gd_gd2.c

Summary
gd_gd2.c
Functions
gdImageCreateFromGd2gdImageCreateFromGd2 is called to load images from gd2 format files.
gdImageCreateFromGd2Ptr
gdImageCreateFromGd2CtxReads in a GD2 image via a gdIOCtx struct.
gdImageCreateFromGd2PartgdImageCreateFromGd2Part is called to load parts of images from gd2 format files.
gdImageCreateFromGd2PartPtr
gdImageCreateFromGd2PartCtx

Functions

gdImageCreateFromGd2

gdImagePtr gdImageCreateFromGd2 (FILE *inFile)

gdImageCreateFromGd2 is called to load images from gd2 format files.  Invoke gdImageCreateFromGd2 with an already opened pointer to a file containing the desired image in the gd2 file format, which is specific to gd2 and intended for fast loading of parts of large images.  (It is a compressed format, but generally not as good as maximum compression of the entire image would be.)

gdImageCreateFromGd2 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).  gdImageCreateFromGd2 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.

Variants

gdImageCreateFromGd2Ptr creates an image from GD data (i.e. the contents of a GD2 file) already in memory.

gdImageCreateFromGd2Ctx reads in an image using the functions in a gdIOCtx struct.

Parameters

infileThe input FILE pointer

Returns

A pointer to the new image or NULL if an error occurred.

Example

gdImagePtr im;
FILE *in;
in = fopen("mygd.gd2", "rb");
im = gdImageCreateFromGd2(in);
fclose(in);
// ... Use the image ...
gdImageDestroy(im);

gdImageCreateFromGd2Ptr

gdImagePtr gdImageCreateFromGd2Ptr (int size,
void *data)

Parameters

sizesize of GD2 data in bytes.
dataGD2 data (i.e. contents of a GIF file).

See gdImageCreateFromGd2.

gdImageCreateFromGd2Ctx

gdImagePtr gdImageCreateFromGd2Ctx (gdIOCtxPtr in)

Reads in a GD2 image via a gdIOCtx struct.  See gdImageCreateFromGd2.

gdImageCreateFromGd2Part

gdImagePtr gdImageCreateFromGd2Part (FILE *inFile,
int srcx,
int srcy,
int w,
int h)

gdImageCreateFromGd2Part is called to load parts of images from gd2 format files.  Invoked in the same way as gdImageCreateFromGd2, but with extra parameters indicating the source (x, y) and width/height of the desired image.  gdImageCreateFromGd2Part returns a gdImagePtr to the new image, or NULL if unable to load the image.  The image must eventually be destroyed using gdImageDestroy.

Variants

gdImageCreateFromGd2PartPtr creates an image from GD2 data (i.e. the contents of a GD2 file) already in memory.

gdImageCreateFromGd2Ctx reads in an image using the functions in a gdIOCtx struct.

Parameters

infileThe input FILE pointer
srcx, srcyThe source X and Y coordinates
w, hThe resulting image’s width and height

Returns

A pointer to the new image or NULL if an error occurred.

gdImageCreateFromGd2PartPtr

gdImagePtr gdImageCreateFromGd2PartPtr (int size,
void *data,
int srcx,
int srcy,
int w,
int h)

Parameters

sizesize of GD data in bytes.
dataGD data (i.e. contents of a GIF file).
srcx, srcyThe source X and Y coordinates
w, hThe resulting image’s width and height

Reads in part of a GD2 image file stored from memory.  See gdImageCreateFromGd2Part.

gdImageCreateFromGd2PartCtx

gdImagePtr gdImageCreateFromGd2PartCtx (gdIOCtx *in,
int srcx,
int srcy,
int w,
int h)

Parameters

inThe data source.
srcx, srcyThe source X and Y coordinates
w, hThe resulting image’s width and height

Reads in part of a GD2 data image file via a gdIOCtx struct.  See gdImageCreateFromGd2Part.

gdImagePtr gdImageCreateFromGd2 (FILE *inFile)
gdImageCreateFromGd2 is called to load images from gd2 format files.
gdImagePtr gdImageCreateFromGd2Ptr (int size,
void *data)
gdImagePtr gdImageCreateFromGd2Ctx (gdIOCtxPtr in)
Reads in a GD2 image via a gdIOCtx struct.
gdIOCtx structures hold function pointers for doing image IO.
gdImagePtr gdImageCreateFromGd2Part (FILE *inFile,
int srcx,
int srcy,
int w,
int h)
gdImageCreateFromGd2Part is called to load parts of images from gd2 format files.
gdImagePtr gdImageCreateFromGd2PartPtr (int size,
void *data,
int srcx,
int srcy,
int w,
int h)
gdImagePtr gdImageCreateFromGd2PartCtx (gdIOCtx *in,
int srcx,
int srcy,
int w,
int h)
The data structure in which gd stores images.
void gdImageDestroy (gdImagePtr im)
gdImageDestroy is used to free the memory associated with an image.
Close