aiSee User Manual: Icons and Fonts

Icons

In addition to text labels, aiSee also offers the option of displaying icon files in nodes. The icon files have to be in PNG, PBM, PGM, or PPM (raw) format. They can be attached to summary nodes or ordinary nodes by using the iconfile attribute in subgraph or node specifications.

In order to prevent the title text from being drawn over the icon displayed, the label attribute of the node or summary node can be set to the empty string, i.e. label: "".

The search path for the icon files can be specified by the environment variable AISEEICONS. The default search path is .:/usr/local/share/aiSee/icons. It can be changed as follows:

Shell	Command
`tcsh`	`% setenv AISEEICONS /path/to/my/icons`
`bash`	`> export AISEEICONS=/path/to/my/icons`

The following additional GDL top-level graph attributes influence the drawing of icons:

`icons: yes` or `no` default is `yes`	`no` disables displaying of icons in nodes. Displaying of icons can be enabled again interactively from the View dialog box.
`fast_icons: yes` or `no` default is `no`	`yes` causes icon file loading to be faster, which may negatively impact the quality of the drawing if not all the icon colors are present.
`iconcolors: Int` default is `32`	Specifies the size of the color map used for drawing icons. The maximum value is `256`.

Example graphs:

Additional bitmap fonts

Apart from the default vector font, aiSee offers the bitmap fonts listed in the table below. These pixel fonts are compatible with Adobe PostScript and SVG fonts. When exporting graphs to PostScript, the original PostScript fonts can be used (providing your PostScript printer is equipped with these fonts).

The additional bitmap fonts can be specified by the fontname attribute for summary nodes, ordinary nodes and edge labels. The string value of this attribute is the font file name of the font to be used. It is composed of the font name base and size:

fontname: "BaseSize"

For example, a size 12 Helvetica Bold font is specified via fontname: "helvB12". Available font sizes are: 08, 10, 12, 14, 18 and 24 points. See the table below for the available font name bases.

`Base`	Corresponding PostScript font	`Base`	Corr. PostScript font
`helvB`	Helvetica Bold	`courB`	Courier Bold
`helvBO`	Helvetica Bold Oblique	`courBO`	Courier Bold Oblique
`helvO`	Helvetica Oblique	`courO`	Courier Oblique
`helvR`	Helvetica	`courR`	Courier
`ncenB`	New Century Schoolbook Bold	`timB`	Times Bold
`ncenBI`	New Century Schoolbook Bold Italic	`timBI`	Times Bold Italic
`ncenI`	New Century Schoolbook Italic	`timI`	Times Italic
`ncenR`	New Century Schoolbook	`timR`	Times Roman
		`symb`	Symbol

Troubleshooting

If aiSee cannot find the bitmap font files for some reason, the standard vector font is used instead. The default search path for the font files is .:/usr/local/share/aiSee/fonts. It can be changed by setting the environment variable AISEEFONTS accordingly.

Alternatively, the complete path to the font file can be specified in the GDL source itself, for example:

node.fontname: "/home/joe/aisee_fonts/helvB10.vcf"

If aiSee is running on a Web server, please double-check that the font file directory is specified correctly — especially if the server is a virtual one. (For Apache, check out the value of the environment variable “DOCUMENT_ROOT”.)

Compatibility with SVG

We highly recommend using the bitmap fonts when exporting graphs to SVG format. The standard vector font is translated into <line> elements, whereas the bitmap fonts are translated into <text>. SVG treats <text> as text rather than outlines, enabling the user to search SVG images for node/edge/subgraph labels by using the Find dialog in the SVG viewer. Also, because each <text> element usually replaces dozens of <line> elements, the SVG file is much smaller and loads faster.

An iconfile specification is translated into an <image> element. The <image> element indicates to the SVG viewer used that the contents of the icon file specified are to be rendered into a given rectangle within the current user coordinate system. SVG viewers usually support at least PNG, JPEG and SVG format icon files.

From version 2.2.04 on, aiSee also offers the option of embedding the icons in the output SVG file rather that just referencing them by their paths (see example).

Example graphs:

2003 NFL postseason / Super Bowl XXXVIII

The tables below show how the various bitmap fonts are translated into SVG.

GDL font `base`	SVG `font-family`
`helvR`	`"Helvetica"`
`helvB`	`"Helvetica-Bold"`
`helvO`	`"Helvetica-Oblique"`
`helvBO`	`"Helvetica-BoldOblique"`
`courR`	`"Courier New"`
`courB`	`"Courier New-Bold"`
`courO`	`"Courier New-Oblique"`
`courBO`	`"Courier New-BoldOblique"`
`ncenR`	`"NewCenturySchlbk"`
`ncenB`	`"NewCenturySchlbk-Bold"`
`ncenI`	`"NewCenturySchlbk-Italic"`
`ncenBI`	`"NewCenturySchlbk-BoldItalic"`
`timR`	`"Times"`
`timB`	`"Times-Bold"`
`timI`	`"Times-Italic"`
`timBI`	`"Times-BoldItalic"`
`symb`	`"Symbol"`

From release 2.1.60 on, the GDL font size specified is automatically increased by 2pt (for export to SVG only).

GDL font `size`	SVG `font-size`
`08`	`"10"`
`10`	`"12"`
`12`	`"14"`
`14`	`"16"`
`18`	`"20"`
`24`	`"26"`

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