dstyle - format of .dstyle files (display styles)
Display styles indicate how to render information on a screen.
Each style describes one way of rendering information, for example as a
solid area in red or as a dotted outline in purple. Different styles
correspond to mask layers, highlights, labels, menus, window borders, and so
on. See ``Magic Maintainer's Manual #3: Display Styles, Color Maps, and
Glyphs'' for more information on how the styles are used.
Dstyle files usually have names of the form
x.y.dstylen, where x is a class of
technologies, y is a class of displays, and n is a version
number (currently 5). The version number may increase in the future
if the format of dstyle files changes. For example, the display style file
mos.7bit.dstyle5 provides all the rendering information for our nMOS
and CMOS technologies for color displays with at least 7 bits of color.
Dstyle files are stored in ASCII as a series of lines. Lines
beginning with ``#'' are considered to be comments and are ignored. The rest
of the lines of the file are divided up into two sections separated by blank
lines. There should not be any blank lines within a section.
The first section begins with a line display_styles
planes where planes is the number of bits of color information
per pixel on the screen (between 1 and 8). Each line after that describes
one display style and contains eight fields separated by white space:
style writeMask color outline fill stipple shortName longName The
meanings of the fields are:
- style
- The number of this style, in decimal. Styles 1 through 64 are used to
display mask layers in the edit cell. The style number(s) to use for each
mask layer is (are) specified in the technology file. Styles 65-128 are
used for displaying mask layers in non-edit cells. If style x is
used for a mask layer in the edit cell, style x+64 is used for the
same mask layer in non-edit cells. Styles above 128 are used by the Magic
code for various things like menus and highlights. See the file
styles.h in Magic for how styles above 128 are used. When
redisplaying, the styles are drawn in order starting at 1, so the order of
styles may affect what appears on the screen.
- writeMask
- This is an octal number specifying which bit-planes are to be modified
when this style is rendered. For example, 1 means only information in
bit-plane 0 will be affected, and 377 means all eight bit-planes are
affected.
- color
- An octal number specifying the new values to be written into the
bit-planes that are modified. This is used along with writeMask to
determine the new value of each pixel that's being modified: newPixel =
(oldPixel & ∼writeMask) | (color & writeMask) The red,
green, and blue intensities displayed for each pixel are not deterimined
directly by the value of the pixel; they come from a color map that maps
the eight-bit pixel values into red, green, and blue intensities. Color
maps are stored in separate files.
- outline
- If this field is zero, then no outline is drawn. If the field is non-zero,
it specifies that outlines are to be drawn around the rectangular areas
rendered in this style, and the octal value gives an eight-bit pattern
telling how to draw the outline. For example, 377 means to draw a solid
line, 252 means to draw a dotted line, 360 specifies long dashes, etc.
This field only indicates which pixels will be modified: the
writeMask and color fields indicate how the pixels are
modified.
- fill
- This is a text string specifying how the areas drawn in this style should
be filled. It must have one of the values solid, stipple,
cross, outline, grid. Solid means that every
pixel in the area is to modified according to writeMask and
color. Stipple means that the area should be stippled: the
stipple pattern given by stipple is used to determine which pixels
in the area are to be modified. Cross means that an X is drawn in a
solid line between the diagonally-opposite corners of the area being
rendered. Outline means that the area should not be filled at all;
only an outline is drawn (if specified by outline). Grid is
a special style used to draw a grid in the line style given by
outline. The styles cross and stipple may be
supplemented with an outline by giving a non-zero outline field.
The outline and grid styles don't make sense without an an
outline, and solid doesn't make sense with an outline (since all
the pixels are modified anyway).
- stipple
- Used when fill is stipple to specify (in decimal) the
stipple number to use.
- shortName
- This is a one-character name for this style. These names are used in the
specification of glyphs and also in a few places in the Magic source code.
Most styles have no short name; use a ``-'' in this field for them.
- longName
- A more human-readable name for the style. It's not used at all by
Magic.
The second section of a dstyle file is separated from the first by
a blank line. The first line of the second section must be stipples
and each additional line specifies one stipple pattern with the syntax
number pattern name Number is a decimal number used to name
the stipple in the stipple fields of style lines. Number must
be no less than 1 and must be no greater than a device-dependent upper
limit. Most devices support at least 15 stipple patterns. Pattern
consists of eight octal numbers, each from 0-377 and separated by white
space. The numbers form an 8-by-8 array of bits indicating which pixels are
to be modified when the stipple is used. The name field is just a
human-readable description of the stipple; it isn't used by Magic.
∼cad/lib/magic/sys/mos.7bit.dstyle5