2 files changed, 31 insertions, 5 deletions

diff --git a/src/app.rs b/src/app.rs
index 059635a..9a1155e 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -1,7 +1,7 @@
 use crate::{
     bitmap::{MapPoint, Pixmap},
     consts::colors::*,
-    rect,
+    dither, rect,
     symmetry::Symmetry,
     undo::{ModifyRecord, OpKind, Operation, UndoStack},
     utils::draw_text,
@@ -24,6 +24,7 @@ use sdl2::{
 pub struct AppState<'ctx> {
     active_color: bool,
     brush_size: u8,
+    dither_level: u8,
     canvas: Canvas<Window>,
     context: &'ctx Sdl,
     ttf_context: &'ctx Sdl2TtfContext,
@@ -130,13 +131,18 @@ impl<'ctx> AppState<'ctx> {
     ) -> Result<Vec<ModifyRecord>, ()> {
         let radius = self.brush_size as u32;
         let center = self.idx_at_coord(center).ok_or(())?;
+        let dither_level = self.dither_level;
 
         let circle = self.pixmap.get_circle(center, radius, true);
         let sym_circle = self.symmetry.apply(&circle);
 
         let mut modify_record = vec![];
 
-        for point in circle.into_iter().chain(sym_circle) {
+        for point in circle
+            .into_iter()
+            .chain(sym_circle)
+            .filter(|&pt| dither::bayer(dither_level, pt))
+        {
             let old_val = self.pixmap.set(point, val);
             modify_record.push(ModifyRecord::new(point, old_val, val));
         }
@@ -151,6 +157,7 @@ impl<'ctx> AppState<'ctx> {
     ) -> Result<Vec<ModifyRecord>, ()> {
         let start = self.idx_at_coord(start).ok_or(())?;
         let end = self.idx_at_coord(end).ok_or(())?;
+        let dither_level = self.dither_level;
 
         let line = self.pixmap.get_line(start, end);
         let sym_line = self.symmetry.apply(&line);
@@ -158,7 +165,10 @@ impl<'ctx> AppState<'ctx> {
         let mut line_modify_record = vec![];
         for point in line.into_iter().chain(sym_line) {
             let circle_around_point = self.pixmap.get_circle(point, self.brush_size as u32, true);
-            for c in circle_around_point {
+            for c in circle_around_point
+                .into_iter()
+                .filter(|&pt| dither::bayer(dither_level, pt))
+            {
                 let old_val = self.pixmap.set(c, val);
                 line_modify_record.push(ModifyRecord::new(c, old_val, val));
             }
@@ -215,6 +225,18 @@ impl<'ctx> AppState<'ctx> {
         }
     }
 
+    fn reduce_intensity(&mut self) {
+        if self.dither_level > 0 {
+            self.dither_level -= 1;
+        }
+    }
+
+    fn increase_intensity(&mut self) {
+        if self.dither_level < 16 {
+            self.dither_level += 1;
+        }
+    }
+
     fn zoom_out(&mut self, p: (i32, i32)) {
         if self.zoom > 1 {
             // attempt to center around cursor
@@ -290,7 +312,7 @@ impl<'ctx> AppState<'ctx> {
         if let Some(center) = pt {
             let circle = self.pixmap.get_circle(center, brush_size as u32, false);
             for MapPoint { x, y } in circle.into_iter() {
-                self.canvas.set_draw_color(GREY);
+                self.canvas.set_draw_color(PINK);
                 self.canvas
                     .fill_rect(Rect::new(
                         x as i32 * cs as i32 + self.start.x(),
@@ -383,6 +405,7 @@ impl<'ctx> AppState<'ctx> {
         Self {
             active_color: true,
             brush_size: 0,
+            dither_level: 16,
             canvas,
             context,
             ttf_context,
@@ -431,6 +454,8 @@ impl<'ctx> AppState<'ctx> {
                             // brush ops
                             Keycode::Q => self.decrease_brush_size(),
                             Keycode::E => self.increase_brush_size(),
+                            Keycode::Num1 => self.reduce_intensity(),
+                            Keycode::Num3 => self.increase_intensity(),
                             // flip color
                             Keycode::X => self.change_active_color(),
                             // toggle grid
diff --git a/src/main.rs b/src/main.rs
index c9c1bdd..14f4cf5 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,6 +1,7 @@
 mod app;
 mod bitmap;
 mod consts;
+mod dither;
 mod symmetry;
 mod undo;
 mod utils;
@@ -10,5 +11,5 @@ use app::AppState;
 pub fn main() {
     let sdl_context = sdl2::init().unwrap();
     let ttf_context = sdl2::ttf::init().unwrap();
-    AppState::init(160, 160, &sdl_context, &ttf_context).run();
+    AppState::init(200, 200, &sdl_context, &ttf_context).run();
 }