a-game

commit 49da3252faeb1e5d9497604c6ce1153295abcbfd
parent 6566a9dcf2f15f4b1965db677de28409fa720d27
Author: Amin Mesbah <dev@aminmesbah.com>
Date:   Thu,  4 Jul 2019 18:52:08 -0700

Flip the image right side up

Diffstat:
M
src/game.c
 | 
15
+++++++++++++++

1 file changed, 15 insertions(+), 0 deletions(-)
diff --git a/src/game.c b/src/game.c
@@ -72,6 +72,21 @@ internal u8 *img_load_from_memory(u8 *buffer, size_t len, i32 *out_width, i32 *o
         pixels[i] = *buffer++;
     }
 
+    u32 bytes_per_row = h.width * bytes_per_pixel;
+    // NOTE(amin): Intentional truncating division. If height is odd, we want
+    // our last row offset to be 1 less than the middle row.
+    u32 half_height = h.height / 2;
+    for (size_t row_offset = 0; row_offset < half_height; row_offset++)
+    {
+        u8 *top_row = &pixels[row_offset * bytes_per_row];
+        u8 *bot_row = &pixels[(h.height - row_offset - 1) * bytes_per_row];
+        for (size_t i = 0; i < bytes_per_row; i++)
+        {
+            u8 temp = top_row[i];
+            top_row[i] = bot_row[i];
+            bot_row[i] = temp;
+        }
+    }
     return pixels;
 }