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Modularized fork of Processing Core libraries.
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/* -*- mode: java; c-basic-offset: 2; indent-tabs-mode: nil -*- */

/*
 * Adapted for libp5x.
 *
 * Changes copyright (c) 2024 Neil C Smith
 */

/*
  Part of the Processing project - http://processing.org

  Copyright (c) 2012-22 The Processing Foundation
  Copyright (c) 2004-12 Ben Fry and Casey Reas
  Copyright (c) 2001-04 Massachusetts Institute of Technology

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation, version 2.1.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General
  Public License along with this library; if not, write to the
  Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  Boston, MA  02111-1307  USA
*/

package processing.core;

import java.io.*;
import java.lang.reflect.*;
import java.net.*;
import java.nio.charset.StandardCharsets;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;
import java.util.zip.*;

// loadXML() error handling
import javax.xml.parsers.ParserConfigurationException;
import org.xml.sax.SAXException;

// TODO have this removed by 4.0 final
import processing.awt.ShimAWT;

import processing.data.*;
import processing.event.*;
import processing.opengl.*;


/**
 * Base class for all sketches that use processing.core.
 * 
 * The 
 * Window Size and Full Screen page on the Wiki has useful information
 * about sizing, multiple displays, full screen, etc.
 * 

 * Processing uses active mode rendering. All animation tasks happen on the
 * "Processing Animation Thread". The setup() and draw() methods are handled
 * by that thread, and events (like mouse movement and key presses, which are
 * fired by the event dispatch thread or EDT) are queued to be safely handled
 * at the end of draw().
 * 

 * Starting with 3.0a6, blit operations are on the EDT, so as not to cause
 * GUI problems with Swing and AWT. In the case of the default renderer, the
 * sketch renders to an offscreen image, then the EDT is asked to bring that
 * image to the screen.
 * 

 * For code that needs to run on the EDT, use EventQueue.invokeLater(). When
 * doing so, be careful to synchronize between that code and the Processing
 * animation thread. That is, you can't call Processing methods from the EDT
 * or at any random time from another thread. Use of a callback function or
 * the registerXxx() methods in PApplet can help ensure that your code doesn't
 * do something naughty.
 * 

 * As of Processing 3.0, we have removed Applet as the base class for PApplet.
 * This means that we can remove lots of legacy code, however one downside is
 * that it's no longer possible (without extra code) to embed a PApplet into
 * another Java application.
 * 

 * As of Processing 3.0, we have discontinued support for versions of Java
 * prior to 1.8. We don't have enough people to support it, and for a
 * project of our (tiny) size, we should be focusing on the future, rather
 * than working around legacy Java code.
 */
@SuppressWarnings({"unused", "FinalStaticMethod", "ManualMinMaxCalculation"})
public class PApplet implements PConstants {
//public class PApplet extends PSketch {  // possible in the next alpha
  /** Full name of the Java version (i.e. 1.5.0_11). */
  static public final String javaVersionName =
    System.getProperty("java.version");

  static public final int javaPlatform;
  static {
    String version = javaVersionName;
    if (javaVersionName.startsWith("1.")) {
      version = version.substring(2);
      javaPlatform = parseInt(version.substring(0, version.indexOf('.')));
    } else {
      // Remove -xxx and .yyy from java.version (@see JEP-223)
      javaPlatform = parseInt(version.replaceAll("-.*","").replaceAll("\\..*",""));
    }
  }

  /**
   * Do not use; javaPlatform or javaVersionName are better options.
   * For instance, javaPlatform is useful when you need a number for
   * comparison, i.e. "if (javaPlatform >= 9)".
   */
  @Deprecated
  public static final float javaVersion = 1 + javaPlatform / 10f;

  /**
   * Current platform in use, one of the PConstants WINDOWS, MACOS, LINUX or OTHER.
   */
  static public int platform;

  static {
    final String name = System.getProperty("os.name");

    if (name.contains("Mac")) {
      platform = MACOS;

    } else if (name.contains("Windows")) {
      platform = WINDOWS;

    } else if (name.equals("Linux")) {  // true for the ibm vm
      platform = LINUX;

    } else {
      platform = OTHER;
    }
  }

  /**
   * Whether to use native (AWT) dialogs for selectInput and selectOutput.
   * The native dialogs on some platforms can be ugly, buggy, or missing
   * features. For 3.3.5, this defaults to true on all platforms.
   */
  static public boolean useNativeSelect = true;

  /** The PGraphics renderer associated with this PApplet */
  public PGraphics g;

  /**
   * System variable that stores the width of the computer screen.
   * For example, if the current screen resolution is 1920x1080,
   * displayWidth is 1920 and displayHeight is 1080.
   *
   * @webref environment
   * @webBrief Variable that stores the width of the computer screen
   * @see PApplet#displayHeight
   * @see PApplet#size(int, int)
   */
  public int displayWidth;

  /**
   * System variable that stores the height of the computer screen.
   * For example, if the current screen resolution is 1920x1080,
   * displayWidth is 1920 and displayHeight is 1080.
   *
   * @webref environment
   * @webBrief Variable that stores the height of the computer screen
   * @see PApplet#displayWidth
   * @see PApplet#size(int, int)
   */
  public int displayHeight;

  public int windowX;
  public int windowY;

  /** A leech graphics object that is echoing all events. */
  public PGraphics recorder;

  /**
   * Command line options passed in from main().
   * This does not include the arguments passed in to PApplet itself.
   * @see PApplet#main
   */
  public String[] args;

  /**
   * Path to sketch folder. Previously undocumented, and made private
   * in 3.0 alpha 5 so that people use the sketchPath() method which
   * will initialize it properly. Call sketchPath() once to set it.
   */
  private String sketchPath;

  static final boolean DEBUG = false;
//  static final boolean DEBUG = true;

  /** Default width and height for sketch when not specified */
  static public final int DEFAULT_WIDTH = 100;
  static public final int DEFAULT_HEIGHT = 100;

  /**
   * The pixels[] array contains the values for all the pixels in the
   * display window. These values are of the color datatype. This array is
   * defined by the size of the display window. For example, if the window is
   * 100 x 100 pixels, there will be 10,000 values and if the window is
   * 200 x 300 pixels, there will be 60,000 values. When the pixel density is
   * set to higher than 1 with the pixelDensity() function, these values
   * will change. See the reference for pixelWidth or pixelHeight
   * for more information.
   * 


   * Before accessing this array, the data must be loaded with the loadPixels()
   * function. Failure to do so may result in a NullPointerException. Subsequent
   * changes to the display window will not be reflected in pixels until
   * loadPixels() is called again. After pixels has been modified,
   * the updatePixels() function must be run to update the content of the
   * display window.
   *
   * @webref image:pixels
   * @webBrief Array containing the values for all the pixels in the display window
   * @see PApplet#loadPixels()
   * @see PApplet#updatePixels()
   * @see PApplet#get(int, int, int, int)
   * @see PApplet#set(int, int, int)
   * @see PImage
   * @see PApplet#pixelDensity(int)
   * @see PApplet#pixelWidth
   * @see PApplet#pixelHeight
   */
  public int[] pixels;

  /**
   *
   * System variable which stores the width of the display window. This value
   * is set by the first parameter of the size() function. For
   * example, the function call size(320, 240) sets the width
   * variable to the value 320. The value of width defaults to 100 if
   * size() is not used in a program.
   *
   * @webref environment
   * @webBrief System variable which stores the width of the display window
   * @see PApplet#height
   * @see PApplet#size(int, int)
   */
  public int width = DEFAULT_WIDTH;

  /**
   *
   * System variable which stores the height of the display window. This
   * value is set by the second parameter of the size() function. For
   * example, the function call size(320, 240) sets the height
   * variable to the value 240. The value of height defaults to 100 if
   * size() is not used in a program.
   *
   * @webref environment
   * @webBrief System variable which stores the height of the display window
   * @see PApplet#width
   * @see PApplet#size(int, int)
   */
  public int height = DEFAULT_HEIGHT;

  /**
   *
   * When pixelDensity(2) is used to make use of a high resolution
   * display (called a Retina display on OS X or high-dpi on Windows and
   * Linux), the width and height of the sketch do not change, but the
   * number of pixels is doubled. As a result, all operations that use pixels
   * (like loadPixels(), get(), set(), etc.) happen
   * in this doubled space. As a convenience, the variables pixelWidth
   * and pixelHeight hold the actual width and height of the sketch
   * in pixels. This is useful for any sketch that uses the pixels[]
   * array, for instance, because the number of elements in the array will
   * be pixelWidth*pixelHeight, not width*height.
   *
   * @webref environment
   * @webBrief The actual pixel width when using high resolution display
   * @see PApplet#pixelHeight
   * @see #pixelDensity(int)
   * @see #displayDensity()
   */
  public int pixelWidth;


  /**
   * When pixelDensity(2) is used to make use of a high resolution
   * display (called a Retina display on OS X or high-dpi on Windows and
   * Linux), the width and height of the sketch do not change, but the
   * number of pixels is doubled. As a result, all operations that use pixels
   * (like loadPixels(), get(), set(), etc.) happen
   * in this doubled space. As a convenience, the variables pixelWidth
   * and pixelHeight hold the actual width and height of the sketch
   * in pixels. This is useful for any sketch that uses the pixels[]
   * array, for instance, because the number of elements in the array will
   * be pixelWidth*pixelHeight, not width*height.
   *
   * @webref environment
   * @webBrief The actual pixel height when using high resolution display
   * @see PApplet#pixelWidth
   * @see #pixelDensity(int)
   * @see #displayDensity()
   */
  public int pixelHeight;

  // Making this private until we have a compelling reason to make it public.
  // Seems problematic/weird for it to be possible to set windowRatio = false
  // relative to how other API works. And not sure what the use case would be.
  private boolean windowRatio;

  /**
   * Version of mouseX/mouseY to use with windowRatio().
   */
  public int rmouseX;
  public int rmouseY;

  /**
   * Version of width/height to use with windowRatio().
   */
  public int rwidth;
  public int rheight;

  /** Offset from left when windowRatio is in use. */
  public float ratioLeft;

  /** Offset from the top when windowRatio is in use. */
  public float ratioTop;

  /** Amount of scaling to be applied for the window ratio. */
  public float ratioScale;

  /**
   * Keeps track of ENABLE_KEY_REPEAT hint
   */
  protected boolean keyRepeatEnabled = false;

  /**
   * The system variable mouseX always contains the current horizontal
   * coordinate of the mouse.
   * 


   * Note that Processing can only track the mouse position when the pointer
   * is over the current window. The default value of mouseX is 0,
   * so 0 will be returned until the mouse moves in front of the sketch
   * window. (This typically happens when a sketch is first run.)  Once the
   * mouse moves away from the window, mouseX will continue to report
   * its most recent position.
   *
   * @webref input:mouse
   * @webBrief The system variable that always contains the current horizontal coordinate of the mouse
   * @see PApplet#mouseY
   * @see PApplet#pmouseX
   * @see PApplet#pmouseY
   * @see PApplet#mousePressed
   * @see PApplet#mousePressed()
   * @see PApplet#mouseReleased()
   * @see PApplet#mouseClicked()
   * @see PApplet#mouseMoved()
   * @see PApplet#mouseDragged()
   * @see PApplet#mouseButton
   * @see PApplet#mouseWheel(MouseEvent)
   */
  public int mouseX;

  /**
   * The system variable mouseY always contains the current
   * vertical coordinate of the mouse.
   * 


   * Note that Processing can only track the mouse position when the pointer
   * is over the current window. The default value of mouseY is 0,
   * so 0 will be returned until the mouse moves in front of the sketch
   * window. (This typically happens when a sketch is first run.)  Once the
   * mouse moves away from the window, mouseY will continue to report
   * its most recent position.
   *
   * @webref input:mouse
   * @webBrief The system variable that always contains the current vertical coordinate of the mouse
   * @see PApplet#mouseX
   * @see PApplet#pmouseX
   * @see PApplet#pmouseY
   * @see PApplet#mousePressed
   * @see PApplet#mousePressed()
   * @see PApplet#mouseReleased()
   * @see PApplet#mouseClicked()
   * @see PApplet#mouseMoved()
   * @see PApplet#mouseDragged()
   * @see PApplet#mouseButton
   * @see PApplet#mouseWheel(MouseEvent)
   *
   */
  public int mouseY;

  /**
   * The system variable pmouseX always contains the horizontal
   * position of the mouse in the frame previous to the current frame.

   * 

   * You may find that pmouseX and pmouseY have different values
   * when referenced inside of draw() and inside of mouse events like
   * mousePressed() and mouseMoved(). Inside draw(),
   * pmouseX and pmouseY update only once per frame (once per trip
   * through the draw() loop). But inside mouse events, they update each
   * time the event is called. If these values weren't updated immediately during
   * events, then the mouse position would be read only once per frame, resulting
   * in slight delays and choppy interaction. If the mouse variables were always
   * updated multiple times per frame, then something like line(pmouseX, pmouseY,
   * mouseX, mouseY) inside draw() would have lots of gaps, because
   * pmouseX may have changed several times in between the calls to
   * line().


   * If you want values relative to the previous frame, use pmouseX and
   * pmouseY inside draw(). If you want continuous response, use
   * pmouseX and pmouseY inside the mouse event functions.
   *
   * @webref input:mouse
   * @webBrief The system variable that always contains the horizontal
   * position of the mouse in the frame previous to the current frame
   * @see PApplet#mouseX
   * @see PApplet#mouseY
   * @see PApplet#pmouseY
   * @see PApplet#mousePressed
   * @see PApplet#mousePressed()
   * @see PApplet#mouseReleased()
   * @see PApplet#mouseClicked()
   * @see PApplet#mouseMoved()
   * @see PApplet#mouseDragged()
   * @see PApplet#mouseButton
   * @see PApplet#mouseWheel(MouseEvent)
   */
  public int pmouseX;

  /**
   * The system variable pmouseY always contains the vertical position
   * of the mouse in the frame previous to the current frame. More detailed
   * information about how pmouseY is updated inside of draw()
   * and mouse events is explained in the reference for pmouseX.
   *
   * @webref input:mouse
   * @webBrief The system variable that always contains the vertical position
   * of the mouse in the frame previous to the current frame
   * @see PApplet#mouseX
   * @see PApplet#mouseY
   * @see PApplet#pmouseX
   * @see PApplet#mousePressed
   * @see PApplet#mousePressed()
   * @see PApplet#mouseReleased()
   * @see PApplet#mouseClicked()
   * @see PApplet#mouseMoved()
   * @see PApplet#mouseDragged()
   * @see PApplet#mouseButton
   * @see PApplet#mouseWheel(MouseEvent)
   */
  public int pmouseY;

  /**
   * Previous mouseX/Y for the draw loop, separated out because this is
   * separate from the pmouseX/Y when inside the mouse event handlers.
   * See emouseX/Y for an explanation.
   */
  protected int dmouseX, dmouseY;

  /**
   * The pmouseX/Y for the event handlers (mousePressed(), mouseDragged() etc)
   * these are different because mouse events are queued to the end of
   * draw, so the previous position has to be updated on each event,
   * as opposed to the pmouseX/Y that's used inside draw, which is expected
   * to be updated once per trip through draw().
   */
  protected int emouseX, emouseY;

  /**
   * Used to set pmouseX/Y to mouseX/Y the first time mouseX/Y are used,
   * otherwise pmouseX/Y are always zero, causing a nasty jump.
   * 

   * Just using (frameCount == 0) won't work since mouseXxxxx()
   * may not be called until a couple frames into things.
   * 

   * @deprecated Please refrain from using this variable, it will be removed
   * from future releases of Processing because it cannot be used consistently
   * across platforms and input methods.
   */
  @Deprecated
  public boolean firstMouse = true;

  /**
   * When a mouse button is pressed, the value of the system variable
   * mouseButton is set to either LEFT, RIGHT, or
   * CENTER, depending on which button is pressed. (If no button is
   * pressed, mouseButton may be reset to 0. For that reason,
   * it's best to use mousePressed first to test if any button is being
   * pressed, and only then test the value of mouseButton, as shown in
   * the examples above.)
   *
   * 
Advanced:
   *
   * If running on macOS, a ctrl-click will be interpreted as the right-hand
   * mouse button (unlike Java, which reports it as the left mouse).
   * @webref input:mouse
   * @webBrief Shows which mouse button is pressed
   * @see PApplet#mouseX
   * @see PApplet#mouseY
   * @see PApplet#pmouseX
   * @see PApplet#pmouseY
   * @see PApplet#mousePressed
   * @see PApplet#mousePressed()
   * @see PApplet#mouseReleased()
   * @see PApplet#mouseClicked()
   * @see PApplet#mouseMoved()
   * @see PApplet#mouseDragged()
   * @see PApplet#mouseWheel(MouseEvent)
   */
  public int mouseButton;

  /**
   * The mousePressed variable stores whether a mouse button has been pressed.
   * The mouseButton variable (see the related reference entry) can be used to
   * determine which button has been pressed.
   * 


   * Mouse and keyboard events only work when a program has draw().
   * Without draw(), the code is only run once and then stops
   * listening for events.
   *
   * @webref input:mouse
   * @webBrief Variable storing if a mouse button is pressed
   * @see PApplet#mouseX
   * @see PApplet#mouseY
   * @see PApplet#pmouseX
   * @see PApplet#pmouseY
   * @see PApplet#mousePressed()
   * @see PApplet#mouseReleased()
   * @see PApplet#mouseClicked()
   * @see PApplet#mouseMoved()
   * @see PApplet#mouseDragged()
   * @see PApplet#mouseButton
   * @see PApplet#mouseWheel(MouseEvent)
   */
  public boolean mousePressed;

  // macOS: Ctrl + Left Mouse is converted to Right Mouse.
  // This boolean tracks whether the conversion happened on PRESS,
  // to report the same button during DRAG and on RELEASE,
  // even though CTRL might have been released already.
  // Otherwise, the events are inconsistent.
  // https://github.com/processing/processing/issues/5672
  private boolean macosCtrlClick;


  /** @deprecated Use a mouse event handler that passes an event instead. */
  @Deprecated
  public MouseEvent mouseEvent;

  /**
   * The system variable key always contains the value of the most
   * recent key on the keyboard that was used (either pressed or released).
   * 
 

   * For non-ASCII keys, use the keyCode variable. The keys included
   * in the ASCII specification (BACKSPACE, TAB, ENTER, RETURN, ESC, and
   * DELETE) do not require checking to see if they key is coded, and you
   * should simply use the key variable instead of keyCode If
   * you're making cross-platform projects, note that the ENTER key is
   * commonly used on PCs and Unix and the RETURN key is used instead on
   * Macintosh. Check for both ENTER and RETURN to make sure your program
   * will work for all platforms.
   * 


   * There are issues with how keyCode behaves across different
   * renderers and operating systems. Watch out for unexpected behavior as
   * you switch renderers and operating systems.
   *
   * Advanced
   *
   * Last key pressed.
   * 
   * If it's a coded key, i.e. UP/DOWN/CTRL/SHIFT/ALT,
   * this will be set to CODED (0xffff or 65535).
   *
   * @webref input:keyboard
   * @webBrief The system variable that always contains the value of the most
   * recent key on the keyboard that was used (either pressed or released)
   * @see PApplet#keyCode
   * @see PApplet#keyPressed
   * @see PApplet#keyPressed()
   * @see PApplet#keyReleased()
   */
  public char key;

  /**
   * The variable keyCode is used to detect special keys such as the
   * UP, DOWN, LEFT, RIGHT arrow keys and ALT, CONTROL, SHIFT.
   * 


   * When checking for these keys, it can be useful to first check if the key
   * is coded. This is done with the conditional if (key == CODED), as
   * shown in the example above.
   * 
 

   * The keys included in the ASCII specification (BACKSPACE, TAB, ENTER,
   * RETURN, ESC, and DELETE) do not require checking to see if the key is
   * coded; for those keys, you should simply use the key variable
   * directly (and not keyCode).  If you're making cross-platform
   * projects, note that the ENTER key is commonly used on PCs and Unix,
   * while the RETURN key is used on Macs. Make sure your program will work
   * on all platforms by checking for both ENTER and RETURN.
   * 
 

   * For those familiar with Java, the values for UP and DOWN are simply
   * shorter versions of Java's KeyEvent.VK_UP and KeyEvent.VK_DOWN.
   *  Other keyCode values can be found in the Java
   * KeyEvent
   * reference.
   * 


   * There are issues with how keyCode behaves across different
   * renderers and operating systems. Watch out for unexpected behavior
   * as you switch renderers and operating systems, and also whenever
   * you are using keys not mentioned in this reference entry.
   * 


   * If you are using P2D or P3D as your renderer, use the
   * NEWT KeyEvent constants.
   *
   * 
Advanced
   * When "key" is set to CODED, this will contain a Java key code.
   * 
   * For the arrow keys, keyCode will be one of UP, DOWN, LEFT and RIGHT.
   * ALT, CONTROL and SHIFT are also available. A full set of constants
   * can be obtained from java.awt.event.KeyEvent, from the VK_XXXX variables.
   *
   * @webref input:keyboard
   * @webBrief Used to detect special keys such as the UP, DOWN, LEFT, RIGHT arrow keys and ALT, CONTROL, SHIFT
   * @see PApplet#key
   * @see PApplet#keyPressed
   * @see PApplet#keyPressed()
   * @see PApplet#keyReleased()
   */
  public int keyCode;

  /**
   * The boolean system variable keyPressed is true
   * if any key is pressed and false if no keys are pressed.
   * 


   * Note that there is a similarly named function called keyPressed().
   * See its reference page for more information.
   *
   * @webref input:keyboard
   * @webBrief The boolean system variable that is true if any key
   * is pressed and false if no keys are pressed
   * @see PApplet#key
   * @see PApplet#keyCode
   * @see PApplet#keyPressed()
   * @see PApplet#keyReleased()
   */
  public boolean keyPressed;
  List pressedKeys = new ArrayList<>(6);

  /**
   * The last KeyEvent object passed into a mouse function.
   * @deprecated Use a key event handler that passes an event instead.
   */
  @Deprecated
  public KeyEvent keyEvent;

  /**
   *
   * Confirms if a Processing program is "focused", meaning that it is active
   * and will accept input from mouse or keyboard. This variable is true if
   * it is focused and false if not.
   *
   * @webref environment
   * @webBrief Confirms if a Processing program is "focused"
   */
  public boolean focused = false;

  /**
   * Time in milliseconds when the sketch was started.
   * 

   * Used by the millis() function.
   */
  long millisOffset = System.currentTimeMillis();

  /**
   *
   * The system variable frameRate contains the approximate frame rate
   * of the software as it executes. The initial value is 10 fps and is
   * updated with each frame. The value is averaged (integrated) over several
   * frames. As such, this value won't be valid until after 5-10 frames.
   *
   * @webref environment
   * @webBrief The system variable that contains the approximate frame rate
   * of the software as it executes
   * @see PApplet#frameRate(float)
   * @see PApplet#frameCount
   */
  public float frameRate = 60;

  protected boolean looping = true;

  /** flag set to true when redraw() is called by the user */
  protected boolean redraw = true;

  /**
   * The system variable frameCount contains the number o
   * frames displayed since the program started. Inside setup()
   * the value is 0 and during the first iteration of draw it is 1, etc.
   *
   * @webref environment
   * @webBrief The system variable that contains the number of frames
   * displayed since the program started
   * @see PApplet#frameRate(float)
   * @see PApplet#frameRate
   */
  public int frameCount;

  /** true if the sketch has stopped permanently. */
  public volatile boolean finished;

  /** used by the UncaughtExceptionHandler, so has to be static */
  static Throwable uncaughtThrowable;

  /**
   * true if exit() has been called so that things shut down
   * once the main thread kicks off.
   */
  protected boolean exitCalled;

  // ok to be static because it's not possible to mix enabled/disabled
  static protected boolean disableAWT;

  // messages to send if attached as an external vm

  /**
   * Position of the upper left-hand corner of the editor window
   * that launched this sketch.
   */
  static public final String ARGS_EDITOR_LOCATION = "--editor-location";

  static public final String ARGS_EXTERNAL = "--external";

  /**
   * Location for where to position the sketch window on screen.
   * 

   * This is used by the editor to when saving the previous sketch
   * location, or could be used by other classes to launch at a
   * specific position on-screen.
   */
  static public final String ARGS_LOCATION = "--location";

  /** Used by the PDE to suggest a display (set in prefs, passed on Run) */
  static public final String ARGS_DISPLAY = "--display";

  /** Disable AWT so that LWJGL and others can run */
  static public final String ARGS_DISABLE_AWT = "--disable-awt";

//  static public final String ARGS_SPAN_DISPLAYS = "--span";

  static public final String ARGS_BGCOLOR = "--bgcolor";

  static public final String ARGS_FULL_SCREEN = "--full-screen";

  static public final String ARGS_WINDOW_COLOR = "--window-color";

  static public final String ARGS_PRESENT = "--present";

  static public final String ARGS_STOP_COLOR = "--stop-color";

  static public final String ARGS_HIDE_STOP = "--hide-stop";

  /**
   * Allows the user or PdeEditor to set a specific sketch folder path.
   * 

   * Used by PdeEditor to pass in the location where saveFrame()
   * and all that stuff should write things.
   */
  static public final String ARGS_SKETCH_FOLDER = "--sketch-path";

  static public final String ARGS_UI_SCALE = "--ui-scale";

  /**
   * When run externally to a PdeEditor,
   * this is sent by the sketch when it quits.
   */
  static public final String EXTERNAL_STOP = "__STOP__";

  /**
   * When run externally to a PDE Editor, this is sent by the sketch
   * whenever the window is moved.
   * 

   * This is used so that the editor can re-open the sketch window
   * in the same position as the user last left it.
   */
  static public final String EXTERNAL_MOVE = "__MOVE__";

  /** true if this sketch is being run by the PDE */
  boolean external = false;

  static final String ERROR_MIN_MAX =
    "Cannot use min() or max() on an empty array.";


  // . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


  protected PSurface surface;


  public PSurface getSurface() {
    return surface;
  }


  // . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


  boolean insideSettings;

  String renderer = JAVA2D;
  int smooth = 1;  // default smoothing (whatever that means for the renderer)

  boolean fullScreen;
  int display = -1;  // use default
  // Unlike the others above, needs to be public to support
  // the pixelWidth and pixelHeight fields.
  public int pixelDensity = 1;

  boolean present;

  String outputPath;
  OutputStream outputStream;

  // Background default needs to be different from the default value in
  // PGraphics.backgroundColor, otherwise sketches that have size(100, 100)
  // appear to be larger than they are, because the bg color matches.
  // https://github.com/processing/processing/issues/2297
  int windowColor = 0xffDDDDDD;


  /**
   * @param method "size" or "fullScreen"
   * @param args parameters passed to the function to show the user
   * @return true if safely inside the settings() method
   */
  boolean insideSettings(String method, Object... args) {
    if (insideSettings) {
      return true;
    }
    final String url = "https://processing.org/reference/" + method + "_.html";
    if (!external) {  // post a warning for users of Eclipse and other IDEs
      StringList argList = new StringList(args);
      System.err.println("When not using the PDE, " + method + "() can only be used inside settings().");
      System.err.println("Remove the " + method + "() method from setup(), and add the following:");
      System.err.println("public void settings() {");
      System.err.println("  " + method + "(" + argList.join(", ") + ");");
      System.err.println("}");
    }
    throw new IllegalStateException(method + "() cannot be used here, see " + url);
  }


  void handleSettings() {
    insideSettings = true;

    if (!disableAWT) {
      displayWidth = ShimAWT.getDisplayWidth();
      displayHeight = ShimAWT.getDisplayHeight();
    } else {
      // https://github.com/processing/processing4/issues/57
      System.err.println("AWT disabled, displayWidth/displayHeight will be 0");
    }

    // Here's where size(), fullScreen(), smooth(N) and noSmooth() might
    // be called, conjuring up the demons of various rendering configurations.
    settings();

    if (display == SPAN && platform == MACOS) {
      // Make sure "Displays have separate Spaces" is unchecked
      // in System Preferences > Mission Control
      Process p = exec("defaults", "read", "com.apple.spaces", "spans-displays");
      BufferedReader outReader = createReader(p.getInputStream());
      BufferedReader errReader = createReader(p.getErrorStream());
      StringBuilder stdout = new StringBuilder();
      StringBuilder stderr = new StringBuilder();
      String line;
      try {
        while ((line = outReader.readLine()) != null) {
          stdout.append(line);
        }
        while ((line = errReader.readLine()) != null) {
          stderr.append(line);
        }
      } catch (IOException e) {
        printStackTrace(e);
      }

      int resultCode = -1;
      try {
        resultCode = p.waitFor();
      } catch (InterruptedException ignored) { }

      if (resultCode == 1) {
        String msg = trim(stderr.toString());
        // This message is confusing, so don't print if it's something typical
        if (!(msg.contains("The domain/default pair") && msg.contains("does not exist"))) {
          System.err.println("Could not check the status of “Displays have separate spaces.”");
          System.err.println("Result for 'defaults read' was " + resultCode);
          System.err.println(msg);
        }
      }

      String processOutput = trim(stdout.toString());
      // On Catalina, the option may not be set, so resultCode
      // will be 1 (an error, since the param doesn't exist.)
      // But "Displays have separate spaces" is on by default.
      // For Monterey, it appears to not be set until the user
      // has visited the Mission Control preference pane once.
      if (resultCode == 1 || "0".equals(processOutput)) {
        System.err.println("To use fullScreen(SPAN), visit System Preferences → Mission Control");
        System.err.println("and make sure that “Displays have separate spaces” is turned off.");
        System.err.println("Then log out and log back in.");
      }
    }

    insideSettings = false;
  }


  /**
   * The settings() function is new with Processing 3.0.
   * It's not needed in most sketches. It's only useful when it's
   * absolutely necessary to define the parameters to size()
   * with a variable. Alternately, the settings() function
   * is necessary when using Processing code outside the
   * Processing Development Environment (PDE). For example, when
   * using the Eclipse code editor, it's necessary to use
   * settings() to define the size() and
   * smooth() values for a sketch..
   * 
 

   * The settings() method runs before the sketch has been
   * set up, so other Processing functions cannot be used at that
   * point. For instance, do not use loadImage() inside settings().
   * The settings() method runs "passively" to set a few variables,
   * compared to the setup() command that call commands in
   * the Processing API.
   *
   * @webref environment
   * @webBrief Used when absolutely necessary to define the parameters to size()
   * with a variable
   * @see PApplet#fullScreen()
   * @see PApplet#setup()
   * @see PApplet#size(int,int)
   * @see PApplet#smooth()
   */
  public void settings() {
    // is this necessary? (doesn't appear to be, so removing)
    //size(DEFAULT_WIDTH, DEFAULT_HEIGHT, JAVA2D);
  }


  final public int sketchWidth() {
    return width;
  }


  final public int sketchHeight() {
    return height;
  }


  final public String sketchRenderer() {
    return renderer;
  }


  // smoothing 1 is default.. 0 is none.. 2,4,8 depend on renderer
  final public int sketchSmooth() {
    return smooth;
  }


  final public boolean sketchFullScreen() {
    return fullScreen;
  }


  // Numbered from 1, SPAN (0) means all displays, -1 means the default display
  final public int sketchDisplay() {
    return display;
  }


  final public String sketchOutputPath() {
    return outputPath;
  }


  final public OutputStream sketchOutputStream() {
    return outputStream;
  }


  final public int sketchWindowColor() {
    return windowColor;
  }


  final public int sketchPixelDensity() {
    return pixelDensity;
  }


  // . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

 /**
  *
  * This function returns the number "2" if the screen is a high-density
  * screen (called a Retina display on OS X or high-dpi on Windows and Linux)
  * and a "1" if not. This information is useful for a program to adapt to
  * run at double the pixel density on a screen that supports it.
  *
  * @webref environment
  * @webBrief Returns "2" if the screen is high-density and "1" if not
  * @see PApplet#pixelDensity(int)
  * @see PApplet#size(int,int)
  */
  public int displayDensity() {
    if (display != SPAN && (fullScreen || present)) {
      return displayDensity(display);
    }

    int displayCount = 0;
    if (!disableAWT) {
      displayCount = ShimAWT.getDisplayCount();
    } else {
      // https://github.com/processing/processing4/issues/57
      System.err.println("display count needs to be implemented for non-AWT");
    }
    // walk through all displays, use 2 if any display is 2
    for (int i = 0; i < displayCount; i++) {
      if (displayDensity(i+1) == 2) {
        return 2;
      }
    }
    // If nobody's density is 2 then everyone is 1
    return 1;
  }


 /**
  * @param display the display number to check
  * (1-indexed to match the Preferences dialog box)
  */
  public int displayDensity(int display) {
    if (!disableAWT) {
      return ShimAWT.getDisplayDensity(display);
    }
    /*
    if (display > 0 && display <= displayDevices.length) {
      GraphicsConfiguration graphicsConfig =
        displayDevices[display - 1].getDefaultConfiguration();
      AffineTransform tx = graphicsConfig.getDefaultTransform();
      return (int) Math.round(tx.getScaleX());
    }

    System.err.println("Display " + display + " does not exist, " +
                       "returning 1 for displayDensity(" + display + ")");
    */
    // https://github.com/processing/processing4/issues/57
    System.err.println("displayDensity() unavailable because AWT is disabled");
    return 1;  // not the end of the world, so don't throw a RuntimeException
  }


 /**
  * This function makes it possible to render using all the pixels
  * on high resolutions screens like Apple Retina and Windows HiDPI.
  * This function can only be run once within a program, and must
  * be called right after size() in a program without a
  * setup() function, or within setup() if present.
  * 

  * pixelDensity() should only be used with hardcoded
  * numbers (in almost all cases this number will be 2)
  * or in combination with displayDensity() as in the
  * third example above.
  * 

  * When the pixel density is set to more than 1, it changes  the
  * pixel operations including the way get(), set(),
  * blend(), copy(), and updatePixels()
  * all work. See the reference for pixelWidth and
  * pixelHeight for more information.
  * 

  * To use variables as the arguments to pixelDensity()
  * function, place the pixelDensity() function within
  * the settings() function. There is more information
  * about this on the settings() reference page.
  *
  * @webref environment
  * @webBrief It makes it possible for Processing to render using all the
  * pixels on high resolutions screens
  * @param density 1 or 2
  * @see PApplet#pixelWidth
  * @see PApplet#pixelHeight
  */
  public void pixelDensity(int density) {
    //println(density + " " + this.pixelDensity);
    if (density != this.pixelDensity) {
      if (insideSettings("pixelDensity", density)) {
        if (density != 1 && density != 2) {
          throw new RuntimeException("pixelDensity() can only be 1 or 2");
        }
        if (!FX2D.equals(renderer) && density == 2 && displayDensity() == 1) {
          // FX has its own check in PSurfaceFX
          // Don't throw exception because the sketch should still work
          System.err.println("pixelDensity(2) is not available for this display");
          this.pixelDensity = 1;
        } else {
          this.pixelDensity = density;
        }
      } else {
        System.err.println("not inside settings");
        // this should only be reachable when not running in the PDE,
        // so saying it's a settings()--not just setup()--issue should be ok
        throw new RuntimeException("pixelDensity() can only be used inside settings()");
      }
    }
  }


  /**
   * Called by PSurface objects to set the width and height variables,
   * and update the pixelWidth and pixelHeight variables.
   */
  public void setSize(int width, int height) {
    this.width = width;
    this.height = height;
    pixelWidth = width * pixelDensity;
    pixelHeight = height * pixelDensity;
  }


  // . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


  /**
   * @nowebref
   */
  public void smooth() {
    smooth(1);
  }

  /**
   * Draws all geometry with smooth (anti-aliased) edges.
   * This behavior is the default, so smooth() only needs
   * to be used when a program needs to set the smoothing
   * in a different way. The level parameter increases
   * the amount of smoothness. This is the level of over
   * sampling applied to the graphics buffer.
   * 

   * With the P2D and P3D renderers, smooth(2) is the
   * default, this is called "2x anti-aliasing." The code
   * smooth(4) is used for 4x anti-aliasing and smooth(8)
   * is specified for "8x anti-aliasing." The maximum
   * anti-aliasing level is determined by the hardware of
   * the machine that is running the software, so smooth(4)
   * and smooth(8) will not work with every computer.
   * 

   * The default renderer uses smooth(3) by default. This
   * is bicubic smoothing. The other option for the default
   * renderer is smooth(2), which is bilinear smoothing.
   * 

   * With Processing 3.0, smooth() is handled differently
   * than in earlier releases. In 2.x and earlier, it was possible
   * to use smooth() and noSmooth() to turn on
   * and off antialiasing within a sketch. Now, because of
   * how the software has changed, smooth() can only be set
   * once within a sketch. It can be used either at the top
   * of a sketch without a setup(), or after the size()
   * function when used in a sketch with setup(). The
   * noSmooth() function also follows the same rules.
   * 

   * When smooth() is used with a PGraphics object, it should
   * be run right after the object is created with
   * createGraphics(), as shown in the Reference in the third
   * example.
   *
   * @webref environment
   * @webBrief Draws all geometry with smooth (anti-aliased) edges
   * @param level either 2, 3, 4, or 8 depending on the renderer
   */
  public void smooth(int level) {
    if (insideSettings) {
      this.smooth = level;

    } else if (this.smooth != level) {
      smoothWarning("smooth");
    }
  }

  /**
   * Draws all geometry and fonts with jagged (aliased)
   * edges and images with hard edges between the pixels
   * when enlarged rather than interpolating pixels. Note
   * that smooth() is active by default, so it is necessary
   * to call noSmooth() to disable smoothing of geometry,
   * fonts, and images. Since the release of Processing 3.0,
   * the noSmooth() function can only be run once for each
   * sketch, either at the top of a sketch without a setup(),
   * or after the size() function when used in a sketch with
   * setup(). See the examples above for both scenarios.
   *
   * @webref environment
   * @webBrief Draws all geometry and fonts with jagged (aliased)
   * edges and images with hard edges between the pixels
   * when enlarged rather than interpolating pixels
   */
  public void noSmooth() {
    if (insideSettings) {
      this.smooth = 0;

    } else if (this.smooth != 0) {
      smoothWarning("noSmooth");
    }
  }


  private void smoothWarning(String method) {
    // When running from the PDE, say setup(), otherwise say settings()
    final String where = external ? "setup" : "settings";
    PGraphics.showWarning("%s() can only be used inside %s()", method, where);
    if (external) {
      PGraphics.showWarning("When run from the PDE, %s() is automatically moved from setup() to settings()", method);
    }
  }


  // . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


  public PGraphics getGraphics() {
    return g;
  }


  // TODO should this join the sketchXxxx() functions specific to settings()?
  public void orientation(int which) {
    // ignore calls to the orientation command
  }


  /**
   * Called by the application context to start running (or resume) the sketch.
   */
  public void start() {
    resume();
    handleMethods("resume");
    surface.resumeThread();
  }


  /**
   * Called by the application context to stop running (or pause) the sketch.
   */
  public void stop() {
    pause();
    handleMethods("pause");
    // calling this down here, since it's another thread it's safer to call
    // pause() and the registered pause methods first.
    surface.pauseThread();
  }


  /**
   * Sketch has been paused. Called when switching tabs in a browser or
   * swapping to a different application on Android. Also called just before
   * quitting. Use to safely disable things like serial, sound, or sensors.
   */
  public void pause() { }


  /**
   * Sketch has resumed. Called when switching tabs in a browser or
   * swapping to this application on Android. Also called on startup.
   * Use this to safely disable things like serial, sound, or sensors.
   */
  public void resume() { }


  //////////////////////////////////////////////////////////////


  /** Map of registered methods, stored by method name. */
  Map registerMap = new ConcurrentHashMap<>();


  class RegisteredMethods {
    /**
     * List of the objects for which the method is registered.
     * This is an ordered collection because the order of calls
     * likely matters, or at a minimum, needs to be stable.
     */
    Queue