diff --git a/source/glbackend/gl_shader.cpp b/source/glbackend/gl_shader.cpp
index fe592d8a0..7b6ad7bfd 100644
--- a/source/glbackend/gl_shader.cpp
+++ b/source/glbackend/gl_shader.cpp
@@ -138,8 +138,9 @@ bool PolymostShader::Load(const char * name, const char * vert_prog, const char
     NPOTEmulationFactor.Init(hShader, "u_npotEmulationFactor");
     NPOTEmulationXOffset.Init(hShader, "u_npotEmulationXOffset");
     Brightness.Init(hShader, "u_brightness");
-	FogColor.Init(hShader, "u_fogColor");
 
+	TextureMode.Init(hShader, "uTextureMode");
+	FogColor.Init(hShader, "uFogColor");
 	muFogEnabled.Init(hShader, "uFogEnabled");
 	muLightParms.Init(hShader, "uLightAttr");
 	AlphaThreshold.Init(hShader, "uAlphaThreshold");
@@ -160,11 +161,11 @@ bool PolymostShader::Load(const char * name, const char * vert_prog, const char
 	int SamplerLoc;
     SamplerLoc = glGetUniformLocation(hShader, "s_texture");
 	glUniform1i(SamplerLoc, 0);
-	SamplerLoc = glGetUniformLocation(hShader, "s_brightmap");
+	SamplerLoc = glGetUniformLocation(hShader, "brighttexture");
 	glUniform1i(SamplerLoc, 1);
-	SamplerLoc = glGetUniformLocation(hShader, "s_detail");
+	SamplerLoc = glGetUniformLocation(hShader, "detailtexture");
 	glUniform1i(SamplerLoc, 2);
-	SamplerLoc = glGetUniformLocation(hShader, "s_glow");
+	SamplerLoc = glGetUniformLocation(hShader, "glowtexture");
 	glUniform1i(SamplerLoc, 3);
 	SamplerLoc = glGetUniformLocation(hShader, "s_palette");
 	glUniform1i(SamplerLoc, 4);
diff --git a/source/glbackend/gl_shader.h b/source/glbackend/gl_shader.h
index 8873ec6a6..10860632b 100644
--- a/source/glbackend/gl_shader.h
+++ b/source/glbackend/gl_shader.h
@@ -32,6 +32,7 @@ public:
     FBufferedUniform1f Brightness;
 	FBufferedUniformPalEntry FogColor;
 
+	FBufferedUniform1i TextureMode;
 	FBufferedUniform4f DetailParms;
 	FBufferedUniform1f AlphaThreshold;
 	FBufferedUniform1i muFogEnabled;
diff --git a/source/glbackend/glbackend.cpp b/source/glbackend/glbackend.cpp
index 9dd44d7ad..8ccb4059c 100644
--- a/source/glbackend/glbackend.cpp
+++ b/source/glbackend/glbackend.cpp
@@ -116,6 +116,10 @@ auto i_data = R"(
 		float uClipHeightDirection;
 		int uShadowmapFilter;
 	};
+	uniform sampler2D detailtexture;
+	uniform sampler2D glowtexture;
+	uniform sampler2D brighttexture;
+
 	uniform mat4 ModelMatrix;
 	uniform mat4 NormalModelMatrix;
 	uniform mat4 TextureMatrix;
@@ -132,6 +136,8 @@ auto i_data = R"(
 	#define uLightFactor uLightAttr.g
 	#define uLightDist uLightAttr.r
 	uniform int uFogEnabled;
+	uniform vec4 uFogColor;
+	uniform int uTextureMode;
 
 )";
 
@@ -543,7 +549,7 @@ void PolymostRenderState::Apply(PolymostShader* shader, GLState& oldState)
 	shader->AlphaThreshold.Set(AlphaTest ? AlphaThreshold : -1.f);
 	shader->Brightness.Set(Brightness);
 	shader->FogColor.Set(FogColor);
-	float lightattr[] = { ShadeDiv / (numshades - 2), VisFactor, (Flags & RF_MapFog) ? -5.f : 0.f , Shade };
+	float lightattr[] = { ShadeDiv / (numshades - 2), VisFactor, (Flags & RF_MapFog) ? -5.f : 0.f , ShadeDiv >= 1 / 1000.f? Shade : 0 };
 	shader->muLightParms.Set(lightattr);
 
 	FVector4 addcol(0, 0, 0, 0);
diff --git a/wadsrc/static/engine/shaders/glsl/polymost.fp b/wadsrc/static/engine/shaders/glsl/polymost.fp
index 81874d2bd..dc2a1759c 100644
--- a/wadsrc/static/engine/shaders/glsl/polymost.fp
+++ b/wadsrc/static/engine/shaders/glsl/polymost.fp
@@ -13,16 +13,11 @@ uniform sampler2D s_palswap;
 //s_palette is the base palette texture where u is the color index
 uniform sampler2D s_palette;
 
-uniform sampler2D s_detail;
-uniform sampler2D s_glow;
-uniform sampler2D s_brightmap;
-
 uniform int u_flags;
 
 uniform float u_npotEmulationFactor;
 uniform float u_npotEmulationXOffset;
 uniform float u_brightness;
-uniform vec4 u_fogColor;
 
 in vec4 v_color;
 in float v_distance;
@@ -165,7 +160,7 @@ void main()
 		vec4 detailColor = vec4(1.0);
 		if ((u_flags & RF_DetailMapping) != 0)
 		{
-			detailColor = texture(s_detail, newCoord * uDetailParms.xy) * uDetailParms.z;
+			detailColor = texture(detailtexture, newCoord * uDetailParms.xy) * uDetailParms.z;
 			detailColor = mix(vec4(1.0), 2.0 * detailColor, detailColor.a);
 			// Application of this differs based on render mode because for paletted rendering with palettized shade tables it can only be done after processing the shade table. We only have a palette index before.
 		}
@@ -217,10 +212,10 @@ void main()
 
 				if ((u_flags & RF_Brightmapping) != 0)
 				{
-					lightcolor = clamp(lightcolor + texture(s_brightmap, v_texCoord.xy).rgb, 0.0, 1.0);
+					lightcolor = clamp(lightcolor + texture(brighttexture, v_texCoord.xy).rgb, 0.0, 1.0);
 				}
 				color.rgb *= lightcolor;
-				if (uFogDensity == 0.0) color.rgb += u_fogColor.rgb * shade;
+				if (uFogDensity == 0.0) color.rgb += uFogColor.rgb * shade;
 			}
 			else color.rgb *= v_color.rgb;
 		}
@@ -241,7 +236,7 @@ void main()
 
 	if ((u_flags & (RF_ColorOnly|RF_GlowMapping)) == RF_GlowMapping)
 	{
-		vec4 glowColor = texture(s_glow, v_texCoord.xy);
+		vec4 glowColor = texture(glowtexture, v_texCoord.xy);
 		color.rgb = mix(color.rgb, glowColor.rgb, glowColor.a);
 	}