engine: implement loading luma in half-life

common/com_image.h

@@ -70,6 +70,7 @@ typedef enum
 	IL_OVERVIEW	= BIT(6),	// overview required some unque operations
 	IL_LOAD_PLAYER_DECAL = BIT(7), // special mode for player decals
 	IL_KTX2_RAW = BIT(8), // renderer can consume raw KTX2 files (e.g. ref_vk)
+	IL_ALLOW_WAD3_LUMA = BIT(9), // allow usage of luma textures in wad3 (tilde textures)
 } ilFlags_t;
 
 // goes into rgbdata_t->encode

engine/common/imagelib/img_wad.c

@@ -358,6 +358,25 @@ qboolean Image_LoadLMP( const char *name, const byte *buffer, fs_offset_t filesi
 	return Image_AddIndexedImageToPack( fin, image.width, image.height );
 }
 
+static int Image_FindBestBlack( const uint *pal )
+{
+	int min_color = 32;
+	int best_black = -1;
+
+	for( int i = 0; i < 256; i++ )
+	{
+		int color = pal[i] & 0xFFFFFF;
+
+		if( color < min_color )
+		{
+			min_color = color;
+			best_black = i;
+		}
+	}
+
+	return best_black;
+}
+
 /*
 =============
 Image_LoadMIP
@@ -416,29 +435,27 @@ qboolean Image_LoadMIP( const char *name, const byte *buffer, fs_offset_t filesi
 		}
 		else
 		{
-			int	pal_type;
-
 			// NOTE: we can have luma-pixels if quake1 texture
 			// converted into the hl texture but palette leave unchanged
 			// this is a good reason for using fullbright pixels
-			pal_type = Image_ComparePalette( pal );
-
-			// check for luma pixels (but ignore liquid textures because they have no lightmap)
-			if( mip.name[0] != '*' && mip.name[0] != '!' && pal_type == PAL_QUAKE1 )
-			{
-				for( i = 0; i < image.width * image.height; i++ )
-				{
-					if( fin[i] > 224 )
-					{
-						SetBits( image.flags, IMAGE_HAS_LUMA );
-						image.black_pixel = 0;
-						break;
-					}
-				}
-			}
+			const int pal_type = Image_ComparePalette( pal );
 
 			if( pal_type == PAL_QUAKE1 )
 			{
+				// check for luma pixels (but ignore liquid textures because they have no lightmap)
+				if( mip.name[0] != '*' && mip.name[0] != '!' )
+				{
+					for( i = 0; i < image.width * image.height; i++ )
+					{
+						if( fin[i] > 224 )
+						{
+							SetBits( image.flags, IMAGE_HAS_LUMA );
+							image.black_pixel = 0;
+							break;
+						}
+					}
+				}
+
 				SetBits( image.flags, IMAGE_QUAKEPAL );
 
 				// if texture was converted from quake to half-life with no palette changes
@@ -449,11 +466,30 @@ qboolean Image_LoadMIP( const char *name, const byte *buffer, fs_offset_t filesi
 			{
 				// half-life mips need texgamma applied
 				rendermode = LUMP_TEXGAMMA;
+
+				// three checks here: check if we can load luma, check the texture name and, finally,
+				// validate that palette isn't NULL
+				if( Image_CheckFlag( IL_ALLOW_WAD3_LUMA )
+					&& ( mip.name[0] == '~' || ( mip.name[0] == '+' && isdigit( mip.name[1] ) && mip.name[2] == '~' ))
+					&& pal != NULL )
+				{
+					SetBits( image.flags, IMAGE_HAS_LUMA );
+				}
 			}
 		}
 
 		Image_GetPaletteLMP( pal, rendermode );
 		image.d_currentpal[255] &= 0xFFFFFF;
+
+		if( rendermode == LUMP_TEXGAMMA && FBitSet( image.flags, IMAGE_HAS_LUMA ))
+		{
+			// thanks to Unkle Mike for an idea of looking best black pixel
+			image.black_pixel = Image_FindBestBlack( image.d_currentpal );
+
+			// failed to find good pixel, refuse to load luma
+			if( image.black_pixel == -1 )
+				ClearBits( image.flags, IMAGE_HAS_LUMA );
+		}
 	}
 	else if( image.hint != IL_HINT_HL && filesize >= (int)sizeof(mip) + ((pixels * 85)>>6))
 	{
@@ -466,7 +502,7 @@ qboolean Image_LoadMIP( const char *name, const byte *buffer, fs_offset_t filesi
 
 		// check for luma and alpha pixels
 		// don't apply luma to water surfaces because they have no lightmap
-		if( !image.custom_palette && mip.name[0] != '*' && mip.name != '!' )
+		if( !image.custom_palette && mip.name[0] != '*' && mip.name[0] != '!' )
 		{
 			for( i = 0; i < image.width * image.height; i++ )
 			{

engine/common/mod_bmodel.c

@@ -2583,6 +2583,7 @@ static void Mod_LoadTextureData( model_t *mod, dbspmodel_t *bmod, int textureInd
 	const mip_t *mipTex = Mod_GetMipTexForTexture( bmod, textureIndex );
 	const qboolean usesCustomPalette = Mod_CalcMipTexUsesCustomPalette( mod, bmod, textureIndex );
 	const qboolean iswater = Mod_LooksLikeWaterTexture( mipTex->name );
+	const uint texture_force_flags = r_allow_wad3_luma.value ? IL_ALLOW_WAD3_LUMA : 0;
 
 	// check for multi-layered sky texture (quake1 specific)
 	if( bmod->isworld && Q_strncmp( mipTex->name, "sky", 3 ) == 0 && ( mipTex->width / mipTex->height ) == 2 )
@@ -2633,6 +2634,7 @@ static void Mod_LoadTextureData( model_t *mod, dbspmodel_t *bmod, int textureInd
 #if !XASH_DEDICATED
 			if( !Host_IsDedicated( ) && pic != NULL )
 			{
+				Image_SetForceFlags( texture_force_flags );
 				texture->gl_texturenum = ref.dllFuncs.GL_LoadTextureFromBuffer( texpath, pic, txFlags, false );
 				FS_FreeImage( pic );
 			}
@@ -2652,6 +2654,7 @@ static void Mod_LoadTextureData( model_t *mod, dbspmodel_t *bmod, int textureInd
 		const size_t size = Mod_CalculateMipTexSize( mipTex, usesCustomPalette );
 
 		Q_snprintf( texName, sizeof( texName ), "#%s:%s.mip", loadstat.name, mipTex->name );
+		Image_SetForceFlags( texture_force_flags );
 		texture->gl_texturenum = ref.dllFuncs.GL_LoadTexture( texName, (byte *)mipTex, size, txFlags );
 	}
 
@@ -2684,6 +2687,8 @@ static void Mod_LoadTextureData( model_t *mod, dbspmodel_t *bmod, int textureInd
 
 		Q_snprintf( texName, sizeof( texName ), "#%s:%s_luma.mip", loadstat.name, mipTex->name );
 
+		Image_SetForceFlags( texture_force_flags );
+
 		if( mipTex->offsets[0] > 0 )
 		{
 			const size_t size = Mod_CalculateMipTexSize( mipTex, usesCustomPalette );

engine/common/mod_local.h

@@ -129,11 +129,12 @@ typedef struct world_static_s
 } world_static_t;
 
 #ifndef REF_DLL
-extern world_static_t	world;
-extern poolhandle_t     com_studiocache;
-extern convar_t		mod_studiocache;
-extern convar_t		r_wadtextures;
-extern convar_t		r_showhull;
+extern world_static_t world;
+extern poolhandle_t   com_studiocache;
+extern convar_t       mod_studiocache;
+extern convar_t       r_wadtextures;
+extern convar_t       r_showhull;
+extern convar_t       r_allow_wad3_luma;
 extern const mclipnode16_t box_clipnodes16[6];
 extern const mclipnode32_t box_clipnodes32[6];
 

engine/common/model.c

@@ -31,6 +31,7 @@ poolhandle_t      com_studiocache;		// cache for submodels
 CVAR_DEFINE( mod_studiocache, "r_studiocache", "1", FCVAR_ARCHIVE, "enables studio cache for speedup tracing hitboxes" );
 CVAR_DEFINE_AUTO( r_wadtextures, "0", 0, "completely ignore textures in the bsp-file if enabled" );
 CVAR_DEFINE_AUTO( r_showhull, "0", 0, "draw collision hulls 1-3" );
+CVAR_DEFINE_AUTO( r_allow_wad3_luma, "0", FCVAR_ARCHIVE, "allow usage of luma textures in wad3 (tilde textures)" );
 
 /*
 ===============================================================================
@@ -142,6 +143,7 @@ void Mod_Init( void )
 	Cvar_RegisterVariable( &mod_studiocache );
 	Cvar_RegisterVariable( &r_wadtextures );
 	Cvar_RegisterVariable( &r_showhull );
+	Cvar_RegisterVariable( &r_allow_wad3_luma );
 
 	Cmd_AddCommand( "mapstats", Mod_PrintWorldStats_f, "show stats for currently loaded map" );
 	Cmd_AddCommand( "modellist", Mod_Modellist_f, "display loaded models list" );