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, 79 insertions, 49 deletions

diff --git a/source/blender/editors/space_view3d/drawmesh.c b/source/blender/editors/space_view3d/drawmesh.c
index b8d33de2e37..42ee6c0f00a 100644
--- a/source/blender/editors/space_view3d/drawmesh.c
+++ b/source/blender/editors/space_view3d/drawmesh.c
@@ -64,6 +64,7 @@
 #include "GPU_buffers.h"
 #include "GPU_extensions.h"
 #include "GPU_draw.h"
+#include "GPU_material.h"
 
 #include "ED_mesh.h"
 
@@ -207,44 +208,71 @@ static Material *give_current_material_or_def(Object *ob, int matnr)
 	return ma?ma:&defmaterial;
 }
 
-static int set_draw_settings_cached(int clearcache, int textured, MTFace *texface, int lit, Object *litob, int litmatnr, int doublesided)
+/* Icky globals, fix with userdata parameter */
+
+static struct TextureDrawState {
+	Object *ob;
+	int islit, istex;
+	int color_profile;
+	unsigned char obcol[4];
+} Gtexdraw = {NULL, 0, 0, 0, {0, 0, 0, 0}};
+
+static int set_draw_settings_cached(int clearcache, MTFace *texface, Material *ma, struct TextureDrawState gtexdraw)
 {
+	static Material *c_ma;
 	static int c_textured;
-	static int c_lit;
-	static int c_doublesided;
 	static MTFace *c_texface;
-	static Object *c_litob;
-	static int c_litmatnr;
+	static int c_backculled;
 	static int c_badtex;
+	static int c_lit;
 
+	Object *litob = NULL; //to get mode to turn off mipmap in painting mode
+	int backculled = 0;
+	int alphablend = 0;
+	int textured = 0;
+	int lit = 0;
+	
 	if (clearcache) {
-		c_textured= c_lit= c_doublesided= -1;
+		c_textured= c_lit= c_backculled= -1;
 		c_texface= (MTFace*) -1;
-		c_litob= (Object*) -1;
-		c_litmatnr= -1;
 		c_badtex= 0;
+	} else {
+		textured = gtexdraw.istex;
+		litob = gtexdraw.ob;
+	}
+
+	/* convert number of lights into boolean */
+	if (gtexdraw.islit) lit = 1;
+
+	if (ma) {
+		alphablend = ma->game.alpha_blend;
+		if (ma->mode & MA_SHLESS) lit = 0;
+		backculled = ma->game.flag & GEMAT_BACKCULL;
 	}
 
 	if (texface) {
-		lit = lit && (lit==-1 || texface->mode&TF_LIGHT);
-		textured = textured && (texface->mode&TF_TEX);
-		doublesided = texface->mode&TF_TWOSIDE;
-	} else {
-		textured = 0;
+		textured = textured && (texface->tpage);
+
+		/* no material, render alpha if texture has depth=32 */
+		if (!ma && BKE_image_has_alpha(texface->tpage))
+			alphablend = GPU_BLEND_ALPHA;
 	}
 
-	if (doublesided!=c_doublesided) {
-		if (doublesided) glDisable(GL_CULL_FACE);
-		else glEnable(GL_CULL_FACE);
+	else
+		textured = 0;
+
+	if (backculled!=c_backculled) {
+		if (backculled) glEnable(GL_CULL_FACE);
+		else glDisable(GL_CULL_FACE);
 
-		c_doublesided= doublesided;
+		c_backculled= backculled;
 	}
 
 	if (textured!=c_textured || texface!=c_texface) {
 		if (textured ) {
-			c_badtex= !GPU_set_tpage(texface, !(litob->mode & OB_MODE_TEXTURE_PAINT));
+			c_badtex= !GPU_set_tpage(texface, !(litob->mode & OB_MODE_TEXTURE_PAINT), alphablend);
 		} else {
-			GPU_set_tpage(NULL, 0);
+			GPU_set_tpage(NULL, 0, 0);
 			c_badtex= 0;
 		}
 		c_textured= textured;
@@ -252,10 +280,10 @@ static int set_draw_settings_cached(int clearcache, int textured, MTFace *texfac
 	}
 
 	if (c_badtex) lit= 0;
-	if (lit!=c_lit || litob!=c_litob || litmatnr!=c_litmatnr) {
+	if (lit!=c_lit || ma!=c_ma) {
 		if (lit) {
-			Material *ma= give_current_material_or_def(litob, litmatnr+1);
 			float spec[4];
+			if (!ma)ma= give_current_material_or_def(NULL, 0); //default material
 
 			spec[0]= ma->spec*ma->specr;
 			spec[1]= ma->spec*ma->specg;
@@ -273,22 +301,11 @@ static int set_draw_settings_cached(int clearcache, int textured, MTFace *texfac
 			glDisable(GL_COLOR_MATERIAL);
 		}
 		c_lit= lit;
-		c_litob= litob;
-		c_litmatnr= litmatnr;
 	}
 
 	return c_badtex;
 }
 
-/* Icky globals, fix with userdata parameter */
-
-static struct TextureDrawState {
-	Object *ob;
-	int islit, istex;
-	int color_profile;
-	unsigned char obcol[4];
-} Gtexdraw = {NULL, 0, 0, 0, {0, 0, 0, 0}};
-
 static void draw_textured_begin(Scene *scene, View3D *v3d, RegionView3D *rv3d, Object *ob)
 {
 	unsigned char obcol[4];
@@ -318,14 +335,14 @@ static void draw_textured_begin(Scene *scene, View3D *v3d, RegionView3D *rv3d, O
 	Gtexdraw.istex = istex;
 	Gtexdraw.color_profile = scene->r.color_mgt_flag & R_COLOR_MANAGEMENT;
 	memcpy(Gtexdraw.obcol, obcol, sizeof(obcol));
-	set_draw_settings_cached(1, 0, NULL, Gtexdraw.islit, NULL, 0, 0);
+	set_draw_settings_cached(1, NULL, NULL, Gtexdraw);
 	glShadeModel(GL_SMOOTH);
 }
 
 static void draw_textured_end(void)
 {
 	/* switch off textures */
-	GPU_set_tpage(NULL, 0);
+	GPU_set_tpage(NULL, 0, 0);
 
 	glShadeModel(GL_FLAT);
 	glDisable(GL_CULL_FACE);
@@ -347,18 +364,22 @@ static void draw_textured_end(void)
 
 static int draw_tface__set_draw_legacy(MTFace *tface, MCol *mcol, int matnr)
 {
-	if (tface && (tface->mode&TF_INVISIBLE)) return 0;
+	Material *ma= give_current_material(Gtexdraw.ob, matnr+1);
+	int validtexture=0;
+
+	if (ma && (ma->game.flag & GEMAT_INVISIBLE)) return 0;
 
-	if (tface && set_draw_settings_cached(0, Gtexdraw.istex, tface, Gtexdraw.islit, Gtexdraw.ob, matnr, TF_TWOSIDE)) {
+	validtexture = set_draw_settings_cached(0, tface, ma, Gtexdraw);
+
+	if (tface && validtexture) {
 		glColor3ub(0xFF, 0x00, 0xFF);
 		return 2; /* Don't set color */
-	} else if (tface && tface->mode&TF_OBCOL) {
+	} else if (ma && ma->shade_flag&MA_OBCOLOR) {
 		glColor3ubv(Gtexdraw.obcol);
 		return 2; /* Don't set color */
 	} else if (!mcol) {
 		if (tface) glColor3f(1.0, 1.0, 1.0);
 		else {
-			Material *ma= give_current_material(Gtexdraw.ob, matnr+1);
 			if(ma) {
 				float col[3];
 				if(Gtexdraw.color_profile) linearrgb_to_srgb_v3_v3(col, &ma->r);
@@ -375,9 +396,11 @@ static int draw_tface__set_draw_legacy(MTFace *tface, MCol *mcol, int matnr)
 }
 static int draw_tface__set_draw(MTFace *tface, MCol *mcol, int matnr)
 {
-	if (tface && (tface->mode&TF_INVISIBLE)) return 0;
+	Material *ma= give_current_material(Gtexdraw.ob, matnr+1);
 
-	if (tface && set_draw_settings_cached(0, Gtexdraw.istex, tface, Gtexdraw.islit, Gtexdraw.ob, matnr, TF_TWOSIDE)) {
+	if (ma && (ma->game.flag & GEMAT_INVISIBLE)) return 0;
+
+	if (tface && set_draw_settings_cached(0, tface, ma, Gtexdraw)) {
 		return 2; /* Don't set color */
 	} else if (tface && tface->mode&TF_OBCOL) {
 		return 2; /* Don't set color */
@@ -399,7 +422,9 @@ static void add_tface_color_layer(DerivedMesh *dm)
 
 	finalCol = MEM_mallocN(sizeof(MCol)*4*dm->getNumFaces(dm),"add_tface_color_layer");
 	for(i=0;i<dm->getNumFaces(dm);i++) {
-		if (tface && (tface->mode&TF_INVISIBLE)) {
+		Material *ma= give_current_material(Gtexdraw.ob, mface[i].mat_nr+1);
+
+		if (ma && (ma->game.flag&GEMAT_INVISIBLE)) {
 			if( mcol )
 				memcpy(&finalCol[i*4],&mcol[i*4],sizeof(MCol)*4);
 			else
@@ -409,7 +434,7 @@ static void add_tface_color_layer(DerivedMesh *dm)
 					finalCol[i*4+j].r = 255;
 				}
 		}
-		else if (tface && mface && set_draw_settings_cached(0, Gtexdraw.istex, tface, Gtexdraw.islit, Gtexdraw.ob, mface[i].mat_nr, TF_TWOSIDE)) {
+		else if (tface && mface && set_draw_settings_cached(0, tface, ma, Gtexdraw)) {
 			for(j=0;j<4;j++) {
 				finalCol[i*4+j].b = 255;
 				finalCol[i*4+j].g = 0;
@@ -493,10 +518,14 @@ static int draw_em_tf_mapped__set_draw(void *userData, int index)
 static int wpaint__setSolidDrawOptions(void *userData, int index, int *drawSmooth_r)
 {
 	Mesh *me = (Mesh*)userData;
+	Material *ma;
+
+	if (me->mface) {
+		int matnr = me->mface[index].mat_nr;
+		ma = me->mat[matnr];
+	}
 
-	if (	(me->mface && me->mface[index].flag & ME_HIDE) ||
-			(me->mtface && (me->mtface[index].mode & TF_INVISIBLE))
-	) {
+	if ( ma && (ma->game.flag & GEMAT_INVISIBLE)) {
 		return 0;
 	}
 
@@ -529,11 +558,12 @@ static void draw_mesh_text(Scene *scene, Object *ob, int glsl)
 	ddm = mesh_get_derived_deform(scene, ob, CD_MASK_BAREMESH);
 
 	for(a=0, mf=mface; a<totface; a++, tface++, mf++) {
-		int mode= tface->mode;
 		int matnr= mf->mat_nr;
 		int mf_smooth= mf->flag & ME_SMOOTH;
+		Material *mat = me->mat[matnr];
+		int mode= mat->game.flag;
 
-		if (!(mf->flag&ME_HIDE) && !(mode&TF_INVISIBLE) && (mode&TF_BMFONT)) {
+		if (!(mode&GEMAT_INVISIBLE) && (mode&GEMAT_TEXT)) {
 			float v1[3], v2[3], v3[3], v4[3];
 			char string[MAX_PROPSTRING];
 			int characters, i, glattrib= -1, badtex= 0;
@@ -549,7 +579,7 @@ static void draw_mesh_text(Scene *scene, Object *ob, int glsl)
 				}
 			}
 			else {
-				badtex = set_draw_settings_cached(0, Gtexdraw.istex, tface, Gtexdraw.islit, Gtexdraw.ob, matnr, TF_TWOSIDE);
+				badtex = set_draw_settings_cached(0, tface, mat, Gtexdraw);
 				if (badtex) {
 					if (mcol) mcol+=4;
 					continue;
@@ -578,7 +608,7 @@ static void draw_mesh_text(Scene *scene, Object *ob, int glsl)
 				glNormal3fv(nor);
 			}
 
-			GPU_render_text(tface, tface->mode, string, characters,
+			GPU_render_text(tface, mode, string, characters,
 				(unsigned int*)mcol, v1, v2, v3, (mf->v4? v4: NULL), glattrib);
 		}
 		if (mcol) {