diff --git a/src/devices/video/voodoo_render.cpp b/src/devices/video/voodoo_render.cpp
index ef9a75bd673..4ad88890275 100644
--- a/src/devices/video/voodoo_render.cpp
+++ b/src/devices/video/voodoo_render.cpp
@@ -1211,9 +1211,9 @@ void rasterizer_palette::compute_ncc(u32 const *regs)
 		s32 q = regs[8 + BIT(index, 0, 2)];
 
 		// add the coloring
-		s32 r = std::clamp(y + (s32(i <<  5) >> 23) + (s32(q <<  5) >> 23), 0, 255);
-		s32 g = std::clamp(y + (s32(i << 14) >> 23) + (s32(q << 14) >> 23), 0, 255);
-		s32 b = std::clamp(y + (s32(i << 23) >> 23) + (s32(q << 23) >> 23), 0, 255);
+		s32 r = std::clamp(y + util::sext(i >> 18, 9) + util::sext(q >> 18, 9), 0, 255);
+		s32 g = std::clamp(y + util::sext(i >>  9, 9) + util::sext(q >>  9, 9), 0, 255);
+		s32 b = std::clamp(y + util::sext(i      , 9) + util::sext(q      , 9), 0, 255);
 
 		// fill in the table
 		m_texel[index] = rgb_t(0xff, r, g, b);
@@ -1372,7 +1372,7 @@ inline bool ATTR_FORCE_INLINE voodoo_renderer::stipple_test(thread_stats_block &
 	// rotate mode
 	if (fbzmode.stipple_pattern() == 0)
 	{
-		stipple = (stipple >> 1) | (stipple << 31);
+		stipple = rotr_32(stipple, 1);
 		if (s32(stipple) >= 0)
 		{
 			threadstats.stipple_count++;