graphpanel.java

来自「一个一元曲线多项式数值演示例子」· Java 代码 · 共 553 行

package numbercruncher.graphutils;

import java.awt.*;
import java.awt.event.*;

/**
 * The base panel for all graph demo panels.
 */
public abstract class GraphPanel
    extends Panel
    implements DemoPanel {
  public static final Color MAROON = new Color(128, 0, 0);

  /** header panel */
  private HeaderPanel headerPanel;
  /** plot panel */
  private PlotPanel plotPanel = new PlotPanel(this);
  /** control panel */
  private Panel controlPanel = new Panel();
  /** bounds panel */
  private PlotBoundsPanel boundsPanel;

  /** true to set XOR mode */
  private boolean xorMode;
  /** true to draw axes */
  private boolean drawAxes;
  /** true to draw X=Y line */
  private boolean drawXequalsY;

  /** plot properties */
  private PlotProperties plotProps;
  /** plot bounds */
  private float xMin, xMax, yMin, yMax;

  /** label font */
  private Font labelFont = new Font("Dialog", 1, 12);
  /** text font */
  private Font textFont = new Font("Dialog", 0, 12);

  /**
   * Constructor.
   * @param functions the array of plottable functions
   * @param plotProps the plot properties
   * @param xorMode if true, set XOR mode
   * @param drawXequalsY if true, draw the X=Y line
   */
  protected GraphPanel(Plottable functions[], PlotProperties plotProps,
                       boolean xorMode, boolean drawXequalsY) {
    this.plotProps = plotProps;
    this.xorMode = xorMode;
    this.drawXequalsY = drawXequalsY;
    this.drawAxes = true;

    headerPanel = new HeaderPanel(functions, this);
    boundsPanel = new PlotBoundsPanel(this);

    init();
  }

  /**
   * Constructor.
   * @param headerText the text to display in the header panel
   * @param plotProps the plot properties
   * @param drawAxes if true, draw axes
   */
  protected GraphPanel(String headerText, PlotProperties plotProps,
                       boolean drawAxes) {
    this.plotProps = plotProps;
    this.xorMode = false;
    this.drawXequalsY = false;
    this.drawAxes = drawAxes;

    headerPanel = new HeaderPanel(headerText);
    init();
  }

  /**
   * Constructor.
   * @param headerText the text to display in the header panel
   * @param plotProps the plot properties
   */
  protected GraphPanel(String headerText, PlotProperties plotProps) {
    this.plotProps = plotProps;
    this.xorMode = false;
    this.drawXequalsY = false;
    this.drawAxes = true;

    headerPanel = new HeaderPanel(headerText);
    boundsPanel = new PlotBoundsPanel(this);
    init();
  }

  /**
   * Constructor.
   * @param plotProps the plot properties
   */
  protected GraphPanel(PlotProperties plotProps) {
    this.plotProps = plotProps;
    this.xorMode = false;
    this.drawXequalsY = false;
    this.drawAxes = false;

    init();
  }

  /**
   * Initialize the graph panel.
   */
  private void init() {
    if (boundsPanel != null) {
      boundsPanel.setTextFields(plotProps);

      // Control panel.
    }
    controlPanel.setBackground(Color.lightGray);
    controlPanel.setLayout(new BorderLayout(5, 0));
    if (boundsPanel != null) {
      controlPanel.add(boundsPanel,
                       BorderLayout.WEST);

      // Graph panel.
    }
    setLayout(new BorderLayout());
    if (headerPanel != null) {
      add(headerPanel, BorderLayout.NORTH);
    }
    add(plotPanel, BorderLayout.CENTER);
    add(controlPanel, BorderLayout.SOUTH);
  }

  /**
   * Return the label font.
   * @return the font
   */
  protected Font getLabelFont() {
    return labelFont;
  }

  /**
   * Return the text font.
   * @return the font
   */
  protected Font getTextFont() {
    return textFont;
  }

  /**
   * Return the plot properties.
   * @return the plot properties
   */
  protected PlotProperties getPlotProperties() {
    return plotProps;
  }

  /**
   * Set the plot properties.
   * @param plotProps the plot properties
   */
  protected void setPlotProperties(PlotProperties plotProps) {
    this.plotProps = plotProps;
    boundsPanel.setTextFields(plotProps);
  }

  /**
   * Set the header image.
   * @param the header image
   */
  protected void setHeaderImage(Image image) {
    headerPanel.setImage(image);
  }

  /**
   * Set the header label text in the default black color.
   * @param text the header label text
   */
  protected void setHeaderLabel(String text) {
    headerPanel.setLabel(text);
  }

  /**
   * Set the header label text in color.
   * @param text the header label text
   * @param color the color
   */
  protected void setHeaderLabel(String text, Color color) {
    headerPanel.setLabel(text, color);
  }

  /**
   * Set the function to plot.
   * @param function the function to set
   */
  protected void setFunction(Plottable function) {
    setPlotProperties(function.getPlotProperties());
    headerPanel.setFunction(function);
  }

  /**
   * Set the header to display the function.
   * @param function the function to display
   */
  protected void setHeaderDisplay(Plottable function) {
    headerPanel.setFunction(function);
  }

  /**
   * Add a demo's controls to the control panel.
   * @param the demo's control subpanel
   */
  protected void addDemoControls(Panel demoControlPanel) {
    controlPanel.add(demoControlPanel, BorderLayout.CENTER);
  }

  /**
   * Process a user input error.
   * @param message the error message
   */
  protected void processUserError(String message) {
    headerPanel.displayError(message);
    userErrorOccurred();
  }

  //------------------//
  // Plotting methods //
  //------------------//

  /**
   * Clear the contents of the plot panel.
   */
  public void clear() {
    // Get the plot bounds.
    if (boundsPanel != null) {
      boundsPanel.updatePlotProperties(plotProps);
    }

    // Draw the axes.
    plotPanel.initPlot(plotProps);
    if (drawAxes) {
      plotPanel.drawAxes();
    }
    if (drawXequalsY) {
      plotPanel.drawXequalsY();
    }
  }

  /**
   * Plot a function.
   */
  protected void plotFunction() {
    startPlot(Color.blue);

    // Plot properties.
    int w = plotProps.getWidth();
    float xMin = plotProps.getXMin();
    float deltaX = plotProps.getXDelta();

    // Loop over each pixel of the x axis to plot the function value.
    for (int c = 0; c < w; ++c) {
      float x = xMin + c * deltaX;
      float y = valueAt(x);

      plot(c, y);
    }

    endPlot();
  }

  /**
   * Plot the function.
   * @param function the function to plot
   */
  protected void plotFunction(Plottable plotFunction, Color color) {
    startPlot(color);

    // Plot properties.
    int w = plotProps.getWidth();
    float xMin = plotProps.getXMin();
    float deltaX = plotProps.getXDelta();

    // Loop over each pixel of the x axis to plot the function value.
    for (int c = 0; c < w; ++c) {
      float x = xMin + c * deltaX;
      float y = plotFunction.at(x);

      plot(c, y);
    }

    endPlot();
  }

  /**
   * Return whether or not it is OK to plot the function.
   * @return true or false
   */
  protected boolean plotOK() {
    return true;
  }

  /**
   * Check to make sure the function is in bounds over the interval [a, b].
   * @param a the lower bound
   * @param b the upper bound
   * @throws Exception if it is not
   */
  protected void checkFunctionInBounds(float a, float b) throws Exception {
    // Plot properties.
    int w = plotProps.getWidth();
    float xMin = plotProps.getXMin();
    float yMin = plotProps.getYMin();
    float yMax = plotProps.getYMax();
    float deltaX = plotProps.getXDelta();

    int ca = Math.round( (a - xMin) / deltaX);
    int cb = Math.round( (b - xMin) / deltaX);

    // Loop over each pixel of the x axis to check the function value.
    for (int c = ca; c < cb; ++c) {
      float x = xMin + c * deltaX;
      float y = valueAt(x);

      if ( (y < yMin) || (y > yMax)) {
        throw new Exception("Function out of bounds over the " +
                            "interval [" + a + ", " + b + "]");
      }
    }
  }

  /**
   * Return the value of the plottable function at x.  (Return 0 here.)
   * @param x the value of x
   * @return the value of the function
   */
  protected float valueAt(float x) {
    return 0;
  }

  /**
   * Start a function plot.
   * @param color the plot color
   */
  protected void startPlot(Color color) {
    plotPanel.startPlot(color);
  }

  /**
   * Plot a function point at column c.
   * @param c the column
   * @param y the function value
   */
  protected void plot(int c, float y) {
    plotPanel.plot(c, y);
  }

  /**
   * End a function plot.
   */
  protected void endPlot() {
    plotPanel.endPlot();
  }

  /**
   * Plot a point.
   * @param x the x-coordinate of the point
   * @param y the y-coordinate of the point
   * @param color the point color
   */
  protected void plotPoint(int x, int y, Color color) {
    plotPanel.plotPoint(x, y, color);
  }

  /**
   * Plot a line.
   * @param x1 the x-coordinate of one end of the line
   * @param y1 the y-coordinate of one end of the line
   * @param x2 the x-coordinate of the other end of the line
   * @param y2 the y-coordinate of the other end of the line
   * @param color the line color
   */
  protected void plotLine(int x1, int y1, int x2, int y2, Color color) {
    plotPanel.plotLine(x1, y1, x2, y2, color);
  }

  /**
   * Plot multiple lines.
   * @param xs1 the array of x-coordinates of one end of the lines
   * @param ys1 the array of y-coordinates of one end of the lines
   * @param xs2 the array of x-coordinates of the other end of the lines
   * @param ys2 the array of y-coordinates of the other end of the lines
   * @param color the color of the lines
   */
  protected void plotLines(int xs1[], int ys1[], int xs2[], int ys2[],
                           int k, Color color) {
    plotPanel.plotLines(xs1, ys1, xs2, ys2, k, color);
  }

  /**
   * Plot a rectangle.
   * @param x the x-coordinate of the upper left corner
   * @param y the y-coordinate of the upper left corner
   * @param w the width
   * @param h the height
   * @param color the rectangle color
   */
  protected void plotRectangle(int x, int y, int w, int h, Color color) {
    plotPanel.plotRectangle(x, y, w, h, color);
  }

  /**
   * Plot a dot.
   * @param x the x-coordinate of the dot center
   * @param y the y-coordinate of the dot center
   * @param w the dot width
   * @param color the dot color
   */
  protected void plotDot(int x, int y, int w, Color color) {
    plotPanel.plotDot(x, y, w, color);
  }

  /**
   * Plot multiple dots.
   * @param data the array of dot coordinates
   * @param k the number of dots
   * @param w the width
   * @param color the dot color
   */
  protected void plotDots(Point data[], int k, int w, Color color) {
    plotPanel.plotDots(data, k, w, color);
  }

  protected void fillPolygon(int xs[], int ys[], int k, Color color) {
    plotPanel.fillPolygon(xs, ys, k, color);
  }

  /**
   * Draw the plot.
   */
  protected void drawPlot() {
    plotPanel.drawPlot();
  }

  /**
   * @return the plot panel size
   */
  protected Dimension getPlotPanelSize() {
    return plotPanel.getSize();
  }

  /**
   * Set paint mode.
   */
  protected void setPaintMode() {
    plotPanel.setPainMode();
  }

  /**
   * Set XOR mode.
   */
  protected void setXORMode() {
    plotPanel.setXORMode();
  }

  //--------------------------//
  // DemoPanel implementation //
  //--------------------------//

  /**
   * Initialize the demo.  (Callback from applet.  Do nothing here.)
   */
  public void initializeDemo() {}

  /**
   * Close down the demo.  (Callback from applet.  Do nothing here.)
   */
  public void closeDemo() {}

  /**
   * Draw the contents of the plot panel.
   */
  public void draw() {
    clear();
    if (plotOK()) {
      plotFunction();

      // Set XOR paint mode if desired.
    }
    if (xorMode) {
      plotPanel.setXORMode();
    }
  }

  /**
   * Notification that the panel was resized.  (Callback from DemoFrame.)
   */
  public void panelResized() {
    draw();
  }

  //----------------//
  // Event handlers //
  //----------------//

  /**
   * Do the header action.
   * (Callback from the header panel.  Do nothing here.)
   */
  public void doHeaderAction() {}

  /**
   * Mouse clicked event handler.
   * (Callback from the plot panel.  Do nothing here.)
   * @param ev the mouse event
   */
  public void mouseClickedOnPlot(MouseEvent ev) {}

  /**
   * Mouse pressed event handler.
   * (Callback from the plot panel.  Do nothing here.)
   * @param ev the mouse event
   */
  public void mousePressedOnPlot(MouseEvent ev) {}

  /**
   * Mouse released event handler.
   * (Callback from the plot panel.  Do nothing here.)
   * @param ev the mouse event
   */
  public void mouseReleasedOnPlot(MouseEvent ev) {}

  /**
   * Mouse dragged event handler.
   * (Callback from the plot panel.  Do nothing here.)
   * @param ev the mouse event
   */
  public void mouseDraggedOnPlot(MouseEvent ev) {}

  /**
   * Choose a function.
   * (Callback from the function frame.  Do nothing here.)
   */
  public void chooseFunction(int index) {}

  /**
   * Notification that the plot bounds changed.
   * (Callback from the plot bounds panel.  Do nothing here.)
   */
  public void plotBoundsChanged() {}

  /**
   * Notification that a user input error occurred.  (Do nothing here.)
   */
  protected void userErrorOccurred() {}
}