From 9e650a95403034c413775e3d020afa9aa268bed9 Mon Sep 17 00:00:00 2001
From: Themaister <maister@archlinux.us>
Date: Sat, 9 Jun 2012 10:29:50 +0200
Subject: [PATCH] Add some clarifying comments on screenshots.

---
 retroarch.c  | 3 +++
 screenshot.c | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/retroarch.c b/retroarch.c
index 26a2432667..964c566a52 100644
--- a/retroarch.c
+++ b/retroarch.c
@@ -109,6 +109,7 @@ static bool take_screenshot_viewport(void)
       return false;
    }
 
+   // Data read from viewport is in bottom-up order, suitable for BMP.
    if (!screenshot_dump(g_settings.screenshot_directory,
          buffer,
          width, height, width * 3, true))
@@ -127,6 +128,8 @@ static bool take_screenshot_raw(void)
    unsigned height      = g_extern.frame_cache.height;
    int pitch            = g_extern.frame_cache.pitch;
 
+   // Negative pitch is needed as screenshot takes bottom-up,
+   // but we use top-down.
    return screenshot_dump(g_settings.screenshot_directory,
          data + (height - 1) * (pitch >> 1), 
          width, height, -pitch, false);
diff --git a/screenshot.c b/screenshot.c
index f7add52c6e..5be6b7d8df 100644
--- a/screenshot.c
+++ b/screenshot.c
@@ -85,7 +85,7 @@ static void dump_content(FILE *file, const void *frame,
    if (!line)
       return;
 
-   if (bgr24)
+   if (bgr24) // BGR24 byte order. Can directly copy.
    {
       for (int j = 0; j < height; j++, frame_bgr += pitch)
       {