From 37bea25b01be5cf970882e9b9f21a411fabcc4bf Mon Sep 17 00:00:00 2001
From: Phlosioneer <mattmdrr2@gmail.com>
Date: Sat, 9 Feb 2019 21:50:12 -0500
Subject: [PATCH] Name the possible return values of palette fading functions

Also replace implicit conversion from gPalette.active into a status with
if statements, to make the return value clear.

I've also added comments when the check is redundant.
---
 include/palette.h |  5 +++++
 src/palette.c     | 33 +++++++++++++++++++++------------
 2 files changed, 26 insertions(+), 12 deletions(-)

diff --git a/include/palette.h b/include/palette.h
index e24da3e00..84794afc9 100644
--- a/include/palette.h
+++ b/include/palette.h
@@ -9,6 +9,11 @@
 #define PLTT_BUFFER_SIZE 0x200
 #define PLTT_DECOMP_BUFFER_SIZE (PLTT_BUFFER_SIZE * 2)
 
+#define PALETTE_FADE_STATUS_DELAY 2
+#define PALETTE_FADE_STATUS_ACTIVE 1
+#define PALETTE_FADE_STATUS_DONE 0
+#define PALETTE_FADE_STATUS_LOADING -1
+
 enum
 {
     FAST_FADE_IN_FROM_WHITE,
diff --git a/src/palette.c b/src/palette.c
index be5143876..5d1d6635c 100644
--- a/src/palette.c
+++ b/src/palette.c
@@ -115,7 +115,7 @@ u8 UpdatePaletteFade(void)
     u8 dummy = 0;
 
     if (sPlttBufferTransferPending)
-        return -1;
+        return PALETTE_FADE_STATUS_LOADING;
 
     if (gPaletteFade.mode == NORMAL_FADE)
         result = UpdateNormalPaletteFade();
@@ -409,11 +409,11 @@ static u8 UpdateNormalPaletteFade(void)
     u16 selectedPalettes;
 
     if (!gPaletteFade.active)
-        return 0;
+        return PALETTE_FADE_STATUS_DONE;
 
     if (IsSoftwarePaletteFadeFinishing())
     {
-        return gPaletteFade.active;
+        return gPaletteFade.active ? PALETTE_FADE_STATUS_ACTIVE : PALETTE_FADE_STATUS_DONE;
     }
     else
     {
@@ -483,7 +483,9 @@ static u8 UpdateNormalPaletteFade(void)
             }
         }
 
-        return gPaletteFade.active;
+        // gPaletteFade.active cannot change since the last time it was checked. So this
+        // is equivalent to `return PALETTE_FADE_STATUS_ACTIVE;`
+        return gPaletteFade.active ? PALETTE_FADE_STATUS_ACTIVE : PALETTE_FADE_STATUS_DONE;
     }
 }
 
@@ -578,10 +580,11 @@ static u8 UpdateFastPaletteFade(void)
     s8 b;
 
     if (!gPaletteFade.active)
-        return 0;
+        return PALETTE_FADE_STATUS_DONE;
 
     if (IsSoftwarePaletteFadeFinishing())
-        return gPaletteFade.active;
+        return gPaletteFade.active ? PALETTE_FADE_STATUS_ACTIVE : PALETTE_FADE_STATUS_DONE;
+        
 
     if (gPaletteFade.objPaletteToggle)
     {
@@ -688,7 +691,9 @@ static u8 UpdateFastPaletteFade(void)
     gPaletteFade.objPaletteToggle ^= 1;
 
     if (gPaletteFade.objPaletteToggle)
-        return gPaletteFade.active;
+        // gPaletteFade.active cannot change since the last time it was checked. So this
+        // is equivalent to `return PALETTE_FADE_STATUS_ACTIVE;`
+        return gPaletteFade.active ? PALETTE_FADE_STATUS_ACTIVE : PALETTE_FADE_STATUS_DONE;
 
     if (gPaletteFade.y - gPaletteFade.deltaY < 0)
         gPaletteFade.y = 0;
@@ -714,8 +719,10 @@ static u8 UpdateFastPaletteFade(void)
         gPaletteFade.mode = NORMAL_FADE;
         gPaletteFade.softwareFadeFinishing = 1;
     }
-
-    return gPaletteFade.active;
+    
+    // gPaletteFade.active cannot change since the last time it was checked. So this
+    // is equivalent to `return PALETTE_FADE_STATUS_ACTIVE;`
+    return gPaletteFade.active ? PALETTE_FADE_STATUS_ACTIVE : PALETTE_FADE_STATUS_DONE;
 }
 
 void BeginHardwarePaletteFade(u8 blendCnt, u8 delay, u8 y, u8 targetY, u8 shouldResetBlendRegisters)
@@ -739,12 +746,12 @@ void BeginHardwarePaletteFade(u8 blendCnt, u8 delay, u8 y, u8 targetY, u8 should
 static u8 UpdateHardwarePaletteFade(void)
 {
     if (!gPaletteFade.active)
-        return 0;
+        return PALETTE_FADE_STATUS_DONE;
 
     if (gPaletteFade.delayCounter < gPaletteFade_delay)
     {
         gPaletteFade.delayCounter++;
-        return 2;
+        return PALETTE_FADE_STATUS_DELAY;
     }
 
     gPaletteFade.delayCounter = 0;
@@ -778,7 +785,9 @@ static u8 UpdateHardwarePaletteFade(void)
         gPaletteFade.shouldResetBlendRegisters = 0;
     }
 
-    return gPaletteFade.active;
+    // gPaletteFade.active cannot change since the last time it was checked. So this
+    // is equivalent to `return PALETTE_FADE_STATUS_ACTIVE;`
+    return gPaletteFade.active ? PALETTE_FADE_STATUS_ACTIVE : PALETTE_FADE_STATUS_DONE;
 }
 
 static void UpdateBlendRegisters(void)