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- sync to 1.4.0

master
pierre 2006-04-05 15:34:22 +00:00
parent 4990220173
commit 3d209b2ed9
9 changed files with 5374 additions and 434 deletions
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16
src/Makefile
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@ -9,26 +9,24 @@
CC=gcc
AR=ar
ARFLAGS=rc
CFLAGS=-O
LIB=libgd.a
LIBS=-L./ -lgd -lm
all: $(LIB) gddemo giftogd webgif
all: libgd.a gddemo giftogd webgif
gddemo: gddemo.o $(LIB) gd.h gdfonts.h gdfontl.h
gddemo: gddemo.o libgd.a gd.h gdfonts.h gdfontl.h
$(CC) gddemo.o -o gddemo $(LIBS)
giftogd: giftogd.o $(LIB) gd.h
giftogd: giftogd.o libgd.a gd.h
$(CC) giftogd.o -o giftogd $(LIBS)
$(LIB): gd.o gdfontt.o gdfonts.o gdfontmb.o gdfontl.o gdfontg.o \
libgd.a: gd.o gdfontt.o gdfonts.o gdfontmb.o gdfontl.o gdfontg.o \
gd.h gdfontt.h gdfonts.h gdfontmb.h gdfontl.h gdfontg.h
rm -f $(LIB)
$(AR) $(ARFLAGS) $(LIB) gd.o gdfontt.o gdfonts.o gdfontmb.o \
rm -f libgd.a
$(AR) rc libgd.a gd.o gdfontt.o gdfonts.o gdfontmb.o \
gdfontl.o gdfontg.o
webgif: webgif.o $(LIB) gd.h
webgif: webgif.o libgd.a gd.h
$(CC) webgif.o -o webgif $(LIBS)
clean:

3
src/bdf-howto.txt Normal file
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@ -0,0 +1,3 @@
fstobdf -server 10.1.1.2:7100 -fn -adobe-courier-bold-r-normal--14-100-
100-100-m-90-iso8859-1 | ./bdftogd FontAdobe gdfonta

10
src/bdftogd
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@ -136,20 +136,22 @@ $info
char ${gdname}Data[] = {
EOF
for my $i (0 .. 255)
my($i);
for $i (0 .. 255)
{
$data[$i] = '' unless defined $data[$i];
$data[$i] = '0' x ($width * $height - length $data[$i]) . $data[$i];
print FILEC "/* Char $i */\n";
for my $line (0 .. $height - 1)
my($line);
for $line (0 .. $height - 1)
{ print FILEC join ',', split(//, substr($data[$i], $line * $width, $width)), "\n"; }
print FILEC "\n";
next;
for my $line (0 .. $height - 1)
my($line);
for $line (0 .. $height - 1)
{ print substr($data[$i], $line * $width, $width), "\n"; }
}

486
src/gd.c
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37
src/gd.h
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@ -20,7 +20,7 @@
/* Image type. See functions below; you will not need to change
the elements directly. Use the provided macros to
access sx, sy, the color table, and colorsTotal for
access sx, sy, the color table, and colorsTotal for
read-only purposes. */
typedef struct gdImageStruct {
@ -30,13 +30,13 @@ typedef struct gdImageStruct {
int colorsTotal;
int red[gdMaxColors];
int green[gdMaxColors];
int blue[gdMaxColors];
int blue[gdMaxColors];
int open[gdMaxColors];
int transparent;
int *polyInts;
int polyAllocated;
struct gdImageStruct *brush;
struct gdImageStruct *tile;
struct gdImageStruct *tile;
int brushColorMap[gdMaxColors];
int tileColorMap[gdMaxColors];
int styleLength;
@ -86,6 +86,22 @@ gdImagePtr gdImageCreate(int sx, int sy);
gdImagePtr gdImageCreateFromGif(FILE *fd);
gdImagePtr gdImageCreateFromGd(FILE *in);
gdImagePtr gdImageCreateFromXbm(FILE *fd);
/* A custom data source. */
/* The source function must return -1 on error, otherwise the number
of bytes fetched. 0 is EOF, not an error! */
/* context will be passed to your source function. */
typedef struct {
int (*source) (void *context, char *buffer, int len);
void *context;
} gdSource, *gdSourcePtr;
gdImagePtr gdImageCreateFromGifSource(
gdSourcePtr in);
void gdImageDestroy(gdImagePtr im);
void gdImageSetPixel(gdImagePtr im, int x, int y, int color);
int gdImageGetPixel(gdImagePtr im, int x, int y);
@ -120,7 +136,22 @@ int gdImageColorClosest(gdImagePtr im, int r, int g, int b);
int gdImageColorExact(gdImagePtr im, int r, int g, int b);
void gdImageColorDeallocate(gdImagePtr im, int color);
void gdImageColorTransparent(gdImagePtr im, int color);
/* A custom data sink. */
/* The sink function must return -1 on error, otherwise the number
of bytes written, which must be equal to len. */
/* context will be passed to your sink function. */
typedef struct {
int (*sink) (void *context, char *buffer, int len);
void *context;
} gdSink, *gdSinkPtr;
void gdImageGif(gdImagePtr im, FILE *out);
void gdImageGifToSink(gdImagePtr im, gdSinkPtr out);
void gdImageGd(gdImagePtr im, FILE *out);
void gdImageArc(gdImagePtr im, int cx, int cy, int w, int h, int s, int e, int color);
void gdImageFillToBorder(gdImagePtr im, int x, int y, int border, int color);

4638
src/gdfonta.c Normal file
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21
src/gdfonta.h Normal file
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@ -0,0 +1,21 @@
#ifndef _GDFONTA_H_
#define _GDFONTA_H_ 1
/*
This is a header file for gd font, generated using
bdftogd version 0.51 by Jan Pazdziora, adelton@fi.muni.cz
from bdf font
-Adobe-Courier-Bold-R-Normal--14-100-100-100-M-90-ISO8859-1
at Sun Jul 19 12:41:12 1998.
The original bdf was holding following copyright:
"Copyright (c) 1984, 1987 Adobe Systems Incorporated. All Rights Reserved. Copyright (c) 1988, 1991 Digital Equipment Corporation. All Rights Reserved."
*/
#include "gd.h"
extern gdFontPtr gdFontAdobe;
#endif

165
src/index.html
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@ -1,9 +1,9 @@
<HTML>
<HEAD>
<TITLE>gd 1.3</TITLE>
<TITLE>gd 1.4</TITLE>
</HEAD>
<BODY>
<H1>gd 1.3</H1>
<H1>gd 1.4</H1>
<H2>A graphics library for fast GIF creation</H2>
<H2>Follow this link to the
<A HREF="http://www.boutell.com/gd/">latest version
@ -11,7 +11,7 @@ of this document</A>.</H2>
<H3>Table of Contents</H3>
<UL>
<LI><A HREF="#notice">Credits and license terms</A>
<LI><A HREF="#whatsnew1.3">What's new in version 1.3?</A>
<LI><A HREF="#whatsnew1.4">What's new in version 1.4?</A>
<LI><A HREF="#whatis">What is gd?</A>
<LI><A HREF="#gdother">What if I want to use another programming language?</A>
<LI><A HREF="#required">What else do I need to use gd?</A>
@ -115,12 +115,34 @@ text file from whatever scripting language you prefer to use, then
invoke the interpreter.
<p>
These packages are based on gd 1.2 as of this writing but should
be compatible with gd 1.3 with minimal tweaking.
be compatible with gd 1.3x with minimal tweaking.
<ul>
<li><a href="http://s27w007.pswfs.gov/tgd/">tgd</a>, by Bradley K. Sherman
<li><a href="http://www.unimelb.edu.au/fly/fly.html">fly</a>, by Martin Gleeson
</ul>
<P><A NAME="whatsnew1.2"><H3>What's new in version 1.3?</H3></A>
<P><A NAME="whatsnew1.4"><H3>What's new in version 1.4?</H3></A>
Version 1.4 features the following changes:
<dl>
<dt>Fixed polygon fill routine (again)
<dd>Thanks to Kirsten Schulz, version 1.4 is able to fill
numerous types of polygons that caused problems with
previous releases, including version 1.3.
<dt>Support for alternate data sources
<dd>Programmers who wish to load a GIF from something other
than a stdio FILE * stream can use the new
<a href="#gdImageCreateFromGifSource">gdImageCreateFromGifSource</a> function.
<dt>Support for alternate data destinations
<dd>Programmers who wish to write a GIF to something other
than a stdio FILE * stream can use the new
<a href="#gdImageGifToSink">gdImageGifToSink</a> function.
<dt>More tolerant when reading GIFs
<dd>
Version 1.4 does not crash when reading certain animated GIFs,
although it still only reads the first frame. Version 1.4 also has
overflow testing code to prevent crashes when reading
damaged GIFs.
</dl>
<P><A NAME="whatsnew1.3"><H3>What's new in version 1.3?</H3></A>
Version 1.3 features the following changes:
<dl>
<dt>Non-LZW-based GIF compression code
@ -187,13 +209,13 @@ your particular system.
<A NAME="getgd"><H3>How do I get gd?</H3></A>
<h4>By HTTP</h4>
<ul>
<li><a href="http://www.boutell.com/gd/http/gd1.3.tar.gz">Gzipped Tar File (Unix)</a>
<li><a href="http://www.boutell.com/gd/http/gd13.zip">.ZIP File (Windows)</a>
<li><a href="http://www.boutell.com/gd/http/gd1.4.tar.gz">Gzipped Tar File (Unix)</a>
<li><a href="http://www.boutell.com/gd/http/gd14.zip">.ZIP File (Windows)</a>
</ul>
<h4>By FTP</h4>
<ul>
<li><a href="ftp://ftp.boutell.com/pub/boutell/gd/gd1.3.tar.gz">Gzipped Tar File (Unix)</a>
<li><a href="ftp://ftp.boutell.com/pub/boutell/gd/gd13.zip">.ZIP File (Windows)</a>
<li><a href="ftp://ftp.boutell.com/pub/boutell/gd/gd1.4.tar.gz">Gzipped Tar File (Unix)</a>
<li><a href="ftp://ftp.boutell.com/pub/boutell/gd/gd14.zip">.ZIP File (Windows)</a>
</ul>
<P>
<A NAME="buildgd"><H3>How do I build gd?</H3></A>
@ -204,10 +226,10 @@ downloaded. If you are not familiar with <code>tar</code> and
consult with an experienced user of your system. Sorry, we cannot
answer questions about basic Internet skills.
<p>
Unpacking the archive will produce a directory called "gd1.3".
Unpacking the archive will produce a directory called "gd1.4".
<p>
<h4>For Unix</h4>
<code>cd</code> to the gd1.3 directory and examine the Makefile, which
<code>cd</code> to the gd1.4 directory and examine the Makefile, which
you will probably need to change slightly depending on your operating
system and your needs.
<h4>For Windows, Mac, Et Cetera</h4>
@ -424,6 +446,34 @@ A pointer to a <A HREF="#gdPoint">gdPoint</A> structure; passed
as an argument to <A HREF="#gdImagePolygon">gdImagePolygon</A>
and <A HREF="#gdImageFilledPolygon">gdImageFilledPolygon</A>.
</DL>
<DT><A NAME="gdSource">gdSource</A> <strong>(TYPE)</strong>
<DD>
<pre>
typedef struct {
int (*source) (void *context, char *buffer, int len);
void *context;
} gdSource, *gdSourcePtr;
</pre>
Represents a source from which a GIF can be read.
Programmers who do not wish to read GIFs from a file can provide
their own alternate input mechanism, using the
<a href="#gdImageCreateFromGifSource">gdImageCreateFromGifSource</a> function.
See the documentation of that function for an example of the
proper use of this type.
<DT><A NAME="gdSink">gdSink</A> <strong>(TYPE)</strong>
<DD>
<PRE>
typedef struct {
int (*sink) (void *context, char *buffer, int len);
void *context;
} gdSink, *gdSinkPtr;
</PRE>
Represents a "sink" (destination) to which a GIF can be written.
Programmers who do not wish to write GIFs to a file can provide
their own alternate output mechanism, using the
<a href="#gdImageGifToSink">gdImageGifToSink</a> function.
See the documentation of that function for an example of the
proper use of this type.
<H3><A NAME="creating">Image creation, destruction, loading and saving</A></H3>
<DL>
<DT><A NAME="gdImageCreate">gdImageCreate(sx, sy)</A>
@ -465,6 +515,46 @@ fclose(in);
/* ... Use the image ... */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
</PRE>
<DT><A NAME="gdImageCreateFromGifSource">gdImageCreateFromGifSource(gdSourcePtr in)</A>
<strong>(FUNCTION)</strong>
<dd>
gdImageCreateFromGifSource is called to load a GIF from
a data source other than a file. Usage is very similar to
the <a href="#gdImageCreateFromGif">gdImageCreateFromGif</a> function,
except that the programmer provides a custom data source.
<p>
The programmer must write an input function which accepts
a context pointer, a buffer, and a number of bytes to be
read as arguments. This function must read the number of
bytes requested, unless the end of the file has been reached,
in which case the function should return zero, or an error
has occurred, in which case the function should return
<code>-1</code>. The programmer then creates a
<a href="#gdSource">gdSource</a> structure and sets
the <code>source</code> pointer to the input function and
the context pointer to any value which is useful to the
programmer.
<p>
The example below
implements <a href="#gdImageCreateFromGif">gdImageCreateFromGif</a>
by creating a custom data source and invoking gdImageCreateFromGifSource.
<pre>
static int freadWrapper(void *context, char *buf, int len);
gdImagePtr gdImageCreateFromGif(FILE *in)
{
gdSource s;
s.source = freadWrapper;
s.context = in;
return gdImageCreateFromGifSource(&s);
}
static int freadWrapper(void *context, char *buf, int len)
{
int got = fread(buf, 1, len, (FILE *) context);
return got;
}
</pre>
<DT><A NAME="gdImageCreateFromGd">gdImageCreateFromGd(FILE *in)</A>
<strong>(FUNCTION)</strong>
<DD>
@ -532,9 +622,9 @@ void gdImageGif(gdImagePtr im, FILE *out)</A>
<STRONG>(FUNCTION)</STRONG>
<DD>
gdImageGif outputs the specified image to the specified
file in GIF format. The file must be open for writing. Under MSDOS,
it is important to use "wb" as opposed to simply "w"
as the mode when opening the file, and under Unix there
file in GIF format. The file must be open for writing. Under MSDOS
and all versions of Windows, it is important to use "wb" as opposed
to simply "w" as the mode when opening the file, and under Unix there
is no penalty for doing so. gdImageGif does <em>not</em>
close the file; your code must do so.
<PRE>
@ -559,13 +649,50 @@ fclose(out);
/* Destroy image */
<A HREF="#gdImageDestroy">gdImageDestroy</A>(im);
</PRE>
<DT><A NAME="gdImageGifToSink">gdImageGifToSink(gdImagePtr im, gdSinkPtr out)</A>
<strong>(FUNCTION)</strong>
<dd>
gdImageGifToSink is called to write a GIF to
a data "sink" (destination) other than a file. Usage is very similar to
the <a href="#gdImageGif">gdImageGif</a> function,
except that the programmer provides a custom data sink.
<p>
The programmer must write an output function which accepts
a context pointer, a buffer, and a number of bytes to be
written as arguments. This function must write the number of
bytes requested and return that number, unless an error
has occurred, in which case the function should return
<code>-1</code>. The programmer then creates a
<a href="#gdSink">gdSink</a> structure and sets
the <code>sink</code> pointer to the output function and
the context pointer to any value which is useful to the
programmer.
<p>
The example below
implements <a href="#gdImageGif">gdImageGif</a>
by creating a custom data source and invoking gdImageGifFromSink.
<pre>
static int stdioSink(void *context, char *buffer, int len)
{
return fwrite(buffer, 1, len, (FILE *) context);
}
void gdImageGif(gdImagePtr im, FILE *out)
{
gdSink mySink;
mySink.context = (void *) out;
mySink.sink = stdioSink;
gdImageGifToSink(im, &mySink);
}
</pre>
<DT><A NAME="gdImageGd">
void gdImageGd(gdImagePtr im, FILE *out)</A>
<STRONG>(FUNCTION)</STRONG>
<DD>
gdImageGd outputs the specified image to the specified
file in the <A HREF="#gdformat">gd image format</A>. The file must
be open for writing. Under MSDOS, it is important to use "wb" as
be open for writing. Under MSDOS and all versions of Windows, it is
important to use "wb" as
opposed to simply "w" as the mode when opening the file, and under
Unix there is no penalty for doing so. gdImageGif does <em>not</em>
close the file; your code must do so.
@ -827,8 +954,8 @@ 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
a problem in MSDOS and MS Windows 3.1 environments. (Of course,
in a Unix or Windows 95/98/NT environment with a proper stack, this is
not a problem at all.)
<PRE>
... inside a function ...
@ -875,7 +1002,7 @@ 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
in a Unix or Windows 95/98/NT environment with a proper stack, this is
not a problem at all.)
<PRE>
... inside a function ...
@ -1933,6 +2060,7 @@ Be sure to read this manual carefully first.
<A HREF="#gdImageCreate">gdImageCreate</A> |
<A HREF="#gdImageCreateFromGd">gdImageCreateFromGd</A> |
<A HREF="#gdImageCreateFromGif">gdImageCreateFromGif</A> |
<A HREF="#gdImageCreateFromGifSource">gdImageCreateFromGifSource</A> |
<A HREF="#gdImageCreateFromXbm">gdImageCreateFromXbm</A> |
<A HREF="#gdImageDashedLine">gdImageDashedLine</A> |
<A HREF="#gdImageDestroy">gdImageDestroy</A> |
@ -1944,6 +2072,7 @@ Be sure to read this manual carefully first.
<A HREF="#gdImageGetPixel">gdImageGetPixel</A> |
<A HREF="#gdImageGetTransparent">gdImageGetTransparent</A> |
<A HREF="#gdImageGif">gdImageGif</A> |
<A HREF="#gdImageGifToSink">gdImageGifToSink</A> |
<A HREF="#gdImageGreen">gdImageGreen</A> |
<A HREF="#gdImageInterlace">gdImageInterlace</A> |
<A HREF="#gdImageLine">gdImageLine</A> |

432
src/readme.txt
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@ -1,8 +1,10 @@
SEE INDEX.HTML FOR AN EASILY BROWSED HYPERTEXT VERSION OF THIS MANUAL.
SEE index.html FOR A MUCH MORE USEFUL HYPERTEXT VERSION OF THIS DOCUMENT!
SEE index.html FOR A MUCH MORE USEFUL HYPERTEXT VERSION OF THIS DOCUMENT!
SEE index.html FOR A MUCH MORE USEFUL HYPERTEXT VERSION OF THIS DOCUMENT!
SEE index.html FOR A MUCH MORE USEFUL HYPERTEXT VERSION OF THIS DOCUMENT!
SEE index.html FOR A MUCH MORE USEFUL HYPERTEXT VERSION OF THIS DOCUMENT!
* * *
gd 1.3
gd 1.4
A graphics library for fast GIF creation
@ -11,7 +13,7 @@ Follow this link to the latest version of this document.
Table of Contents
* Credits and license terms
* What's new in version 1.3?
* What's new in version 1.4?
* What is gd?
* What if I want to use another programming language?
* What else do I need to use gd?
@ -31,12 +33,12 @@ Follow this link to the latest version of this document.
In order to resolve any possible confusion regarding the authorship of
gd, the following copyright statement covers all of the authors who
have required such a statement. Although his LZW compression code no
have required such a statement. _Although his LZW compression code no
longer appears in gd, the authors wish to thank David Rowley for the
original LZW-based GIF compression code, which has been removed due to
patent concerns. If you are aware of any oversights in this copyright
notice, please contact Thomas Boutell who will be pleased to correct
them.
patent concerns._ _If you are aware of any oversights in this
copyright notice, please contact Thomas Boutell who will be pleased to
correct them._
COPYRIGHT STATEMENT FOLLOWS THIS LINE
@ -52,9 +54,9 @@ COPYRIGHT STATEMENT FOLLOWS THIS LINE
Non-LZW-based GIF compression code copyright 1998, by Hutchison
Avenue Software Corporation (http://www.hasc.com/, info@hasc.com).
Permission has been granted to copy and distribute gd in any
_Permission has been granted to copy and distribute gd in any
context, including a commercial application, provided that this
notice is present in user-accessible supporting documentation.
notice is present in user-accessible supporting documentation._
This does not affect your ownership of the derived work itself, and
the intent is to assure proper credit for the authors of gd, not to
@ -107,10 +109,34 @@ END OF COPYRIGHT STATEMENT
invoke the interpreter.
These packages are based on gd 1.2 as of this writing but should be
compatible with gd 1.3 with minimal tweaking.
compatible with gd 1.3x with minimal tweaking.
* tgd, by Bradley K. Sherman
* fly, by Martin Gleeson
What's new in version 1.4?
Version 1.4 features the following changes:
Fixed polygon fill routine (again)
Thanks to Kirsten Schulz, version 1.4 is able to fill numerous
types of polygons that caused problems with previous releases,
including version 1.3.
Support for alternate data sources
Programmers who wish to load a GIF from something other than a
stdio FILE * stream can use the new gdImageCreateFromGifSource
function.
Support for alternate data destinations
Programmers who wish to write a GIF to something other than a
stdio FILE * stream can use the new gdImageGifToSink function.
More tolerant when reading GIFs
Version 1.4 does not crash when reading certain animated GIFs,
although it still only reads the first frame. Version 1.4 also
has overflow testing code to prevent crashes when reading
damaged GIFs.
What's new in version 1.3?
Version 1.3 features the following changes:
@ -119,13 +145,13 @@ END OF COPYRIGHT STATEMENT
Version 1.3 contains GIF compression code that uses simple Run
Length Encoding instead of LZW compression, while still
retaining compatibility with normal LZW-based GIF decoders
(your browser will still like your GIFs). LZW compression is
(your browser will still like your GIFs). _LZW compression is
patented by Unisys. This is why there have been no new versions
of gd for a long time. THANKS to Hutchison Avenue Software
Corporation for contributing this code. THE NEW CODE PRODUCES
LARGER GIFS AND IS NOT WELL SUITED TO PHOTOGRAPHIC IMAGES. THIS
IS A LEGAL ISSUE. IT IS NOT A QUESTION OF TECHNICAL SKILL.
PLEASE DON'T COMPLAIN ABOUT THE SIZE OF GIF OUTPUT. THANKS!
PLEASE DON'T COMPLAIN ABOUT THE SIZE OF GIF OUTPUT. THANKS!_
8-bit fonts, and 8-bit font support
This improves support for European languages. Thanks are due to
@ -149,26 +175,26 @@ END OF COPYRIGHT STATEMENT
A one-line patch for the infamous polygon fill bug, courtesy of
Jim Mason. I believe this fix is sufficient. However, if you
find a situation where polygon fills still fail to behave
properly, please send code that demonstrates the problem, and a
fix if you have one. Verifying the fix is important.
properly, please send code that demonstrates the problem, _and_
a fix if you have one. Verifying the fix is important.
Row-major, not column-major
Internally, gd now represents the array of pixels as an array
of rows of pixels, rather than an array of columns of pixels.
This improves the performance of compression and decompression
routines slightly, because horizontally adjacent pixels are now
next to each other in memory. This should not affect properly
next to each other in memory. _This should not affect properly
written gd applications, but applications that directly
manipulate the pixels array will require changes.
manipulate the pixels array will require changes._
What else do I need to use gd?
To use gd, you will need an ANSI C compiler. All popular Windows 95
and NT C compilers are ANSI C compliant. Any full-ANSI-standard C
compiler should be adequate. The cc compiler released with SunOS 4.1.3
is not an ANSI C compiler. Most Unix users who do not already have gcc
should get it. gcc is free, ANSI compliant and a de facto industry
standard. Ask your ISP why it is missing.
To use gd, you will need an ANSI C compiler. _All popular Windows 95
and NT C compilers are ANSI C compliant._ Any full-ANSI-standard C
compiler should be adequate. _The cc compiler released with SunOS
4.1.3 is not an ANSI C compiler. Most Unix users who do not already
have gcc should get it. gcc is free, ANSI compliant and a de facto
industry standard. Ask your ISP why it is missing._
You will also want a GIF viewer, if you do not already have one for
your system, since you will need a good way to check the results of
@ -196,11 +222,11 @@ END OF COPYRIGHT STATEMENT
(Windows), please consult with an experienced user of your system.
Sorry, we cannot answer questions about basic Internet skills.
Unpacking the archive will produce a directory called "gd1.3".
Unpacking the archive will produce a directory called "gd1.4".
For Unix
cd to the gd1.3 directory and examine the Makefile, which you will
cd to the gd1.4 directory and examine the Makefile, which you will
probably need to change slightly depending on your operating system
and your needs.
@ -249,9 +275,9 @@ END OF COPYRIGHT STATEMENT
the source modules as well in your project. (They may be too large for
16-bit memory models, that is, 16-bit DOS and Windows.)
Here is a short example program. (For a more advanced example, see
Here is a short example program. _(For a more advanced example, see
gddemo.c, included in the distribution. gddemo.c is NOT the same
program; it demonstrates additional features!)
program; it demonstrates additional features!)_
/* Bring in gd library functions */
#include "gd.h"
@ -333,7 +359,7 @@ Function and type reference
Types
gdImage(TYPE)
gdImage_(TYPE)_
The data structure in which gd stores images. gdImageCreate
returns a pointer to this type, and the other functions expect
to receive a pointer to this type as their first argument. You
@ -358,11 +384,11 @@ typedef struct {
int transparent;
} gdImage;
gdImagePtr (TYPE)
gdImagePtr _(TYPE)_
A pointer to an image structure. gdImageCreate returns this
type, and the other functions expect it as the first argument.
gdFont (TYPE)
gdFont _(TYPE)_
A font structure. Used to declare the characteristics of a
font. Plese see the files gdfontl.c and gdfontl.h for an
example of the proper declaration of this structure. You can
@ -388,13 +414,13 @@ typedef struct {
char *data;
} gdFont;
gdFontPtr (TYPE)
gdFontPtr _(TYPE)_
A pointer to a font structure. Text-output functions expect
these as their second argument, following the gdImagePtr
argument. Two such pointers are declared in the provided
include files gdfonts.h and gdfontl.h.
gdPoint (TYPE)
gdPoint _(TYPE)_
Represents a point in the coordinate space of the image; used
by gdImagePolygon and gdImageFilledPolygon.
@ -403,13 +429,39 @@ typedef struct {
int x, y;
} gdPoint, *gdPointPtr;
gdPointPtr (TYPE)
gdPointPtr _(TYPE)_
A pointer to a gdPoint structure; passed as an argument to
gdImagePolygon and gdImageFilledPolygon.
gdSource _(TYPE)_
typedef struct {
int (*source) (void *context, char *buffer, int len);
void *context;
} gdSource, *gdSourcePtr;
Represents a source from which a GIF can be read. Programmers who do
not wish to read GIFs from a file can provide their own alternate
input mechanism, using the gdImageCreateFromGifSource function. See
the documentation of that function for an example of the proper use of
this type.
gdSink _(TYPE)_
typedef struct {
int (*sink) (void *context, char *buffer, int len);
void *context;
} gdSink, *gdSinkPtr;
Represents a "sink" (destination) to which a GIF can be written.
Programmers who do not wish to write GIFs to a file can provide their
own alternate output mechanism, using the gdImageGifToSink function.
See the documentation of that function for an example of the proper
use of this type.
Image creation, destruction, loading and saving
gdImageCreate(sx, sy) (FUNCTION)
gdImageCreate(sx, sy) _(FUNCTION)_
gdImageCreate is called to create images. Invoke gdImageCreate
with the x and y dimensions of the desired image. gdImageCreate
returns a gdImagePtr to the new image, or NULL if unable to
@ -423,14 +475,14 @@ im = gdImageCreate(64, 64);
/* ... Use the image ... */
gdImageDestroy(im);
gdImageCreateFromGif(FILE *in) (FUNCTION)
gdImageCreateFromGif(FILE *in) _(FUNCTION)_
gdImageCreateFromGif is called to load images from GIF format
files. Invoke gdImageCreateFromGif with an already opened
pointer to a file containing the desired image.
gdImageCreateFromGif returns a gdImagePtr to the new image, or
NULL if unable to load the image (most often because the file
is corrupt or does not contain a GIF image).
gdImageCreateFromGif does not close the file. You can inspect
gdImageCreateFromGif does _not_ close the file. You can inspect
the sx and sy members of the image to determine its size. The
image must eventually be destroyed using gdImageDestroy().
@ -444,18 +496,55 @@ fclose(in);
/* ... Use the image ... */
gdImageDestroy(im);
gdImageCreateFromGd(FILE *in) (FUNCTION)
gdImageCreateFromGifSource(gdSourcePtr in) _(FUNCTION)_
gdImageCreateFromGifSource is called to load a GIF from a data
source other than a file. Usage is very similar to the
gdImageCreateFromGif function, except that the programmer
provides a custom data source.
The programmer must write an input function which accepts a
context pointer, a buffer, and a number of bytes to be read as
arguments. This function must read the number of bytes
requested, unless the end of the file has been reached, in
which case the function should return zero, or an error has
occurred, in which case the function should return -1. The
programmer then creates a gdSource structure and sets the
source pointer to the input function and the context pointer to
any value which is useful to the programmer.
The example below implements gdImageCreateFromGif by creating a
custom data source and invoking gdImageCreateFromGifSource.
static int freadWrapper(void *context, char *buf, int len);
gdImagePtr gdImageCreateFromGif(FILE *in)
{
gdSource s;
s.source = freadWrapper;
s.context = in;
return gdImageCreateFromGifSource(&s);
}
static int freadWrapper(void *context, char *buf, int len)
{
int got = fread(buf, 1, len, (FILE *) context);
return got;
}
gdImageCreateFromGd(FILE *in) _(FUNCTION)_
gdImageCreateFromGd is called to load images from gd format
files. Invoke gdImageCreateFromGd with an already opened
pointer to a file containing the desired image in the gd file
format, which is specific to gd and intended for very fast
loading. (It is not intended for compression; for compression,
use GIF.) gdImageCreateFromGd returns a gdImagePtr to the new
image, or NULL if unable to load the image (most often because
the file is corrupt or does not contain a gd format image).
gdImageCreateFromGd does not close the file. You can inspect
the sx and sy members of the image to determine its size. The
image must eventually be destroyed using gdImageDestroy().
loading. (It is _not_ intended for compression; for
compression, use GIF.) gdImageCreateFromGd returns a gdImagePtr
to the new image, or NULL if unable to load the image (most
often because the file is corrupt or does not contain a gd
format image). gdImageCreateFromGd does _not_ close the file.
You can inspect the sx and sy members of the image to determine
its size. The image must eventually be destroyed using
gdImageDestroy().
... inside a function ...
@ -467,14 +556,14 @@ fclose(in);
/* ... Use the image ... */
gdImageDestroy(im);
gdImageCreateFromXbm(FILE *in) (FUNCTION)
gdImageCreateFromXbm(FILE *in) _(FUNCTION)_
gdImageCreateFromXbm is called to load images from X bitmap
format files. Invoke gdImageCreateFromXbm with an already
opened pointer to a file containing the desired image.
gdImageCreateFromXbm returns a gdImagePtr to the new image, or
NULL if unable to load the image (most often because the file
is corrupt or does not contain an X bitmap format image).
gdImageCreateFromXbm does not close the file. You can inspect
gdImageCreateFromXbm does _not_ close the file. You can inspect
the sx and sy members of the image to determine its size. The
image must eventually be destroyed using gdImageDestroy().
@ -488,7 +577,7 @@ fclose(in);
/* ... Use the image ... */
gdImageDestroy(im);
gdImageDestroy(gdImagePtr im) (FUNCTION)
gdImageDestroy(gdImagePtr im) _(FUNCTION)_
gdImageDestroy is used to free the memory associated with an
image. It is important to invoke gdImageDestroy before exiting
your program or assigning a new image to a gdImagePtr variable.
@ -501,13 +590,13 @@ im = gdImageCreate(10, 10);
/* Now destroy it */
gdImageDestroy(im);
void gdImageGif(gdImagePtr im, FILE *out) (FUNCTION)
void gdImageGif(gdImagePtr im, FILE *out) _(FUNCTION)_
gdImageGif outputs the specified image to the specified file in
GIF format. The file must be open for writing. Under MSDOS, it
is important to use "wb" as opposed to simply "w" as the mode
when opening the file, and under Unix there is no penalty for
doing so. gdImageGif does not close the file; your code must do
so.
GIF format. The file must be open for writing. Under MSDOS and
all versions of Windows, it is important to use "wb" as opposed
to simply "w" as the mode when opening the file, and under Unix
there is no penalty for doing so. gdImageGif does _not_ close
the file; your code must do so.
... inside a function ...
@ -531,18 +620,50 @@ fclose(out);
/* Destroy image */
gdImageDestroy(im);
void gdImageGd(gdImagePtr im, FILE *out) (FUNCTION)
gdImageGifToSink(gdImagePtr im, gdSinkPtr out) _(FUNCTION)_
gdImageGifToSink is called to write a GIF to a data "sink"
(destination) other than a file. Usage is very similar to the
gdImageGif function, except that the programmer provides a
custom data sink.
The programmer must write an output function which accepts a
context pointer, a buffer, and a number of bytes to be written
as arguments. This function must write the number of bytes
requested and return that number, unless an error has occurred,
in which case the function should return -1. The programmer
then creates a gdSink structure and sets the sink pointer to
the output function and the context pointer to any value which
is useful to the programmer.
The example below implements gdImageGif by creating a custom
data source and invoking gdImageGifFromSink.
static int stdioSink(void *context, char *buffer, int len)
{
return fwrite(buffer, 1, len, (FILE *) context);
}
void gdImageGif(gdImagePtr im, FILE *out)
{
gdSink mySink;
mySink.context = (void *) out;
mySink.sink = stdioSink;
gdImageGifToSink(im, &mySink);
}
void gdImageGd(gdImagePtr im, FILE *out) _(FUNCTION)_
gdImageGd outputs the specified image to the specified file in
the gd image format. The file must be open for writing. Under
MSDOS, it is important to use "wb" as opposed to simply "w" as
the mode when opening the file, and under Unix there is no
penalty for doing so. gdImageGif does not close the file; your
code must do so.
MSDOS and all versions of Windows, it is important to use "wb"
as opposed to simply "w" as the mode when opening the file, and
under Unix there is no penalty for doing so. gdImageGif does
_not_ close the file; your code must do so.
The gd image format is intended for fast reads and writes of
images your program will need frequently to build other images.
It is not a compressed format, and is not intended for general
use.
It is _not_ a compressed format, and is not intended for
general use.
... inside a function ...
@ -569,7 +690,7 @@ gdImageDestroy(im);
Drawing Functions
void gdImageSetPixel(gdImagePtr im, int x, int y, int color)
(FUNCTION)
_(FUNCTION)_
gdImageSetPixel sets a pixel to a particular color index.
Always use this function or one of the other drawing functions
to access pixels; do not access the pixels of the gdImage
@ -592,7 +713,7 @@ gdImageSetPixel(im, 50, 50, white);
gdImageDestroy(im);
void gdImageLine(gdImagePtr im, int x1, int y1, int x2, int y2, int
color) (FUNCTION)
color) _(FUNCTION)_
gdImageLine is used to draw a line between two endpoints (x1,y1
and x2, y2). The line is drawn using the color index specified.
Note that the color index can be an actual color returned by
@ -616,9 +737,9 @@ gdImageLine(im, 0, 0, 99, 99, white);
gdImageDestroy(im);
void gdImageDashedLine(gdImagePtr im, int x1, int y1, int x2, int y2,
int color) (FUNCTION)
gdImageDashedLine is provided solely for backwards
compatibility with gd 1.0. New programs should draw dashed
int color) _(FUNCTION)_
gdImageDashedLine is provided _solely for backwards
compatibility _with gd 1.0. New programs should draw dashed
lines using the normal gdImageLine function and the new
gdImageSetStyle function.
@ -644,7 +765,7 @@ gdImageDashedLine(im, 0, 0, 99, 99);
gdImageDestroy(im);
void gdImagePolygon(gdImagePtr im, gdPointPtr points, int pointsTotal,
int color) (FUNCTION)
int color) _(FUNCTION)_
gdImagePolygon is used to draw a polygon with the verticies (at
least 3) specified, using the color index specified. See also
gdImageFilledPolygon.
@ -674,7 +795,7 @@ gdImagePolygon(im, points, 3, white);
gdImageDestroy(im);
void gdImageRectangle(gdImagePtr im, int x1, int y1, int x2, int y2,
int color) (FUNCTION)
int color) _(FUNCTION)_
gdImageRectangle is used to draw a rectangle with the two
corners (upper left first, then lower right) specified, using
the color index specified.
@ -696,7 +817,7 @@ gdImageRectangle(im, 25, 25, 74, 74, white);
gdImageDestroy(im);
void gdImageFilledPolygon(gdImagePtr im, gdPointPtr points, int
pointsTotal, int color) (FUNCTION)
pointsTotal, int color) _(FUNCTION)_
gdImageFilledPolygon is used to fill a polygon with the
verticies (at least 3) specified, using the color index
specified. See also gdImagePolygon.
@ -732,7 +853,7 @@ gdImagePolygon(im, points, 3, red);
gdImageDestroy(im);
void gdImageFilledRectangle(gdImagePtr im, int x1, int y1, int x2, int
y2, int color) (FUNCTION)
y2, int color) _(FUNCTION)_
gdImageFilledRectangle is used to draw a solid rectangle with
the two corners (upper left first, then lower right) specified,
using the color index specified.
@ -754,7 +875,7 @@ gdImageFilledRectangle(im, 25, 25, 74, 74, white);
gdImageDestroy(im);
void gdImageArc(gdImagePtr im, int cx, int cy, int w, int h, int s,
int e, int color) (FUNCTION)
int e, int color) _(FUNCTION)_
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 s and ends
@ -781,22 +902,23 @@ gdImageArc(im, 50, 25, 98, 48, 0, 360, white);
gdImageDestroy(im);
void gdImageFillToBorder(gdImagePtr im, int x, int y, int border, int
color) (FUNCTION)
color) _(FUNCTION)_
gdImageFillToBorder floods a portion of the image with the
specified color, beginning at the specified point and stopping
at the specified border color. For a way of flooding an area
defined by the color of the starting point, see gdImageFill.
The border color cannot be a special color such as gdTiled; it
must be a proper solid color. The fill color can be, however.
The border color _cannot_ be a special color such as gdTiled;
it must be a proper solid color. The fill color can be,
however.
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.)
in MSDOS and MS Windows 3.1 environments. (Of course, in a Unix
or Windows 95/98/NT environment with a proper stack, this is
not a problem at all.)
... inside a function ...
@ -820,7 +942,7 @@ gdImageFillToBorder(im, 50, 50, white, red);
/* Destroy it */
gdImageDestroy(im);
void gdImageFill(gdImagePtr im, int x, int y, int color) (FUNCTION)
void gdImageFill(gdImagePtr im, int x, int y, int color) _(FUNCTION)_
gdImageFill floods a portion of the image with the specified
color, beginning at the specified point and flooding the
surrounding region of the same color as the starting point. For
@ -838,8 +960,9 @@ gdImageDestroy(im);
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.)
MS Windows environments. (Of course, in a Unix or Windows
95/98/NT environment with a proper stack, this is not a problem
at all.)
... inside a function ...
@ -863,10 +986,10 @@ gdImageFill(im, 50, 50, red);
/* Destroy it */
gdImageDestroy(im);
void gdImageSetBrush(gdImagePtr im, gdImagePtr brush) (FUNCTION)
void gdImageSetBrush(gdImagePtr im, gdImagePtr brush) _(FUNCTION)_
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. Any gd image can be
brush image need not be a single pixel. _Any_ gd image can be
used as a brush, and by setting the transparent color index of
the brush image with gdImageColorTransparent, a brush of any
shape can be created. All line-drawing functions, such as
@ -916,10 +1039,10 @@ gdImageDestroy(im);
/* Destroy the brush image */
gdImageDestroy(brush);
void gdImageSetTile(gdImagePtr im, gdImagePtr tile) (FUNCTION)
void gdImageSetTile(gdImagePtr im, gdImagePtr tile) _(FUNCTION)_
A "tile" is an image used to fill an area with a repeated
pattern. Any gd image can be used as a tile, and by setting the
transparent color index of the tile image with
pattern. _Any_ gd image can be used as a tile, and by setting
the transparent color index of the tile image with
gdImageColorTransparent, a tile that allows certain parts of
the underlying area to shine through can be created. All
region-filling functions, such as gdImageFill and
@ -968,7 +1091,7 @@ gdImageDestroy(im);
gdImageDestroy(tile);
void gdImageSetStyle(gdImagePtr im, int *style, int styleLength)
(FUNCTION)
_(FUNCTION)_
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
@ -1036,12 +1159,12 @@ gdImageDestroy(im);
Query Functions
int gdImageBlue(gdImagePtr im, int color) (MACRO)
int gdImageBlue(gdImagePtr im, int color) _(MACRO)_
gdImageBlue is a macro which returns the blue component
of the specified color index. Use this macro rather than
accessing the structure members directly.
int gdImageGetPixel(gdImagePtr im, int x, int y) (FUNCTION)
int gdImageGetPixel(gdImagePtr im, int x, int y) _(FUNCTION)_
gdImageGetPixel() retrieves the color index of a
particular pixel. Always use this function to query
pixels; do not access the pixels of the gdImage structure
@ -1060,7 +1183,7 @@ printf("The value of the center pixel is %d; RGB values are %d,%d,%d\n",
c, im->red[c], im->green[c], im->blue[c]);
gdImageDestroy(im);
int gdImageBoundsSafe(gdImagePtr im, int x, int y) (FUNCTION)
int gdImageBoundsSafe(gdImagePtr im, int x, int y) _(FUNCTION)_
gdImageBoundsSafe returns true (1) if the specified point
is within the bounds of the image, false (0) if not. This
function is intended primarily for use by those who wish
@ -1080,22 +1203,22 @@ if (gdImageBoundsSafe(im, 50, 50)) {
}
gdImageDestroy(im);
int gdImageGreen(gdImagePtr im, int color) (MACRO)
int gdImageGreen(gdImagePtr im, int color) _(MACRO)_
gdImageGreen is a macro which returns the green component
of the specified color index. Use this macro rather than
accessing the structure members directly.
int gdImageRed(gdImagePtr im, int color) (MACRO)
int gdImageRed(gdImagePtr im, int color) _(MACRO)_
gdImageRed is a macro which returns the red component of
the specified color index. Use this macro rather than
accessing the structure members directly.
int gdImageSX(gdImagePtr im) (MACRO)
int gdImageSX(gdImagePtr im) _(MACRO)_
gdImageSX is a macro which returns the width of the image
in pixels. Use this macro rather than accessing the
structure members directly.
int gdImageSY(gdImagePtr im) (MACRO)
int gdImageSY(gdImagePtr im) _(MACRO)_
gdImageSY is a macro which returns the height of the
image in pixels. Use this macro rather than accessing the
structure members directly.
@ -1103,7 +1226,7 @@ gdImageDestroy(im);
Fonts and text-handling functions
void gdImageChar(gdImagePtr im, gdFontPtr font, int x, int y, int
c, int color) (FUNCTION)
c, int color) _(FUNCTION)_
gdImageChar is used to draw single characters on the
image. (To draw multiple characters, use gdImageString or
gdImageString16.) The second argument is a pointer to a
@ -1138,7 +1261,7 @@ gdImageChar(im, gdFontLarge, 0, 0, 'Q', white);
gdImageDestroy(im);
void gdImageCharUp(gdImagePtr im, gdFontPtr font, int x, int y,
int c, int color) (FUNCTION)
int c, int color) _(FUNCTION)_
gdImageCharUp is used to draw single characters on the
image, rotated 90 degrees. (To draw multiple characters,
use gdImageStringUp or gdImageStringUp16.) The second
@ -1175,7 +1298,7 @@ gdImageCharUp(im, gdFontLarge,
gdImageDestroy(im);
void gdImageString(gdImagePtr im, gdFontPtr font, int x, int y,
unsigned char *s, int color) (FUNCTION)
unsigned char *s, int color) _(FUNCTION)_
gdImageString is used to draw multiple characters on the
image. (To draw single characters, use gdImageChar.) The
second argument is a pointer to a font definition
@ -1216,7 +1339,7 @@ gdImageString(im, gdFontLarge,
gdImageDestroy(im);
void gdImageString16(gdImagePtr im, gdFontPtr font, int x, int y,
unsigned short *s, int color) (FUNCTION)
unsigned short *s, int color) _(FUNCTION)_
gdImageString is used to draw multiple 16-bit characters
on the image. (To draw single characters, use
gdImageChar.) The second argument is a pointer to a font
@ -1239,7 +1362,7 @@ gdImageDestroy(im);
gdImageString.
void gdImageStringUp(gdImagePtr im, gdFontPtr font, int x, int y,
unsigned char *s, int color) (FUNCTION)
unsigned char *s, int color) _(FUNCTION)_
gdImageStringUp is used to draw multiple characters on
the image, rotated 90 degrees. (To draw single
characters, use gdImageCharUp.) The second argument is a
@ -1282,7 +1405,7 @@ gdImageStringUp(im, gdFontLarge,
gdImageDestroy(im);
void gdImageStringUp16(gdImagePtr im, gdFontPtr font, int x, int
y, unsigned short *s, int color) (FUNCTION)
y, unsigned short *s, int color) _(FUNCTION)_
gdImageString is used to draw multiple 16-bit characters
vertically on the image. (To draw single characters, use
gdImageChar.) The second argument is a pointer to a font
@ -1307,7 +1430,7 @@ gdImageDestroy(im);
Color-handling functions
int gdImageColorAllocate(gdImagePtr im, int r, int g, int b)
(FUNCTION)
_(FUNCTION)_
gdImageColorAllocate finds the first available color
index in the image specified, sets its RGB values to
those requested (255 is the maximum for each), and
@ -1343,7 +1466,7 @@ gdImageDashedLine(im, 0, 0, 99, 99, red);
gdImageDestroy(im);
int gdImageColorClosest(gdImagePtr im, int r, int g, int b)
(FUNCTION)
_(FUNCTION)_
gdImageColorClosest searches the colors which have been
defined thus far in the image specified and returns the
index of the color with RGB values closest to those of
@ -1376,7 +1499,7 @@ fclose(in);
red = gdImageColorAllocate(im, 255, 0, 0);
/* If we fail to allocate red... */
if (red == (-1)) {
/* Find the closest color instead. */
/* Find the _closest_ color instead. */
red = gdImageColorClosest(im, 255, 0, 0);
}
/* Draw a dashed line from the upper left corner to the lower right corner */
@ -1386,7 +1509,7 @@ gdImageDashedLine(im, 0, 0, 99, 99, red);
gdImageDestroy(im);
int gdImageColorExact(gdImagePtr im, int r, int g, int b)
(FUNCTION)
_(FUNCTION)_
gdImageColorExact searches the colors which have been
defined thus far in the image specified and returns the
index of the first color with RGB values which exactly
@ -1410,7 +1533,7 @@ red = gdImageColorExact(im, 255, 0, 0);
if (red == (-1)) {
/* Second best: try to allocate it directly. */
red = gdImageColorAllocate(im, 255, 0, 0);
/* Out of colors, so find the closest color instead. */
/* Out of colors, so find the _closest_ color instead. */
red = gdImageColorClosest(im, 255, 0, 0);
}
/* Draw a dashed line from the upper left corner to the lower right corner */
@ -1419,45 +1542,46 @@ gdImageDashedLine(im, 0, 0, 99, 99, red);
/* Destroy it */
gdImageDestroy(im);
int gdImageColorsTotal(gdImagePtr im) (MACRO)
int gdImageColorsTotal(gdImagePtr im) _(MACRO)_
gdImageColorsTotal is a macro which returns the number of
colors currently allocated in the image. Use this macro
to obtain this information; do not access the structure
directly.
int gdImageColorRed(gdImagePtr im, int c) (MACRO)
int gdImageColorRed(gdImagePtr im, int c) _(MACRO)_
gdImageColorRed is a macro which returns the red portion
of the specified color in the image. Use this macro to
obtain this information; do not access the structure
directly.
int gdImageColorGreen(gdImagePtr im, int c) (MACRO)
int gdImageColorGreen(gdImagePtr im, int c) _(MACRO)_
gdImageColorGreen is a macro which returns the green
portion of the specified color in the image. Use this
macro to obtain this information; do not access the
structure directly.
int gdImageColorBlue(gdImagePtr im, int c) (MACRO)
int gdImageColorBlue(gdImagePtr im, int c) _(MACRO)_
gdImageColorBlue is a macro which returns the green
portion of the specified color in the image. Use this
macro to obtain this information; do not access the
structure directly.
int gdImageGetInterlaced(gdImagePtr im) (MACRO)
int gdImageGetInterlaced(gdImagePtr im) _(MACRO)_
gdImageGetInterlaced is a macro which returns true (1) if
the image is interlaced, false (0) if not. Use this macro
to obtain this information; do not access the structure
directly. See gdImageInterlace for a means of interlacing
images.
int gdImageGetTransparent(gdImagePtr im) (MACRO)
int gdImageGetTransparent(gdImagePtr im) _(MACRO)_
gdImageGetTransparent is a macro which returns the
current transparent color index in the image. If there is
no transparent color, gdImageGetTransparent returns -1.
Use this macro to obtain this information; do not access
the structure directly.
void gdImageColorDeallocate(gdImagePtr im, int color) (FUNCTION)
void gdImageColorDeallocate(gdImagePtr im, int color) _(FUNCTION)_
gdImageColorDeallocate marks the specified color as being
available for reuse. It does not attempt to determine
whether the color index is still in use in the image.
@ -1490,11 +1614,11 @@ if (red != (-1)) {
/* Destroy it */
gdImageDestroy(im);
void gdImageColorTransparent(gdImagePtr im, int color) (FUNCTION)
void gdImageColorTransparent(gdImagePtr im, int color)
_(FUNCTION)_
gdImageColorTransparent sets the transparent color index
for the specified image to the specified index. To
indicate that there should be no transparent color,
indicate that there should be _no_ transparent color,
invoke gdImageColorTransparent with a color index of -1.
The color index used should be an index allocated by
@ -1504,8 +1628,8 @@ gdImageDestroy(im);
when viewed by users who do not have transparent
background capabilities, be sure to give reasonable RGB
values to the color you allocate for use as a transparent
color, even though it will be transparent on systems that
support transparency.
color, _even though it will be transparent on systems
that support transparency_.
... inside a function ...
@ -1532,7 +1656,7 @@ gdImageDestroy(im);
Copying and resizing functions
void gdImageCopy(gdImagePtr dst, gdImagePtr src, int dstX, int
dstY, int srcX, int srcY, int w, int h) (FUNCTION)
dstY, int srcX, int srcY, int w, int h) _(FUNCTION)_
gdImageCopy is used to copy a rectangular portion of one
image to another image. (For a way of stretching or
shrinking the image in the process, see
@ -1552,10 +1676,10 @@ gdImageDestroy(im);
perform as expected unless the regions overlap, in which
case the result is unpredictable.
Important note on copying between images: since different
images do not necessarily have the same color tables,
pixels are not simply set to the same color index values
to copy them. gdImageCopy will attempt to find an
_Important note on copying between images:_ since
different images do not necessarily have the same color
tables, pixels are not simply set to the same color index
values to copy them. gdImageCopy will attempt to find an
identical RGB value in the destination image for each
pixel in the copied portion of the source image by
invoking gdImageColorExact. If such a value is not found,
@ -1595,7 +1719,7 @@ gdImageDestroy(im_out);
void gdImageCopyResized(gdImagePtr dst, gdImagePtr src, int dstX,
int dstY, int srcX, int srcY, int destW, int destH, int
srcW, int srcH) (FUNCTION)
srcW, int srcH) _(FUNCTION)_
gdImageCopyResized is used to copy a rectangular portion
of one image to another image. The X and Y dimensions of
the original region and the destination region can vary,
@ -1622,8 +1746,8 @@ gdImageDestroy(im_out);
problem, create a scratch image in which to keep
intermediate results.
Important note on copying between images: since images do
not necessarily have the same color tables, pixels are
_Important note on copying between images:_ since images
do not necessarily have the same color tables, pixels are
not simply set to the same color index values to copy
them. gdImageCopy will attempt to find an identical RGB
value in the destination image for each pixel in the
@ -1660,7 +1784,8 @@ gdImageDestroy(im_out);
Miscellaneous Functions
gdImageInterlace(gdImagePtr im, int interlace) (FUNCTION)
gdImageInterlace(gdImagePtr im, int interlace) _(FUNCTION)_
gdImageInterlace is used to determine whether an
image should be stored in a linear fashion, in
which lines will appear on the display from first
@ -1678,7 +1803,7 @@ gdImageDestroy(im_out);
interlace will be set according to the setting in
the GIF file.
Note that many GIF viewers and web browsers do not
Note that many GIF viewers and web browsers do _not_
support interlace. However, the interlaced GIF
should still display; it will simply appear all at
once, just as other images do.
@ -1699,7 +1824,7 @@ gdImageDestroy(im);
Constants
gdBrushed (CONSTANT)
gdBrushed _(CONSTANT)_
Used in place of a color when invoking a
line-drawing function such as gdImageLine or
gdImageRectangle. When gdBrushed is used as the
@ -1710,13 +1835,13 @@ gdImageDestroy(im);
gdStyledBrushed for a way to draw broken lines with
a series of distinct copies of an image.
gdMaxColors(CONSTANT)
gdMaxColors_(CONSTANT)_
The constant 256. This is the maximum number of
colors in a GIF file according to the GIF standard,
and is also the maximum number of colors in a gd
image.
gdStyled (CONSTANT)
gdStyled _(CONSTANT)_
Used in place of a color when invoking a
line-drawing function such as gdImageLine or
gdImageRectangle. When gdStyled is used as the
@ -1729,7 +1854,7 @@ gdImageDestroy(im);
gdImageColorTransparent gdImageColorTransparent for
that mechanism.) See also gdStyledBrushed.
gdStyledBrushed (CONSTANT)
gdStyledBrushed _(CONSTANT)_
Used in place of a color when invoking a
line-drawing function such as gdImageLine or
gdImageRectangle. When gdStyledBrushed is used as
@ -1746,7 +1871,7 @@ gdImageDestroy(im);
the style are used as actual pixel colors, except
for gdTransparent.
gdDashSize (CONSTANT)
gdDashSize _(CONSTANT)_
The length of a dash in a dashed line. Defined to
be 4 for backwards compatibility with programs that
use gdImageDashedLine. New programs should use
@ -1754,7 +1879,7 @@ gdImageDestroy(im);
function with the special "color" gdStyled or
gdStyledBrushed.
gdTiled (CONSTANT)
gdTiled _(CONSTANT)_
Used in place of a normal color in
gdImageFilledRectangle, gdImageFilledPolygon,
gdImageFill, and gdImageFillToBorder. gdTiled
@ -1765,10 +1890,10 @@ gdImageDestroy(im);
gdImageFillToBorder for special restrictions
regarding those functions.
gdTransparent (CONSTANT)
gdTransparent _(CONSTANT)_
Used in place of a normal color in a style to be
set with gdImageSetStyle. gdTransparent is not the
transparent color index of the image; for that
set with gdImageSetStyle. gdTransparent is _not_
the transparent color index of the image; for that
functionality please see gdImageColorTransparent.
About the additional .gd image file format
@ -1776,12 +1901,12 @@ gdImageDestroy(im);
In addition to reading and writing the GIF format
and reading the X Bitmap format, gd has the
capability to read and write its own ".gd" format.
This format is not intended for general purpose use
and should never be used to distribute images. It
is not a compressed format. Its purpose is solely
to allow very fast loading of images your program
needs often in order to build other images for
output. If you are experiencing performance
This format is _not_ intended for general purpose
use and should never be used to distribute images.
It is not a compressed format. Its purpose is
solely to allow very fast loading of images your
program needs often in order to build other images
for output. If you are experiencing performance
problems when loading large, fixed GIF images your
program needs to produce its output images, you may
wish to examine the functions gdImageCreateFromGd
@ -1820,18 +1945,19 @@ gdImageDestroy(im);
gdImageColorTransparent | gdImageCopy |
gdImageCopyResized | gdImageCreate |
gdImageCreateFromGd | gdImageCreateFromGif |
gdImageCreateFromXbm | gdImageDashedLine |
gdImageDestroy | gdImageFill | gdImageFillToBorder
| gdImageFilledRectangle | gdImageGd |
gdImageGetInterlaced | gdImageGetPixel |
gdImageGetTransparent | gdImageGif | gdImageGreen |
gdImageInterlace | gdImageLine |
gdImageFilledPolygon | gdImagePolygon | gdImagePtr
| gdImageRectangle | gdImageRed | gdImageSetBrush |
gdImageSetPixel | gdImageSetStyle | gdImageSetTile
| gdImageString | gdImageString16 | gdImageStringUp
| gdImageStringUp16 | gdMaxColors | gdPoint |
gdImageCreateFromGifSource | gdImageCreateFromXbm |
gdImageDashedLine | gdImageDestroy | gdImageFill |
gdImageFillToBorder | gdImageFilledRectangle |
gdImageGd | gdImageGetInterlaced | gdImageGetPixel
| gdImageGetTransparent | gdImageGif |
gdImageGifToSink | gdImageGreen | gdImageInterlace
| gdImageLine | gdImageFilledPolygon |
gdImagePolygon | gdImagePtr | gdImageRectangle |
gdImageRed | gdImageSetBrush | gdImageSetPixel |
gdImageSetStyle | gdImageSetTile | gdImageString |
gdImageString16 | gdImageStringUp |
gdImageStringUp16 | gdMaxColors | gdPoint |
gdStyled | gdStyledBrushed | gdTiled |
gdTransparent
Boutell.Com, Inc.
_Boutell.Com, Inc._