TexFace to Material Settings big patch

Summary:
========
The idea here is to move the texface options into the material panel.
For images with the change please visit:
http://code.blender.org/index.php/2011/09/bge-material-texface-changes

1 - Some of the legacy problems 2.49 and 2.5x has with the texface system:
==========================================================================
1.1) Shadow, Bilboard and Halo are mutual exclusive (in the code), yet you can
select a face to be more than one mode.
1.2) Sort only works for blend Alpha yet it's an option regardless of the
Transparency Blend you pick.
1.3) Shared doesn't affect anything in BGE.
1.4) ObColor only works for Text objects (old bitmap texts) when using Texture
Face Materials. (not address yet, I so far ignored obcolor)

2 - Notes:
============
2.1) Now "Use Face Textures" in material Option panel will work in Multitexture
even if there is no texture channel.

2.2) In FaceTexture mode it will use TexFace all the time, even if you don't
check the "Use Texture Face" option in the UI. It's a matter of decision, since
the code for either way is there. I decided by the solution that makes the
creation of a material fast - in this mode the user doesn't need to mess with
textures or this "Use Texture Face" option at all. I'm not strong in my opinion
here. But I think if we don't have this then what is the point of the Texture
Face mode?

2.3) I kept references for tface only when we need the image, UV or the tiling
setting. It should help later when/if we split the Image and UV layers from the
tface struct  (Campbell and Brecht proposal).

3 - Changes in a Nutshell:
==========================
3.1) "Texture Face" panel (in the Mesh/Object Data panel) no longer exists. Those settings are all part of the material properties, visible when Game Render is set.

3.2) "Texture Face" Shading mode (in the Render panel) is now called “Single Texture”, it needs a material for special settings (e.g. Billboard, Alpha Sort, …).

3.3) New options in the Material Panel
* Shadeless option in the Material panel is now supported for all three Shading modes.
* Physics is now toggleable, this is the old Collision option.
* Two Side (on) is now called Back Culling (off).
* Alpha Sort is one of the Alpha options, together (and mutually exclusive) to Alpha Blend, Alpha Clip, Add and Opaque (i.e. solid).
* Shadow, Billboard and Halo are grouped in the “Face Orientation” property.
* "Face Textures" and "Face Textures Alpha" (under Options) can be used for all but GLSL shading mode (to be supported in GLSL eventually).
* The backend in the game engine is still the same as before. The only changes are in the interface and in the way you need to think your materials. The bottomline is: It’s no longer possible to share materials between faces that do not share the same game properties.

4 - Acknowledgment:
==================
Mike Pan for the design discussions, and testing along the whole development process.
Vitor Balbio for the first hands-on code with the interface changes. That helped me a lot to push me into work on that.
Benoit Bolsee and Brecht van Lommel for patch review (* no one reviewed the whole patch, or the latest iteractions, so I still hold liability for any problems).
Blender artists that gave feedback and helped testing the patch.

Patch review and original documentation can be found here:
http://wiki.blender.org/index.php/User:Dfelinto/TexFace
http://codereview.appspot.com/4289041/

1 files changed, 485 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/material.c b/source/blender/blenkernel/intern/material.c
index 2a9e786d139..956d7b01b3b 100644
--- a/source/blender/blenkernel/intern/material.c
+++ b/source/blender/blenkernel/intern/material.c
@@ -43,6 +43,9 @@
 #include "DNA_curve_types.h"
 #include "DNA_material_types.h"
 #include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+#include "DNA_customdata_types.h"
+#include "DNA_ID.h"
 #include "DNA_meta_types.h"
 #include "DNA_node_types.h"
 #include "DNA_object_types.h"
@@ -56,6 +59,7 @@
 #include "BKE_displist.h"
 #include "BKE_global.h"
 #include "BKE_icons.h"
+#include "BKE_image.h"
 #include "BKE_library.h"
 #include "BKE_main.h"
 #include "BKE_material.h"
@@ -188,6 +192,10 @@ void init_material(Material *ma)
 	ma->vol.ms_diff = 1.f;
 	ma->vol.ms_intensity = 1.f;
 	
+	ma->game.flag=0;
+	ma->game.alpha_blend=0;
+	ma->game.face_orientation=0;
+	
 	ma->mode= MA_TRACEBLE|MA_SHADBUF|MA_SHADOW|MA_RAYBIAS|MA_TANGENT_STR|MA_ZTRANSP;
 	ma->shade_flag= MA_APPROX_OCCLUSION;
 	ma->preview = NULL;
@@ -1468,3 +1476,480 @@ void paste_matcopybuf(Material *ma)
 
 	ma->nodetree= ntreeCopyTree(matcopybuf.nodetree);
 }
+
+
+/*********************** texface to material convert functions **********************/
+/* encode all the TF information into a single int */
+int encode_tfaceflag(MTFace *tf, int convertall)
+{
+	/* calculate the flag */
+	int flag = tf->mode;
+
+	/* options that change the material offline render */	
+	if (!convertall) {
+		flag &= ~TF_OBCOL;
+	}
+
+	/* clean flags that are not being converted */
+	flag &= ~TF_TEX;
+	flag &= ~TF_SHAREDVERT;
+	flag &= ~TF_SHAREDCOL;
+	flag &= ~TF_CONVERTED;
+
+	/* light tface flag is ignored in GLSL mode */
+	flag &= ~TF_LIGHT;
+	
+	/* 15 is how big the flag can be - hardcoded here and in decode_tfaceflag() */
+	flag |= tf->transp << 15;
+	
+	/* increase 1 so flag 0 is different than no flag yet */
+	return flag + 1;
+}
+
+/* set the material options based in the tface flag */
+void decode_tfaceflag(Material *ma, int flag, int convertall)
+{
+	int alphablend;	
+	GameSettings *game= &ma->game;
+
+	/* flag is shifted in 1 to make 0 != no flag yet (see encode_tfaceflag) */
+	flag -= 1;
+
+	alphablend = flag >> 15; //encoded in the encode_tfaceflag function
+	(*game).flag = 0;
+	
+	/* General Material Options */
+	if ((flag & TF_DYNAMIC)==0) (*game).flag	|= GEMAT_NOPHYSICS;
+	
+	/* Material Offline Rendering Properties */
+	if (convertall) {
+		if (flag & TF_OBCOL) ma->shade_flag |= MA_OBCOLOR;
+	}
+	
+	/* Special Face Properties */
+	if ((flag & TF_TWOSIDE)==0) (*game).flag |= GEMAT_BACKCULL;
+	if (flag & TF_INVISIBLE)(*game).flag |= GEMAT_INVISIBLE;
+	if (flag & TF_BMFONT) (*game).flag |= GEMAT_TEXT;
+	
+	/* Face Orientation */
+	if (flag & TF_BILLBOARD) (*game).face_orientation |= GEMAT_HALO;
+	else if (flag & TF_BILLBOARD2) (*game).face_orientation |= GEMAT_BILLBOARD;
+	else if (flag & TF_SHADOW) (*game).face_orientation |= GEMAT_SHADOW;
+	
+	/* Alpha Blend */
+	if (flag & TF_ALPHASORT && ELEM(alphablend, TF_ALPHA, TF_ADD)) (*game).alpha_blend = GEMAT_ALPHA_SORT;
+	else if (alphablend & TF_ALPHA) (*game).alpha_blend = GEMAT_ALPHA;
+	else if (alphablend & TF_ADD) (*game).alpha_blend = GEMAT_ADD;
+	else if (alphablend & TF_CLIP) (*game).alpha_blend = GEMAT_CLIP;
+}
+
+/* boolean check to see if the mesh needs a material */
+int check_tfaceneedmaterial(int flag)
+{
+	// check if the flags we have are not deprecated != than default material options
+	// also if only flags are visible and collision see if all objects using this mesh have this option in physics
+
+	/* flag is shifted in 1 to make 0 != no flag yet (see encode_tfaceflag) */
+	flag -=1;
+
+	// deprecated flags
+	flag &= ~TF_OBCOL;
+	flag &= ~TF_SHAREDVERT;
+	flag &= ~TF_SHAREDCOL;
+
+	/* light tface flag is ignored in GLSL mode */
+	flag &= ~TF_LIGHT;
+	
+	// automatic detected if tex image has alpha
+	flag &= ~(TF_ALPHA << 15);
+	// automatic detected if using texture
+	flag &= ~TF_TEX;
+
+	// settings for the default NoMaterial
+	if (flag == TF_DYNAMIC)
+		return 0;
+
+	else
+		return 1;
+}
+
+/* return number of digits of an integer */
+// XXX to be optmized or replaced by an equivalent blender internal function
+int integer_getdigits(int number)
+{
+	int i=0;
+	if (number == 0) return 1;
+
+	while (number != 0){
+		number = (int)(number/10);
+		i++;
+	}
+	return i;
+}
+
+void calculate_tface_materialname(char *matname, char *newname, int flag)
+{
+	// if flag has only light and collision and material matches those values
+	// you can do strcpy(name, mat_name);
+	// otherwise do:
+	int digits = integer_getdigits(flag);
+	/* clamp the old name, remove the MA prefix and add the .TF.flag suffix
+	e.g. matname = "MALoooooooooooooongName"; newname = "Loooooooooooooon.TF.2" */
+	sprintf(newname, "%.*s.TF.%0*d", MAX_ID_NAME-(digits+5), matname, digits, flag);
+}
+
+/* returns -1 if no match */
+int mesh_getmaterialnumber(Mesh *me, Material *ma) {
+	int a;
+
+	for (a=0; a<me->totcol; a++)
+		if (me->mat[a] == ma)
+			return a;
+
+	return -1;
+}
+
+/* append material */
+int mesh_addmaterial(Mesh *me, Material *ma)
+{
+	material_append_id(&me->id, NULL);
+	me->mat[me->totcol-1]= ma;
+
+	id_us_plus(&ma->id);
+
+	return me->totcol-1;
+}
+
+Material *materialbyname(Main *main, char *name)
+{
+	Material *mat = NULL;
+	for (mat=main->mat.first;mat;mat=mat->id.next) {
+		if (strcmp(mat->id.name, name)==0)
+			return mat; 
+	}
+	return NULL;
+}
+
+void set_facetexture_flags(Material *ma, Image *image)
+{
+	if(image) {
+		ma->mode |= MA_FACETEXTURE;
+		/* we could check if the texture has alpha, but then more meshes sharing the same
+		 * material may need it. Let's make it simple. */
+		if(BKE_image_has_alpha(image))
+			ma->mode |= MA_FACETEXTURE_ALPHA;
+	}
+}
+
+/* returns material number */
+int convert_tfacenomaterial(Main *main, Mesh *me, MTFace *tf, int flag)
+{
+	Material *ma;
+	char name[MAX_ID_NAME];
+	int mat_nr= -1;
+	
+	/* new material, the name uses the flag*/
+	sprintf(name, "MAMaterial.TF.%0*d", integer_getdigits(flag), flag);
+	
+	if ((ma=materialbyname(main, name))) {
+		mat_nr = mesh_getmaterialnumber(me, ma);
+		/* assign the material to the mesh */
+		if(mat_nr == -1) mat_nr= mesh_addmaterial(me, ma);
+
+		/* if needed set "Face Textures [Alpha]" Material options */
+		set_facetexture_flags(ma, tf->tpage);
+	}
+	/* create a new material */
+	else {
+		ma=add_material(name+2);
+
+		if(ma){
+			printf("TexFace Convert: Material \"%s\" created.\n", name+2);
+			mat_nr= mesh_addmaterial(me, ma);
+			
+			/* if needed set "Face Textures [Alpha]" Material options */
+			set_facetexture_flags(ma, tf->tpage);
+
+			decode_tfaceflag(ma, flag, 1);
+			// the final decoding will happen after, outside the main loop
+			// for now store the flag into the material and change light/tex/collision 
+			// store the flag as a negative number
+			ma->game.flag = -flag;
+			id_us_min((ID *)ma);	
+		}
+		else printf("Error: Unable to create Material \"%s\" for Mesh \"%s\".", name+2, me->id.name+2);
+	}
+
+	/* set as converted, no need to go bad to this face */
+	tf->mode |= TF_CONVERTED;	
+	return mat_nr;
+}
+
+/* Function to fully convert materials */
+void convert_tfacematerial(Main *main, Material *ma)
+{
+	Mesh *me;
+	Material *mat_new;
+	MFace *mf;
+	MTFace *tf;
+	int flag, index;
+	int a, mat_nr;
+	CustomDataLayer *cdl;
+	char name[MAX_ID_NAME];
+
+	for(me=main->mesh.first; me; me=me->id.next){
+		/* check if this mesh uses this material */
+		for(a=0;a<me->totcol;a++)
+			if(me->mat[a] == ma) break;
+			
+		/* no material found */
+		if (a == me->totcol) continue;
+
+		/* get the active tface layer */
+		index= CustomData_get_active_layer_index(&me->fdata, CD_MTFACE);
+		cdl= (index == -1)? NULL: &me->fdata.layers[index];
+		if (!cdl) continue;
+
+		/* loop over all the faces and stop at the ones that use the material*/
+		for(a=0, mf=me->mface; a<me->totface; a++, mf++) {
+			if(me->mat[(int)mf->mat_nr] != ma) continue;
+
+			/* texface data for this face */
+			tf = ((MTFace*)cdl->data) + a;
+			flag = encode_tfaceflag(tf, 1);
+
+			/* the name of the new material */
+			calculate_tface_materialname(ma->id.name, (char *)&name, flag);
+
+			if ((mat_new=materialbyname(main, name))) {
+				/* material already existent, see if the mesh has it */
+				mat_nr = mesh_getmaterialnumber(me, mat_new);
+				/* material is not in the mesh, add it */
+				if(mat_nr == -1) mat_nr= mesh_addmaterial(me, mat_new);
+			}
+			/* create a new material */
+			else {
+				mat_new=copy_material(ma);
+				if(mat_new){
+					/* rename the material*/
+					strcpy(mat_new->id.name, name);
+					id_us_min((ID *)mat_new);	
+
+					mat_nr= mesh_addmaterial(me, mat_new);
+					decode_tfaceflag(mat_new, flag, 1);
+				}
+				else {
+					printf("Error: Unable to create Material \"%s\" for Mesh \"%s.", name+2, me->id.name+2);
+					mat_nr = mf->mat_nr;
+					continue;
+				}
+			}
+			
+			/* if the material has a texture but no texture channel
+			 * set "Face Textures [Alpha]" Material options 
+			 * actually we need to run it always, because of old behavior
+			 * of using face texture if any texture channel was present (multitex) */
+			//if((!mat_new->mtex[0]) && (!mat_new->mtex[0]->tex))
+			set_facetexture_flags(mat_new, tf->tpage);
+
+			/* set the material number to the face*/
+			mf->mat_nr = mat_nr;
+		}
+		/* remove material from mesh */
+		for(a=0;a<me->totcol;)
+			if(me->mat[a] == ma) material_pop_id(&me->id, a, 1);else a++;
+	}
+}
+
+int do_version_tface(Main *main, int fileload)
+{
+	Mesh *me;
+	Material *ma;
+	MFace *mf;
+	MTFace *tf;
+	CustomDataLayer *cdl;
+	int a;
+	int flag;
+	int index;
+	int nummat;
+
+ 	/* sometimes mesh has no materials but will need a new one. In those
+	 * cases we need to ignore the mf->mat_nr and only look at the face
+	 * mode because it can be zero as unitialized or the 1st created material
+	 */
+	int nomaterialslots;
+
+	/* alert to user to check the console */
+	int nowarning = 1;
+
+	/* mark all the materials to convertion with a flag
+	 * if there is tface create a complete flag for that storing in flag
+	 * if there is tface and flag > 0: creates a new flag based on this face
+	 * if flags are different set flag to -1  
+	 */
+	
+	/* 1st part: marking mesh materials to update */
+	for(me=main->mesh.first; me; me=me->id.next){
+		if (me->id.lib) continue;
+
+		/* get the active tface layer */
+		index= CustomData_get_active_layer_index(&me->fdata, CD_MTFACE);
+		cdl= (index == -1)? NULL: &me->fdata.layers[index];
+		if (!cdl) continue;
+
+		nomaterialslots = (me->totcol==0?1:0);
+		
+		/* loop over all the faces*/
+		for(a=0, mf=me->mface; a<me->totface; a++, mf++) {
+			/* texface data for this face */
+			tf = ((MTFace*)cdl->data) + a;
+
+			/* conversion should happen only once */
+			if (fileload)
+				tf->mode &= ~TF_CONVERTED;
+			else {
+				if((tf->mode & TF_CONVERTED)) continue;
+				else tf->mode |= TF_CONVERTED;
+			}
+			
+			/* no material slots */
+			if(nomaterialslots) {
+				flag = encode_tfaceflag(tf, 1);
+				
+				/* create/find a new material and assign to the face */
+				if (check_tfaceneedmaterial(flag))
+					mf->mat_nr= convert_tfacenomaterial(main, me, tf, flag);
+					
+			/* else mark them as no-material to be reverted to 0 later */
+				else
+					mf->mat_nr = -1;
+			}
+			else if(mf->mat_nr < me->totcol) {
+				ma= me->mat[(int)mf->mat_nr];
+				
+				/* no material create one if necessary */
+				if(!ma) {
+					/* find a new material and assign to the face */
+					flag = encode_tfaceflag(tf, 1);
+
+					/* create/find a new material and assign to the face */
+					if (check_tfaceneedmaterial(flag))
+						mf->mat_nr= convert_tfacenomaterial(main, me, tf, flag);
+
+					continue;
+				}
+
+				/* we can't read from this if it comes from a library,
+				 * at doversion time: direct_link might not have happened on it,
+				 * so ma->mtex is not pointing to valid memory yet.
+				 * later we could, but it's better not */
+				else if(ma->id.lib)
+					continue;
+				
+				/* material already marked as disputed */
+				else if(ma->game.flag == -99999)
+					continue;
+
+				/* found a material */
+				else {
+					flag = encode_tfaceflag(tf, ((fileload)?0:1));
+
+					/* first time changing this material */
+					if (ma->game.flag == 0)
+						ma->game.flag= -flag;
+			
+					/* mark material as disputed */
+					else if (ma->game.flag != -flag) {
+						ma->game.flag = -99999;
+						continue;
+					}
+			
+					/* material ok so far */
+					else {
+						ma->game.flag = -flag;
+						
+						/* some people uses multitexture with TexFace by creating a texture
+						 * channel which not necessarly the tf->tpage image. But the game engine
+						 * was enabling it. Now it's required to set "Face Texture [Alpha] in the
+						 * material settings. */
+						if(!fileload)
+							set_facetexture_flags(ma, tf->tpage);
+					}
+				}
+			}
+			else
+				continue;
+		}
+
+		/* if we didn't have material slot and now we do, we need to
+		 * make sure the materials are correct */
+		if(nomaterialslots) {
+			if (me->totcol>0) {
+				for(a=0, mf=me->mface; a<me->totface; a++, mf++) {
+					if (mf->mat_nr == -1) {
+						/* texface data for this face */
+						tf = ((MTFace*)cdl->data) + a;
+						mf->mat_nr= convert_tfacenomaterial(main, me, tf, encode_tfaceflag(tf, 1));
+					}
+				}
+			} else {
+				for(a=0, mf=me->mface; a<me->totface; a++, mf++)
+					mf->mat_nr=0;
+			}
+		}
+
+	}
+	
+	/* 2nd part - conversion */
+	/* skip library files */
+
+	/* we shouldn't loop through the materials created in the loop. make the loop stop at its original length) */
+	for (ma= main->mat.first, a=0; ma; ma= ma->id.next, a++) {
+		if (ma->id.lib) continue;
+
+		/* disputed material */
+		if (ma->game.flag == -99999) {
+			ma->game.flag = 0;
+			if (fileload) {
+				printf("Warning: material \"%s\" skipped - to convert old game texface to material go to the Help menu.\n", ma->id.name+2);
+				nowarning = 0;
+			}
+			else
+				convert_tfacematerial(main, ma);
+			continue;	
+		}
+	
+		/* no conflicts in this material - 90% of cases
+		 * convert from tface system to material */
+		else if (ma->game.flag < 0){
+			decode_tfaceflag(ma, -(ma->game.flag), 1);
+
+			/* material is good make sure all faces using
+			 * this material are set to converted */
+			if (fileload) {
+				for(me=main->mesh.first; me; me=me->id.next){
+					/* check if this mesh uses this material */
+					for(a=0;a<me->totcol;a++)
+						if(me->mat[a] == ma) break;
+						
+					/* no material found */
+					if (a == me->totcol) continue;
+			
+					/* get the active tface layer */
+					index= CustomData_get_active_layer_index(&me->fdata, CD_MTFACE);
+					cdl= (index == -1)? NULL: &me->fdata.layers[index];
+					if (!cdl) continue;
+			
+					/* loop over all the faces and stop at the ones that use the material*/
+					for(a=0, mf=me->mface; a<me->totface; a++, mf++) {
+						if(me->mat[(int)mf->mat_nr] != ma) continue;
+						else tf->mode |= TF_CONVERTED;
+					}
+				}
+			}
+		}
+	}
+
+	return nowarning;
+}
+