diff --git a/src/gl/renderer/gl_renderer.h b/src/gl/renderer/gl_renderer.h
index 27263f62c..e3924ad40 100644
--- a/src/gl/renderer/gl_renderer.h
+++ b/src/gl/renderer/gl_renderer.h
@@ -153,6 +153,8 @@ public:
 
 	float mSceneClearColor[3];
 
+	float mGlobVis = 0.0f;
+
 	FGLRenderer(OpenGLFrameBuffer *fb);
 	~FGLRenderer() ;
 
diff --git a/src/gl/renderer/gl_renderstate.cpp b/src/gl/renderer/gl_renderstate.cpp
index 939140640..411b7fb69 100644
--- a/src/gl/renderer/gl_renderstate.cpp
+++ b/src/gl/renderer/gl_renderstate.cpp
@@ -151,6 +151,7 @@ bool FRenderState::ApplyShader()
 	activeShader->muDesaturation.Set(mDesaturation / 255.f);
 	activeShader->muFogEnabled.Set(fogset);
 	activeShader->muPalLightLevels.Set(static_cast<int>(gl_bandedswlight) | (static_cast<int>(gl_fogmode) << 8));
+	activeShader->muGlobVis.Set(GLRenderer->mGlobVis / 32.0f);
 	activeShader->muTextureMode.Set(mTextureMode);
 	activeShader->muCameraPos.Set(mCameraPos.vec);
 	activeShader->muLightParms.Set(mLightParms);
diff --git a/src/gl/scene/gl_scene.cpp b/src/gl/scene/gl_scene.cpp
index 2f1c97ee1..2dc4953cf 100644
--- a/src/gl/scene/gl_scene.cpp
+++ b/src/gl/scene/gl_scene.cpp
@@ -83,7 +83,7 @@ CVAR(Bool, gl_sort_textures, false, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 EXTERN_CVAR (Bool, cl_capfps)
 EXTERN_CVAR (Bool, r_deathcamera)
 EXTERN_CVAR (Float, underwater_fade_scalar)
-
+EXTERN_CVAR (Float, r_visibility)
 
 extern bool NoInterpolateView;
 
@@ -785,6 +785,8 @@ sector_t * GLSceneDrawer::RenderViewpoint (AActor * camera, GL_IRECT * bounds, f
 	R_SetupFrame (r_viewpoint, r_viewwindow, camera);
 	SetViewArea();
 
+	GLRenderer->mGlobVis = R_GetGlobVis(r_viewwindow, r_visibility);
+
 	// We have to scale the pitch to account for the pixel stretching, because the playsim doesn't know about this and treats it as 1:1.
 	double radPitch = r_viewpoint.Angles.Pitch.Normalized180().Radians();
 	double angx = cos(radPitch);
diff --git a/src/gl/shaders/gl_shader.cpp b/src/gl/shaders/gl_shader.cpp
index 758f85435..c944f27c5 100644
--- a/src/gl/shaders/gl_shader.cpp
+++ b/src/gl/shaders/gl_shader.cpp
@@ -230,6 +230,7 @@ bool FShader::Load(const char * name, const char * vert_prog_lump, const char *
 	muDesaturation.Init(hShader, "uDesaturationFactor");
 	muFogEnabled.Init(hShader, "uFogEnabled");
 	muPalLightLevels.Init(hShader, "uPalLightLevels");
+	muGlobVis.Init(hShader, "uGlobVis");
 	muTextureMode.Init(hShader, "uTextureMode");
 	muCameraPos.Init(hShader, "uCameraPos");
 	muLightParms.Init(hShader, "uLightAttr");
diff --git a/src/gl/shaders/gl_shader.h b/src/gl/shaders/gl_shader.h
index e8012aa5d..f41f7467b 100644
--- a/src/gl/shaders/gl_shader.h
+++ b/src/gl/shaders/gl_shader.h
@@ -260,6 +260,7 @@ class FShader
 	FBufferedUniform1f muDesaturation;
 	FBufferedUniform1i muFogEnabled;
 	FBufferedUniform1i muPalLightLevels;
+	FBufferedUniform1f muGlobVis;
 	FBufferedUniform1i muTextureMode;
 	FBufferedUniform4f muCameraPos;
 	FBufferedUniform4f muLightParms;
diff --git a/src/polyrenderer/poly_renderer.cpp b/src/polyrenderer/poly_renderer.cpp
index 2da2dbcf9..fc119e65e 100644
--- a/src/polyrenderer/poly_renderer.cpp
+++ b/src/polyrenderer/poly_renderer.cpp
@@ -40,6 +40,7 @@
 
 EXTERN_CVAR(Bool, r_shadercolormaps)
 EXTERN_CVAR(Int, screenblocks)
+EXTERN_CVAR(Float, r_visibility)
 void InitGLRMapinfoData();
 
 /////////////////////////////////////////////////////////////////////////////
@@ -122,6 +123,7 @@ void PolyRenderer::RenderActorView(AActor *actor, bool dontmaplines)
 	if (APART(R_OldBlend)) NormalLight.Maps = realcolormaps.Maps;
 	else NormalLight.Maps = realcolormaps.Maps + NUMCOLORMAPS * 256 * R_OldBlend;
 
+	Light.SetVisibility(Viewwindow, r_visibility);
 
 	PolyCameraLight::Instance()->SetCamera(Viewpoint, RenderTarget, actor);
 	//Viewport->SetupFreelook();
diff --git a/src/polyrenderer/scene/poly_light.cpp b/src/polyrenderer/scene/poly_light.cpp
index 92c74e469..183f133dc 100644
--- a/src/polyrenderer/scene/poly_light.cpp
+++ b/src/polyrenderer/scene/poly_light.cpp
@@ -27,6 +27,11 @@
 #include "poly_light.h"
 #include "polyrenderer/poly_renderer.h"
 
+void PolyLightVisibility::SetVisibility(FViewWindow &viewwindow, float vis)
+{
+	GlobVis = R_GetGlobVis(viewwindow, vis);
+}
+
 fixed_t PolyLightVisibility::LightLevelToShade(int lightlevel, bool foggy)
 {
 	bool nolightfade = !foggy && ((level.flags3 & LEVEL3_NOLIGHTFADE));
@@ -42,8 +47,3 @@ fixed_t PolyLightVisibility::LightLevelToShade(int lightlevel, bool foggy)
 		return (NUMCOLORMAPS * 2 * FRACUNIT) - ((lightlevel + 12) * (FRACUNIT*NUMCOLORMAPS / 128));
 	}
 }
-
-double PolyLightVisibility::FocalTangent()
-{
-	return PolyRenderer::Instance()->Viewwindow.FocalTangent;
-}
diff --git a/src/polyrenderer/scene/poly_light.h b/src/polyrenderer/scene/poly_light.h
index dcb397cb8..252acf2d6 100644
--- a/src/polyrenderer/scene/poly_light.h
+++ b/src/polyrenderer/scene/poly_light.h
@@ -24,6 +24,8 @@
 
 #include "swrenderer/scene/r_light.h"
 
+struct FViewWindow;
+
 // Keep using the software renderer's camera light class, for now.
 // The DFrameBuffer abstraction relies on this being globally shared
 typedef swrenderer::CameraLight PolyCameraLight;
@@ -31,9 +33,11 @@ typedef swrenderer::CameraLight PolyCameraLight;
 class PolyLightVisibility
 {
 public:
-	double WallGlobVis(bool foggy) const { return (NoLightFade && !foggy) ? 0.0 : WallVisibility / FocalTangent(); }
-	double SpriteGlobVis(bool foggy) const { return (NoLightFade && !foggy) ? 0.0 : WallVisibility / FocalTangent(); }
-	double ParticleGlobVis(bool foggy) const { return (NoLightFade && !foggy) ? 0.0 : WallVisibility * 0.5 / FocalTangent(); }
+	void SetVisibility(FViewWindow &viewwindow, float vis);
+
+	double WallGlobVis(bool foggy) const { return (NoLightFade && !foggy) ? 0.0 : GlobVis; }
+	double SpriteGlobVis(bool foggy) const { return (NoLightFade && !foggy) ? 0.0 : GlobVis; }
+	double ParticleGlobVis(bool foggy) const { return (NoLightFade && !foggy) ? 0.0 : GlobVis * 0.5; }
 
 	// The vis value to pass into the GETPALOOKUP or LIGHTSCALE macros
 	double WallVis(double screenZ, bool foggy) const { return WallGlobVis(foggy) / screenZ; }
@@ -43,9 +47,6 @@ public:
 	static fixed_t LightLevelToShade(int lightlevel, bool foggy);
 
 private:
-	static double FocalTangent();
-
-	// 1706 is the value for walls on 1080p 16:9 displays.
-	double WallVisibility = 1706.0;
+	double GlobVis = 0.0f;
 	bool NoLightFade = false;
 };
diff --git a/src/r_renderer.h b/src/r_renderer.h
index 366663880..01d241bb9 100644
--- a/src/r_renderer.h
+++ b/src/r_renderer.h
@@ -54,9 +54,6 @@ struct FRenderer
 	virtual void CleanLevelData() {}
 	virtual bool RequireGLNodes() { return false; }
 
-	virtual double GetVisibility() { return 8.f; }
-	virtual void SetVisibility(double vis) { }
-
 };
 
 
diff --git a/src/r_utility.cpp b/src/r_utility.cpp
index 9aa8b4cb0..ead7d569b 100644
--- a/src/r_utility.cpp
+++ b/src/r_utility.cpp
@@ -278,6 +278,77 @@ void R_ExecuteSetViewSize (FRenderViewpoint &viewpoint, FViewWindow &viewwindow)
 	viewwindowy = (viewwidth == screen->GetWidth()) ? 0 : (StatusBar->GetTopOfStatusbar() - viewheight) >> 1;
 }
 
+//==========================================================================
+//
+// r_visibility
+//
+// Controls how quickly light ramps across a 1/z range.
+//
+//==========================================================================
+
+double R_ClampVisibility(double vis)
+{
+	// Allow negative visibilities, just for novelty's sake
+	return clamp(vis, -204.7, 204.7);	// (205 and larger do not work in 5:4 aspect ratio)
+}
+
+CUSTOM_CVAR(Float, r_visibility, 8.0f, CVAR_NOINITCALL)
+{
+	if (netgame && self != 8.0f)
+	{
+		Printf("Visibility cannot be changed in net games.\n");
+		self = 8.0f;
+	}
+	else
+	{
+		float clampValue = (float)R_ClampVisibility(self);
+		if (self != clampValue)
+			self = clampValue;
+	}
+}
+
+//==========================================================================
+//
+// R_GetGlobVis
+//
+// Calculates the global visibility constant used by the software renderer
+//
+//==========================================================================
+
+double R_GetGlobVis(const FViewWindow &viewwindow, double vis)
+{
+	vis = R_ClampVisibility(vis);
+
+	double virtwidth = screen->GetWidth();
+	double virtheight = screen->GetHeight();
+
+	if (AspectTallerThanWide(viewwindow.WidescreenRatio))
+	{
+		virtheight = (virtheight * AspectMultiplier(viewwindow.WidescreenRatio)) / 48;
+	}
+	else
+	{
+		virtwidth = (virtwidth * AspectMultiplier(viewwindow.WidescreenRatio)) / 48;
+	}
+
+	double YaspectMul = 320.0 * virtheight / (200.0 * virtwidth);
+	double InvZtoScale = YaspectMul * viewwindow.centerx;
+
+	double wallVisibility = vis;
+
+	// Prevent overflow on walls
+	double maxVisForWall = (InvZtoScale * (screen->GetWidth() * r_Yaspect) / (viewwidth * screen->GetHeight() * viewwindow.FocalTangent));
+	maxVisForWall = 32767.0 / maxVisForWall;
+	if (vis < 0 && vis < -maxVisForWall)
+		wallVisibility = -maxVisForWall;
+	else if (vis > 0 && vis > maxVisForWall)
+		wallVisibility = maxVisForWall;
+
+	wallVisibility = InvZtoScale * screen->GetWidth() * AspectBaseHeight(viewwindow.WidescreenRatio) / (viewwidth * screen->GetHeight() * 3) * (wallVisibility * viewwindow.FocalTangent);
+
+	return wallVisibility / viewwindow.FocalTangent;
+}
+
 //==========================================================================
 //
 // CVAR screenblocks
diff --git a/src/r_utility.h b/src/r_utility.h
index 8a938cc01..07fae0cbb 100644
--- a/src/r_utility.h
+++ b/src/r_utility.h
@@ -122,6 +122,8 @@ void R_ExecuteSetViewSize (FRenderViewpoint &viewpoint, FViewWindow &viewwindow)
 void R_SetViewSize (int blocks);
 void R_SetWindow (FRenderViewpoint &viewpoint, FViewWindow &viewwindow, int windowSize, int fullWidth, int fullHeight, int stHeight, bool renderingToCanvas = false);
 
+double R_GetGlobVis(const FViewWindow &viewwindow, double vis);
+double R_ClampVisibility(double vis);
 
 extern void R_FreePastViewers ();
 extern void R_ClearPastViewer (AActor *actor);
diff --git a/src/sound/musicformats/music_libsndfile.cpp b/src/sound/musicformats/music_libsndfile.cpp
index 85b670a6b..fed79dcf0 100644
--- a/src/sound/musicformats/music_libsndfile.cpp
+++ b/src/sound/musicformats/music_libsndfile.cpp
@@ -339,18 +339,12 @@ bool SndFileSong::Read(SoundStream *stream, void *vbuff, int ilen, void *userdat
 		if (currentpos + framestoread > song->Loop_End)
 		{
 			size_t endblock = (song->Loop_End - currentpos) * song->Channels * 2;
-			size_t endlen = song->Decoder->read(buff, 0 == endblock ? len : endblock);
-			if (endlen != 0)
-			{
-				buff = buff + endlen;
-				len -= endlen;
-				song->Decoder->seek(song->Loop_Start, false, true);
-			}
-			else
-			{
-				song->CritSec.Leave();
-				return false;
-			}
+			size_t endlen = song->Decoder->read(buff, endblock);
+
+			// Even if zero bytes was read give it a chance to start from the beginning
+			buff = buff + endlen;
+			len -= endlen;
+			song->Decoder->seek(song->Loop_Start, false, true);
 		}
 		while (len > 0)
 		{
diff --git a/src/swrenderer/r_swrenderer.cpp b/src/swrenderer/r_swrenderer.cpp
index de1172740..93cfcb78f 100644
--- a/src/swrenderer/r_swrenderer.cpp
+++ b/src/swrenderer/r_swrenderer.cpp
@@ -378,14 +378,3 @@ void FSoftwareRenderer::PreprocessLevel()
 void FSoftwareRenderer::CleanLevelData()
 {
 }
-
-double FSoftwareRenderer::GetVisibility()
-{
-	return mScene.MainThread()->Light->GetVisibility();
-}
-
-void FSoftwareRenderer::SetVisibility(double vis)
-{
-	mScene.MainThread()->Light->SetVisibility(mScene.MainThread()->Viewport.get(), vis);
-}
-
diff --git a/src/swrenderer/r_swrenderer.h b/src/swrenderer/r_swrenderer.h
index eeb6fd36c..91b4dcdfb 100644
--- a/src/swrenderer/r_swrenderer.h
+++ b/src/swrenderer/r_swrenderer.h
@@ -35,9 +35,6 @@ struct FSoftwareRenderer : public FRenderer
 	void PreprocessLevel() override;
 	void CleanLevelData() override;
 
-	double GetVisibility() override;
-	void SetVisibility(double vis) override;
-
 private:
 	void PrecacheTexture(FTexture *tex, int cache);
 
diff --git a/src/swrenderer/scene/r_light.cpp b/src/swrenderer/scene/r_light.cpp
index 685ce369c..022f2745f 100644
--- a/src/swrenderer/scene/r_light.cpp
+++ b/src/swrenderer/scene/r_light.cpp
@@ -104,8 +104,7 @@ namespace swrenderer
 	// Changes how rapidly things get dark with distance
 	void LightVisibility::SetVisibility(RenderViewport *viewport, double vis)
 	{
-		// Allow negative visibilities, just for novelty's sake
-		vis = clamp(vis, -204.7, 204.7);	// (205 and larger do not work in 5:4 aspect ratio)
+		vis = R_ClampVisibility(vis);
 
 		CurrentVisibility = vis;
 
@@ -167,25 +166,6 @@ namespace swrenderer
 		}
 	}
 
-	// Controls how quickly light ramps across a 1/z range. Set this, and it
-	// sets all the r_*Visibility variables (except r_SkyVisibilily, which is
-	// currently unused).
-	CCMD(r_visibility)
-	{
-		if (argv.argc() < 2)
-		{
-			Printf("Visibility is %g\n", Renderer->GetVisibility());
-		}
-		else if (!netgame)
-		{
-			Renderer->SetVisibility(atof(argv[1]));
-		}
-		else
-		{
-			Printf("Visibility cannot be changed in net games.\n");
-		}
-	}
-
 	/////////////////////////////////////////////////////////////////////////
 
 	void ColormapLight::SetColormap(double visibility, int shade, FDynamicColormap *basecolormap, bool fullbright, bool invertColormap, bool fadeToBlack)
diff --git a/src/swrenderer/viewport/r_viewport.cpp b/src/swrenderer/viewport/r_viewport.cpp
index 9cfac4373..783fc8f0d 100644
--- a/src/swrenderer/viewport/r_viewport.cpp
+++ b/src/swrenderer/viewport/r_viewport.cpp
@@ -46,6 +46,8 @@
 
 CVAR(String, r_viewsize, "", CVAR_NOSET)
 
+EXTERN_CVAR(Float, r_visibility);
+
 namespace swrenderer
 {
 	RenderViewport::RenderViewport()
@@ -109,7 +111,7 @@ namespace swrenderer
 		InitTextureMapping();
 
 		// Reset r_*Visibility vars
-		thread->Light->SetVisibility(this, thread->Light->GetVisibility());
+		thread->Light->SetVisibility(this, r_visibility);
 
 		SetupBuffer();
 	}
diff --git a/src/win32/hardware.cpp b/src/win32/hardware.cpp
index 0fb64c008..2c5987726 100644
--- a/src/win32/hardware.cpp
+++ b/src/win32/hardware.cpp
@@ -56,6 +56,7 @@ EXTERN_CVAR (Bool, vid_forceddraw)
 
 CVAR(Int, win_x, -1, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
 CVAR(Int, win_y, -1, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
+CVAR(Bool, win_maximized, false, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
 
 extern HWND Window;
 
@@ -382,6 +383,8 @@ void I_SaveWindowedPos ()
 			win_x = wrect.left;
 			win_y = wrect.top;
 		}
+
+		win_maximized = IsZoomed(Window) == TRUE;
 	}
 }
 
@@ -409,6 +412,9 @@ void I_RestoreWindowedPos ()
 		KeepWindowOnScreen (winx, winy, winw, winh, scrwidth, scrheight);
 	}
 	MoveWindow (Window, winx, winy, winw, winh, TRUE);
+
+	if (win_maximized && !Args->CheckParm("-0"))
+		ShowWindow(Window, SW_MAXIMIZE);
 }
 
 extern int NewWidth, NewHeight, NewBits, DisplayBits;
diff --git a/wadsrc/static/shaders/glsl/main.fp b/wadsrc/static/shaders/glsl/main.fp
index 0c27e8cf0..d3fd31882 100644
--- a/wadsrc/static/shaders/glsl/main.fp
+++ b/wadsrc/static/shaders/glsl/main.fp
@@ -103,12 +103,6 @@ vec4 getTexel(vec2 st)
 //===========================================================================
 float R_DoomLightingEquation(float light)
 {
-	// globVis = WallVisibility / r_viewwindow.FocalTangent / 32.0
-	//
-	// WallVisibility is calculated in LightVisibility::SetVisibility
-	// 1706 is the default value for WallVisibility on 1080p 16:9 displays.
-	float globVis = 1706.0 / 1.3333333333333333 / 32.0;
-
 	// L is the integer light level used in the game
 	float L = light * 255.0;
 
@@ -124,7 +118,7 @@ float R_DoomLightingEquation(float light)
 	}
 
 	// The zdoom light equation
-	float vis = min(globVis / z, 24.0 / 32.0);
+	float vis = min(uGlobVis / z, 24.0 / 32.0);
 	float shade = 2.0 - (L + 12.0) / 128.0;
 	float lightscale;
 	if ((uPalLightLevels & 0xff) != 0)
diff --git a/wadsrc/static/shaders/glsl/shaderdefs.i b/wadsrc/static/shaders/glsl/shaderdefs.i
index c109c8524..c8fcf7b6b 100644
--- a/wadsrc/static/shaders/glsl/shaderdefs.i
+++ b/wadsrc/static/shaders/glsl/shaderdefs.i
@@ -43,6 +43,7 @@ uniform vec4 uLightAttr;
 #define uLightDist uLightAttr.r
 uniform int uFogEnabled;
 uniform int uPalLightLevels;
+uniform float uGlobVis; // uGlobVis = R_GetGlobVis(r_visibility) / 32.0
 
 // dynamic lights
 uniform int uLightIndex;