- cleaned up the gamma correction code.

This had accumulated quite a bit of cruft by now and parts of it should be in non OpenGL code.

src/gl/system/gl_framebuffer.cpp

@@ -42,8 +42,6 @@
 #include "gl_debug.h"
 #include "r_videoscale.h"
 
-EXTERN_CVAR (Float, vid_brightness)
-EXTERN_CVAR (Float, vid_contrast)
 EXTERN_CVAR (Bool, vid_vsync)
 
 CVAR(Bool, gl_aalines, false, CVAR_ARCHIVE)
@@ -56,7 +54,7 @@ void gl_PrintStartupLog();
 CUSTOM_CVAR(Int, vid_hwgamma, 2, CVAR_ARCHIVE | CVAR_GLOBALCONFIG | CVAR_NOINITCALL)
 {
 	if (self < 0 || self > 2) self = 2;
-	if (GLRenderer != NULL && GLRenderer->framebuffer != NULL) GLRenderer->framebuffer->DoSetGamma();
+	if (screen != nullptr) screen->SetGamma();
 }
 
 //==========================================================================
@@ -85,7 +83,7 @@ OpenGLFrameBuffer::OpenGLFrameBuffer(void *hMonitor, int width, int height, int
 	InitializeState();
 	mDebug = std::make_shared<FGLDebug>();
 	mDebug->Update();
-	DoSetGamma();
+	SetGamma();
 	hwcaps = gl.flags;
 	if (gl.legacyMode) hwcaps |= RFL_NO_SHADERS;
 }
@@ -321,7 +319,7 @@ void OpenGLFrameBuffer::SetVSync(bool vsync)
 //
 //===========================================================================
 
-void OpenGLFrameBuffer::DoSetGamma()
+void OpenGLFrameBuffer::SetGamma()
 {
 	bool useHWGamma = m_supportsGamma && ((vid_hwgamma == 0) || (vid_hwgamma == 2 && IsFullscreen()));
 	if (useHWGamma)
@@ -329,21 +327,7 @@ void OpenGLFrameBuffer::DoSetGamma()
 		uint16_t gammaTable[768];
 
 		// This formula is taken from Doomsday
-		float gamma = clamp<float>(Gamma, 0.1f, 4.f);
+		BuildGammaTable(gammaTable);
-		float contrast = clamp<float>(vid_contrast, 0.1f, 3.f);
-		float bright = clamp<float>(vid_brightness, -0.8f, 0.8f);
-
-		double invgamma = 1 / gamma;
-		double norm = pow(255., invgamma - 1);
-
-		for (int i = 0; i < 256; i++)
-		{
-			double val = i * contrast - (contrast - 1) * 127;
-			val += bright * 128;
-			if(gamma != 1) val = pow(val, invgamma) / norm;
-
-			gammaTable[i] = gammaTable[i + 256] = gammaTable[i + 512] = (uint16_t)clamp<double>(val*256, 0, 0xffff);
-		}
 		SetGammaTable(gammaTable);
 
 		HWGammaActive = true;
@@ -355,24 +339,6 @@ void OpenGLFrameBuffer::DoSetGamma()
 	}
 }
 
-bool OpenGLFrameBuffer::SetGamma(float gamma)
-{
-	DoSetGamma();
-	return true;
-}
-
-bool OpenGLFrameBuffer::SetBrightness(float bright)
-{
-	DoSetGamma();
-	return true;
-}
-
-bool OpenGLFrameBuffer::SetContrast(float contrast)
-{
-	DoSetGamma();
-	return true;
-}
-
 //===========================================================================
 //
 //

src/gl/system/gl_framebuffer.h

@@ -23,10 +23,7 @@ public:
 	void Update();
 
 	// Color correction
-	bool SetGamma (float gamma);
+	void SetGamma();
-	bool SetBrightness(float bright);
-	bool SetContrast(float contrast);
-	void DoSetGamma();
 
 	void CleanForRestart() override;
 	void UpdatePalette() override;

src/hwrenderer/utility/hw_cvars.cpp

@@ -57,7 +57,7 @@ CUSTOM_CVAR (Float, vid_brightness, 0.f, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 {
 	if (screen != NULL)
 	{
-		screen->SetGamma(Gamma); //Brightness (self);
+		screen->SetGamma();
 	}
 }
 
@@ -65,7 +65,7 @@ CUSTOM_CVAR (Float, vid_contrast, 1.f, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 {
 	if (screen != NULL)
 	{
-		screen->SetGamma(Gamma); //SetContrast (self);
+		screen->SetGamma();
 	}
 }
 
@@ -73,7 +73,7 @@ CUSTOM_CVAR (Float, vid_saturation, 1.f, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 {
 	if (screen != NULL)
 	{
-		screen->SetGamma(Gamma);
+		screen->SetGamma();
 	}
 }
 

src/posix/cocoa/i_video.mm

@@ -267,7 +267,7 @@ CUSTOM_CVAR(Float, rgamma, 1.0f, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
 {
 	if (NULL != screen)
 	{
-		screen->SetGamma(Gamma);
+		screen->SetGamma();
 	}
 }
 
@@ -275,7 +275,7 @@ CUSTOM_CVAR(Float, ggamma, 1.0f, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
 {
 	if (NULL != screen)
 	{
-		screen->SetGamma(Gamma);
+		screen->SetGamma();
 	}
 }
 
@@ -283,7 +283,7 @@ CUSTOM_CVAR(Float, bgamma, 1.0f, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
 {
 	if (NULL != screen)
 	{
-		screen->SetGamma(Gamma);
+		screen->SetGamma();
 	}
 }
 

src/v_palette.cpp

@@ -73,7 +73,7 @@ CUSTOM_CVAR (Float, Gamma, 1.f, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 
 	if (screen != NULL)
 	{
-		screen->SetGamma (self);
+		screen->SetGamma ();
 	}
 }
 

src/v_video.cpp

@@ -73,6 +73,8 @@
 #include "i_time.h"
 
 EXTERN_CVAR(Bool, cl_capfps)
+EXTERN_CVAR(Float, vid_brightness)
+EXTERN_CVAR(Float, vid_contrast)
 
 CUSTOM_CVAR(Int, vid_maxfps, 200, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
 {
@@ -129,7 +131,6 @@ public:
 	PalEntry *GetPalette() { DBGBREAK; return NULL; }
 	void GetFlashedPalette(PalEntry palette[256]) { DBGBREAK; }
 	void UpdatePalette() { DBGBREAK; }
-	bool SetGamma(float gamma) { Gamma = gamma; return true; }
 	bool SetFlash(PalEntry rgb, int amount) { DBGBREAK; return false; }
 	void GetFlash(PalEntry &rgb, int &amount) { DBGBREAK; }
 	bool IsFullscreen() { DBGBREAK; return 0; }
@@ -928,6 +929,31 @@ void DFrameBuffer::GameRestart()
 {
 }
 
+//==========================================================================
+//
+//
+//
+//==========================================================================
+
+void DFrameBuffer::BuildGammaTable(uint16_t *gammaTable)
+{
+	float gamma = clamp<float>(Gamma, 0.1f, 4.f);
+	float contrast = clamp<float>(vid_contrast, 0.1f, 3.f);
+	float bright = clamp<float>(vid_brightness, -0.8f, 0.8f);
+
+	double invgamma = 1 / gamma;
+	double norm = pow(255., invgamma - 1);
+
+	for (int i = 0; i < 256; i++)
+	{
+		double val = i * contrast - (contrast - 1) * 127;
+		val += bright * 128;
+		if (gamma != 1) val = pow(val, invgamma) / norm;
+
+		gammaTable[i] = gammaTable[i + 256] = gammaTable[i + 512] = (uint16_t)clamp<double>(val * 256, 0, 0xffff);
+	}
+}
+
 //==========================================================================
 //
 // DFrameBuffer :: GetCaps
@@ -986,7 +1012,7 @@ bool V_DoModeSetup (int width, int height, int bits)
 	}
 
 	screen = buff;
-	screen->SetGamma (Gamma);
+	screen->SetGamma ();
 
 	DisplayBits = bits;
 	V_UpdateModeSize(screen->GetWidth(), screen->GetHeight());
@@ -1264,7 +1290,7 @@ void V_Init2()
 	else
 		Printf ("Resolution: %d x %d\n", SCREENWIDTH, SCREENHEIGHT);
 
-	screen->SetGamma (gamma);
+	screen->SetGamma ();
 	FBaseCVar::ResetColors ();
 	C_NewModeAdjust();
 	M_InitVideoModesMenu();

src/v_video.h

@@ -318,6 +318,7 @@ protected:
 	template<class T>
 	bool ParseDrawTextureTags(FTexture *img, double x, double y, uint32_t tag, T& tags, DrawParms *parms, bool fortext) const;
 	void DrawTextCommon(FFont *font, int normalcolor, double x, double y, const char *string, DrawParms &parms);
+	void BuildGammaTable(uint16_t *gt);
 
 	F2DDrawer m2DDrawer;
 	int Width = 0;
@@ -351,7 +352,7 @@ public:
 	// Sets the gamma level. Returns false if the hardware does not support
 	// gamma changing. (Always true for now, since palettes can always be
 	// gamma adjusted.)
-	virtual bool SetGamma (float gamma) = 0;
+	virtual void SetGamma() {}
 
 	// Sets a color flash. RGB is the color, and amount is 0-256, with 256
 	// being all flash and 0 being no flash. Returns false if the hardware