From b0ca322b3f9aaa4eeb06c28569d0f2d66940f882 Mon Sep 17 00:00:00 2001
From: Misa <infoteddy@infoteddy.info>
Date: Mon, 2 Jan 2023 10:44:35 -0800
Subject: [PATCH] Use SDL_GetRGBA and SDL_MapRGBA to read and draw pixels

Honestly not too sure why we ever wrote the mask handling logic
ourselves instead of using SDL functions. Hell, we even used SDL_MapRGB
for Graphics::getRGB before.
---
 desktop_version/src/GraphicsUtil.cpp | 26 ++++----------------------
 1 file changed, 4 insertions(+), 22 deletions(-)

diff --git a/desktop_version/src/GraphicsUtil.cpp b/desktop_version/src/GraphicsUtil.cpp
index 92ca330d..23f5c143 100644
--- a/desktop_version/src/GraphicsUtil.cpp
+++ b/desktop_version/src/GraphicsUtil.cpp
@@ -94,11 +94,6 @@ static void DrawPixel(SDL_Surface* surface, const int x, const int y, const SDL_
     const SDL_PixelFormat* fmt = surface->format;
     const int bpp = fmt->BytesPerPixel;
     Uint32* pixel = (Uint32*) ((Uint8*) surface->pixels + y * surface->pitch + x * bpp);
-    const Uint32 packed =
-        (color.r << fmt->Rshift) |
-        (color.g << fmt->Gshift) |
-        (color.b << fmt->Bshift) |
-        (color.a << fmt->Ashift);
 
     switch (bpp)
     {
@@ -109,8 +104,7 @@ static void DrawPixel(SDL_Surface* surface, const int x, const int y, const SDL_
         return;
 
     case 4:
-        *pixel = packed;
-        break;
+        *pixel = SDL_MapRGBA(fmt, color.r, color.g, color.b, color.a);
     }
 }
 
@@ -119,32 +113,20 @@ SDL_Color ReadPixel(const SDL_Surface* surface, const int x, const int y)
     const SDL_PixelFormat* fmt = surface->format;
     const int bpp = surface->format->BytesPerPixel;
     const Uint32* pixel = (Uint32*) ((Uint8*) surface->pixels + y * surface->pitch + x * bpp);
+    SDL_Color color = {0, 0, 0, 0};
 
     switch (bpp)
     {
     case 1:
     case 2:
     case 3:
-    {
         SDL_assert(0 && "Non-32-bit colors not supported!");
-        const SDL_Color color = {0, 0, 0, 0};
-        return color;
-    }
+        break;
 
     case 4:
-    {
-        const SDL_Color color = {
-            (Uint8) ((*pixel & fmt->Rmask) >> fmt->Rshift),
-            (Uint8) ((*pixel & fmt->Gmask) >> fmt->Gshift),
-            (Uint8) ((*pixel & fmt->Bmask) >> fmt->Bshift),
-            (Uint8) ((*pixel & fmt->Amask) >> fmt->Ashift)
-        };
-        return color;
-    }
+        SDL_GetRGBA(*pixel, fmt, &color.r, &color.g, &color.b, &color.a);
     }
 
-    /* shouldn't happen, but avoids warnings */
-    const SDL_Color color = {0, 0, 0, 0};
     return color;
 }