engine: client: add new gamma implementation

* immediately expose it in RefAPI. Bump RefAPI to version 7.
* remove VID_StartupGamma, it's not used anymore
* remove stub lightgamma and direct cvars
* add a temporary check for v_direct and v_lightgamma default values

engine/client/cl_main.c

@@ -2922,10 +2922,6 @@ void CL_InitLocal( void )
 	Cvar_RegisterVariable( &cl_maxframetime );
 	Cvar_RegisterVariable( &cl_fixmodelinterpolationartifacts );
 
-	// these two added to shut up CS 1.5 about 'unknown' commands
-	Cvar_Get( "lightgamma", "1", FCVAR_ARCHIVE, "ambient lighting level (legacy, unused)" );
-	Cvar_Get( "direct", "1", FCVAR_ARCHIVE, "direct lighting level (legacy, unused)" );
-
 	// server commands
 	Cmd_AddCommand ("noclip", NULL, "enable or disable no clipping mode" );
 	Cmd_AddCommand ("notarget", NULL, "notarget mode (monsters do not see you)" );

engine/client/cl_scrn.c

@@ -292,6 +292,8 @@ void SCR_MakeScreenShot( void )
 		viewsize = cls.envshot_viewsize;
 	else viewsize = cl_envshot_size.value;
 
+	V_CheckGamma();
+
 	switch( cls.scrshot_action )
 	{
 	case scrshot_normal:

engine/client/cl_view.c

@@ -347,6 +347,8 @@ qboolean V_PreRender( void )
 		return false;
 	}
 
+	V_CheckGamma();
+
 	ref.dllFuncs.R_BeginFrame( !cl.paused && ( cls.state == ca_active ));
 
 	GL_UpdateSwapInterval( );

engine/client/gamma.c

@@ -0,0 +1,214 @@
+/*
+gamma.c - gamma routines
+Copyright (C) 2011 Uncle Mike
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+*/
+
+#include "common.h"
+#include "client.h"
+#include "xash3d_mathlib.h"
+#include "enginefeatures.h"
+
+//-----------------------------------------------------------------------------
+// Gamma conversion support
+//-----------------------------------------------------------------------------
+static byte	texgammatable[256];
+static uint	lightgammatable[1024];
+static uint	lineargammatable[1024];
+static uint	screengammatable[1024];
+static CVAR_DEFINE( v_direct, "direct", "0.9", 0, "direct studio lighting" );
+static CVAR_DEFINE( v_texgamma, "texgamma", "2.0", 0, "texgamma amount" );
+static CVAR_DEFINE( v_lightgamma, "lightgamma", "2.5", 0, "lightgamma amount" );
+static CVAR_DEFINE( v_brightness, "brightness", "0.0", FCVAR_ARCHIVE, "brightness factor" );
+static CVAR_DEFINE( v_gamma, "gamma", "2.5", FCVAR_ARCHIVE, "gamma amount" );
+
+static void BuildGammaTable( const float gamma, const float brightness, const float texgamma, const float lightgamma )
+{
+	float g1, g2, g3;
+	int i;
+
+	if( gamma != 0.0 )
+		g1 = 1.0 / gamma;
+	else g1 = 0.4;
+
+	g2 = g1 * texgamma;
+
+	if( brightness <= 0.0 )
+		g3 = 0.125;
+	else if( brightness <= 1.0 )
+		g3 = 0.125 - brightness * brightness * 0.075;
+	else
+		g3 = 0.05;
+
+	for( i = 0; i < 256; i++ )
+	{
+		double d = pow( i / 255.0, (double)g2 );
+		int inf = d * 255.0;
+		texgammatable[i] = bound( 0, inf, 255 );
+	}
+
+	for( i = 0; i < 1024; i++ )
+	{
+		double d;
+		float f = pow( i / 1023.0, (double)lightgamma );
+		int inf;
+
+		if( brightness > 1.0 )
+			f *= brightness;
+
+		if( f <= g3 )
+			f = ( f / g3 ) * 0.125;
+		else
+			f = (( f - g3 ) / ( 1.0 - g3 )) * 0.875 + 0.125;
+
+		d = pow( (double)f, (double)g1 ); // do not remove the cast, or tests fail
+		inf = d * 1023.0;
+		lightgammatable[i] = bound( 0, inf, 1023 );
+
+		// do these calculations in the same loop...
+		lineargammatable[i] = pow( i / 1023.0, (double)gamma ) * 1023.0;
+		screengammatable[i] = pow( i / 1023.0, 1.0 / gamma ) * 1023.0;
+	}
+}
+
+static void V_ValidateGammaCvars( void )
+{
+	if( Host_IsLocalGame( ))
+		return;
+
+	if( v_gamma.value < 1.8f )
+		Cvar_DirectSet( &v_gamma, "1.8" );
+	else if( v_gamma.value > 3.0f )
+		Cvar_DirectSet( &v_gamma, "3" );
+
+	if( v_texgamma.value < 1.8f )
+		Cvar_DirectSet( &v_texgamma, "1.8" );
+	else if( v_texgamma.value > 3.0f )
+		Cvar_DirectSet( &v_texgamma, "3" );
+
+	if( v_lightgamma.value < 1.8f )
+		Cvar_DirectSet( &v_lightgamma, "1.8" );
+	else if( v_lightgamma.value > 3.0f )
+		Cvar_DirectSet( &v_lightgamma, "3" );
+
+	if( v_brightness.value < 0.0f )
+		Cvar_DirectSet( &v_brightness, "0" );
+	else if( v_brightness.value > 2.0f )
+		Cvar_DirectSet( &v_brightness, "2" );
+}
+
+void V_CheckGamma( void )
+{
+	static qboolean dirty = false;
+	qboolean notify_refdll = false;
+
+	// because these cvars were defined as archive
+	// but wasn't doing anything useful
+	// reset them into default values
+	// this might be removed after a while
+	if( v_direct.value == 1.0f || v_lightgamma.value == 1.0f )
+	{
+		Cvar_DirectSet( &v_direct, "0.9" );
+		Cvar_DirectSet( &v_lightgamma, "2.5" );
+	}
+
+	if( cls.scrshot_action == scrshot_envshot || cls.scrshot_action == scrshot_skyshot )
+	{
+		dirty = true; // force recalculate next normal frame
+		BuildGammaTable( 1.8f, 0.0f, 2.0f, 2.5f );
+		if( ref.initialized )
+			ref.dllFuncs.R_GammaChanged( true );
+		return;
+	}
+
+	if( dirty || FBitSet( v_texgamma.flags|v_lightgamma.flags|v_brightness.flags|v_gamma.flags, FCVAR_CHANGED ))
+	{
+		V_ValidateGammaCvars();
+
+		dirty = false;
+		BuildGammaTable( v_gamma.value, v_brightness.value, v_texgamma.value, v_lightgamma.value );
+
+		// force refdll to recalculate lightmaps
+		notify_refdll = true;
+
+		// unfortunately, recalculating textures isn't possible yet
+		ClearBits( v_texgamma.flags, FCVAR_CHANGED );
+		ClearBits( v_lightgamma.flags, FCVAR_CHANGED );
+		ClearBits( v_brightness.flags, FCVAR_CHANGED );
+		ClearBits( v_gamma.flags, FCVAR_CHANGED );
+	}
+
+	if( notify_refdll && ref.initialized )
+		ref.dllFuncs.R_GammaChanged( false );
+}
+
+void V_Init( void )
+{
+	Cvar_RegisterVariable( &v_texgamma );
+	Cvar_RegisterVariable( &v_lightgamma );
+	Cvar_RegisterVariable( &v_brightness );
+	Cvar_RegisterVariable( &v_gamma );
+	Cvar_RegisterVariable( &v_direct );
+
+	// force gamma init
+	SetBits( v_gamma.flags, FCVAR_CHANGED );
+	V_CheckGamma();
+}
+
+byte TextureToGamma( byte b )
+{
+	if( FBitSet( host.features, ENGINE_LINEAR_GAMMA_SPACE ))
+		return b;
+
+	return texgammatable[b];
+}
+
+byte LightToTexGamma( byte b )
+{
+	if( FBitSet( host.features, ENGINE_LINEAR_GAMMA_SPACE ))
+		return b;
+
+	// 255 << 2 is 1020, impossible to overflow
+	return lightgammatable[b << 2] >> 2;
+}
+
+uint LightToTexGammaEx( uint b )
+{
+	if( FBitSet( host.features, ENGINE_LINEAR_GAMMA_SPACE ))
+		return b;
+
+	if( unlikely( b > ARRAYSIZE( lightgammatable )))
+		return 0;
+
+	return lightgammatable[b];
+}
+
+uint ScreenGammaTable( uint b )
+{
+	if( FBitSet( host.features, ENGINE_LINEAR_GAMMA_SPACE ))
+		return b;
+
+	if( unlikely( b > ARRAYSIZE( screengammatable )))
+		return 0;
+
+	return screengammatable[b];
+}
+
+uint LinearGammaTable( uint b )
+{
+	if( FBitSet( host.features, ENGINE_LINEAR_GAMMA_SPACE ))
+		return b;
+
+	if( unlikely( b > ARRAYSIZE( lineargammatable )))
+		return 0;
+	return lineargammatable[b];
+}

engine/client/ref_common.c

@@ -178,25 +178,6 @@ static screenfade_t *pfnRefGetScreenFade( void )
 	return &clgame.fade;
 }
 
-/*
-===============
-R_DoResetGamma
-gamma will be reset for
-some type of screenshots
-===============
-*/
-static qboolean R_DoResetGamma( void )
-{
-	switch( cls.scrshot_action )
-	{
-	case scrshot_envshot:
-	case scrshot_skyshot:
-		return true;
-	default:
-		return false;
-	}
-}
-
 static qboolean R_Init_Video_( const int type )
 {
 	host.apply_opengl_config = true;
@@ -306,9 +287,11 @@ static ref_api_t gEngfuncs =
 	SW_LockBuffer,
 	SW_UnlockBuffer,
 
-	BuildGammaTable,
 	LightToTexGamma,
-	R_DoResetGamma,
+	LightToTexGammaEx,
+	TextureToGamma,
+	ScreenGammaTable,
+	LinearGammaTable,
 
 	CL_GetLightStyle,
 	CL_GetDynamicLight,

engine/client/vid_common.c

@@ -22,8 +22,6 @@ GNU General Public License for more details.
 
 static CVAR_DEFINE( window_width, "width", "0", FCVAR_RENDERINFO|FCVAR_VIDRESTART, "screen width" );
 static CVAR_DEFINE( window_height, "height", "0", FCVAR_RENDERINFO|FCVAR_VIDRESTART, "screen height" );
-static CVAR_DEFINE( vid_brightness, "brightness", "0.0", FCVAR_ARCHIVE, "brightness factor" );
-static CVAR_DEFINE( vid_gamma, "gamma", "2.5", FCVAR_ARCHIVE, "gamma amount" );
 static CVAR_DEFINE_AUTO( vid_mode, "0", FCVAR_RENDERINFO, "current video mode index (used only for storage)" );
 static CVAR_DEFINE_AUTO( vid_rotate, "0", FCVAR_RENDERINFO|FCVAR_VIDRESTART, "screen rotation (0-3)" );
 static CVAR_DEFINE_AUTO( vid_scale, "1.0", FCVAR_RENDERINFO|FCVAR_VIDRESTART, "pixel scale" );
@@ -36,19 +34,6 @@ CVAR_DEFINE( window_ypos, "_window_ypos", "-1", FCVAR_RENDERINFO, "window positi
 
 glwstate_t	glw_state;
 
-/*
-=================
-VID_StartupGamma
-=================
-*/
-void VID_StartupGamma( void )
-{
-	BuildGammaTable( vid_gamma.value, vid_brightness.value );
-	Con_Reportf( "VID_StartupGamma: gamma %g brightness %g\n", vid_gamma.value, vid_brightness.value );
-	ClearBits( vid_brightness.flags, FCVAR_CHANGED );
-	ClearBits( vid_gamma.flags, FCVAR_CHANGED );
-}
-
 /*
 =================
 VID_InitDefaultResolution
@@ -224,8 +209,6 @@ void VID_Init( void )
 	Cvar_RegisterVariable( &vid_scale );
 	Cvar_RegisterVariable( &vid_fullscreen );
 	Cvar_RegisterVariable( &vid_maximized );
-	Cvar_RegisterVariable( &vid_brightness );
-	Cvar_RegisterVariable( &vid_gamma );
 	Cvar_RegisterVariable( &window_xpos );
 	Cvar_RegisterVariable( &window_ypos );
 
@@ -233,5 +216,6 @@ void VID_Init( void )
 	// but supported mode list is filled by backends, so numbers are not portable any more
 	Cmd_AddRestrictedCommand( "vid_setmode", VID_Mode_f, "display video mode" );
 
+	V_Init(); // init gamma
 	R_Init(); // init renderer
 }

engine/client/vid_common.h

@@ -46,6 +46,5 @@ void R_SaveVideoMode( int w, int h, int render_w, int render_h, qboolean maximiz
 void VID_SetDisplayTransform( int *render_w, int *render_h );
 void VID_CheckChanges( void );
 const char *VID_GetModeString( int vid_mode );
-void VID_StartupGamma( void );
 
 #endif // VID_COMMON

engine/common/common.h

@@ -812,8 +812,13 @@ void S_StopBackgroundTrack( void );
 void S_StopAllSounds( qboolean ambient );
 
 // gamma routines
-void BuildGammaTable( float gamma, float brightness );
 byte LightToTexGamma( byte b );
+byte TextureToGamma( byte );
+uint LightToTexGammaEx( uint );
+uint ScreenGammaTable( uint );
+uint LinearGammaTable( uint );
+void V_Init( void );
+void V_CheckGamma( void );
 
 //
 // identification.c

engine/common/gamma.c

@@ -1,78 +0,0 @@
-/*
-gamma.c - gamma routines
-Copyright (C) 2011 Uncle Mike
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 3 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-*/
-
-#include "common.h"
-#include "xash3d_mathlib.h"
-#include "enginefeatures.h"
-
-//-----------------------------------------------------------------------------
-// Gamma conversion support
-//-----------------------------------------------------------------------------
-static byte	lightgammatable[256];
-static int	lineargammatable[1024];
-static int	screengammatable[1024];
-
-void BuildGammaTable( float lightgamma, float brightness )
-{
-	int	i, inf;
-	float	f, g, g1, g3;
-
-	lightgamma = bound( 1.8f, lightgamma, 3.0f );
-	brightness = bound( 0.0f, brightness, 10.0f );
-
-	if( brightness <= 0.0f )
-		g3 = 0.125f;
-	else if( brightness > 1.0f )
-		g3 = 0.05f;
-	else g3 = 0.125f - (brightness * brightness) * 0.075f;
-
-	g = 1.0f / lightgamma;
-	g1 = GAMMA * g;
-
-	for( i = 0; i < 256; i++ )
-	{
-		f = pow( i / 255.f, GAMMA );
-
-		// scale up
-		if( brightness > 1.0f )
-			f = f * brightness;
-
-		// shift up
-		if( f <= g3 ) f = (f / g3) * 0.125f;
-		else f = 0.125f + ((f - g3) / (1.0f - g3)) * 0.875f;
-
-		// convert linear space to desired gamma space
-		inf = (int)( 255.0f * pow( f, g ));
-
-		lightgammatable[i] = bound( 0, inf, 255 );
-	}
-
-	for( i = 0; i < 1024; i++ )
-	{
-		// convert from screen gamma space to linear space
-		lineargammatable[i] = 1023 * pow( i / 1023.0f, g1 );
-
-		// convert from linear gamma space to screen space
-		screengammatable[i] = 1023 * pow( i / 1023.0f, 1.0f / g1 );
-	}
-}
-
-byte LightToTexGamma( byte b )
-{
-	if( FBitSet( host.features, ENGINE_LINEAR_GAMMA_SPACE ))
-		return b;
-	else
-		return lightgammatable[b];
-}

engine/platform/dos/vid_dos.c

@@ -48,8 +48,6 @@ qboolean  R_Init_Video( const int type )
 {
 	qboolean retval;
 
-	VID_StartupGamma();
-
 	if( type != REF_SOFTWARE )
 		return false; /// glide???
 

engine/platform/linux/vid_fbdev.c

@@ -51,8 +51,6 @@ qboolean  R_Init_Video( const int type )
 	string fbdev = DEFAULT_FBDEV;
 	fb.fd = -1;
 
-	VID_StartupGamma();
-
 	if( type != REF_SOFTWARE )
 		return false;
 

engine/platform/sdl/vid_sdl.c

@@ -843,13 +843,10 @@ qboolean VID_CreateWindow( int width, int height, window_mode_t window_mode )
 					return false;
 				GL_SetupAttributes(); // re-choose attributes
 			}
-
-			VID_StartupGamma();
 		}
 
 		if( !GL_UpdateContext( ))
-		return false;
-
+			return false;
 	}
 
 #else // SDL_VERSION_ATLEAST( 2, 0, 0 )

engine/ref_api.h

@@ -42,7 +42,8 @@ GNU General Public License for more details.
 // 6. Removed timing from ref_globals_t.
 //    Renderers are supposed to migrate to ref_client_t/ref_host_t using PARM_GET_CLIENT_PTR and PARM_GET_HOST_PTR
 //    Removed functions to get internal engine structions. Use PARM_GET_*_PTR instead.
-#define REF_API_VERSION 6
+// 7. Gamma fixes.
+#define REF_API_VERSION 7
 
 
 #define TF_SKY		(TF_SKYSIDE|TF_NOMIPMAP)
@@ -404,9 +405,11 @@ typedef struct ref_api_s
 	void (*SW_UnlockBuffer)( void );
 
 	// gamma
-	void (*BuildGammaTable)( float lightgamma, float brightness );
-	byte		(*LightToTexGamma)( byte color );	// software gamma support
-	qboolean	(*R_DoResetGamma)( void );
+	byte (*LightToTexGamma)( byte );	// software gamma support
+	uint (*LightToTexGammaEx)( uint );	// software gamma support
+	byte (*TextureToGamma)( byte );
+	uint (*ScreenGammaTable)( uint );
+	uint (*LinearGammaTable)( uint );
 
 	// renderapi
 	lightstyle_t*	(*GetLightStyle)( int number );
@@ -652,6 +655,8 @@ typedef int (*REFAPI)( int version, ref_interface_t *pFunctionTable, ref_api_t*
 #define ENGINE_SHARED_CVAR_LIST( f ) \
 	ENGINE_SHARED_CVAR_NAME( f, vid_gamma, gamma ) \
 	ENGINE_SHARED_CVAR_NAME( f, vid_brightness, brightness ) \
+	ENGINE_SHARED_CVAR_NAME( f, v_lightgamma, lightgamma ) \
+	ENGINE_SHARED_CVAR_NAME( f, v_direct, direct ) \
 	ENGINE_SHARED_CVAR( f, r_showtextures ) \
 	ENGINE_SHARED_CVAR( f, r_speeds ) \
 	ENGINE_SHARED_CVAR( f, r_fullbright ) \