Java 画布不能画平滑的线条

在javafx画布中进行徒手绘制时，我无法获得动画化的线条。 下面是代码

import javafx.application.*;
import javafx.event.*;
import javafx.scene.*;
import javafx.scene.canvas.*;
import javafx.scene.control.*;
import javafx.scene.input.*;
import javafx.scene.shape.*;
import javafx.stage.*;

public class Test2 extends Application {
  GraphicsContext gc;

  public static void main(String[] args) { launch(args); }

  private class MouseDragged implements EventHandler<MouseEvent> {
      public void handle( MouseEvent e ) {
        gc.lineTo( e.getX(), e.getY() );
        gc.stroke();
      }
  }

  private class MousePressed implements EventHandler<MouseEvent> {
      public void handle( MouseEvent e ) {
        gc.moveTo( e.getX(), e.getY() );
      }
  }

  @Override
  public void start(Stage stage) {
    Canvas canvas = new Canvas(500, 500);
    canvas.setOnMouseDragged( new MouseDragged() );
    canvas.setOnMousePressed( new MousePressed() );

    gc = canvas.getGraphicsContext2D();
    gc.setLineCap( StrokeLineCap.ROUND );
    gc.setLineJoin( StrokeLineJoin.ROUND );
    gc.setLineWidth( 0.1 );

    Group root = new Group(canvas);
    Scene scene = new Scene(root);
    stage.setTitle("Test2");
    stage.setScene(scene);
    stage.show();
  }
}

---

如何为画布中的图形上下文提供渲染点击？

尝试将此效果添加到

GraphicsContext

：

BoxBlur blur = new BoxBlur();
blur.setWidth(1);
blur.setHeight(1);
blur.setIterations(1);
gc.setEffect(blur);

因此（例如）您的

start

方法现在看起来如下：

  @Override
  public void start(Stage stage) {
    Canvas canvas = new Canvas(500, 500);
    canvas.setOnMouseDragged( new MouseDragged() );
    canvas.setOnMousePressed( new MousePressed() );

    gc = canvas.getGraphicsContext2D();
    gc.setLineCap( StrokeLineCap.ROUND );
    gc.setLineJoin( StrokeLineJoin.ROUND );
    gc.setLineWidth( 1 );

    BoxBlur blur = new BoxBlur();
    blur.setWidth(1);
    blur.setHeight(1);
    blur.setIterations(1);
    gc.setEffect(blur);

    Group root = new Group(canvas);
    Scene scene = new Scene(root);
    stage.setTitle("Test2");
    stage.setScene(scene);
    stage.show();
  }

---

它并不完全完美。。。但到目前为止我发现的最好的事情是。

记录针对旧JavaFX问题跟踪链接的功能请求已经失效。可以记录功能请求（我认为），但是如果您在记录之前先在中讨论，您可能会更幸运地实现功能请求。请注意，这里的实际问题可能是多次绘制相同的点，这会使抗锯齿线出现锯齿。参见相关问题：不错的选择。但出于这个目的，我想我会坚持swing一段时间。没有BuffereImage的灵活性，我几乎做不到什么。

  @Override
  public void start(Stage stage) {
    Canvas canvas = new Canvas(500, 500);
    canvas.setOnMouseDragged( new MouseDragged() );
    canvas.setOnMousePressed( new MousePressed() );

    gc = canvas.getGraphicsContext2D();
    gc.setLineCap( StrokeLineCap.ROUND );
    gc.setLineJoin( StrokeLineJoin.ROUND );
    gc.setLineWidth( 1 );

    BoxBlur blur = new BoxBlur();
    blur.setWidth(1);
    blur.setHeight(1);
    blur.setIterations(1);
    gc.setEffect(blur);

    Group root = new Group(canvas);
    Scene scene = new Scene(root);
    stage.setTitle("Test2");
    stage.setScene(scene);
    stage.show();
  }