Implement scrolling

Buffer now scrolls correcly when reaching top or bottom and puts dot at
the middle of the screen.

1 files changed, 4 insertions, 1 deletions

diff --git a/src/buffer.h b/src/buffer.h
index 358aea5..92cc353 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -24,12 +24,15 @@ struct buffer {
   uint32_t nkeymaps;
   uint32_t nkeymaps_max;
 
-  uint32_t lines_rendered;
+  uint32_t scroll_line;
+  uint32_t scroll_col;
 };
 
 struct buffer_update {
   struct render_cmd *cmds;
   uint64_t ncmds;
+  uint32_t dot_col;
+  uint32_t dot_line;
 };
 
 typedef void *(alloc_fn)(size_t);