diff --git a/src/swrenderer/scene/r_light.cpp b/src/swrenderer/scene/r_light.cpp
index 5be847bf8d..fa9ae27f93 100644
--- a/src/swrenderer/scene/r_light.cpp
+++ b/src/swrenderer/scene/r_light.cpp
@@ -145,6 +145,11 @@ namespace swrenderer
 		FloorVisibility = 160.0 * FloorVisibility / viewport->FocalLengthY;
 
 		TiltVisibility = float(vis * FocalTangent * (16.f * 320.f) / viewwidth);
+
+		// Disable diminishing light (To do: make a cvar control this)
+		WallVisibility = 0.0;
+		FloorVisibility = 0.0;
+		TiltVisibility = 0.0f;
 	}
 
 	// Controls how quickly light ramps across a 1/z range. Set this, and it
diff --git a/src/swrenderer/scene/r_light.h b/src/swrenderer/scene/r_light.h
index fd919fba15..7b127acb2e 100644
--- a/src/swrenderer/scene/r_light.h
+++ b/src/swrenderer/scene/r_light.h
@@ -32,7 +32,10 @@
 // Convert a light level into an unbounded colormap index (shade). Result is
 // fixed point. Why the +12? I wish I knew, but experimentation indicates it
 // is necessary in order to best reproduce Doom's original lighting.
-#define LIGHT2SHADE(l) ((NUMCOLORMAPS*2*FRACUNIT)-(((l)+12)*(FRACUNIT*NUMCOLORMAPS/128)))
+//#define LIGHT2SHADE(l) ((NUMCOLORMAPS*2*FRACUNIT)-(((l)+12)*(FRACUNIT*NUMCOLORMAPS/128)))
+
+// Disable diminishing light (To do: merge with LIGHT2SHADE and let a cvar control it, maybe by converting this to a function, like R_ActualExtraLight)
+#define LIGHT2SHADE(lightlev) ((MAX(255 - lightlev, 0) * NUMCOLORMAPS) << (FRACBITS - 8))
 
 // MAXLIGHTSCALE from original DOOM, divided by 2.
 #define MAXLIGHTVIS (24.0)