Table of Contents
XcmsQueryColor, XcmsQueryColors,
XcmsLookupColor - obtain color values
- Status XcmsQueryColor(Display
*display, Colormap colormap,
- XcmsColor *color_in_out, XcmsColorFormat result_format);
- Status XcmsQueryColors(Display *display, Colormap
- colormap, XcmsColor
colors_in_out[], unsigned int ncolors, XcmsColorFormat result_format);
- Status XcmsLookupColor(Display *display, Colormap
- colormap, char *color_string,
XcmsColor *color_exact_return, XcmsColor *color_screen_return, XcmsColorFormat
result_format);
- display
- Specifies the connection to the X server.
- colormap
- Specifies the colormap.
- color_exact_return
- Returns the color specification
parsed from the color string or parsed from the corresponding string found
in a color-name database.
- color_in_out
- Specifies the pixel member that indicates
the color cell to query. The color specification stored for the color cell
is returned in this XcmsColor structure.
- color_screen_return
- Returns the
color that can be reproduced on the screen.
- color_string
- Specifies the color
stringSt.
- result_format
- Specifies the color format for the returned color
specifications (color_screen_return and color_exact_return arguments). If
the format is XcmsUndefinedFormat and the color string contains a numerical
color specification, the specification is returned in the format used in
that numerical color specification. If the format is XcmsUndefinedFormat
and the color string contains a color name, the specification is returned
in the format used to store the color in the database.
- ncolors
- Specifies
the number of XcmsColor structures in the color-specification array.
The
XcmsQueryColor function obtains the RGB value for the pixel value in
the pixel member of the specified XcmsColor structure and then converts
the value to the target format as specified by the result_format argument.
If the pixel is not a valid index in the specified colormap, a BadValue
error results. The XcmsQueryColors function obtains the RGB values for
pixel values in the pixel members of XcmsColor structures and then converts
the values to the target format as specified by the result_format argument.
If a pixel is not a valid index into the specified colormap, a BadValue
error results. If more than one pixel is in error, the one that gets reported
is arbitrary.
XcmsQueryColor and XcmsQueryColors can generate BadColor
and BadValue errors.
The XcmsLookupColor function looks up the string
name of a color with respect to the screen associated with the specified
colormap. It returns both the exact color values and the closest values
provided by the screen with respect to the visual type of the specified
colormap. The values are returned in the format specified by result_format.
If the color name is not in the Host Portable Character Encoding, the
result is implementation-dependent. Use of uppercase or lowercase does not
matter. XcmsLookupColor returns XcmsSuccess or XcmsSuccessWithCompression
if the name is resolved; otherwise, it returns XcmsFailure. If XcmsSuccessWithCompression
is returned, the color specification returned in color_screen_return
is the result of gamut compression.
- BadColor
- A value for a
Colormap argument does not name a defined Colormap.
- BadValue
- Some numeric
value falls outside the range of values accepted by the request. Unless
a specific range is specified for an argument, the full range defined by
the argument's type is accepted. Any argument defined as a set of alternatives
can generate this error.
XcmsAllocColor(3X11)
, XcmsStoreColor(3X11)
,
XQueryColor(3X11)
Xlib - C Language X Interface
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