extgraph.h

These libraries are designed for use with Microsoft Visual C++ version 6.0. Install them by running

 *
 *    Black, Dark Gray, Gray, Light Gray, White,
 *    Red, Yellow, Green, Cyan, Blue, Magenta
 *
 * The first line corresponds to standard gray scales and the
 * second to the primary and secondary colors of light.  The
 * built-in set is limited to these colors because they are
 * likely to be the same on all hardware devices.  For finer
 * color control, you can use the DefineColor function to
 * create new color names as well.
 */

void SetPenColor(string color);

/*
 * Function: GetPenColor
 * Usage: color = GetPenColor();
 * -----------------------------
 * This function returns the current pen color as a string.
 */

string GetPenColor(void);

/*
 * Function: DefineColor
 * Usage: DefineColor(name, red, green, blue);
 * -------------------------------------------
 * This function allows the client to define a new color name
 * by supplying intensity levels for the colors red, green,
 * and blue, which are the primary colors of light.  The
 * color values are provided as real numbers between 0 and 1,
 * indicating the intensity of that color.  For example,
 * the predefined color Magenta has full intensity red and
 * blue but no green and is therefore defined as:
 *
 *      DefineColor("Magenta", 1, 0, 1);
 *
 * DefineColor allows you to create intermediate colors on
 * many displays, although the results vary significantly
 * depending on the hardware.  For example, the following
 * usually gives a reasonable approximation of brown:
 *
 *      DefineColor("Brown", .35, .20, .05);
 */

void DefineColor(string name,
                 double red, double green, double blue);

/* Section 7 -- Pictures */

/*
 * Function: DrawNamedPicture
 * Usage: DrawNamedPicture(name);
 * ------------------------------
 * This function looks for a graphical resource with the
 * specified name and copies it to the graphics window
 * so that the lower left corner of the image appears
 * at the current point.  The function generates an error
 * if the named picture cannot be found.  Note that,
 * although the interface presented here is the same for
 * all systems, the format used for the resource itself
 * and the mechanism used to name it may not be portable
 * from one machine to another.  To port an application
 * between platforms, some conversion of the associated
 * resources is usually required.
 */

void DrawNamedPicture(string name);

/*
 * Functions: GetPictureWidth, GetPictureHeight
 * Usage: w = GetPictureWidth("name");
 *        h = GetPictureHeight("name");
 * ------------------------------------
 * These functions return the width and height (in inches)
 * of the named picture resource, as described in the comments
 * for DrawNamedPicture.
 */

double GetPictureWidth(string name);
double GetPictureHeight(string name);


/* Section 8 -- Miscellaneous functions */

/*
 * Function: SetEraseMode
 * Usage: SetEraseMode(TRUE);
 *        SetEraseMode(FALSE);
 * ---------------------------
 * The SetEraseMode function sets the value of the internal
 * erasing flag.  Setting this flag is similar to setting the
 * color to "White" in its effect but does not affect the
 * current color setting.  When erase mode is set to FALSE,
 * normal drawing is restored, using the current color.
 *
 * It is an error to enable Erase mode and XOR mode at the same time.
 */

void SetEraseMode(bool mode);

/*
 * Function: GetEraseMode
 * Usage: mode = GetEraseMode();
 * -----------------------------
 * This function returns the current state of the erase mode flag.
 */

bool GetEraseMode(void);

/*
 * Function: SetWindowTitle
 * Usage: SetWindowTitle(title);
 * -----------------------------
 * This function sets the title of the graphics window, if such
 * an operation is possible on the display.  If it is not possible
 * for a particular implementation, the call is simply ignored.
 * This function may be called prior to the InitGraphics call to
 * set the initial name of the window.
 */

void SetWindowTitle(string title);

/*
 * Function: GetWindowTitle
 * Usage: title = GetWindowTitle();
 * --------------------------------
 * This function returns the title of the graphics window.  If the
 * implementation does not support titles, this call returns the
 * empty string.
 */

string GetWindowTitle(void);

/*
 * Function: UpdateDisplay
 * Usage: UpdateDisplay();
 * -----------------------
 * This function initiates an immediate update of the graphics
 * window and is necessary for animation.  Ordinarily, the
 * graphics window is updated only when the program waits for
 * user input.
 */

void UpdateDisplay(void);

/*
 * Function: Pause
 * Usage: Pause(seconds);
 * ----------------------
 * The Pause function updates the graphics window and then
 * pauses for the indicated number of seconds.  This function
 * is useful for animation where the motion would otherwise
 * be too fast.
 */

void Pause(double seconds);

/*
 * Function: ExitGraphics
 * Usage: ExitGraphics();
 * ----------------------
 * The ExitGraphics function closes the graphics window and
 * exits from the application without waiting for any additional
 * user interaction.
 */

void ExitGraphics(void);

/*
 * Functions: SaveGraphicsState, RestoreGraphicsState
 * Usage: SaveGraphicsState();
 *        . . . graphical operations . . .
 *        RestoreGraphicsState();
 * ---------------------------------------------------
 * The SaveGraphicsState function saves the current graphics
 * state (the current pen position, the font, the point size,
 * and the erase mode flag) internally, so that they can be
 * restored by the next RestoreGraphicsState call.  These two
 * functions must be used in pairs but may be nested to any depth.
 */

void SaveGraphicsState(void);
void RestoreGraphicsState(void);

/*
 * Functions: GetFullScreenWidth, GetFullScreenHeight
 * Usage: width = GetFullScreenWidth();
 *        height = GetFullScreenHeight();
 * --------------------------------------
 * These functions return the height and width of the entire
 * display screen, not the graphics window.  Their only
 * significant use is for applications that need to adjust
 * the size of the graphics window based on available screen
 * space.  These functions may be called before InitGraphics
 * has been called.
 */

double GetFullScreenWidth(void);
double GetFullScreenHeight(void);

/*
 * Functions: SetWindowSize
 * Usage: SetWindowSize(width, height);
 * ------------------------------------
 * This function sets the window size to the indicated dimensions,
 * if possible.  This function should be called before the graphics
 * window is created by InitGraphics.  Attempts to change the size
 * of an existing window are ignored by most implementations.  This
 * function should be used sparingly because it reduces the
 * portability of applications, particularly if the client
 * requests more space than is available on the screen.
 */

void SetWindowSize(double width, double height);

/*
 * Functions: GetXResolution, GetYResolution
 * Usage: xres = GetXResolution();
 *        yres = GetYResolution();
 * -----------------------------------------
 * These functions return the number of pixels per inch along
 * each of the coordinate directions and are useful for applications
 * in which it is important for short distances to be represented
 * uniformly in terms of dot spacing.  Even though the x and y
 * resolutions are the same for most displays, clients should
 * not rely on this property.
 *
 * Note: Lines in the graphics library are one pixel unit wide and
 * have a length that is always one pixel longer than you might
 * expect.  For example, the function call
 *
 *     DrawLine(2 / GetXResolution(), 0);
 *
 * draws a line from the current point to the point two pixels
 * further right, which results in a line of three pixels.
 */

double GetXResolution(void);
double GetYResolution(void);

/*
 * Function: SetXORMode
 * Usage: SetXORMode(TRUE);
 *        SetXORMode(FALSE);
 * ---------------------------
 * The SetXORMode function sets the value of the internal
 * XOR-drawing flag.  When this flag is set, wherever you
 * draw will turn to the opposite of its existing color;
 * this kind of drawing has the property that if you do it
 * twice in a row (without changing anything else), the display
 * will end up back how it started.  This type of drawing is
 * useful for animations and "rubber-band" selection.
 * When XOR mode is set to FALSE, normal drawing resumes
 * (the result of a draw operation depends only on that draw
 * operation, and not what was already on the screen).
 *
 * It is an error to enable XOR mode and Erase mode at the same time.
 *
 * Caveat: This operation may not be portable to other
 * implementations of the graphics library.
 */

void SetXORMode(bool mode);

/*
 * Function: GetXORMode
 * Usage: mode = GetXORMode();
 * -----------------------------
 * This function returns the current state of the XOR mode flag.
 */

bool GetXORMode(void);

#endif