A Program to Browse Open Type Font Files

This is a morphic application for Squeak 3.7 and Squeak 3.8. It can be used to explore the contents of OpenType™ font files.

User Guide

To open the Font File Viewer, evaluate this statement:

MorphicTTFReader openAsMorph

You obtain this window:

The OpenType Font File Viewer

At the top left corner of this window, you see a button with title file:. To open a font file, you left-click this button. You obtain a menu of font file names (with extensions *.ttf and *.ttc) and select a file. (When you press that button the first time, you will be asked for the location of the fonts on your computer. The font directory is stored in class variable FontDirectory of class MorphicTTFReader. To change that setting, right-click on the file: button.)

As soon as a *.ttf file is read, a resumee of the most important font properties is displayed. Also displayed is the font name (in the drop down list on the left) and a list of selectable information items.

For a *.ttc file that contains more than one font, no font name is displayed; you have to select one.

The Font Description

Most OpenType fonts contain two different glyph mappings: One for the Apple and one for Unicode BMP. To explore a font, you have to select one glyph mapping. You do this with the drop down list on the right.

As soon as you have choosen a glyph mapping, additional information items become selectable.

An Encoding is now selected

You may wish to see a summary of the tables in the font file. The summary gives the table names, the table sizes and a short explanation.

The Table Overview

When you explore a font, you want to see its glyphs. The explore the glyphs, you select

When you select one of these options, the glyph selection morph is displayed. It contains one line of 16 selectable boxes and two grid boxes with 256 small boxes each. The line is used to select the Unicode plane (most fonts support only plane 0, the BMP). The upper box is used to the select the heigh-value byte of an Unicode codepoint and the lower box is used to select the low-value byte of an codepoint. With three selections, you can select every single codepoint. Note that grayed boxes are not selectable.

The Glyph Selection Morph

When it is selected, the glyph table displays one page of glyphs as soon as you have selected a plane and a page. Glyph that are displayed in blue have serveral display forms.

When you select a low-value byte, the selected glyph is shown with red box. On the following image, the codepoint x76F4 is selected. It contains a CJK ideograph for which the font Arial Unicode MS provides serveral display forms.

A Table of Glyphs

To see the display forms, you switch to the glyph view. It shows one enlarged glyph in its center and a list of selectable variants on the right. The selected variant is drawn with a red border. On the following image, the default form of the glyph is selected, for Arial Unicode MS this is the japanese variant. The other variants are for Korean and for traditional Chinese.

A Glyph with two Variants

Arial Unicode MS is a hinted font. You can press the hint button to see the hints. Hints are instructions for a virtual machine, the font renderer.

The Hints

Useful Links: