Support multiple tangents for BI render & viewport

Normal Map node support for GLSL mode and the internal render (multiple tangents support).

The Normal Map node is a useful node which is present in the Cycles render.
It makes it possible to use normal mapping without additional material node in a node tree.
This patch implements Normal Map node for GLSL mode and the internal render.

Previously only the active UV layer was used to calculate tangents.

8 files changed, 97 insertions, 52 deletions

diff --git a/source/blender/render/extern/include/RE_shader_ext.h b/source/blender/render/extern/include/RE_shader_ext.h
index 12b97aedbd3..8b6dfb88b73 100644
--- a/source/blender/render/extern/include/RE_shader_ext.h
+++ b/source/blender/render/extern/include/RE_shader_ext.h
@@ -139,6 +139,7 @@ typedef struct ShadeInput {
 	float refcol[4], displace[3];
 	float strandco, tang[3], nmapnorm[3], nmaptang[4], stress, winspeed[4];
 	float duplilo[3], dupliuv[3];
+	float tangents[8][4]; /* 8 = MAX_MTFACE */
 
 	ShadeInputUV uv[8];   /* 8 = MAX_MTFACE */
 	ShadeInputCol col[8]; /* 8 = MAX_MCOL */
diff --git a/source/blender/render/intern/include/render_types.h b/source/blender/render/intern/include/render_types.h
index cef3a073084..6de5da3795a 100644
--- a/source/blender/render/intern/include/render_types.h
+++ b/source/blender/render/intern/include/render_types.h
@@ -334,6 +334,8 @@ typedef struct ObjectRen {
 	char (*mcol)[MAX_CUSTOMDATA_LAYER_NAME];
 	int  actmtface, actmcol, bakemtface;
 
+	char tangent_mask; /* which tangent layer should be calculated */
+
 	float obmat[4][4];	/* only used in convertblender.c, for instancing */
 
 	/* used on makeraytree */
diff --git a/source/blender/render/intern/include/renderdatabase.h b/source/blender/render/intern/include/renderdatabase.h
index 167ebc58030..b576d69d806 100644
--- a/source/blender/render/intern/include/renderdatabase.h
+++ b/source/blender/render/intern/include/renderdatabase.h
@@ -76,7 +76,7 @@ typedef struct VlakTableNode {
 	int *origindex;
 	int totmtface, totmcol;
 	float *surfnor;
-	float *tangent;
+	float *tangent_arrays[MAX_MTFACE];
 	struct RadFace **radface;
 } VlakTableNode;
 
@@ -137,7 +137,7 @@ struct MTFace *RE_vlakren_get_tface(struct ObjectRen *obr, VlakRen *ren, int n,
 struct MCol *RE_vlakren_get_mcol(struct ObjectRen *obr, VlakRen *ren, int n, char **name, int verify);
 int *RE_vlakren_get_origindex(struct ObjectRen *obr, VlakRen *vlak, int verify);
 float *RE_vlakren_get_surfnor(struct ObjectRen *obr, VlakRen *ren, int verify);
-float *RE_vlakren_get_nmap_tangent(struct ObjectRen *obr, VlakRen *ren, int verify);
+float *RE_vlakren_get_nmap_tangent(ObjectRen *obr, VlakRen *vlak, int index, bool verify);
 RadFace **RE_vlakren_get_radface(struct ObjectRen *obr, VlakRen *ren, int verify);
 void RE_vlakren_get_normal(struct Render *re, struct ObjectInstanceRen *obi, struct VlakRen *vlr, float *nor);
 
diff --git a/source/blender/render/intern/source/bake_api.c b/source/blender/render/intern/source/bake_api.c
index eff021c9b14..1a0ef4e64d4 100644
--- a/source/blender/render/intern/source/bake_api.c
+++ b/source/blender/render/intern/source/bake_api.c
@@ -425,7 +425,7 @@ static TriTessFace *mesh_calc_tri_tessface(
 
 	if (tangent) {
 		DM_ensure_normals(dm);
-		DM_calc_loop_tangents(dm);
+		DM_calc_loop_tangents(dm, true, NULL, 0);
 
 		tspace = dm->getLoopDataArray(dm, CD_TANGENT);
 		BLI_assert(tspace);
diff --git a/source/blender/render/intern/source/convertblender.c b/source/blender/render/intern/source/convertblender.c
index ccf54cb6bcd..b6ee88de290 100644
--- a/source/blender/render/intern/source/convertblender.c
+++ b/source/blender/render/intern/source/convertblender.c
@@ -304,7 +304,7 @@ static void calc_tangent_vector(ObjectRen *obr, VlakRen *vlr, int do_tangent)
 
 typedef struct {
 	ObjectRen *obr;
-
+	int mtface_index;
 } SRenderMeshToTangent;
 
 /* interface */
@@ -337,7 +337,7 @@ static void GetTextureCoordinate(const SMikkTSpaceContext *pContext, float r_uv[
 	//assert(vert_index>=0 && vert_index<4);
 	SRenderMeshToTangent *pMesh = (SRenderMeshToTangent *) pContext->m_pUserData;
 	VlakRen *vlr= RE_findOrAddVlak(pMesh->obr, face_num);
-	MTFace *tface= RE_vlakren_get_tface(pMesh->obr, vlr, pMesh->obr->actmtface, NULL, 0);
+	MTFace *tface= RE_vlakren_get_tface(pMesh->obr, vlr, pMesh->mtface_index, NULL, 0);
 	const float *coord;
 	
 	if (tface  != NULL) {
@@ -371,7 +371,7 @@ static void SetTSpace(const SMikkTSpaceContext *pContext, const float fvTangent[
 	//assert(vert_index>=0 && vert_index<4);
 	SRenderMeshToTangent *pMesh = (SRenderMeshToTangent *) pContext->m_pUserData;
 	VlakRen *vlr = RE_findOrAddVlak(pMesh->obr, face_num);
-	float *ftang = RE_vlakren_get_nmap_tangent(pMesh->obr, vlr, 1);
+	float *ftang = RE_vlakren_get_nmap_tangent(pMesh->obr, vlr, pMesh->mtface_index, true);
 	if (ftang!=NULL) {
 		copy_v3_v3(&ftang[iVert*4+0], fvTangent);
 		ftang[iVert*4+3]=fSign;
@@ -457,7 +457,12 @@ static void calc_vertexnormals(Render *UNUSED(re), ObjectRen *obr, bool do_verte
 		sInterface.m_getNormal = GetNormal;
 		sInterface.m_setTSpaceBasic = SetTSpace;
 
-		genTangSpaceDefault(&sContext);
+		for (a = 0; a < MAX_MTFACE; a++) {
+			if (obr->tangent_mask & 1 << a) {
+				mesh2tangent.mtface_index = a;
+				genTangSpaceDefault(&sContext);
+			}
+		}
 	}
 }
 
@@ -3113,7 +3118,8 @@ static void init_render_mesh(Render *re, ObjectRen *obr, int timeoffset)
 	float xn, yn, zn,  imat[3][3], mat[4][4];  //nor[3],
 	float *orco = NULL;
 	short (*loop_nors)[4][3] = NULL;
-	bool need_orco = false, need_stress = false, need_nmap_tangent = false, need_tangent = false, need_origindex = false;
+	bool need_orco = false, need_stress = false, need_tangent = false, need_origindex = false;
+	bool need_nmap_tangent_concrete = false;
 	int a, a1, ok, vertofs;
 	int end, totvert = 0;
 	bool do_autosmooth = false, do_displace = false;
@@ -3148,9 +3154,11 @@ static void init_render_mesh(Render *re, ObjectRen *obr, int timeoffset)
 			if (ma->mode_l & MA_NORMAP_TANG) {
 				if (me->mtpoly==NULL) {
 					need_orco= 1;
-					need_tangent= 1;
 				}
-				need_nmap_tangent= 1;
+				need_tangent= 1;
+			}
+			if (ma->mode2_l & MA_TANGENT_CONCRETE) {
+				need_nmap_tangent_concrete = true;
 			}
 		}
 	}
@@ -3161,7 +3169,7 @@ static void init_render_mesh(Render *re, ObjectRen *obr, int timeoffset)
 			need_orco= 1;
 			need_tangent= 1;
 		}
-		need_nmap_tangent= 1;
+		need_nmap_tangent_concrete = true;
 	}
 
 	/* check autosmooth and displacement, we then have to skip only-verts optimize
@@ -3274,14 +3282,13 @@ static void init_render_mesh(Render *re, ObjectRen *obr, int timeoffset)
 			/* store customdata names, because DerivedMesh is freed */
 			RE_set_customdata_names(obr, &dm->faceData);
 
-			/* add tangent layer if we need one */
-			if (need_nmap_tangent!=0 && CustomData_get_layer_index(&dm->faceData, CD_TANGENT) == -1) {
-				bool generate_data = false;
-				if (CustomData_get_layer_index(&dm->loopData, CD_TANGENT) == -1) {
-					dm->calcLoopTangents(dm);
-					generate_data = true;
-				}
-				DM_generate_tangent_tessface_data(dm, generate_data);
+			/* add tangent layers if we need */
+			if ((ma->nmap_tangent_names_count && need_nmap_tangent_concrete) || need_tangent) {
+				dm->calcLoopTangents(
+				        dm, need_tangent,
+				        (const char (*)[MAX_NAME])ma->nmap_tangent_names, ma->nmap_tangent_names_count);
+				obr->tangent_mask = dm->tangent_mask;
+				DM_generate_tangent_tessface_data(dm, need_nmap_tangent_concrete || need_tangent);
 			}
 			
 			/* still to do for keys: the correct local texture coordinate */
@@ -3401,7 +3408,7 @@ static void init_render_mesh(Render *re, ObjectRen *obr, int timeoffset)
 								CustomDataLayer *layer;
 								MTFace *mtface, *mtf;
 								MCol *mcol, *mc;
-								int index, mtfn= 0, mcn= 0, mtng=0, mln = 0, vindex;
+								int index, mtfn= 0, mcn= 0, mln = 0, vindex;
 								char *name;
 								int nr_verts = v4!=0 ? 4 : 3;
 
@@ -3424,17 +3431,24 @@ static void init_render_mesh(Render *re, ObjectRen *obr, int timeoffset)
 										for (vindex=0; vindex<nr_verts; vindex++)
 											mc[vindex]=mcol[a*4+rev_tab[vindex]];
 									}
-									else if (layer->type == CD_TANGENT && mtng < 1) {
-										if (need_nmap_tangent != 0) {
-											const float * tangent = (const float *) layer->data;
-											float * ftang = RE_vlakren_get_nmap_tangent(obr, vlr, 1);
+									else if (layer->type == CD_TANGENT) {
+										if (need_nmap_tangent_concrete || need_tangent) {
+											int uv_start = CustomData_get_layer_index(&dm->faceData, CD_MTFACE);
+											int uv_index = CustomData_get_named_layer_index(&dm->faceData, CD_MTFACE, layer->name);
+											BLI_assert(uv_start >= 0 && uv_index >= 0);
+											if ((uv_start < 0 || uv_index < 0))
+												continue;
+											int n = uv_index - uv_start;
+
+											const float *tangent = (const float *) layer->data;
+											float *ftang = RE_vlakren_get_nmap_tangent(obr, vlr, n, true);
+
 											for (vindex=0; vindex<nr_verts; vindex++) {
 												copy_v4_v4(ftang+vindex*4, tangent+a*16+rev_tab[vindex]*4);
 												mul_mat3_m4_v3(mat, ftang+vindex*4);
 												normalize_v3(ftang+vindex*4);
 											}
 										}
-										mtng++;
 									}
 									else if (layer->type == CD_TESSLOOPNORMAL && mln < 1) {
 										if (loop_nors) {
@@ -3542,7 +3556,7 @@ static void init_render_mesh(Render *re, ObjectRen *obr, int timeoffset)
 		}
 
 		if (recalc_normals!=0 || need_tangent!=0)
-			calc_vertexnormals(re, obr, recalc_normals, need_tangent, need_nmap_tangent);
+			calc_vertexnormals(re, obr, recalc_normals, need_tangent, need_nmap_tangent_concrete);
 	}
 
 	MEM_SAFE_FREE(loop_nors);
diff --git a/source/blender/render/intern/source/multires_bake.c b/source/blender/render/intern/source/multires_bake.c
index 8eb6e7000ab..8c6d9c5f951 100644
--- a/source/blender/render/intern/source/multires_bake.c
+++ b/source/blender/render/intern/source/multires_bake.c
@@ -456,7 +456,7 @@ static void do_multires_bake(MultiresBakeRender *bkr, Image *ima, bool require_t
 
 		if (require_tangent) {
 			if (CustomData_get_layer_index(&dm->loopData, CD_TANGENT) == -1)
-				DM_calc_loop_tangents(dm);
+				DM_calc_loop_tangents(dm, true, NULL, 0);
 
 			pvtangent = DM_get_loop_data_layer(dm, CD_TANGENT);
 		}
diff --git a/source/blender/render/intern/source/renderdatabase.c b/source/blender/render/intern/source/renderdatabase.c
index e8db096c9a5..d3d26011a57 100644
--- a/source/blender/render/intern/source/renderdatabase.c
+++ b/source/blender/render/intern/source/renderdatabase.c
@@ -70,6 +70,7 @@
 #include "DNA_material_types.h" 
 #include "DNA_meshdata_types.h" 
 #include "DNA_texture_types.h"
+#include "DNA_listBase.h"
 #include "DNA_particle_types.h"
 
 #include "BKE_customdata.h"
@@ -380,19 +381,28 @@ float *RE_vlakren_get_surfnor(ObjectRen *obr, VlakRen *vlak, int verify)
 	return surfnor + (vlak->index & 255)*RE_SURFNOR_ELEMS;
 }
 
-float *RE_vlakren_get_nmap_tangent(ObjectRen *obr, VlakRen *vlak, int verify)
+float *RE_vlakren_get_nmap_tangent(ObjectRen *obr, VlakRen *vlak, int index, bool verify)
 {
-	float *tangent;
+	float **tangents;
 	int nr= vlak->index>>8;
 
-	tangent= obr->vlaknodes[nr].tangent;
-	if (tangent==NULL) {
-		if (verify) 
-			tangent= obr->vlaknodes[nr].tangent= MEM_callocN(256*RE_NMAP_TANGENT_ELEMS*sizeof(float), "tangent table");
+	tangents = obr->vlaknodes[nr].tangent_arrays;
+
+	if (index + 1 > 8) {
+		return NULL;
+	}
+
+	index = index < 0 ? 0: index;
+
+	if (tangents[index] == NULL) {
+		if (verify) {
+			tangents[index] = MEM_callocN(256*RE_NMAP_TANGENT_ELEMS*sizeof(float), "tangent table");
+		}
 		else
 			return NULL;
 	}
-	return tangent + (vlak->index & 255)*RE_NMAP_TANGENT_ELEMS;
+
+	return tangents[index] + (vlak->index & 255)*RE_NMAP_TANGENT_ELEMS;
 }
 
 RadFace **RE_vlakren_get_radface(ObjectRen *obr, VlakRen *vlak, int verify)
@@ -415,7 +425,8 @@ VlakRen *RE_vlakren_copy(ObjectRen *obr, VlakRen *vlr)
 	VlakRen *vlr1 = RE_findOrAddVlak(obr, obr->totvlak++);
 	MTFace *mtface, *mtface1;
 	MCol *mcol, *mcol1;
-	float *surfnor, *surfnor1, *tangent, *tangent1;
+	float *surfnor, *surfnor1;
+	float *tangent, *tangent1;
 	int *origindex, *origindex1;
 	RadFace **radface, **radface1;
 	int i, index = vlr1->index;
@@ -447,9 +458,11 @@ VlakRen *RE_vlakren_copy(ObjectRen *obr, VlakRen *vlr)
 		copy_v3_v3(surfnor1, surfnor);
 	}
 
-	tangent= RE_vlakren_get_nmap_tangent(obr, vlr, 0);
-	if (tangent) {
-		tangent1= RE_vlakren_get_nmap_tangent(obr, vlr1, 1);
+	for (i=0; i < MAX_MTFACE; i++) {
+		tangent = RE_vlakren_get_nmap_tangent(obr, vlr, i, false);
+		if (!tangent)
+			continue;
+		tangent1 = RE_vlakren_get_nmap_tangent(obr, vlr1, i, true);
 		memcpy(tangent1, tangent, sizeof(float)*RE_NMAP_TANGENT_ELEMS);
 	}
 
@@ -790,8 +803,10 @@ void free_renderdata_vlaknodes(VlakTableNode *vlaknodes)
 			MEM_freeN(vlaknodes[a].origindex);
 		if (vlaknodes[a].surfnor)
 			MEM_freeN(vlaknodes[a].surfnor);
-		if (vlaknodes[a].tangent)
-			MEM_freeN(vlaknodes[a].tangent);
+		for (int b = 0; b < MAX_MTFACE; b++) {
+			if (vlaknodes[a].tangent_arrays[b])
+				MEM_freeN(vlaknodes[a].tangent_arrays[b]);
+		}
 		if (vlaknodes[a].radface)
 			MEM_freeN(vlaknodes[a].radface);
 	}
diff --git a/source/blender/render/intern/source/shadeinput.c b/source/blender/render/intern/source/shadeinput.c
index e60a5a70a7f..6e01921a6a7 100644
--- a/source/blender/render/intern/source/shadeinput.c
+++ b/source/blender/render/intern/source/shadeinput.c
@@ -884,7 +884,10 @@ void shade_input_set_shade_texco(ShadeInput *shi)
 	float u = shi->u, v = shi->v;
 	float l = 1.0f + u + v, dl;
 	int mode = shi->mode;        /* or-ed result for all nodes */
+	int mode2 = shi->mode2;
 	short texco = shi->mat->texco;
+	const bool need_mikk_tangent = (mode & MA_NORMAP_TANG || R.flag & R_NEED_TANGENT);
+	const bool need_mikk_tangent_concrete = (mode2 & MA_TANGENT_CONCRETE) != 0;
 
 	/* calculate dxno */
 	if (shi->vlr->flag & R_SMOOTH) {
@@ -905,8 +908,8 @@ void shade_input_set_shade_texco(ShadeInput *shi)
 	}
 
 	/* calc tangents */
-	if (mode & (MA_TANGENT_V | MA_NORMAP_TANG) || R.flag & R_NEED_TANGENT) {
-		const float *tangent, *s1, *s2, *s3;
+	if (mode & (MA_TANGENT_V | MA_NORMAP_TANG) || mode2 & MA_TANGENT_CONCRETE || R.flag & R_NEED_TANGENT) {
+		const float *s1, *s2, *s3;
 		float tl, tu, tv;
 
 		if (shi->vlr->flag & R_SMOOTH) {
@@ -943,14 +946,18 @@ void shade_input_set_shade_texco(ShadeInput *shi)
 			}
 		}
 
-		if (mode & MA_NORMAP_TANG || R.flag & R_NEED_TANGENT) {
-			tangent = RE_vlakren_get_nmap_tangent(obr, shi->vlr, 0);
+		if (need_mikk_tangent || need_mikk_tangent_concrete) {
+			int j1 = shi->i1, j2 = shi->i2, j3 = shi->i3;
+			float c0[3], c1[3], c2[3];
+			int acttang = obr->actmtface;
 
-			if (tangent) {
-				int j1 = shi->i1, j2 = shi->i2, j3 = shi->i3;
-				float c0[3], c1[3], c2[3];
+			vlr_set_uv_indices(shi->vlr, &j1, &j2, &j3);
 
-				vlr_set_uv_indices(shi->vlr, &j1, &j2, &j3);
+			/* cycle through all tangent in vlakren */
+			for (int i = 0; i < MAX_MTFACE; i++) {
+				const float *tangent = RE_vlakren_get_nmap_tangent(obr, shi->vlr, i, false);
+				if (!tangent)
+					continue;
 
 				copy_v3_v3(c0, &tangent[j1 * 4]);
 				copy_v3_v3(c1, &tangent[j2 * 4]);
@@ -966,13 +973,19 @@ void shade_input_set_shade_texco(ShadeInput *shi)
 
 				/* we don't normalize the interpolated TBN tangent
 				 * corresponds better to how it's done in game engines */
-				shi->nmaptang[0] = (tl * c2[0] - tu * c0[0] - tv * c1[0]);
-				shi->nmaptang[1] = (tl * c2[1] - tu * c0[1] - tv * c1[1]);
-				shi->nmaptang[2] = (tl * c2[2] - tu * c0[2] - tv * c1[2]);
+				shi->tangents[i][0] = (tl * c2[0] - tu * c0[0] - tv * c1[0]);
+				shi->tangents[i][1] = (tl * c2[1] - tu * c0[1] - tv * c1[1]);
+				shi->tangents[i][2] = (tl * c2[2] - tu * c0[2] - tv * c1[2]);
 
 				/* the sign is the same for all 3 vertices of any
 				 * non degenerate triangle. */
-				shi->nmaptang[3] = tangent[j1 * 4 + 3];
+				shi->tangents[i][3] = tangent[j1 * 4 + 3];
+
+				if (acttang == i && need_mikk_tangent) {
+					for (int m = 0; m < 4; m++) {
+						shi->nmaptang[m] = shi->tangents[i][m];
+					}
+				}
 			}
 		}
 	}