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 GELLIPSE()
 Draw an ellipse or circle
------------------------------------------------------------------------------
 Syntax

     GELLIPSE(<nXc>,<nYc>,<nRadiusX>,<nRadiusY>,[<nDegStart>]
        [<nDegEnd>], [<nStyle>], [<nColor>], [<nMode>],
        [<nOutLineColor>], [<nHeight3D>]) --> NIL

 Arguments

     <nXc>, <nYc>, <nRadiusX>, and <nRadiusY> define the
     ellipse center point coordinates in pixels.

     Note:  If <nRadiusX> and <nRadiusY> have the same value, the result
     will be a circle.

     <nDegStart> is the value of the starting angle in degrees.  The
     default value is 0.

     <nDegEnd> is the value of the final angle in degrees.  The default
     value is 360.

     Note:  Changing the values of <nDegStart> and <nDegEnd> allows you
     to draw arcs of a circle or ellipse and sections of a "pie chart."

     <nStyle> defines the style of the ellipse using one of the constants
     listed in the table below:

     Ellipse Style Constants
     ------------------------------------------------------------------------
     Constant     Description
     ------------------------------------------------------------------------
     LLG_FILL     The ellipse is displayed first and then filled with the
                  color and mode specified below
     LLG_FRAME    Display of the ellipse is restricted to its contour in the
                  color and mode specified below
     ------------------------------------------------------------------------

     <nColor> is a numeric value representing the display color.  If this
     parameter is missing, the last color specified in a call to a CA-Clipper
     function is used.  The value range is limited to the number of colors
     available in the selected video mode.  In 16-color modes, valid values
     are between 0 and 15.  In 256-color modes, valid values are between 0
     and 255.

     <nMode> is a numeric value that represents the display mode.  The
     following are valid <nMode> values:

     Display Mode Constants
     ------------------------------------------------------------------------
     Constant       Description
     ------------------------------------------------------------------------
     LLG_MODE_SET   Display in SET mode (ignores any pixels present under the
                    line displayed).  This is the most common display mode.
     LLG_MODE_AND   Display in AND mode (executes an AND on pixels present
                    under the line at display time and on the display color).
     LLG_MODE_OR    Display in OR mode (executes an OR on pixels present
                    under the line at display time and on the display color).
     LLG_MODE_XOR   Display in XOR mode (executes an XOR on pixels present
                    under the line at display time and on the display color).
                    See note.
     ------------------------------------------------------------------------

     Note:  This method allows you to move objects around on the screen
     without damaging the background.  To retrieve the initial background,
     just repeat the call for display in XOR mode.  If the display mode
     parameter is missing, the last mode specified in a call to a CA-Clipper
     function is used.

     <nOutLineColor> is a numeric value representing the outline color.
     If this parameter is missing, the last color specified in a call to a
     CA-Clipper function is used.  The value range is limited to the number
     of colors available in the selected video mode.  In 16-color modes,
     valid values are between 0 and 15.  In 256-color modes, valid values are
     between 0 and 255.

     <nHeight3D> is a numeric value representing the height of the 3-D
     effect in pixels.

 Returns

     GELLIPSE() always returns NIL.

 Description

     GELLIPSE() draws an ellipse or circle.  This function can be used only
     if you have set the screen to a graphic mode using SET VIDEOMODE.  This
     function respects the constraints defined by GSETCLIP().

 Examples

     .  This example displays an ellipse in a region limited by
        clipping:

        // Switch to graphic mode

        SET VIDEOMODE TO LLG_VIDEO_VGA_640_480_16
        // Restrict the display region to one portion of the screen
        GSETCLIP(100,100,300,300)
        // Draw a quarter section of an ellipse
        GELLIPSE(200, 200, 160, 230, 045,;

           135, LLG_FILL, 12, LLG_MODE_SET)
        QUIT                            // End of application

 Files   Library is LLIBG.LLB, header file is Llibg.ch.


See Also: GLINE() GPOLYGON() GRECT() GWRITEAT() GBMPDISP()
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