diff --git a/Source/diablo.cpp b/Source/diablo.cpp
index 198dbee28..9eb86785f 100644
--- a/Source/diablo.cpp
+++ b/Source/diablo.cpp
@@ -1908,11 +1908,11 @@ void timeout_cursor(BOOL bTimeout)
 
 void diablo_color_cyc_logic()
 {
-	DWORD v0; // eax
+	DWORD tc;
 
-	v0 = GetTickCount();
-	if (v0 - color_cycle_timer >= 0x32) {
-		color_cycle_timer = v0;
+	tc = GetTickCount();
+	if (tc - color_cycle_timer >= 0x32) {
+		color_cycle_timer = tc;
 		if (palette_get_colour_cycling()) {
 			if (leveltype == DTYPE_HELL) {
 				lighting_color_cycling();
diff --git a/Source/palette.cpp b/Source/palette.cpp
index 58df35d47..bcf4e68ab 100644
--- a/Source/palette.cpp
+++ b/Source/palette.cpp
@@ -280,12 +280,12 @@ void palette_update_quest_palette(int n)
 	palette_update();
 }
 
-BOOLEAN palette_get_colour_cycling()
+BOOL palette_get_colour_cycling()
 {
 	return color_cycling_enabled;
 }
 
-void palette_set_color_cycling(BOOLEAN enabled)
+void palette_set_color_cycling(BOOL enabled)
 {
 	color_cycling_enabled = enabled;
 }
diff --git a/Source/palette.h b/Source/palette.h
index d8e6e62d3..0306627c3 100644
--- a/Source/palette.h
+++ b/Source/palette.h
@@ -25,8 +25,8 @@ void PaletteFadeIn(int fr);
 void PaletteFadeOut(int fr);
 void palette_update_caves();
 void palette_update_quest_palette(int n);
-BOOLEAN palette_get_colour_cycling();
-void palette_set_color_cycling(BOOLEAN enabled);
+BOOL palette_get_colour_cycling();
+void palette_set_color_cycling(BOOL enabled);
 
 /* rdata */