feat: Implement rectangle

src/paint.rs

@@ -1,11 +1,11 @@
+use crate::image_button::image_button;
+use crate::mouse_area::mouse_area;
 use iced::Theme;
 use iced::padding;
 use iced::widget::container;
 use iced::widget::{Column, button, column, image, row};
-use iced::{Border, Color, Length, Point, Task, Element, Renderer};
+use iced::{Border, Color, Element, Length, Point, Renderer, Task};
 use iced_core::color;
-use crate::image_button::image_button;
-use crate::mouse_area::mouse_area;
 
 const WIDTH: u32 = 800;
 const HEIGHT: u32 = 600;
@@ -113,7 +113,12 @@ impl ColorU8 {
     }
 }
 
-struct Paint {
+
+pub fn point_to_i32(point: Point) -> Point<i32> {
+    Point::new(point.x as i32, point.y as i32)
+}
+
+struct PaintApp {
     tool_states: [bool; Tool::Count as usize],
     tool_selected: Tool,
 
@@ -141,7 +146,7 @@ struct Paint {
     dirty: bool,
 }
 
-impl Paint {
+impl PaintApp {
     // region iced application (new view update)
 
     pub fn new() -> Self {
@@ -179,11 +184,9 @@ impl Paint {
             .width(Length::Fill)
             .height(Length::Fill)
             .padding(padding::left(5).top(5))
-            .style(|_| {
+            .style(|_| container::Style {
-                container::Style {
                 background: Some(color!(0x808080).into()),
                 ..container::Style::default()
-                }
             });
 
         let mut columns: Vec<Element<'_, Message, Theme, Renderer>> = Vec::new();
@@ -197,7 +200,7 @@ impl Paint {
             let btn2 = image_button(
                 format!("image/normal/normal_{:02}.jpg", i + 2),
                 format!("image/selected/selected_{:02}.jpg", i + 2),
-                self.tool_states[i+1],
+                self.tool_states[i + 1],
             )
             .on_press(Message::ClickTool(Tool::from(i + 1)));
             columns.push(row![btn1, btn2].into());
@@ -253,6 +256,9 @@ impl Paint {
             Tool::Line => {
                 self.update_with_line(message);
             }
+            Tool::Rectangle => {
+                self.update_with_rectangle(message);
+            }
             _ => {}
         }
 
@@ -301,9 +307,8 @@ impl Paint {
     pub fn update_with_pencil(&mut self, message: Message) {
         match message {
             Message::MousePressed(pos) => {
-                println!("pressed: {:?}", pos);
                 self.is_drawing = true;
-                self.draw_pixel_at1(pos);
+                self.draw_pixel_atp(pos);
                 self.begin_point = pos;
             }
             Message::MouseReleased(pos) => {
@@ -341,6 +346,27 @@ impl Paint {
         }
     }
 
+    pub fn update_with_rectangle(&mut self, message: Message) {
+        match message {
+            Message::MousePressed(pos) => {
+                self.is_drawing = true;
+                self.save_pixels();
+                self.begin_point = pos;
+            }
+            Message::MouseReleased(pos) => {
+                self.is_drawing = false;
+                self.begin_point = pos;
+            }
+            Message::MouseMoved(pos) => {
+                if self.is_drawing {
+                    self.restore_pixels();
+                    self.stroke_rect1(self.begin_point, pos, self.brush_radius * 2);
+                }
+            }
+            _ => {}
+        }
+    }
+
     // endregion
 
     pub fn update_tool_states(&mut self, tool: Tool) {
@@ -368,7 +394,7 @@ impl Paint {
 
 /// draw method
 #[allow(unused)]
-impl Paint {
+impl PaintApp {
     fn pixel_at(&self, x: i32, y: i32) -> ColorU8 {
         // 边界检查
         if x < 0 || x >= WIDTH as i32 || y < 0 || y >= HEIGHT as i32 {
@@ -415,6 +441,7 @@ impl Paint {
         }
     }
 
+    #[inline]
     fn draw_pixel_at_raw(&mut self, x: u32, y: u32) {
         // 计算索引：(y * width + x) * 4
         let index = ((y * WIDTH + x) * 4) as usize;
@@ -429,7 +456,7 @@ impl Paint {
         self.dirty = true;
     }
 
-    /// 核心绘图逻辑：直接在字节数组上操作
+    #[inline]
     fn draw_pixel_at(&mut self, x: i32, y: i32) {
         // 边界检查
         if x < 0 || x >= WIDTH as i32 || y < 0 || y >= HEIGHT as i32 {
@@ -460,36 +487,21 @@ impl Paint {
         self.dirty = true;
     }
 
-    fn draw_pixel_at1(&mut self, pos: Point) {
+    fn draw_pixel_atp(&mut self, pos: Point) {
         self.draw_pixel_at(pos.x as i32, pos.y as i32)
     }
 
-    fn draw_lines(&mut self, points: &[Point]) {
+    fn draw_pixels(&mut self, points: Vec<Point<i32>>) {
-        if points.is_empty() {
+        for point in &points {
-            return;
+            self.draw_pixel_at(point.x, point.y);
-        }
-        if points.len() == 1 {
-            self.draw_pixel_at1(points[0]);
-            return;
-        }
-
-        let mut begin = points[0];
-        for point in points.iter().skip(1) {
-            self.draw_line(begin, point.clone());
-            begin = point.clone();
         }
     }
 
-    /// Bresenham's line drawing algorithm
+    fn bresenham_line(&mut self, begin: Point<i32>, end: Point<i32>) -> Vec<Point<i32>> {
-    fn draw_line(&mut self, begin: Point, end: Point) {
+        let x1 = begin.x ;
-        let x1 = begin.x as i32;
+        let y1 = begin.y;
-        let y1 = begin.y as i32;
+        let x2 = end.x ;
-        let x2 = end.x as i32;
+        let y2 = end.y;
-        let y2 = end.y as i32;
-
-        // draw start end point, 防止多条线段在连接点出现断开（比如 ab bc）
-        self.draw_pixel_at(x1, y1);
-        self.draw_pixel_at(x2, y2);
 
         let dx = (x2 - x1);
         let dy = (y2 - y1);
@@ -503,17 +515,20 @@ impl Paint {
         let xe;
         let ye;
 
+        let mut points = Vec::new();
         if dy1 <= dx1 {
             if dx >= 0 {
                 x = x1;
                 y = y1;
                 xe = x2;
+                ye = y2;
             } else {
                 x = x2;
                 y = y2;
                 xe = x1;
+                ye = y1;
             }
-            self.draw_pixel_at(x, y);
+            points.push(Point::new(x, y));
             while x < xe {
                 x += 1;
                 if px < 0 {
@@ -526,19 +541,21 @@ impl Paint {
                     }
                     px = px + 2 * (dy1 - dx1);
                 }
-                self.draw_pixel_at(x, y);
+                points.push(Point::new(x, y));
             }
         } else {
             if dy >= 0 {
                 x = x1;
                 y = y1;
                 ye = y2;
+                xe = x2;
             } else {
                 x = x2;
                 y = y2;
                 ye = y1;
+                xe = x1;
             }
-            self.draw_pixel_at(x, y);
+            points.push(Point::new(x, y));
             while y < ye {
                 y = y + 1;
                 if py <= 0 {
@@ -551,7 +568,36 @@ impl Paint {
                     }
                     py = py + 2 * (dx1 - dy1);
                 }
-                self.draw_pixel_at(x, y);
+                points.push(Point::new(x, y));
+            }
+        }
+        points.push(Point::new(xe, ye));
+
+        points
+    }
+
+    /// Bresenham's line drawing algorithm
+    fn draw_line(&mut self, begin: Point, end: Point) {
+        let points = self.bresenham_line(point_to_i32(begin), point_to_i32(end));
+        self.draw_pixels(points);
+    }
+
+    fn draw_line_thick(&mut self, begin: Point<i32>, end: Point<i32>, line_width: i32) {
+        if line_width <= 0 {
+            return;
+        }
+
+        let half = (line_width) / 2;
+        let points = self.bresenham_line(begin, end);
+        if line_width == 1 {
+            self.draw_pixels(points);
+            return;
+        }
+        for point in &points {
+            for dx in -half..=(line_width  - 1 - half) {
+                for dy in -half..=(line_width - 1 - half) {
+                    self.draw_pixel_at((point.x + dx), (point.y + dy));
+                }
             }
         }
     }
@@ -727,10 +773,25 @@ impl Paint {
 
         (iter_count, fill_count)
     }
+
+    fn stroke_rect(&mut self, x: i32, y: i32, width: i32, height: i32, line_width: i32) {
+        self.draw_line_thick(Point::new(x, y), Point::new(x, y + height), line_width);
+        self.draw_line_thick(Point::new(x, y + height), Point::new(x + width, y + height), line_width);
+        self.draw_line_thick(Point::new(x + width, y + height), Point::new(x + width, y), line_width);
+        self.draw_line_thick(Point::new(x, y), Point::new(x + width, y), line_width);
+    }
+
+    fn stroke_rect1(&mut self, left_top: Point, right_bottom: Point, line_width: i32) {
+        let x = left_top.x as i32;
+        let y = left_top.y as i32;
+        let width = (right_bottom.x - left_top.x) as i32;
+        let height = (right_bottom.y - left_top.y) as i32;
+        self.stroke_rect(x, y, width, height, line_width);
+    }
 }
 
 pub fn main() -> iced::Result {
-    iced::application(Paint::new, Paint::update, Paint::view)
+    iced::application(PaintApp::new, PaintApp::update, PaintApp::view)
         .theme(Theme::Dark)
         .run()
 }