diff --git a/src/hardware/hw_main.c b/src/hardware/hw_main.c
index 066822e8c7d3128d2ade269aa8f0f47e7b5f55ae..5171ab435abbc2271e7027ed2a1c52d394dbd66a 100644
--- a/src/hardware/hw_main.c
+++ b/src/hardware/hw_main.c
@@ -1494,12 +1494,8 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 					transnum_t transtable = R_GetLinedefTransTable(gl_linedef);
 					if (transtable == NUMTRANSMAPS)
 						transtable = 0;
-					if (gl_linedef->special >= 910 && gl_linedef->special <= 919)
-						blend = AST_ADD;
-					else if (gl_linedef->special >= 920 && gl_linedef->special <= 929)
-						blend = AST_SUBTRACT;
-					else if (gl_linedef->special >= 930 && gl_linedef->special <= 939)
-						blend = AST_REVERSESUBTRACT;
+					if (gl_linedef->blendmode == AST_ADD || gl_linedef->blendmode == AST_SUBTRACT || gl_linedef->blendmode == AST_REVERSESUBTRACT)
+						blend = gl_linedef->blendmode;
 
 					blendmode = HWR_SurfaceBlend(blend, transtable, &Surf);
 					break;
diff --git a/src/p_setup.c b/src/p_setup.c
index 0ffc807f5fe2ddd58401f31c66e9dfcaadd2026e..744ec3c55f1d5ef0f06a7568b5598076f2bb9556 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -3156,6 +3156,18 @@ static void P_ConvertBinaryMap(void)
 		if (lines[i].special >= 910 && lines[i].special <= 939)
 			lines[i].alpha = ((10 - lines[i].special % 10) << FRACBITS)/10;
 
+		if (lines[i].special >= 910 && lines[i].special <= 919) // additive
+			lines[i].blendmode = AST_ADD;
+
+		if (lines[i].special >= 920 && lines[i].special <= 929) // subtractive
+			lines[i].blendmode = AST_SUBTRACT;
+
+		if (lines[i].special >= 930 && lines[i].special <= 939) // reverse subtractive
+			lines[i].blendmode = AST_REVERSESUBTRACT;
+
+		if (lines[i].special == 940) // modulate
+			lines[i].blendmode = AST_MODULATE;
+
 		//Linedef executor delay
 		if (lines[i].special >= 400 && lines[i].special < 500)
 		{
diff --git a/src/r_defs.h b/src/r_defs.h
index 681bb36198e466cc2c8dae1558c697111aca3699..16912fca1ecefabb44a607351658a86663c6e5b9 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -398,6 +398,7 @@ typedef struct line_s
 	// Visual appearance: sidedefs.
 	UINT16 sidenum[2]; // sidenum[1] will be 0xffff if one-sided
 	fixed_t alpha; // translucency
+	UINT8 blendmode; // blendmode
 	INT32 executordelay;
 
 	fixed_t bbox[4]; // bounding box for the extent of the linedef
diff --git a/src/r_segs.c b/src/r_segs.c
index 209810059e66dc419ecc344863071a4e6a5a2c1c..0b9c9a80edf9ce3763e10c2c36931d0c38b696c8 100644
--- a/src/r_segs.c
+++ b/src/r_segs.c
@@ -162,25 +162,13 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 		return;
 
 	transtable = R_GetLinedefTransTable(ldef);
-	if (ldef->special >= 910 && ldef->special <= 919)
+	if (ldef->blendmode == AST_ADD || ldef->blendmode == AST_SUBTRACT || ldef->blendmode == AST_REVERSESUBTRACT)
 	{
 		if (transtable == NUMTRANSMAPS)
 			transtable = 0;
-		blendmode = AST_ADD;
+		blendmode = ldef->blendmode;
 	}
-	else if (ldef->special >= 920 && ldef->special <= 929)
-	{
-		if (transtable == NUMTRANSMAPS)
-			transtable = 0;
-		blendmode = AST_SUBTRACT;
-	}
-	else if (ldef->special >= 930 && ldef->special <= 939)
-	{
-		if (transtable == NUMTRANSMAPS)
-			transtable = 0;
-		blendmode = AST_REVERSESUBTRACT;
-	}
-	else if (ldef->special == 940)
+	else if (ldef->blendmode == AST_MODULATE)
 	{
 		transtable = 0;
 		blendmode = AST_MODULATE;