From 51dcd7f4e846f4537e81fa86c27940244fdea9ed Mon Sep 17 00:00:00 2001
From: daa <andrey.dubravin@gmail.com>
Date: Sat, 18 Mar 2017 01:18:41 +0300
Subject: [PATCH] Repaint event on given area

---
 src/nvim.rs     | 14 ++++++++++----
 src/settings.rs |  5 ++++-
 src/shell.rs    | 26 ++++++++++++++++++++++----
 src/ui_model.rs |  6 ++++++
 4 files changed, 42 insertions(+), 9 deletions(-)

diff --git a/src/nvim.rs b/src/nvim.rs
index 4ad463c..0305d88 100644
--- a/src/nvim.rs
+++ b/src/nvim.rs
@@ -1,7 +1,7 @@
 use neovim_lib::{Neovim, NeovimApi, Session, Value, Integer, UiAttachOptions, CallError};
 use std::io::{Result, Error, ErrorKind};
 use std::result;
-use ui_model::UiModel;
+use ui_model::{UiModel, ModelRect};
 use ui;
 use shell::Shell;
 use glib;
@@ -15,7 +15,7 @@ pub trait RedrawEvents {
 
     fn on_resize(&mut self, columns: u64, rows: u64);
 
-    fn on_redraw(&self);
+    fn on_redraw(&self, mode: &RepaintMode);
 
     fn on_highlight_set(&mut self, attrs: &Vec<(Value, Value)>);
 
@@ -114,7 +114,7 @@ fn nvim_cb(method: &str, params: Vec<Value>) {
                     }
                 }
 
-                ui.on_redraw();
+                ui.on_redraw(&RepaintMode::All);
                 Ok(())
             });
         }
@@ -124,7 +124,7 @@ fn nvim_cb(method: &str, params: Vec<Value>) {
                     let args = params.iter().skip(1).cloned().collect();
                     safe_call(move |ui| {
                         call_gui_event(ui, &ev_name, &args)?;
-                        ui.on_redraw();
+                        ui.on_redraw(&RepaintMode::All);
                         Ok(())
                     });
                 } else {
@@ -204,3 +204,9 @@ impl<T> ErrorReport for result::Result<T, CallError> {
         }
     }
 }
+
+pub enum RepaintMode {
+    All,
+    Area(ModelRect),
+}
+
diff --git a/src/settings.rs b/src/settings.rs
index 4da9491..860aec8 100644
--- a/src/settings.rs
+++ b/src/settings.rs
@@ -1,6 +1,9 @@
 #[cfg(unix)]
 use ui::{UI, SET};
 
+#[cfg(unix)]
+use nvim::RepaintMode;
+
 #[cfg(unix)]
 use nvim::RedrawEvents;
 
@@ -77,7 +80,7 @@ fn monospace_font_changed() {
             // rpc is priority for font
             if set.font_source != FontSource::Rpc {
                 set.update_font(&mut ui.shell);
-                ui.shell.on_redraw();
+                ui.shell.on_redraw(&RepaintMode::All);
             }
         });
     });
diff --git a/src/shell.rs b/src/shell.rs
index b8242ed..eea40c3 100644
--- a/src/shell.rs
+++ b/src/shell.rs
@@ -14,19 +14,25 @@ use neovim_lib::{Neovim, NeovimApi, Value, Integer};
 
 use settings;
 use ui_model::{UiModel, Cell, Attrs, Color, COLOR_BLACK, COLOR_WHITE, COLOR_RED};
-use nvim::{RedrawEvents, GuiApi};
+use nvim::{RedrawEvents, GuiApi, RepaintMode};
 use input::{convert_key, keyval_to_input_string};
 use ui::{UI, Ui, SET};
 
 const DEFAULT_FONT_NAME: &'static str = "DejaVu Sans Mono 12";
 
 macro_rules! SHELL {
+    (&$id:ident = $expr:expr) => (
+        UI.with(|ui_cell| {
+        let $id = &ui_cell.borrow().shell;
+        $expr
+    });
+    );
     ($id:ident = $expr:expr) => (
         UI.with(|ui_cell| {
         let mut $id = &mut ui_cell.borrow_mut().shell;
         $expr
     });
-    )
+    );
 }
 
 #[derive(PartialEq)]
@@ -473,8 +479,20 @@ impl RedrawEvents for Shell {
         self.model = UiModel::new(rows, columns);
     }
 
-    fn on_redraw(&self) {
-        self.drawing_area.queue_draw();
+    fn on_redraw(&self, mode: &RepaintMode) {
+        match mode {
+            &RepaintMode::All => self.drawing_area.queue_draw(),
+            &RepaintMode::Area(ref rect) => {
+                SHELL!(&shell = {
+                    if let Some(line_height) = shell.line_height {
+                        if let Some(char_width) = shell.char_width {
+                            let (x, y, width, height) = rect.to_area(line_height as i32, char_width as i32);
+                            self.drawing_area.queue_draw_area(x, y, width, height);
+                        }
+                    }
+                });
+            },
+        }
     }
 
     fn on_set_scroll_region(&mut self, top: u64, bot: u64, left: u64, right: u64) {
diff --git a/src/ui_model.rs b/src/ui_model.rs
index 59e1ee6..d77a53d 100644
--- a/src/ui_model.rs
+++ b/src/ui_model.rs
@@ -258,4 +258,10 @@ impl ModelRect {
             rect.right
         };
     }
+
+    pub fn to_area(&self, line_height: i32, char_width: i32) -> (i32, i32, i32, i32) {
+        let y = self.top as i32 * line_height;
+        let x = self.left as i32 * char_width;
+        (x, y, self.right as i32 * char_width - x, self.bot as i32 * line_height - y)
+    }
 }