Lightmapped water

Documentation/extensions/litwater.md

@@ -0,0 +1,19 @@
+## Lightmapped water
+
+Xash3D FWGS supports lightmapped water, as an extension. It adds three new cvars and new worldspawn key values.
+
+### For level designers:
+
+If you're a level designer and intend to make your level to have lightmapped water, you can put these keyvalues to worldspawn entity description (always first entity in entities list):
+
+| Key                    | Value   | Description |
+| ---------------------- | ------- | ----------- |
+| `_litwater`            | integer | Set to any non-zero value to enable lightmapped water. Overrides `gl_litwater_force` cvar value. |
+| `_litwater_minlight`   | integer | Minimal lightmap value water surface will receive. Helps to avoid too dark areas when water isn't properly lit. If not set, defaults to zero. |
+| `_litwater_scale`      | float   | Scales up lightmap value for water surfaces. If not set, defaults to 1.0. |
+
+### For players:
+
+Some of the maps already have computed lightmap for water surfaces and sometimes water has been properly lit but the support hasn't been declared by the level designer.
+
+As a player, you can enable it in `Video options` menu or through console with `gl_litwater_force` cvar. There are also `gl_litwater_minlight` and `gl_litwater_scale` cvars that function similar to keys above. The default values has been set to `192` and `1.25` respectively to slightly avoid issues with maps that wasn't intended to have lightmapped water.

engine/common/mod_bmodel.c

@@ -1677,9 +1677,10 @@ static void Mod_SetupSubmodels( model_t *mod, dbspmodel_t *bmod )
 			// mark models that have origin brushes
 			if( !VectorIsNull( bm->origin ))
 				SetBits( mod->flags, MODEL_HAS_ORIGIN );
+
 #ifdef HACKS_RELATED_HLMODS
 			// c2a1 doesn't have origin brush it's just placed at center of the level
-			if( !Q_stricmp( name, "maps/c2a1.bsp" ) && ( i == 11 ))
+			if( i == 11 && !Q_stricmp( name, "maps/c2a1.bsp" ))
 				SetBits( mod->flags, MODEL_HAS_ORIGIN );
 #endif
 		}
@@ -1835,6 +1836,8 @@ static void Mod_LoadEntities( model_t *mod, dbspmodel_t *bmod )
 	world.generator[0] = '\0';
 	world.compiler[0] = '\0';
 	world.message[0] = '\0';
+	world.litwater_minlight = -1;
+	world.litwater_scale = -1.0f;
 	bmod->wadlist.count = 0;
 
 	// parse all the wads for loading textures in right ordering
@@ -1893,6 +1896,15 @@ static void Mod_LoadEntities( model_t *mod, dbspmodel_t *bmod )
 				Q_strncpy( world.compiler, token, sizeof( world.compiler ));
 			else if( !Q_stricmp( keyname, "generator" ) || !Q_stricmp( keyname, "_generator" ))
 				Q_strncpy( world.generator, token, sizeof( world.generator ));
+			else if( !Q_stricmp( keyname, "_litwater" ))
+			{
+				if( Q_atoi( token ) != 0 )
+					SetBits( world.flags, FWORLD_HAS_LITWATER );
+			}
+			else if( !Q_stricmp( keyname, "_litwater_minlight" ))
+				world.litwater_minlight = Q_atoi( token );
+			else if( !Q_stricmp( keyname, "_litwater_scale" ))
+				world.litwater_scale = Q_atof( token );
 		}
 		return;	// all done
 	}

engine/common/mod_local.h

@@ -119,6 +119,10 @@ typedef struct world_static_s
 	// Potentially Hearable Set
 	byte   *compressed_phs;
 	size_t *phsofs;
+
+	// lightmapped water extra info
+	float litwater_scale;
+	int   litwater_minlight;
 } world_static_t;
 
 #ifndef REF_DLL

engine/ref_api.h

@@ -80,10 +80,11 @@ GNU General Public License for more details.
 #define MODEL_CLIENT		BIT( 30 )	// client sprite
 
 // goes into world.flags
-#define FWORLD_SKYSPHERE		BIT( 0 )
-#define FWORLD_CUSTOM_SKYBOX		BIT( 1 )
-#define FWORLD_WATERALPHA		BIT( 2 )
-#define FWORLD_HAS_DELUXEMAP		BIT( 3 )
+#define FWORLD_SKYSPHERE     BIT( 0 )
+#define FWORLD_CUSTOM_SKYBOX BIT( 1 )
+#define FWORLD_WATERALPHA    BIT( 2 )
+#define FWORLD_HAS_DELUXEMAP BIT( 3 )
+#define FWORLD_HAS_LITWATER  BIT( 4 )
 
 // special rendermode for screenfade modulate
 // (probably will be expanded at some point)

ref/gl/gl_local.h

@@ -494,11 +494,10 @@ void R_ClearSkyBox( void );
 void R_DrawSkyBox( void );
 void R_DrawClouds( void );
 void R_UnloadSkybox( void );
-void EmitWaterPolys( msurface_t *warp, qboolean reverse );
 void R_InitRipples( void );
 void R_ResetRipples( void );
 void R_AnimateRipples( void );
-void R_UploadRipples( texture_t *image );
+float R_UploadRipples( texture_t *image );
 
 //#include "vid_common.h"
 
@@ -749,6 +748,9 @@ extern convar_t	gl_test;		// cvar to testify new effects
 extern convar_t	gl_msaa;
 extern convar_t	gl_stencilbits;
 extern convar_t	gl_overbright;
+extern convar_t	gl_litwater_force;
+extern convar_t	gl_litwater_minlight;
+extern convar_t	gl_litwater_scale;
 
 extern convar_t	r_lighting_extended;
 extern convar_t	r_lighting_ambient;

ref/gl/gl_opengl.c

@@ -20,6 +20,9 @@ CVAR_DEFINE_AUTO( gl_test, "0", 0, "engine developer cvar for quick testing new
 CVAR_DEFINE_AUTO( gl_msaa, "1", FCVAR_GLCONFIG, "enable or disable multisample anti-aliasing" );
 CVAR_DEFINE_AUTO( gl_stencilbits, "8", FCVAR_GLCONFIG|FCVAR_READ_ONLY, "pixelformat stencil bits (0 - auto)" );
 CVAR_DEFINE_AUTO( gl_overbright, "1", FCVAR_GLCONFIG, "overbrights" );
+CVAR_DEFINE_AUTO( gl_litwater_force, "0", FCVAR_GLCONFIG, "force enable lightmapped water, even if support not declared in the map" );
+CVAR_DEFINE_AUTO( gl_litwater_minlight, "192", FCVAR_GLCONFIG, "minimal light water receives, helps avoid too dark lightmapped water" );
+CVAR_DEFINE_AUTO( gl_litwater_scale, "1.5", FCVAR_GLCONFIG, "lightmapped water scale factor" );
 CVAR_DEFINE_AUTO( r_lighting_extended, "1", FCVAR_GLCONFIG, "allow to get lighting from world and bmodels" );
 CVAR_DEFINE_AUTO( r_lighting_ambient, "0.3", FCVAR_GLCONFIG, "map ambient lighting scale" );
 CVAR_DEFINE_AUTO( r_detailtextures, "1", FCVAR_ARCHIVE, "enable detail textures support" );
@@ -1207,6 +1210,9 @@ static void GL_InitCommands( void )
 	gEngfuncs.Cvar_RegisterVariable( &gl_stencilbits );
 	gEngfuncs.Cvar_RegisterVariable( &gl_round_down );
 	gEngfuncs.Cvar_RegisterVariable( &gl_overbright );
+	gEngfuncs.Cvar_RegisterVariable( &gl_litwater_force );
+	gEngfuncs.Cvar_RegisterVariable( &gl_litwater_minlight );
+	gEngfuncs.Cvar_RegisterVariable( &gl_litwater_scale );
 
 	// these cvar not used by engine but some mods requires this
 	gEngfuncs.Cvar_RegisterVariable( &gl_polyoffset );

ref/gl/gl_rmain.c

@@ -1020,13 +1020,21 @@ static void R_CheckGamma( void )
 		ClearBits( gl_overbright.flags, FCVAR_CHANGED );
 	}
 
-	if( gl_overbright.value && ( FBitSet( r_vbo.flags, FCVAR_CHANGED ) || FBitSet( r_vbo_overbrightmode.flags, FCVAR_CHANGED ) ) )
+	if( gl_overbright.value && FBitSet( r_vbo.flags|r_vbo_overbrightmode.flags, FCVAR_CHANGED ))
 	{
 		rebuild = true;
 		ClearBits( r_vbo.flags, FCVAR_CHANGED );
 		ClearBits( r_vbo_overbrightmode.flags, FCVAR_CHANGED );
 	}
 
+	// we only recalculate lightmap on the fly if map hasn't declared support for lightmapped water
+	if( !FBitSet( tr.world->flags, FWORLD_HAS_LITWATER ) && FBitSet( gl_litwater_scale.flags|gl_litwater_minlight.flags, FCVAR_CHANGED ))
+	{
+		rebuild = true;
+		ClearBits( gl_litwater_scale.flags, FCVAR_CHANGED );
+		ClearBits( gl_litwater_minlight.flags, FCVAR_CHANGED );
+	}
+
 	if( rebuild )
 		R_GammaChanged( false );
 }