From 4a0042ba1563b8d2f0669c7650e997b6c1a9d95e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Sun, 28 Jun 2020 09:16:43 +0200
Subject: [PATCH] sixel: insert: sort sixels such that those furthest up in the
 scrollback is at the back

---
 sixel.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/sixel.c b/sixel.c
index 3c6d67af..ddb0091c 100644
--- a/sixel.c
+++ b/sixel.c
@@ -90,6 +90,25 @@ sixel_erase(struct terminal *term, struct sixel *sixel)
 static void
 sixel_insert(struct terminal *term, struct sixel sixel)
 {
+    const int scrollback_end
+        = (term->grid->offset + term->rows) & (term->grid->num_rows - 1);
+
+    int end_row = sixel.pos.row + sixel.rows - scrollback_end;
+    while (end_row < 0)
+        end_row += term->grid->num_rows;
+
+    tll_foreach(term->grid->sixel_images, it) {
+        int e = it->item.pos.row + it->item.rows - scrollback_end;
+        e -= scrollback_end;
+        while (e < 0)
+            e += term->grid->num_rows;
+
+        if (e < end_row) {
+            tll_insert_before(term->grid->sixel_images, it, sixel);
+            return;
+        }
+    }
+
     tll_push_back(term->grid->sixel_images, sixel);
 }