feat: Implement crush and save to png

Cargo.lock

@@ -1953,6 +1953,7 @@ version = "0.1.0"
 dependencies = [
  "iced",
  "iced_core",
+ "image",
 ]
 
 [[package]]

Cargo.toml

@@ -6,3 +6,4 @@ edition = "2024"
 [dependencies]
 iced = {version =  "0.14.0",  features = ["advanced", "image"]}
 iced_core = "0.14.0"
+image = "0.25.9"

src/mscanvas.rs

@@ -83,6 +83,44 @@ impl MSCanvas {
         self.pixels.clone()
     }
 
+    pub fn get_pixels_scale(&self, scale: i32) -> Vec<u8> {
+        if scale <= 1 {
+            return self.pixels.clone();
+        }
+        let dst_width = self.width * scale;
+        let dst_height = self.width * scale;
+        let mut dst = vec![0; (self.width * self.width * 4) as usize]; // RGBA
+
+        for y in 0..self.height {
+            for x in 0..self.width {
+                // 源像素索引
+                let src_idx = ((y * self.width + x) * 4) as usize;
+
+                // 源像素颜色
+                let r = self.pixels[src_idx];
+                let g = self.pixels[src_idx + 1];
+                let b = self.pixels[src_idx + 2];
+                let a = self.pixels[src_idx + 3];
+
+                // 在目标图像中填充 scale×scale 区域
+                for dy in 0..scale {
+                    for dx in 0..scale {
+                        let dst_x = x * scale + dx;
+                        let dst_y = y * scale + dy;
+                        let dst_idx = ((dst_y * dst_width + dst_x) * 4) as usize;
+
+                        dst[dst_idx] = r;
+                        dst[dst_idx + 1] = g;
+                        dst[dst_idx + 2] = b;
+                        dst[dst_idx + 3] = a;
+                    }
+                }
+            }
+        }
+
+        dst
+    }
+
     pub fn pixel_at(&self, x: i32, y: i32) -> MSColor {
         // 边界检查
         if x < 0 || x >= self.width || y < 0 || y >= self.height as i32 {
@@ -118,6 +156,25 @@ impl MSCanvas {
         self.pixels[index + 3] = self.color.a; // A
     }
 
+    pub fn draw_pixel_color_at(&mut self, point: Point, color: MSColor) {
+        let Point { x, y } = point;
+        let x = x as i32;
+        let y = y as i32;
+        // 边界检查
+        if x < 0 || x >= self.width || y < 0 || y >= self.height {
+            return;
+        }
+        // 计算索引：(y * width + x) * 4
+        let index = ((y * self.width + x) * 4) as usize;
+
+        // 写入 RGBA 数据
+        // 注意：Color 的 r, g, b, a 是 0.0 - 1.0，需要转为 0 - 255
+        self.pixels[index] = color.r; // R
+        self.pixels[index + 1] = color.g; // G
+        self.pixels[index + 2] = color.b; // B
+        self.pixels[index + 3] = color.a; // A
+    }
+
     fn draw_pixel_at1(&mut self, x: i32, y: i32) {
         // 边界检查
         if x < 0 || x >= self.width || y < 0 || y >= self.height {
@@ -160,6 +217,17 @@ impl MSCanvas {
         }
     }
 
+    pub fn draw_cross_color(&mut self, point: Point, color: MSColor) {
+        let Point { x, y } = point;
+        let r = 5;
+        for dy in -r..=r {
+            self.draw_pixel_color_at(Point::new(point.x, point.y + dy as f32), color);
+        }
+        for dx in -r..=r {
+            self.draw_pixel_color_at(Point::new(point.x + dx as f32, point.y), color);
+        }
+    }
+
     pub fn brush_circle(&mut self, center: Point) {
         if self.line_width <= 1 {
             self.draw_pixel_at(center);
@@ -191,6 +259,27 @@ impl MSCanvas {
         }
     }
 
+    pub fn brush_slash(&mut self, center: Point) {
+        let r = self.line_width / 2;
+        let l = self.line_width - r;
+        // for dx in -1..1 {
+        //     for d in -l..r {
+        //         self.draw_pixel_at(Point::new(center.x - (d as f32) + (dx as f32), center.y - d as f32));
+        //     }
+        // }
+        for d in -l..r {
+            self.draw_pixel_at(Point::new(center.x - (d as f32), center.y - d as f32));
+        }
+    }
+
+    pub fn brush_backslash(&mut self, center: Point) {
+        let r = self.line_width / 2;
+        let l = self.line_width - r;
+        for d in -l..r {
+            self.draw_pixel_at(Point::new(center.x + d as f32, center.y - d as f32));
+        }
+    }
+
     fn bresenham_line(&mut self, begin: Point, end: Point) -> Vec<Point> {
         let x1 = begin.x;
         let y1 = begin.y;
@@ -433,6 +522,10 @@ impl MSCanvas {
     }
 
     pub fn stroke_rect(&mut self, x: i32, y: i32, width: i32, height: i32) {
+        if width < 2 * self.line_width || height < 2 * self.line_width {
+            self.fill_rect(x, y, width, height);
+            return;
+        }
         self.fill_rect(x, y, width, self.line_width);
         self.fill_rect(x, y + height - self.line_width, width, self.line_width);
         self.fill_rect(x, y, self.line_width, height);
@@ -440,6 +533,7 @@ impl MSCanvas {
     }
 
     pub fn stroke_rect1(&mut self, p1: Point, p2: Point) {
+        self.draw_cross_color(p1, MSColor::new(255, 0, 0, 255));
         let mut x = p1.x;
         let mut y = p1.y;
         let mut width = (p2.x - p1.x);

src/paint.rs

@@ -1,5 +1,4 @@
-use crate::image_button::image_button;
+use ::image::RgbaImage;
-use crate::mouse_area::mouse_area;
 use iced::Theme;
 use iced::padding;
 use iced::widget::container;
@@ -7,6 +6,8 @@ use iced::widget::{Column, button, column, image, pick_list, row, text};
 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;
 use crate::mscanvas::MSCanvas;
 
 const WIDTH: u32 = 800;
@@ -50,7 +51,9 @@ enum Message {
     MousePressed(Point),
     MouseReleased(Point),
     MouseMoved(Point),
+
     Clear,
+    SavePNG,
     // 内部消息：请求刷新图像
     RefreshImage,
 
@@ -233,7 +236,7 @@ impl PaintApp {
         let canvas_area = container(canvas_area)
             .width(Length::Fill)
             .height(Length::Fill)
-            .padding(padding::left(5).top(5))
+            .padding(padding::left(5).top(5).right(5))
             .style(|_| container::Style {
                 background: Some(color!(0x808080).into()),
                 ..container::Style::default()
@@ -288,19 +291,23 @@ impl PaintApp {
                 }
             });
 
-        let mut debug_area = column![
+        let mut debug_area = row![
+            column![
                 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)),
                 ],
+            ],
+            column![
                 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)),
                 ],
+            ],
             pick_list(
                 &BrushKind::ALL[..],
                 self.brush_selected,
@@ -308,11 +315,15 @@ impl PaintApp {
             )
             .placeholder("Brush..."),
         ];
-        debug_area = debug_area.padding(padding::left(5).right(5));
+        debug_area = debug_area.padding(padding::top(10).left(5).bottom(10));
 
         column![
+            row![
                 button("CLEAR").on_press(Message::Clear),
-            row![tool_area, canvas_area, debug_area],
+                button("PNG").on_press(Message::SavePNG),
+            ],
+            row![tool_area, canvas_area],
+            debug_area,
         ]
     }
 
@@ -327,6 +338,9 @@ impl PaintApp {
             Tool::Pencil => {
                 self.update_with_pencil(message);
             }
+            Tool::Brush => {
+                self.update_with_brush(message);
+            }
             Tool::Line => {
                 self.update_with_line(message);
             }
@@ -342,6 +356,18 @@ impl PaintApp {
                 self.canvas.clear();
                 self.dirty = true;
             }
+            Message::SavePNG => {
+                let scale = 4;
+                let (width, height) = self.canvas.size();
+                let pixels = self.canvas.get_pixels_scale(4);
+                save_rgba_as_png(
+                    pixels,
+                    (width * scale) as u32,
+                    (height * scale) as u32,
+                    "mspaint.png",
+                )
+                .unwrap();
+            }
             Message::RefreshImage => {
                 if self.dirty {
                     self.update_image_handle();
@@ -358,11 +384,14 @@ impl PaintApp {
                 }
             }
             Message::Decrement(opt) => {
-                self.config.incr(opt, 1);
+                self.config.incr(opt, -1);
                 if opt == ConfigOption::LineWidth {
                     self.canvas.set_line_width(self.config.line_width);
                 }
             }
+            Message::BrushSelected(kind) => {
+                self.brush_selected = Some(kind);
+            }
             _ => {}
         }
 
@@ -443,6 +472,38 @@ impl PaintApp {
         }
     }
 
+    pub fn update_with_brush(&mut self, message: Message) {
+        let mut brush_fn: fn(&mut MSCanvas, Point) = MSCanvas::brush_circle;
+        if let Some(kind) = self.brush_selected {
+            brush_fn = match kind {
+                BrushKind::Circle => MSCanvas::brush_circle,
+                BrushKind::Square => MSCanvas::brush_square,
+                BrushKind::Slash => MSCanvas::brush_slash,
+                BrushKind::Backslash => MSCanvas::brush_backslash,
+            }
+        }
+        match message {
+            Message::MousePressed(pos) => {
+                self.is_drawing = true;
+                brush_fn(&mut self.canvas, pos);
+                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.draw_line_with(self.begin_point, pos, brush_fn);
+                    self.begin_point = pos;
+                    self.dirty = true;
+                }
+            }
+            _ => {}
+        }
+    }
+
     pub fn update_with_line(&mut self, message: Message) {
         match message {
             Message::MousePressed(pos) => {
@@ -520,3 +581,24 @@ pub fn main() -> iced::Result {
         .theme(Theme::Dark)
         .run()
 }
+
+fn save_rgba_as_png(
+    pixels: Vec<u8>,
+    width: u32,
+    height: u32,
+    path: &str,
+) -> Result<(), Box<dyn std::error::Error>> {
+    // 验证像素数量是否匹配
+    if pixels.len() != (width * height * 4) as usize {
+        return Err("Pixel buffer size does not match width × height × 4".into());
+    }
+
+    // 创建 RgbaImage
+    let img: RgbaImage = RgbaImage::from_vec(width, height, pixels)
+        .ok_or("Failed to create image from pixel data")?;
+
+    // 保存为 PNG（保留 Alpha 通道）
+    img.save(path)?;
+
+    Ok(())
+}