diff --git a/src/rendering/polyrenderer/drawers/screen_blend.cpp b/src/rendering/polyrenderer/drawers/screen_blend.cpp
index 9dee914ca..a8a7d1a8d 100644
--- a/src/rendering/polyrenderer/drawers/screen_blend.cpp
+++ b/src/rendering/polyrenderer/drawers/screen_blend.cpp
@@ -547,6 +547,10 @@ void BlendColorColormap(int y, int x0, int x1, PolyTriangleThreadData* thread)
 		g = (startG + ((gray * rangeG) >> 8)) << 1;
 		b = (startB + ((gray * rangeB) >> 8)) << 1;
 
+		r = MIN(r, (uint32_t)255);
+		g = MIN(g, (uint32_t)255);
+		b = MIN(b, (uint32_t)255);
+
 		line[x] = MAKEARGB(a, r, g, b);
 	}
 }
diff --git a/src/rendering/polyrenderer/drawers/screen_shader.cpp b/src/rendering/polyrenderer/drawers/screen_shader.cpp
index aec34f3e0..af23172a6 100644
--- a/src/rendering/polyrenderer/drawers/screen_shader.cpp
+++ b/src/rendering/polyrenderer/drawers/screen_shader.cpp
@@ -561,6 +561,10 @@ static void MainFP(int x0, int x1, PolyTriangleThreadData* thread)
 				g = (startG + ((gray * rangeG) >> 8)) << 1;
 				b = (startB + ((gray * rangeB) >> 8)) << 1;
 
+				r = MIN(r, (uint32_t)255);
+				g = MIN(g, (uint32_t)255);
+				b = MIN(b, (uint32_t)255);
+
 				fragcolor[x] = MAKEARGB(a, r, g, b);
 			}
 		}