SB021 - Symbol Font Utility Program

The program is used to maintain symbol fonts and performs the following tasks:

• Viewing and updating of font header characteristics.

• Creation of new symbol fonts.

• Copying of symbol fonts.

• Deletion of symbol fonts.

The program interacts with the user via the Main Activity form and a number of sub forms which are the:

• Font Head Viewer form.

• Font Copy Utility form.

• Font Delete Utility form.

Individual symbols within a symbol font are maintained by the Marine Drafting System.

Font Identification and Residence

A symbol font is identified by a number between 1 and 999.The corresponding font file is named d012sy<xxx>.port where xxx stands for the identification, left padded with zeros. The directory where the font files reside is initially project dependant (SBB_SYMBDIR) but can be changed to whatever desired inside the program.

The Main Activity Form

When starting up the program this form is entered. From here the following sub tasks can be selected:

• View

• Copy

• Delete

The tasks are handled by suitable sub forms, each one described in separate sections below. You will always return to this form when selecting Cancel from any of the sub-forms. To quit the session, select Quit.

The Font Head Viewer Form

This form is used to view, update or create symbol fonts. The source symbol font is specified in the Directory and Identification fields respectively. The font header characteristics are shown in the section labelled Characteristics and contains the following:

1. The total number of slots

2. The size of a slot, in words

3. The symbol origin (reference point)

4. The text code (not in use at present)

5. The highest slot number in use

6. The used slot size, in words

7. The revision number of the font Characteristics here while (5) to (7) are for viewing purposes only. Each slot corresponds to a symbol, identified by the slot number.

Viewing Fonts

To View the characteristics of a font, select Read. The font header characteristics will be shown.

Updating Fonts

To Update the characteristics of a font, select Update. The font header characteristics (1) to (4) will be updated according to the current values in the form. For example, the total size of a symbol font depends on (1) and (2) and can be optimized for performance reasons.

Note: The contents of the symbol font will not be changed.

Creating Fonts

To Create a new symbol font, select Create. A new (empty) font with the header characteristics (1) to (4) given in the form will be created. Individual symbols can now be defined within the Marine Drafting System.

Default Characteristics

The current font header characteristics (1) to (4), used when creating or updating a font, can be set to default values by selecting Default.

The Font Copy Utility Form

This form is used to copy a symbol font. The source and target fonts are specified in the Directory and Identification fields respectively. The source font must of course exist while the target font must not. To overwrite an existing font you first have to delete this font explicitly.

The Font Delete Utility Form

This form handles the deletion of symbol fonts and should be used with extreme care because the fonts are deleted WITHOUT ANY CONFIRMATION. The source font is specified in the Directory and Identification fields respectively.

Note: Normally, symbols are drawn with solid lines only.

The environment variable TB_SHOW_SYMBOL_WITH_FULL_LINETYPE controls the display of a symbol in the drawing:

• If set to YES, the actual line type will be used

• Otherwise, the symbol will be displayed as solid with same thickness as the actual line type