From 3b9909ad5b92799593fb050421347195959f416c Mon Sep 17 00:00:00 2001
From: Gwilym Kuiper <gw@ilym.me>
Date: Tue, 3 May 2022 23:43:08 +0100
Subject: [PATCH] Add comment about how silly the implementation of gba_offset
 is

---
 agb/src/display/tiled/mod.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/agb/src/display/tiled/mod.rs b/agb/src/display/tiled/mod.rs
index 68ae2e9..1590779 100644
--- a/agb/src/display/tiled/mod.rs
+++ b/agb/src/display/tiled/mod.rs
@@ -53,6 +53,8 @@ impl RegularBackgroundSize {
         self.num_tiles() / (32 * 32)
     }
 
+    // This is hilariously complicated due to how the GBA stores the background screenblocks.
+    // See https://www.coranac.com/tonc/text/regbg.htm#sec-map for an explanation
     pub(crate) fn gba_offset(&self, pos: Vector2D<u16>) -> usize {
         let x_mod = pos.x & (self.width() as u16 - 1);
         let y_mod = pos.y & (self.height() as u16 - 1);