diff --git a/src/gl/dynlights/gl_dynlight1.cpp b/src/gl/dynlights/gl_dynlight1.cpp
index 5c5e26f03..d20f5c01b 100644
--- a/src/gl/dynlights/gl_dynlight1.cpp
+++ b/src/gl/dynlights/gl_dynlight1.cpp
@@ -60,11 +60,6 @@ CVAR (Bool, gl_lights_checkside, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
 CVAR (Bool, gl_light_sprites, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
 CVAR (Bool, gl_light_particles, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
 
-CUSTOM_CVAR(Int, gl_light_math, 0, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
-{
-	if (self < 0 || self > 2) self = 0;
-}
-
 //==========================================================================
 //
 // Sets up the parameters to render one dynamic light onto one plane
@@ -113,25 +108,10 @@ bool gl_GetLight(int group, Plane & p, ADynamicLight * light, bool checkside, FD
 		i = 1;
 	}
 
-	float worldPos[4] = { (float)pos.X, (float)pos.Z, (float)pos.Y, 1.0f };
-	float eyePos[4];
-	gl_RenderState.mViewMatrix.multMatrixPoint(worldPos, eyePos);
-
-	if (gl_light_math != 0)
-	{
-		// Move light up because flasks/vials have their light source location at/below the floor.
-		//
-		// If the point is exactly on the wall plane it might cause some acne as some pixels could
-		// be in front and some behind. Move light just a tiny bit to avoid this.
-		eyePos[0] += 0.01f;
-		eyePos[1] += 5.01f;
-		eyePos[2] += 0.01f;
-	}
-
 	float *data = &ldata.arrays[i][ldata.arrays[i].Reserve(8)];
-	data[0] = eyePos[0];
-	data[1] = eyePos[1];
-	data[2] = eyePos[2];
+	data[0] = pos.X;
+	data[1] = pos.Z;
+	data[2] = pos.Y;
 	data[3] = radius;
 	data[4] = r;
 	data[5] = g;
diff --git a/src/gl/renderer/gl_renderstate.cpp b/src/gl/renderer/gl_renderstate.cpp
index cfaaea3cc..fa8237cca 100644
--- a/src/gl/renderer/gl_renderstate.cpp
+++ b/src/gl/renderer/gl_renderstate.cpp
@@ -158,7 +158,6 @@ bool FRenderState::ApplyShader()
 	activeShader->muTimer.Set(gl_frameMS * mShaderTimer / 1000.f);
 	activeShader->muAlphaThreshold.Set(mAlphaThreshold);
 	activeShader->muLightIndex.Set(mLightIndex);	// will always be -1 for now
-	activeShader->muLightMath.Set(gl_light_math);
 	activeShader->muClipSplit.Set(mClipSplit);
 
 	if (mGlowEnabled)
diff --git a/src/gl/shaders/gl_shader.cpp b/src/gl/shaders/gl_shader.cpp
index 9368a268c..9cbd69ce2 100644
--- a/src/gl/shaders/gl_shader.cpp
+++ b/src/gl/shaders/gl_shader.cpp
@@ -220,7 +220,6 @@ bool FShader::Load(const char * name, const char * vert_prog_lump, const char *
 	muColormapStart.Init(hShader, "uFixedColormapStart");
 	muColormapRange.Init(hShader, "uFixedColormapRange");
 	muLightIndex.Init(hShader, "uLightIndex");
-	muLightMath.Init(hShader, "uLightMath");
 	muFogColor.Init(hShader, "uFogColor");
 	muDynLightColor.Init(hShader, "uDynLightColor");
 	muObjectColor.Init(hShader, "uObjectColor");
diff --git a/src/gl/shaders/gl_shader.h b/src/gl/shaders/gl_shader.h
index 934674cbe..acdd530aa 100644
--- a/src/gl/shaders/gl_shader.h
+++ b/src/gl/shaders/gl_shader.h
@@ -266,7 +266,6 @@ class FShader
 	FUniform1i muFixedColormap;
 	FUniform4f muColormapStart;
 	FUniform4f muColormapRange;
-	FBufferedUniform1i muLightMath;
 	FBufferedUniform1i muLightIndex;
 	FBufferedUniformPE muFogColor;
 	FBufferedUniform4f muDynLightColor;
diff --git a/src/gl/system/gl_cvars.h b/src/gl/system/gl_cvars.h
index b7ac9e435..836787117 100644
--- a/src/gl/system/gl_cvars.h
+++ b/src/gl/system/gl_cvars.h
@@ -26,7 +26,6 @@ EXTERN_CVAR (Bool, gl_attachedlights);
 EXTERN_CVAR (Bool, gl_lights_checkside);
 EXTERN_CVAR (Bool, gl_light_sprites);
 EXTERN_CVAR (Bool, gl_light_particles);
-EXTERN_CVAR (Int, gl_light_math);
 
 EXTERN_CVAR(Int, gl_fogmode)
 EXTERN_CVAR(Int, gl_lightmode)
diff --git a/wadsrc/static/menudef.zz b/wadsrc/static/menudef.zz
index 6eb56be94..d5c2bbc5c 100644
--- a/wadsrc/static/menudef.zz
+++ b/wadsrc/static/menudef.zz
@@ -25,13 +25,6 @@ OptionValue "FilterModes"
 	4, "$OPTVAL_TRILINEAR"
 }
 
-OptionValue "LightMathModes"
-{
-	0, "$OPTVAL_LOW"
-	1, "$OPTVAL_MEDIUM"
-	2, "$OPTVAL_HIGH"
-}
-
 OptionValue "HWGammaModes"
 {
 	0, "$OPTVAL_ON"
@@ -225,7 +218,6 @@ OptionMenu "GLLightOptions"
 	Option "$GLLIGHTMNU_CLIPLIGHTS",		gl_lights_checkside,			"YesNo"
 	Option "$GLLIGHTMNU_LIGHTSPRITES",		gl_light_sprites,				"YesNo"
 	Option "$GLLIGHTMNU_LIGHTPARTICLES",	gl_light_particles,				"YesNo"
-	Option "$GLLIGHTMNU_LIGHTMATH",			gl_light_math,					"LightMathModes"
 }
 
 OptionMenu "GLPrefOptions"
diff --git a/wadsrc/static/shaders/glsl/main.fp b/wadsrc/static/shaders/glsl/main.fp
index 374edb59c..1f270728d 100644
--- a/wadsrc/static/shaders/glsl/main.fp
+++ b/wadsrc/static/shaders/glsl/main.fp
@@ -30,88 +30,6 @@ vec4 Process(vec4 color);
 vec4 ProcessTexel();
 vec4 ProcessLight(vec4 color);
 
-// Smoothed normal used for the face, in eye space. Should be converted to an 'in' variable in the future.
-vec3 pixelnormal;
-
-//===========================================================================
-//
-// Calculates the face normal vector for the fragment, in eye space
-//
-//===========================================================================
-
-vec3 calculateFaceNormal()
-{
-#if __VERSION__ < 450
-	vec3 dFdxPos = dFdx(pixelpos.xyz);
-	vec3 dFdyPos = dFdy(pixelpos.xyz);
-#else
-	vec3 dFdxPos = dFdxCoarse(pixelpos.xyz);
-	vec3 dFdyPos = dFdyCoarse(pixelpos.xyz);
-#endif
-	return normalize(cross(dFdxPos,dFdyPos));
-}
-
-//===========================================================================
-//
-// Standard lambertian diffuse light calculation
-//
-//===========================================================================
-
-float diffuseContribution(vec3 eyeLightDirection, vec3 eyeNormal)
-{
-	return max(dot(eyeNormal, eyeLightDirection), 0.0f);
-}
-
-//===========================================================================
-//
-// Blinn specular light calculation
-//
-//===========================================================================
-
-float blinnSpecularContribution(float diffuseContribution, vec3 eyeLightDirection, vec3 eyePosition, vec3 eyeNormal, float glossiness, float specularLevel)
-{
-	if (diffuseContribution > 0.0f)
-	{
-		vec3 viewDir = normalize(-eyePosition);
-		vec3 halfDir = normalize(eyeLightDirection + viewDir);
-		float specAngle = max(dot(halfDir, eyeNormal), 0.0f);
-		float phExp = glossiness * 4.0f;
-		return specularLevel * pow(specAngle, phExp);
-	}
-	else
-	{
-		return 0.0f;
-	}
-}
-
-//===========================================================================
-//
-// Calculates the brightness of a dynamic point light
-//
-//===========================================================================
-
-float pointLightAttenuation(vec4 lightpos)
-{
-	float attenuation = max(lightpos.w - distance(pixelpos.xyz, lightpos.xyz),0.0) / lightpos.w;
-	if (uLightMath == 0)
-	{
-		return attenuation;
-	}
-	else
-	{
-		vec3 lightDirection = normalize(lightpos.xyz - pixelpos.xyz);
-		float diffuseAmount = diffuseContribution(lightDirection, pixelnormal);
-		if (uLightMath == 1)
-		{
-			return attenuation * diffuseAmount;
-		}
-		else
-		{
-			float specularAmount = blinnSpecularContribution(diffuseAmount, lightDirection, pixelpos.xyz, pixelnormal, 3.0, 1.2);
-			return attenuation * (diffuseAmount + specularAmount);
-		}
-	}
-}
 
 //===========================================================================
 //
@@ -384,13 +302,6 @@ vec3 AmbientOcclusionColor()
 void main()
 {
 	vec4 frag = ProcessTexel();
-
-#if defined NUM_UBO_LIGHTS || defined SHADER_STORAGE_LIGHTS
-	if (uLightMath != 0) // Remove this if pixelnormal is converted to an 'in' variable
-	{
-		pixelnormal = calculateFaceNormal();
-	}
-#endif
 	
 #ifndef NO_ALPHATEST
 	if (frag.a <= uAlphaThreshold) discard;
@@ -416,11 +327,12 @@ void main()
 				}
 				else 
 				{
-					fogdist = max(16.0, length(pixelpos.xyz));
+					fogdist = max(16.0, distance(pixelpos.xyz, uCameraPos.xyz));
 				}
 				fogfactor = exp2 (uFogDensity * fogdist);
 			}
 			
+			
 			frag *= getLightColor(fogdist, fogfactor);
 			
 #if defined NUM_UBO_LIGHTS || defined SHADER_STORAGE_LIGHTS
@@ -486,7 +398,7 @@ void main()
 			}
 			else 
 			{
-				fogdist = max(16.0, length(pixelpos.xyz));
+				fogdist = max(16.0, distance(pixelpos.xyz, uCameraPos.xyz));
 			}
 			fogfactor = exp2 (uFogDensity * fogdist);
 			
diff --git a/wadsrc/static/shaders/glsl/main.vp b/wadsrc/static/shaders/glsl/main.vp
index 0baca31f9..1de8854c0 100644
--- a/wadsrc/static/shaders/glsl/main.vp
+++ b/wadsrc/static/shaders/glsl/main.vp
@@ -47,7 +47,7 @@ void main()
 	vColor = aColor;
 
 	#ifndef SIMPLE
-		pixelpos.xyz = eyeCoordPos.xyz;
+		pixelpos.xyz = worldcoord.xyz;
 		pixelpos.w = -eyeCoordPos.z/eyeCoordPos.w;
 
 		glowdist.x = -((uGlowTopPlane.w + uGlowTopPlane.x * worldcoord.x + uGlowTopPlane.y * worldcoord.z) * uGlowTopPlane.z) - worldcoord.y;
diff --git a/wadsrc/static/shaders/glsl/shaderdefs.i b/wadsrc/static/shaders/glsl/shaderdefs.i
index 81edd7b04..8c5697a66 100644
--- a/wadsrc/static/shaders/glsl/shaderdefs.i
+++ b/wadsrc/static/shaders/glsl/shaderdefs.i
@@ -44,7 +44,6 @@ uniform int uFogEnabled;
 
 // dynamic lights
 uniform int uLightIndex;
-uniform int uLightMath;				// 0, when using only attenuation, 1 for diffuse light, 2 for blinn specular light
 
 // quad drawer stuff
 #ifdef USE_QUAD_DRAWER