NAME
XcmsQueryColor, XcmsQueryColors, XcmsLookupColor - obtain color values
SYNTAX
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);
ARGUMENTS
- 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 string.
- 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.
DESCRIPTION
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.
DIAGNOSTICS
- 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.
SEE ALSO
XcmsAllocColor(3), XcmsStoreColor(3), XQueryColor(3)
Xlib - C Language X Interface