NAME¶
XmGetPixmapByDepth — A pixmap caching function that generates a
pixmap, stores it in a pixmap cache, and returns the pixmap
"XmGetPixmapByDepth" "pixmaps"
SYNOPSIS¶
#include <Xm/Xm.h>
Pixmap XmGetPixmapByDepth(
Screen *screen,
char *image_name,
Pixel foreground,
Pixel background,
int depth);
DESCRIPTION¶
XmGetPixmapByDepth uses the parameter data to perform a lookup in the
pixmap cache to see if a pixmap has already been generated that matches the
data. If one is found, a reference count is incremented and the pixmap is
returned. Applications should use
XmDestroyPixmap when the pixmap is no
longer needed.
- screen
- Specifies the display screen on which the pixmap is to be drawn
- image_name
- Specifies the name of the image to be used to generate the pixmap
- foreground
- Combines the image with the foreground color to create the pixmap
if the image referenced is a bit-per-pixel image
- background
- Combines the image with the background color to create the pixmap
if the image referenced is a bit-per-pixel image
- depth
- Specifies the depth of the pixmap
If a matching pixmap is not found,
image_name is used to perform a lookup
in the image cache. If an image is found, it is used to generate the pixmap,
which is then cached and returned.
If an image is not found,
image_name is used as a filename, and a search
is made for an
X10 or
X11 bitmap file. If it is found, the file
is read, converted into an image, and cached in the image cache. The image is
then used to generate a pixmap, which is cached and returned.
If
image_name has a leading / (slash), it specifies a full pathname, and
XmGetPixmapByDepth opens the file as specified. Otherwise,
image_name specifies a filename. In this case,
XmGetPixmapByDepth looks for the file along a search path specified by
the
XBMLANGPATH environment variable or by a default search path, which
varies depending on whether or not the
XAPPLRESDIR environment variable
is set. The default search path contains a lot of directories. Therefore,
XmGetPixmapByDepth will need a relatively long time to search through
all these directories for pixmaps and bitmaps. Applications that use a lot of
pixmaps and bitmaps will probably run more quickly if
XBMLANGPATH is
set to a short list of directories. In addition to X bitmap files (XBM), Motif
also supports XPM (X Pixmap) file formats, and, from version 2.3, JPEG and PNG
image formats. (Note that support of JPEG and PNG image format is an optional
feature of Motif, in order to check if current version supports PNG and JPEG
image formats the PNG_SUPPORT and JPEG_SUPPORT macros should be checked
correspondingly.) The
XBMLANGPATH specifies the path for both XBM, XPM,
PNG and JPEG files. XPM files are described in more detail later in this
reference page.
The
XBMLANGPATH environment variable specifies a search path for X bitmap
files. It can contain the substitution field
%B, where the
image_name argument to
XmGetPixmapByDepth is substituted for
%B. It can also contain the substitution fields accepted by
XtResolvePathname. The substitution field
%T is always mapped to
bitmaps, and
%S is always mapped to NULL.
If
XBMLANGPATH is not set, but the environment variable
XAPPLRESDIR is set, the following pathnames are searched:
- •
- %B
- •
- $XAPPLRESDIR/%L/bitmaps/%N/%B
- •
- $XAPPLRESDIR/%l_%t/bitmaps/%N/%B
- •
- $XAPPLRESDIR/%l/bitmaps/%N/%B
- •
- $XAPPLRESDIR/bitmaps/%N/%B
- •
- $XAPPLRESDIR/%L/bitmaps/%B
- •
- $XAPPLRESDIR/%l_%t/bitmaps/%B
- •
- $XAPPLRESDIR/%l/bitmaps/%B
- •
- $XAPPLRESDIR/bitmaps/%B
- •
- $HOME/bitmaps/%B
- •
- $HOME/%B
- •
- /usr/lib/X11/%L/bitmaps/%N/%B
- •
- /usr/lib/X11/%l_%t/bitmaps/%N/%B
- •
- /usr/lib/X11/%l/bitmaps/%N/%B
- •
- /usr/lib/X11/bitmaps/%N/%B
- •
- /usr/lib/X11/%L/bitmaps/%B
- •
- /usr/lib/X11/%l_%t/bitmaps/%B
- •
- /usr/lib/X11/%l/bitmaps/%B
- •
- /usr/lib/X11/bitmaps/%B
- •
- /usr/include/X11/bitmaps/%B
If neither
XBMLANGPATH nor
XAPPLRESDIR is set, the following
pathnames are searched:
- •
- %B
- •
- $HOME/%L/bitmaps/%N/%B
- •
- $HOME/%l_%t/bitmaps/%N/%B
- •
- $HOME/%l/bitmaps/%N/%B
- •
- $HOME/bitmaps/%N/%B
- •
- $HOME/%L/bitmaps/%B
- •
- $HOME/%l_%t/bitmaps/%B
- •
- $HOME/%l/bitmaps/%B
- •
- $HOME/bitmaps/%B
- •
- $HOME/%B
- •
- /usr/lib/X11/%L/bitmaps/%N/%B
- •
- /usr/lib/X11/%l_%t/bitmaps/%N/%B
- •
- /usr/lib/X11/%l/bitmaps/%N/%B
- •
- /usr/lib/X11/bitmaps/%N/%B
- •
- /usr/lib/X11/%L/bitmaps/%B
- •
- /usr/lib/X11/%l_%t/bitmaps/%B
- •
- /usr/lib/X11/%l/bitmaps/%B
- •
- /usr/lib/X11/bitmaps/%B
- •
- /usr/include/X11/bitmaps/%B
These paths are defaults that vendors may change. For example, a vendor may use
different directories for
/usr/lib/X11 and
/usr/include/X11.
The following substitutions are used in these paths:
- %B
- The image name, from the image_name argument
- %N
- The class name of the application
- %L
- The display's language string. This string is influenced by
XtSetLanguageProc. The default string is determined by calling
setlocale( LC_ALL, NULL).
- %l_%t
- The language and territory component of the display's language string
- %l
- The language component of the display's language string
The contents of the file must conform to the rules for X11 bitmap files. In
other words, Motif can read any X11 conformant bitmap file.
The XPM file format is used for storing or getting back colored X pixmaps from
files. The XPM library is provided as unsupported with Motif. To build
applications without XPM, use the
NO_XPM macro. The following shows
both XBM and XPM files, respectively, for a plaid pattern.
/* XBM file */
#define plaid_width 22
#define plaid_height 22
#define plaid_x_hot -1
#define plaid_y_hot -1
static char plaid_bits[] = {
0x75, 0xfd, 0x3f, 0xaa, 0xfa, 0x3e, 0x75, 0xfd, 0x3f, 0xaa, 0xfa, 0x3e,
0x75, 0xfd, 0x3f, 0xff, 0x57, 0x15, 0x75, 0xfd, 0x3f, 0xaa, 0xfa, 0x3e,
0x75, 0xfd, 0x3f, 0xaa, 0xfa, 0x3e, 0x75, 0xfd, 0x3f, 0x20, 0xa8, 0x2b,
0x20, 0x50, 0x15, 0x20, 0xa8, 0x2b, 0x20, 0x50, 0x15, 0x20, 0xa8, 0x2b,
0xff, 0xff, 0x3f, 0x20, 0xa8, 0x2b, 0x20, 0x50, 0x15, 0x20, 0xa8, 0x2b,
0x20, 0x50, 0x15, 0x20, 0xa8, 0x2b};
/* XPM file */
static char * plaid[] = {
/* plaid pixmap
* width height ncolors chars_per_pixel */
"22 22 4 2 ",
/* colors */
" c red m white s light_color ",
"Y c green m black s lines_in_mix ",
"+ c yellow m white s lines_in_dark ",
"x m black s dark_color ",
/* pixels */
"x x x x x x x x x x x x + x x x x x ",
" x x x x x x x x x x x x x x x x ",
"x x x x x x x x x x x x + x x x x x ",
" x x x x x x x x x x x x x x x x ",
"x x x x x x x x x x x x + x x x x x ",
"Y Y Y Y Y x Y Y Y Y Y + x + x + x + x + x + ",
"x x x x x x x x x x x x + x x x x x ",
" x x x x x x x x x x x x x x x x ",
"x x x x x x x x x x x x + x x x x x ",
" x x x x x x x x x x x x x x x x ",
"x x x x x x x x x x x x + x x x x x ",
" x x x x Y x x x ",
" x x x Y x x ",
" x x x x Y x x x ",
"x x x x x x x x x x x x x x x x x x x x x x ",
" x x x x Y x x x ",
" x x x Y x x ",
" x x x x Y x x x ",
" x x x Y x x ",
" x x x x Y x x x "
};
RETURN¶
Returns a pixmap when successful; returns
XmUNSPECIFIED_PIXMAP if the
image corresponding to
image_name cannot be found.
XmDestroyPixmap(3),
XmInstallImage(3), and
XmUninstallImage(3).