Make all drawing happen to a viewport

We now have an inner and outer viewport, and entity positions are
relative to the inner one while drawing happens to the outer one.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/display/mod.rs b/src/display/mod.rs
index 5dba48b44d9a..664aaf319cc7 100644
--- a/src/display/mod.rs
+++ b/src/display/mod.rs
@@ -1,9 +1,18 @@
 pub mod draw_box;
 pub mod utils;
+pub mod viewport;
+use crate::types::Positioned;
 pub use draw_box::{make_box, BoxStyle};
 use std::io::{self, Write};
 use termion::{clear, cursor, style};
+pub use viewport::Viewport;
 
 pub fn clear<T: Write>(out: &mut T) -> io::Result<()> {
     write!(out, "{}{}{}", clear::All, style::Reset, cursor::Goto(1, 1))
 }
+
+pub trait Draw: Positioned {
+    /// Draw this entity, assuming the character is already at the correct
+    /// position
+    fn do_draw<W: Write>(&self, out: &mut W) -> io::Result<()>;
+}