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(upper left first, then lower right) specified, using the
color index specified. 
<PRE>
... inside a function ...
<A HREF="#gdImagePtr">gdImagePtr</A> im;
int black;
int white;
im = <A HREF="#gdImageCreate">gdImageCreate</A>(100, 100);
/* Background color (first allocated) */
black = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 0, 0, 0);	
/* Allocate the color white (red, green and blue all maximum). */
white = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 255, 255, 255);	
/* Draw a rectangle occupying the central area. */
gdImageRectangle(im, 25, 25, 74, 74, white);
/* ... Do something with the image, such as saving it to a file... */
/* Destroy it */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
</PRE>
<DT><A NAME="gdImageFilledPolygon">void gdImageFilledPolygon(gdImagePtr im, gdPointPtr points, int pointsTotal, int color)</A>
<STRONG>(FUNCTION)</STRONG> 
<DD>
gdImageFilledPolygon is used to fill a polygon with the verticies
(at least 3) specified, using the color index specified. 
See also <A HREF="#gdImageFilledPolygon">gdImagePolygon</A>.
<PRE>
... inside a function ...
<A HREF="#gdImagePtr">gdImagePtr</A> im;
int black;
int white;
int red;
/* Points of polygon */
<A HREF="#gdPoint">gdPoint</A> points[3];
im = <A HREF="#gdImageCreate">gdImageCreate</A>(100, 100);
/* Background color (first allocated) */
black = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 0, 0, 0);	
/* Allocate the color white (red, green and blue all maximum). */
white = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 255, 255, 255);	
/* Allocate the color red. */
red = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 255, 0, 0);	
/* Draw a triangle. */
points[0].x = 50;
points[0].y = 0;
points[1].x = 99;
points[1].y = 99;
points[2].x = 0;
points[2].y = 99;
/* Paint it in white */
gdImageFilledPolygon(im, points, 3, white);
/* Outline it in red; must be done second */
<A HREF="#gdImagePolygon">gdImagePolygon</A>(im, points, 3, red);
/* ... Do something with the image, such as saving it to a file... */
/* Destroy it */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
</PRE>
<DT><A NAME="gdImageFilledRectangle">void gdImageFilledRectangle(gdImagePtr im, int x1, int y1, int x2, int y2, int color)</A>
<STRONG>(FUNCTION)</STRONG> 
<DD>
gdImageFilledRectangle is used to draw a solid rectangle with the two corners
(upper left first, then lower right) specified, using the
color index specified. 
<PRE>
... inside a function ...
<A HREF="#gdImagePtr">gdImagePtr</A> im;
int black;
int white;
im = <A HREF="#gdImageCreate">gdImageCreate</A>(100, 100);
/* Background color (first allocated) */
black = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 0, 0, 0);	
/* Allocate the color white (red, green and blue all maximum). */
white = <A HREF="#gdImageColorAllocate">int gdImageColorAllocate</A>(im, 255, 255, 255);	
/* Draw a filled rectangle occupying the central area. */
gdImageFilledRectangle(im, 25, 25, 74, 74, white);
/* ... Do something with the image, such as saving it to a file... */
/* Destroy it */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
</PRE>
<DT><A NAME="gdImageArc">void gdImageArc(gdImagePtr im, int cx, int cy, int w, int h, int s, int e, int color)</A>
<STRONG> (FUNCTION)</STRONG> 
<DD>
gdImageArc is used to draw a partial ellipse centered at the given point,
with the specified width and height in pixels. The arc begins at
the position in degrees specified by <code>s</code> and ends at
the position specified by <code>e</code>. The arc is drawn in
the color specified by the last argument. A circle can be drawn
by beginning from 0 degrees and ending at 360 degrees, with
width and height being equal. e must be greater than s. Values greater 
than 360 are interpreted modulo 360.
<PRE>
... inside a function ...
<A HREF="#gdImagePtr">gdImagePtr</A> im;
int black;
int white;
im = <A HREF="#gdImageCreate">gdImageCreate</A>(100, 50);
/* Background color (first allocated) */
black = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 0, 0, 0);	
/* Allocate the color white (red, green and blue all maximum). */
white = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 255, 255, 255);	
/* Inscribe an ellipse in the image. */
gdImageArc(im, 50, 25, 98, 48, 0, 360, white);
/* ... Do something with the image, such as saving it to a file... */
/* Destroy it */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
</PRE>
<DT><A NAME="gdImageFillToBorder">void gdImageFillToBorder(gdImagePtr im, int x, int y, int border, int color)
<STRONG> (FUNCTION)</STRONG> 
<DD>
gdImageFillToBorder floods a portion of the image with the specified
<code>color</code>, beginning at the specified point and stopping at 
the specified <code>border</code> color. For a way of flooding an
area defined by the color of the starting point, see
<A HREF="#gdImageFill">gdImageFill</A>.
<P>
The border color <em>cannot</em> be a special color
such as <A HREF="#gdTiled">gdTiled</A>; it must be a proper
solid color. The fill color can be, however.
<P>
Note that gdImageFillToBorder is recursive. It is not the most
naive implementation possible, and the implementation is
expected to improve, but there will always be degenerate
cases in which the stack can become very deep. This can be
a problem in MSDOS and MS Windows environments. (Of course,
in a Unix or NT environment with a proper stack, this is
not a problem at all.)
<PRE>
... inside a function ...
<A HREF="#gdImagePtr">gdImagePtr</A> im;
int black;
int white;
int red;
im = <A HREF="#gdImageCreate">gdImageCreate</A>(100, 50);
/* Background color (first allocated) */
black = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 0, 0, 0);	
/* Allocate the color white (red, green and blue all maximum). */
white = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 255, 255, 255);	
/* Allocate the color red. */
red = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 255, 0, 0);	
/* Inscribe an ellipse in the image. */
gdImageArc(im, 50, 25, 98, 48, 0, 360, white);
/* Flood-fill the ellipse. Fill color is red, border color is 
	white (ellipse). */
gdImageFillToBorder(im, 50, 50, white, red);
/* ... Do something with the image, such as saving it to a file... */
/* Destroy it */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
</PRE>
<DT><A NAME="gdImageFill">void gdImageFill(gdImagePtr im, int x, int y, int color)
<STRONG> (FUNCTION)</STRONG> 
<DD>
gdImageFill floods a portion of the image with the specified
<code>color</code>, beginning at the specified point and flooding the
surrounding region of the same color as the starting point.
For a way of flooding a region defined by a specific border
color rather than by its interior color, see
<A HREF="#gdImageFillToBorder">gdImageFillToBorder</A>.
<P>
The fill color can be <A HREF="#gdTiled">gdTiled</A>, resulting
in a tile fill using another image as the tile. However,
the tile image cannot be transparent. If the image you wish
to fill with has a transparent color index, call
<A HREF="#gdImageTransparent">gdImageTransparent</A> on the
tile image and set the transparent color index to -1 
to turn off its transparency.
<P>
Note that gdImageFill is recursive. It is not the most
naive implementation possible, and the implementation is
expected to improve, but there will always be degenerate
cases in which the stack can become very deep. This can be
a problem in MSDOS and MS Windows environments. (Of course,
in a Unix or NT environment with a proper stack, this is
not a problem at all.)
<PRE>
... inside a function ...
<A HREF="#gdImagePtr">gdImagePtr</A> im;
int black;
int white;
int red;
im = <A HREF="#gdImageCreate">gdImageCreate</A>(100, 50);
/* Background color (first allocated) */
black = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 0, 0, 0);	
/* Allocate the color white (red, green and blue all maximum). */
white = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 255, 255, 255);	
/* Allocate the color red. */
red = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 255, 0, 0);	
/* Inscribe an ellipse in the image. */
gdImageArc(im, 50, 25, 98, 48, 0, 360, white);
/* Flood-fill the ellipse. Fill color is red, and will replace the
	black interior of the ellipse. */
gdImageFill(im, 50, 50, red);
/* ... Do something with the image, such as saving it to a file... */
/* Destroy it */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
</PRE>
<DT><A NAME="gdImageSetBrush">void gdImageSetBrush(gdImagePtr im, gdImagePtr brush)</A>
<STRONG>(FUNCTION)</STRONG> 
<DD>
A "brush" is an image used to draw wide, shaped strokes in another image. Just
as a paintbrush is not a single point, a brush image need not be
a single pixel. <em>Any</em> gd image can be used as a brush, and by
setting the transparent color index of the brush image with
<A HREF="#gdImageColorTransparent">gdImageColorTransparent</A>,
a brush of any shape can be created. All line-drawing functions,
such as <A HREF="#gdImageLine">gdImageLine</A> and
<A HREF="#gdImagePolygon">gdImagePolygon</A>, will use the
current brush if the special "color" <A HREF="#gdBrushed">
gdBrushed</A> or <A HREF="#gdStyledBrushed">gdStyledBrushed</A>
is used when calling them.
<P>
gdImageSetBrush is used to specify the brush to be used in a
particular image. You can set any image to be the brush.
If the brush image does not have the same color map as the
first image, any colors missing from the first image
will be allocated. If not enough colors can be allocated,
the closest colors already available will be used. This
allows arbitrary GIFs to be used as brush images. It also
means, however, that you should not set a brush unless you
will actually use it; if you set a rapid succession of
different brush images, you can quickly fill your color map,
and the results will not be optimal.
<P>
You need not take any special action when you are finished
with a brush. As for any other image, if you will not
be using the brush image for any further purpose,
you should call <A HREF="#gdImageDestroy">gdImageDestroy</A>.
You must not use the color <A HREF="#gdBrushed">gdBrushed</A>
if the current brush has been destroyed; you can of
course set a new brush to replace it.
<PRE>
... inside a function ...
<A HREF="#gdImagePtr">gdImagePtr</A> im, brush;
FILE *in;
int black;
im = <A HREF="#gdImageCreate">gdImageCreate</A>(100, 100);
/* Open the brush GIF. For best results, portions of the
	brush that should be transparent (ie, not part of the
	brush shape) should have the transparent color index. */
in = fopen("star.gif", "rb");
brush = <A HREF="#gdImageCreateFromGif">gdImageCreateFromGif</A>(in);
/* Background color (first allocated) */
black = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 0, 0, 0);	
gdImageSetBrush(im, brush);
/* Draw a line from the upper left corner to the lower right corner
	using the brush. */
<A HREF="#gdImageLine">gdImageLine</A>(im, 0, 0, 99, 99, <A HREF="#gdBrushed">gdBrushed</A>);
/* ... Do something with the image, such as saving it to a file... */
/* Destroy it */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
/* Destroy the brush image */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(brush);
</PRE>
<DT><A NAME="gdImageSetTile">void gdImageSetTile(gdImagePtr im, gdImagePtr tile)</A>
<STRONG>(FUNCTION)</STRONG> 
<DD>
A "tile" is an image used to fill an area with  a repeated pattern.
<em>Any</em> gd image can be used as a tile, and by
setting the transparent color index of the tile image with
<A HREF="#gdImageColorTransparent">gdImageColorTransparent</A>,
a tile that allows certain parts of the underlying area to shine
through can be created. All region-filling functions,
such as <A HREF="#gdImageFill">gdImageFill</A> and
<A HREF="#gdImageFilledPolygon">gdImageFilledPolygon</A>, will use the
current tile if the special "color" <A HREF="#gdTiled">
gdTiled</A> is used when calling them.
<P>
gdImageSetTile is used to specify the tile to be used in a
particular image. You can set any image to be the tile.
If the tile image does not have the same color map as the
first image, any colors missing from the first image
will be allocated. If not enough colors can be allocated,
the closest colors already available will be used. This
allows arbitrary GIFs to be used as tile images. It also
means, however, that you should not set a tile unless you
will actually use it; if you set a rapid succession of
different tile images, you can quickly fill your color map,
and the results will not be optimal.
<P>
You need not take any special action when you are finished
with a tile. As for any other image, if you will not
be using the tile image for any further purpose,
you should call <A HREF="#gdImageDestroy">gdImageDestroy</A>.
You must not use the color <A HREF="#gdBrushed">gdTiled</A>
if the current tile has been destroyed; you can of
course set a new tile to replace it.
<PRE>
... inside a function ...
<A HREF="#gdImagePtr">gdImagePtr</A> im, tile;
FILE *in;
int black;
im = <A HREF="#gdImageCreate">gdImageCreate</A>(100, 100);
/* Open the tile GIF. For best results, portions of the
	tile that should be transparent (ie, allowing the
	background to shine through) should have the transparent 
	color index. */
in = fopen("star.gif", "rb");
tile = <A HREF="#gdImageCreateFromGif">gdImageCreateFromGif</A>(in);
/* Background color (first allocated) */
black = <A HREF="#gdImageColorAllocate">gdImageColorAllocate</A>(im, 0, 0, 0);	
gdImageSetTile(im, tile);
/* Fill an area using the tile. */
<A HREF="#gdImageFilledRectangle">gdImageFilledRectangle</A>(im, 25, 25, 75, 75, <A HREF="#gdTiled">gdTiled</A>);
/* ... Do something with the image, such as saving it to a file... */
/* Destroy it */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
/* Destroy the tile image */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(tile);
</PRE>
<DT><A NAME="gdImageSetStyle">void gdImageSetStyle(gdImagePtr im, int *style, int styleLength)</A>
<STRONG>(FUNCTION)</STRONG> 
<DD>
It is often desirable to draw dashed lines, dotted lines, and other
variations on a broken line. gdImageSetStyle can be used to set
any desired series of colors, including a special color that
leaves the background intact, to be repeated during the drawing
of a line. 
<P>
To use gdImageSetStyle, create an array of integers and assign
them the desired series of color values to be repeated. 
You can assign the special color value <A HREF="#gdTransparent">
gdTransparent</A> to indicate that the existing color should
be left unchanged for that particular pixel (allowing a dashed
line to be attractively drawn over an existing image). 
<P>
Then, to draw a line using the style, use the normal