Chimera Commands Index
Usage:
background solid
( color_name | current | none )
Usage:
background gradient
( color1,color2,... | palette_name | current | none )
[ discrete | RGB | HLS ]
[ opacity alpha ]
Usage:
background image
( image_file | current | none )
[ zoomed | stretched | centered | tiled ]
[ scale factor ]
[ opacity alpha ]
The background command sets the
graphics window
background to a single solid color,
a gradient of multiple colors,
or an image from a file.
These settings can also be adjusted (and saved for later uses of Chimera) with
the Background preferences.
Background transparency in Chimera-rendered PNG or TIFF images
can be specified in the Save Image dialog
or at startup with the --bgopacity
option (e.g., if images will be saved with the
copy command instead of the dialog).
For background transparency in raytraced
images, see the POV-Ray
Options preferences.
See also:
color,
colordef,
set,
Effects,
the Color Editor,
the Palette Editor,
coloring,
movie-related commands
Except for the words current and none, the
keywords can be truncated and their case does not matter.
Optional keywords can be given in any order. Examples:
background solid light blue
back grad coral,deep sky blue,navy blue rgb
back image ~/Desktop/scenery.png sc 0.5 center
back im current op 0.25
The command background solid
is equivalent to set bgColor and
sets the background to a single solid color.
The color can be specified as:
- color_name - any color name
that specifies a single color. Any transparency in the color will be ignored.
- current - the current solid color
- none (default background)
- no color, in this case equivalent to black
By default, the color used for depth cueing
will match the solid background color, but it can be changed independently
(for example, with the command
set dcColor).
Background gradient sets the background to a vertical gradient
of multiple colors, given as one of the following:
- a comma-separated list of at least two color names in bottom-to-top order.
Each can be any color name
that specifies a single color, except that R,G,B[,A] tuples cannot be used.
- palette_name - the name of a
palette, as defined and listed in the
Palette Editor
- current - the current gradient color series and
interpolation method.
The default gradient is white at the bottom, blue at the top, HLS-interpolated.
- none - no gradient;
set the background to the current solid color
The gradient colors can be shown as discrete bands
or interpolated in the RGB (red-green-blue) or
HLS (hue-lightness-saturation) color space,
where the latter is the default.
If an interpolation method is specified along with a palette name,
the specification will override the method included in the
palette.
The alpha value can range from 0.0, meaning complete transparency,
to 1.0, meaning complete opacity (default). If the gradient is transparent,
the current solid color will show through.
If a transparent gradient is used together with a
transparent background, the background of
an image saved from Chimera as PNG or TIFF will not only show the blending
of the gradient over the solid color, but also have the same overall
opacity as was specified for the gradient.
Background image specifies using an image from a file.
Accepted formats include PNG, TIFF, and JPEG.
The word current can be used to indicate a previously specified image.
The word none indicates resetting the current image to nothing
and changing the background to the current solid color.
If image is the last word of the command
(in this case, it can be placed after the options), a
dialog for browsing the filesystem will appear.
The image is fit into the graphics window according to one of the following
modes:
- zoomed (default)
- automatically scale the image to fill the window, cropping the top/bottom
or sides of the image as needed (no image distortion)
- stretched
- automatically scale the image to fill the window,
stretching or squashing the image as needed
- centered - center the image;
any surrounding border will be shown in the current
solid color
- tiled - tile the image
The scale is expressed as a factor relative to the actual
image size and only affects the centered and tiled modes.
The opacity value alpha can range from 0.0,
meaning complete transparency, to 1.0, meaning complete opacity (default).
If the image is transparent,
the current solid color will show through.
If a transparent background image is used together with a
transparent background, the background of
an image saved from Chimera as PNG or TIFF will not only show the blending
of the background image over the solid color, but also have the same overall
opacity as was specified for the background image.