feat: 实现喷枪功能

src/paint.rs

@@ -1,6 +1,7 @@
 use ::image::{ImageBuffer, ImageError, Rgba};
 use iced::Theme;
 use iced::padding;
+use iced::time::{self, Instant, milliseconds};
 use iced::widget::container;
 use iced::widget::{Column, button, column, image, pick_list, row, text};
 use iced::{Border, Color, Element, Length, Point, Renderer, Task};
@@ -67,9 +68,11 @@ enum Message {
 
     /// 全局鼠标释放
     WindowMouseRelease,
+
+    Tick(Instant),
 }
 
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
 enum Tool {
     FreeFormSelect,
     Select,
@@ -143,12 +146,16 @@ impl From<Tool> for usize {
 pub enum ConfigOption {
     EraserWidth,
     LineWidth,
+    AirbrushRadius,
+    AirbrushDensity,
 }
 
 #[derive(Debug, Clone, Copy)]
 struct Config {
     eraser_width: i32,
     line_width: i32,
+    airbrush_radius: i32,
+    airbrush_density: i32,
 }
 
 impl Default for Config {
@@ -161,6 +168,8 @@ impl Config {
     const DEFAULT: Config = Config {
         line_width: 1,
         eraser_width: 4,
+        airbrush_radius: 4,
+        airbrush_density: 16,
     };
     fn incr(&mut self, option: ConfigOption, step: i32) {
         match option {
@@ -176,6 +185,18 @@ impl Config {
                     self.line_width = Self::DEFAULT.line_width;
                 }
             }
+            ConfigOption::AirbrushRadius => {
+                self.airbrush_radius += step;
+                if self.airbrush_radius < Self::DEFAULT.airbrush_radius {
+                    self.airbrush_radius = Self::DEFAULT.airbrush_radius;
+                }
+            }
+            ConfigOption::AirbrushDensity => {
+                self.airbrush_density += step;
+                if self.airbrush_density < Self::DEFAULT.airbrush_density {
+                    self.airbrush_density = Self::DEFAULT.airbrush_density;
+                }
+            }
         }
     }
 }
@@ -297,27 +318,47 @@ impl PaintApp {
 
         let mut debug_area = row![
             column![
-                text("Eraser Width "),
+                text("Eraser Width"),
                 row![
                     button("+").on_press(Message::Increment(ConfigOption::EraserWidth)),
                     text(self.config.eraser_width).size(20).center(),
                     button("-").on_press(Message::Decrement(ConfigOption::EraserWidth)),
                 ],
-            ],
+            ]
+            .padding(padding::right(5)),
             column![
-                text("Line Width "),
+                text("Line Width"),
                 row![
                     button("+").on_press(Message::Increment(ConfigOption::LineWidth)),
                     text(self.config.line_width).size(20).center(),
                     button("-").on_press(Message::Decrement(ConfigOption::LineWidth)),
                 ],
-            ],
+            ]
+            .padding(padding::right(5)),
             pick_list(
                 &BrushKind::ALL[..],
                 self.brush_selected,
                 Message::BrushSelected,
             )
             .placeholder("Brush..."),
+            column![
+                text("Airbrush Radius"),
+                row![
+                    button("+").on_press(Message::Increment(ConfigOption::AirbrushRadius)),
+                    text(self.config.airbrush_radius).size(20).center(),
+                    button("-").on_press(Message::Decrement(ConfigOption::AirbrushRadius)),
+                ],
+            ]
+            .padding(padding::right(5)),
+            column![
+                text("Airbrush Density"),
+                row![
+                    button("+").on_press(Message::Increment(ConfigOption::AirbrushDensity)),
+                    text(self.config.airbrush_density).size(20).center(),
+                    button("-").on_press(Message::Decrement(ConfigOption::AirbrushDensity)),
+                ],
+            ]
+            .padding(padding::right(5)),
         ];
         debug_area = debug_area.padding(padding::top(10).left(5).bottom(10));
 
@@ -345,6 +386,9 @@ impl PaintApp {
             Tool::Brush => {
                 self.update_with_brush(message);
             }
+            Tool::Airbrush => {
+                self.update_with_airbrush(message);
+            }
             Tool::Line => {
                 self.update_with_line(message);
             }
@@ -394,6 +438,16 @@ impl PaintApp {
                 // 处理鼠标在 canvas_area 外面释放
                 self.is_drawing = false;
             }
+            Message::Tick(_) => {
+                if self.is_drawing && self.tool_selected == Tool::Airbrush {
+                    self.canvas.spray_paint(
+                        self.begin_point,
+                        self.config.airbrush_radius,
+                        self.config.airbrush_density as u32,
+                    );
+                    self.dirty = true;
+                }
+            }
             _ => {}
         }
 
@@ -409,13 +463,15 @@ impl PaintApp {
     }
 
     pub fn subscription(&self) -> Subscription<Message> {
-        event::listen().filter_map(|event| match event {
+        let ev = event::listen().filter_map(|event| match event {
             // 只关心鼠标释放事件
             iced::Event::Mouse(mouse::Event::ButtonReleased(mouse::Button::Left)) => {
                 Some(Message::WindowMouseRelease)
             }
             _ => None,
-        })
+        });
+        let tick = time::every(milliseconds(50)).map(Message::Tick);
+        return Subscription::batch(vec![ev, tick]);
     }
 
     // endregion
@@ -468,6 +524,7 @@ impl PaintApp {
                 self.is_drawing = true;
                 self.canvas.draw_pixel_at(pos);
                 self.begin_point = pos;
+                self.dirty = true;
             }
             Message::MouseReleased(pos) => {
                 self.is_drawing = false;
@@ -516,6 +573,37 @@ impl PaintApp {
         }
     }
 
+    pub fn update_with_airbrush(&mut self, message: Message) {
+        match message {
+            Message::MousePressed(pos) => {
+                self.is_drawing = true;
+                self.canvas.spray_paint(
+                    pos,
+                    self.config.airbrush_radius,
+                    self.config.airbrush_density as u32,
+                );
+                self.begin_point = pos;
+                self.dirty = true;
+            }
+            Message::MouseReleased(pos) => {
+                self.is_drawing = false;
+                self.begin_point = pos;
+            }
+            Message::MouseMoved(pos) => {
+                if self.is_drawing {
+                    self.canvas.spray_paint(
+                        pos,
+                        self.config.airbrush_radius,
+                        self.config.airbrush_density as u32,
+                    );
+                    self.begin_point = pos;
+                    self.dirty = true;
+                }
+            }
+            _ => {}
+        }
+    }
+
     pub fn update_with_line(&mut self, message: Message) {
         match message {
             Message::MousePressed(pos) => {