];
+		rrgbf[3]= 1.0f;
+	} else {
+		char *rrgb= (char*)ibuf->rect + pixel*4;
+		rrgb[0]= FTOCHAR(vec[0]);
+		rrgb[1]= FTOCHAR(vec[1]);
+		rrgb[2]= FTOCHAR(vec[2]);
+		rrgb[3]= 255;
+	}
+}
+
+static void count_images(MultiresBakeRender *bkr)
+{
+	int a, totface;
+	DerivedMesh *dm= bkr->lores_dm;
+	MTFace *mtface= CustomData_get_layer(&dm->faceData, CD_MTFACE);
+
+	bkr->image.first= bkr->image.last= NULL;
+	bkr->tot_image= 0;
+
+	totface= dm->getNumFaces(dm);
+
+	for(a= 0; a<totface; a++)
+		mtface[a].tpage->id.flag&= ~LIB_DOIT;
+
+	for(a= 0; a<totface; a++) {
+		Image *ima= mtface[a].tpage;
+		if((ima->id.flag&LIB_DOIT)==0) {
+			LinkData *data= BLI_genericNodeN(ima);
+			BLI_addtail(&bkr->image, data);
+			bkr->tot_image++;
+			ima->id.flag|= LIB_DOIT;
+		}
+	}
+
+	for(a= 0; a<totface; a++)
+		mtface[a].tpage->id.flag&= ~LIB_DOIT;
+}
+
+static void bake_images(MultiresBakeRender *bkr)
+{
+	LinkData *link;
+
+	for(link= bkr->image.first; link; link= link->next) {
+		Image *ima= (Image*)link->data;
+		ImBuf *ibuf= BKE_image_get_ibuf(ima, NULL);
+
+		if(ibuf->x>0 && ibuf->y>0) {
+			ibuf->userdata= MEM_callocN(ibuf->y*ibuf->x, "MultiresBake imbuf mask");
+
+			switch(bkr->mode) {
+				case RE_BAKE_NORMALS:
+					do_multires_bake(bkr, ima, apply_tangmat_callback, NULL, NULL, NULL);
+					break;
+				case RE_BAKE_DISPLACEMENT:
+					do_multires_bake(bkr, ima, apply_heights_callback, init_heights_data,
+					                 apply_heights_data, free_heights_data);
+					break;
+			}
+		}
+
+		ima->id.flag|= LIB_DOIT;
+	}
+}
+
+static void finish_images(MultiresBakeRender *bkr)
+{
+	LinkData *link;
+
+	for(link= bkr->image.first; link; link= link->next) {
+		Image *ima= (Image*)link->data;
+		int i;
+		ImBuf *ibuf= BKE_image_get_ibuf(ima, NULL);
+
+		if(ibuf->x<=0 || ibuf->y<=0)
+			continue;
+
+		/* Margin */
+		if(bkr->bake_filter) {
+			char *temprect;
+
+			/* extend the mask +2 pixels from the image,
+			 * this is so colors dont blend in from outside */
+
+			for(i=0; i<bkr->bake_filter; i++)
+				IMB_mask_filter_extend((char *)ibuf->userdata, ibuf->x, ibuf->y);
+
+			temprect = MEM_dupallocN(ibuf->userdata);
+
+			/* expand twice to clear this many pixels, so they blend back in */
+			IMB_mask_filter_extend(temprect, ibuf->x, ibuf->y);
+			IMB_mask_filter_extend(temprect, ibuf->x, ibuf->y);
+
+			/* clear all pixels in the margin */
+			IMB_mask_clear(ibuf, temprect, FILTER_MASK_MARGIN);
+			MEM_freeN(temprect);
+
+			for(i= 0; i<bkr->bake_filter; i++)
+				IMB_filter_extend(ibuf, (char *)ibuf->userdata);
+		}
+
+		ibuf->userflags|= IB_BITMAPDIRTY;
+		if(ibuf->mipmap[0]) {
+			ibuf->userflags|= IB_MIPMAP_INVALID;
+			imb_freemipmapImBuf(ibuf);
+		}
+
+		if(ibuf->userdata) {
+			MEM_freeN(ibuf->userdata);
+			ibuf->userdata= NULL;
+		}
+	}
+}
+
+static void multiresbake_start(MultiresBakeRender *bkr)
+{
+	count_images(bkr);
+	bake_images(bkr);
+	finish_images(bkr);
+}
+
+static int multiresbake_check(bContext *C, wmOperator *op) {
+	Scene *scene= CTX_data_scene(C);
+	Object *ob;
+	Mesh *me;
+	MultiresModifierData *mmd;
+	int ok= 1, a;
+
+	CTX_DATA_BEGIN(C, Base*, base, selected_editable_bases) {
+		ob= base->object;
+
+		if(ob->type != OB_MESH) {
+			BKE_report(op->reports, RPT_ERROR, "Basking of multires data only works with active object which is a mesh");
+
+			ok= 0;
+			break;
+		}
+
+		me= (Mesh*)ob->data;
+		mmd= get_multires_modifier(scene, ob, 0);
+
+		/* Multi-resolution should be and be last in the stack */
+		if(ok && mmd) {
+			ModifierData *md;
+
+			ok= mmd->totlvl>0;
+
+			for(md = (ModifierData*)mmd->modifier.next; md && ok; md = md->next) {
+				if (modifier_isEnabled(scene, md, eModifierMode_Realtime)) {
+					ok= 0;
+				}
+			}
+		} else ok= 0;
+
+		if(!ok) {
+			BKE_report(op->reports, RPT_ERROR, "Multires data baking requires multi-resolution object");
+
+			break;
+		}
+
+		if(!me->mtface) {
+			BKE_report(op->reports, RPT_ERROR, "Mesh should be unwrapped before multires data baking");
+
+			ok= 0;
+		} else {
+			a= me->totface;
+			while (ok && a--) {
+				Image *ima= me->mtface[a].tpage;
+
+				if(!ima) {
+					BKE_report(op->reports, RPT_ERROR, "You should have active texture to use multires baker");
+
+					ok= 0;
+				} else {
+					ImBuf *ibuf= BKE_image_get_ibuf(ima, NULL);
+
+					if(!ibuf) {
+						BKE_report(op->reports, RPT_ERROR, "Baking should happend to image with image buffer");
+
+						ok= 0;
+					} else {
+						if(ibuf->rect==NULL && ibuf->rect_float==NULL)
+							ok= 0;
+
+						if(ibuf->rect_float && !(ibuf->channels==0 || ibuf->channels==4))
+							ok= 0;
+
+						if(!ok)
+							BKE_report(op->reports, RPT_ERROR, "Baking to unsupported image type");
+					}
+				}
+			}
+		}
+
+		if(!ok)
+			break;
+	}
+	CTX_DATA_END;
+
+	return ok;
+}
+
+static DerivedMesh *multiresbake_create_loresdm(Scene *scene, Object *ob, int *lvl)
+{
+	DerivedMesh *dm;
+	MultiresModifierData *mmd= get_multires_modifier(scene, ob, 0);
+	Mesh *me= (Mesh*)ob->data;
+
+	*lvl= mmd->lvl;
+
+	if(mmd->lvl==0) {
+		DerivedMesh *tmp_dm= CDDM_from_mesh(me, ob);
+		dm= CDDM_copy(tmp_dm);
+		tmp_dm->release(tmp_dm);
+	} else {
+		MultiresModifierData tmp_mmd= *mmd;
+		DerivedMesh *cddm= CDDM_from_mesh(me, ob);
+
+		tmp_mmd.lvl= mmd->lvl;
+		dm= multires_dm_create_from_derived(&tmp_mmd, 1, cddm, ob, 0, 0);
+		cddm->release(cddm);
+	}
+
+	return dm;
+}
+
+static DerivedMesh *multiresbake_create_hiresdm(Scene *scene, Object *ob, int *lvl, int *simple)
+{
+	Mesh *me= (Mesh*)ob->data;
+	MultiresModifierData *mmd= get_multires_modifier(scene, ob, 0);
+	MultiresModifierData tmp_mmd= *mmd;
+	DerivedMesh *cddm= CDDM_from_mesh(me, ob);
+	DerivedMesh *dm;
+
+	*lvl= mmd->totlvl;
+	*simple= mmd->simple;
+
+	tmp_mmd.lvl= mmd->totlvl;
+	dm= multires_dm_create_from_derived(&tmp_mmd, 1, cddm, ob, 0, 0);
+	cddm->release(cddm);
+
+	return dm;
+}
+
+static void clear_images(MTFace *mtface, int totface)
+{
+	int a;
+	float vec[4]= {0.0f, 0.0f, 0.0f, 0.0f};
+
+	for(a= 0; a<totface; a++)
+		mtface[a].tpage->id.flag&= ~LIB_DOIT;
+
+	for(a= 0; a<totface; a++) {
+		Image *ima= mtface[a].tpage;
+
+		if((ima->id.flag&LIB_DOIT)==0) {
+			ImBuf *ibuf= BKE_image_get_ibuf(ima, NULL);
+
+			IMB_rectfill(ibuf, vec);
+			ima->id.flag|= LIB_DOIT;
+		}
+	}
+
+	for(a= 0; a<totface; a++)
+		mtface[a].tpage->id.flag&= ~LIB_DOIT;
+}
+
+static int multiresbake_image_exec_locked(bContext *C, wmOperator *op)
+{
+	Object *ob;
+	Scene *scene= CTX_data_scene(C);
+
+	if(!multiresbake_check(C, op))
+		return OPERATOR_CANCELLED;
+
+	if(scene->r.bake_flag&R_BAKE_CLEAR) {  /* clear images */
+		CTX_DATA_BEGIN(C, Base*, base, selected_editable_bases) {
+			Mesh *me;
+
+			ob= base->object;
+			me= (Mesh*)ob->data;
+
+			clear_images(me->mtface, me->totface);
+		}
+		CTX_DATA_END;
+	}
+
+	CTX_DATA_BEGIN(C, Base*, base, selected_editable_bases) {
+		MultiresBakeRender bkr= {0};
+
+		ob= base->object;
+
+		/* copy data stored in job descriptor */
+		bkr.bake_filter= scene->r.bake_filter;
+		bkr.mode= scene->r.bake_mode;
+		bkr.use_lores_mesh= scene->r.bake_flag&R_BAKE_LORES_MESH;
+
+		/* create low-resolution DM (to bake to) and hi-resolution DM (to bake from) */
+		bkr.lores_dm= multiresbake_create_loresdm(scene, ob, &bkr.lvl);
+		bkr.hires_dm= multiresbake_create_hiresdm(scene, ob, &bkr.tot_lvl, &bkr.simple);
+
+		multiresbake_start(&bkr);
+
+		BLI_freelistN(&bkr.image);
+
+		bkr.lores_dm->release(bkr.lores_dm);
+		bkr.hires_dm->release(bkr.hires_dm);
+	}
+	CTX_DATA_END;
+
+	return OPERATOR_FINISHED;
+}
+
+/* Multiresbake adopted for job-system executing */
+static void init_multiresbake_job(bContext *C, MultiresBakeJob *bkj)
+{
+	Scene *scene= CTX_data_scene(C);
+	Object *ob;
+
+	/* backup scene settings, so their changing in UI would take no effect on baker */
+	bkj->bake_filter= scene->r.bake_filter;
+	bkj->mode= scene->r.bake_mode;
+	bkj->use_lores_mesh= scene->r.bake_flag&R_BAKE_LORES_MESH;
+	bkj->bake_clear= scene->r.bake_flag&R_BAKE_CLEAR;
+
+	CTX_DATA_BEGIN(C, Base*, base, selected_editable_bases) {
+		MultiresBakerJobData *data;
+		ob= base->object;
+
+		data= MEM_callocN(sizeof(MultiresBakerJobData), "multiresBaker derivedMesh_data");
+		data->lores_dm = multiresbake_create_loresdm(scene, ob, &data->lvl);
+		data->hires_dm = multiresbake_create_hiresdm(scene, ob, &data->tot_lvl, &data->simple);
+		BLI_addtail(&bkj->data, data);
+	}
+	CTX_DATA_END;
+}
+
+static void multiresbake_startjob(void *bkv, short *stop, short *do_update, float *progress)
+{
+	MultiresBakerJobData *data;
+	MultiresBakeJob *bkj= bkv;
+	int baked_objects= 0, tot_obj;
+
+	tot_obj= BLI_countlist(&bkj->data);
+
+	if(bkj->bake_clear) {  /* clear images */
+		for(data= bkj->data.first; data; data= data->next) {
+			DerivedMesh *dm= data->lores_dm;
+			MTFace *mtface= CustomData_get_layer(&dm->faceData, CD_MTFACE);
+
+			clear_images(mtface, dm->getNumFaces(dm));
+		}
+	}
+
+	for(data= bkj->data.first; data; data= data->next) {
+		MultiresBakeRender bkr= {0};
+
+		/* copy data stored in job descriptor */
+		bkr.bake_filter= bkj->bake_filter;
+		bkr.mode= bkj->mode;
+		bkr.use_lores_mesh= bkj->use_lores_mesh;
+
+		/* create low-resolution DM (to bake to) and hi-resolution DM (to bake from) */
+		bkr.lores_dm= data->lores_dm;
+		bkr.hires_dm= data->hires_dm;
+		bkr.tot_lvl= data->tot_lvl;
+		bkr.lvl= data->lvl;
+		bkr.simple= data->simple;
+
+		/* needed for proper progress bar */
+		bkr.tot_obj= tot_obj;
+		bkr.baked_objects= baked_objects;
+
+		bkr.stop= stop;
+		bkr.do_update= do_update;
+		bkr.progress= progress;
+
+		multiresbake_start(&bkr);
+
+		BLI_freelistN(&bkr.image);
+
+		baked_objects++;
+	}
+}
+
+static void multiresbake_freejob(void *bkv)
+{
+	MultiresBakeJob *bkj= bkv;
+	MultiresBakerJobData *data, *next;
+
+	data= bkj->data.first;
+	while (data) {
+		next= data->next;
+		data->lores_dm->release(data->lores_dm);
+		data->hires_dm->release(data->hires_dm);
+		MEM_freeN(data);
+		data= next;
+	}
+
+	MEM_freeN(bkj);
+}
+
+static int multiresbake_image_exec(bContext *C, wmOperator *op)
+{
+	Scene *scene= CTX_data_scene(C);
+	MultiresBakeJob *bkr;
+	wmJob *steve;
+
+	if(!multiresbake_check(C, op))
+		return OPERATOR_CANCELLED;
+
+	bkr= MEM_callocN(sizeof(MultiresBakeJob), "MultiresBakeJob data");
+	init_multiresbake_job(C, bkr);
+
+	/* setup job */
+	steve= WM_jobs_get(CTX_wm_manager(C), CTX_wm_window(C), scene, "Multires Bake", WM_JOB_EXCL_RENDER|WM_JOB_PRIORITY|WM_JOB_PROGRESS);
+	WM_jobs_customdata(steve, bkr, multiresbake_freejob);
+	WM_jobs_timer(steve, 0.2, NC_IMAGE, 0); /* TODO - only draw bake image, can we enforce this */
+	WM_jobs_callbacks(steve, multiresbake_startjob, NULL, NULL, NULL);
+
+	G.afbreek= 0;
+
+	WM_jobs_start(CTX_wm_manager(C), steve);
+	WM_cursor_wait(0);
+
+	/* add modal handler for ESC */
+	WM_event_add_modal_handler(C, op);
+
+	return OPERATOR_RUNNING_MODAL;
+}
+
 /* ****************** render BAKING ********************** */
 
 /* threaded break test */
@@ -147,9 +1284,6 @@ static void init_bake_internal(BakeRender *bkr, bContext *C)
 {
 	Scene *scene= CTX_data_scene(C);
 
-	/* flush multires changes (for sculpt) */
-	multires_force_render_update(CTX_data_active_object(C));
-
 	/* get editmode results */
 	ED_object_exit_editmode(C, 0);  /* 0 = does not exit editmode */
 
@@ -273,43 +1407,59 @@ static int objects_bake_render_modal(bContext *C, wmOperator *UNUSED(op), wmEven
 	return OPERATOR_PASS_THROUGH;
 }
 
+static int is_multires_bake(Scene *scene)
+{
+	if ( ELEM(scene->r.bake_mode, RE_BAKE_NORMALS, RE_BAKE_DISPLACEMENT))
+		return scene->r.bake_flag & R_BAKE_MULTIRES;
+
+	return 0;
+}
+
 static int objects_bake_render_invoke(bContext *C, wmOperator *op, wmEvent *UNUSED(_event))
 {
 	Scene *scene= CTX_data_scene(C);
+	int result= OPERATOR_CANCELLED;
 
-	/* only one render job at a time */
-	if(WM_jobs_test(CTX_wm_manager(C), scene))
-		return OPERATOR_CANCELLED;
-	
-	if(test_bake_internal(C, op->reports)==0) {
-		return OPERATOR_CANCELLED;
-	}
-	else {
-		BakeRender *bkr= MEM_callocN(sizeof(BakeRender), "render bake");
-		wmJob *steve;
+	if(is_multires_bake(scene)) {
+		result= multiresbake_image_exec(C, op);
+	} else {
+		/* only one render job at a time */
+		if(WM_jobs_test(CTX_wm_manager(C), scene))
+			return OPERATOR_CANCELLED;
+
+		if(test_bake_internal(C, op->reports)==0) {
+			return OPERATOR_CANCELLED;
+		}
+		else {
+			BakeRender *bkr= MEM_callocN(sizeof(BakeRender), "render bake");
+			wmJob *steve;
 
-		init_bake_internal(bkr, C);
-		bkr->reports= op->reports;
+			init_bake_internal(bkr, C);
+			bkr->reports= op->reports;
 
-		/* setup job */
-		steve= WM_jobs_get(CTX_wm_manager(C), CTX_wm_window(C), scene, "Texture Bake", WM_JOB_EXCL_RENDER|WM_JOB_PRIORITY|WM_JOB_PROGRESS);
-		WM_jobs_customdata(steve, bkr, bake_freejob);
-		WM_jobs_timer(steve, 0.2, NC_IMAGE, 0); /* TODO - only draw bake image, can we enforce this */
-		WM_jobs_callbacks(steve, bake_startjob, NULL, bake_update, NULL);
+			/* setup job */
+			steve= WM_jobs_get(CTX_wm_manager(C), CTX_wm_window(C), scene, "Texture Bake", WM_JOB_EXCL_RENDER|WM_JOB_PRIORITY|WM_JOB_PROGRESS);
+			WM_jobs_customdata(steve, bkr, bake_freejob);
+			WM_jobs_timer(steve, 0.2, NC_IMAGE, 0); /* TODO - only draw bake image, can we enforce this */
+			WM_jobs_callbacks(steve, bake_startjob, NULL, bake_update, NULL);
 
-		G.afbreek= 0;
-		G.rendering = 1;
+			G.afbreek= 0;
+			G.rendering = 1;
 
-		WM_jobs_start(CTX_wm_manager(C), steve);
+			WM_jobs_start(CTX_wm_manager(C), steve);
 
-		WM_cursor_wait(0);
-		WM_event_add_notifier(C, NC_SCENE|ND_RENDER_RESULT, scene);
+			WM_cursor_wait(0);
 
-		/* add modal handler for ESC */
-		WM_event_add_modal_handler(C, op);
+			/* add modal handler for ESC */
+			WM_event_add_modal_handler(C, op);
+		}
+
+		result= OPERATOR_RUNNING_MODAL;
 	}
 
-	return OPERATOR_RUNNING_MODAL;
+	WM_event_add_notifier(C, NC_SCENE|ND_RENDER_RESULT, scene);
+
+	return result;
 }
 
 
@@ -317,46 +1467,53 @@ static int bake_image_exec(bContext *C, wmOperator *op)
 {
 	Main *bmain= CTX_data_main(C);
 	Scene *scene= CTX_data_scene(C);
+	int result= OPERATOR_CANCELLED;
 
+	if(is_multires_bake(scene)) {
+		result= multiresbake_image_exec_locked(C, op);
+	} else  {
+		if(test_bake_internal(C, op->reports)==0) {
+			return OPERATOR_CANCELLED;
+		}
+		else {
+			ListBase threads;
+			BakeRender bkr= {NULL};
 
-	if(test_bake_internal(C, op->reports)==0) {
-		return OPERATOR_CANCELLED;
-	}
-	else {
-		ListBase threads;
-		BakeRender bkr= {NULL};
+			init_bake_internal(&bkr, C);
+			bkr.reports= op->reports;
 
-		init_bake_internal(&bkr, C);
-		bkr.reports= op->reports;
+			RE_test_break_cb(bkr.re, NULL, thread_break);
+			G.afbreek= 0;	/* blender_test_break uses this global */
 
-		RE_test_break_cb(bkr.re, NULL, thread_break);
-		G.afbreek= 0;	/* blender_test_break uses this global */
+			RE_Database_Baking(bkr.re, bmain, scene, scene->lay, scene->r.bake_mode, (scene->r.bake_flag & R_BAKE_TO_ACTIVE)? OBACT: NULL);
 
-		RE_Database_Baking(bkr.re, bmain, scene, scene->lay, scene->r.bake_mode, (scene->r.bake_flag & R_BAKE_TO_ACTIVE)? OBACT: NULL);
+			/* baking itself is threaded, cannot use test_break in threads  */
+			BLI_init_threads(&threads, do_bake_render, 1);
+			bkr.ready= 0;
+			BLI_insert_thread(&threads, &bkr);
 
-		/* baking itself is threaded, cannot use test_break in threads  */
-		BLI_init_threads(&threads, do_bake_render, 1);
-		bkr.ready= 0;
-		BLI_insert_thread(&threads, &bkr);
+			while(bkr.ready==0) {
+				PIL_sleep_ms(50);
+				if(bkr.ready)
+					break;
 
-		while(bkr.ready==0) {
-			PIL_sleep_ms(50);
-			if(bkr.ready)
-				break;
+				/* used to redraw in 2.4x but this is just for exec in 2.5 */
+				if (!G.background)
+					blender_test_break();
+			}
+			BLI_end_threads(&threads);
 
-			/* used to redraw in 2.4x but this is just for exec in 2.5 */
-			if (!G.background)
-				blender_test_break();
-		}
-		BLI_end_threads(&threads);
+			if(bkr.tot==0) BKE_report(op->reports, RPT_ERROR, "No valid images found to bake to");
 
-		if(bkr.tot==0) BKE_report(op->reports, RPT_ERROR, "No valid images found to bake to");
+			finish_bake_internal(&bkr);
 
-		finish_bake_internal(&bkr);
+			result= OPERATOR_FINISHED;
+		}
 	}
 
 	WM_event_add_notifier(C, NC_SCENE|ND_RENDER_RESULT, scene);
-	return OPERATOR_FINISHED;
+
+	return result;
 }
 
 void OBJECT_OT_bake_image(wmOperatorType *ot)