Font String Forms

FontManager

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» String Forms

Starting with FontManager 3.41, Font_Paint and Font_ScanString now accept strings in 8, 16 or 32-bit forms. This is invoked by bits 12 & 13 in the flags in R2.

All other Font SWIs only accept 8-bit strings.

A 16-bit string must be half-word aligned, and consists of a number of 16-bit halfwords. A 32-bit string must be word aligned, and consists of a number of 32-bit words.

Below is how the string “Hello” is represented in 8, 16 and 32-bit string form.

This allows access to characters outside the first 256. Control codes work as before, but have to be introduced by a character of the appropriate width.

The parameters of control sequences are handled differently in 16 and 32-bit modes. More information is available on font’s encoding.

Regardless of the setting of the 16/32-bit bits, string lengths continue to be in bytes (such as R7 on entry to Font_Paint).

See also

• Font_Paint

• Control Characters
• Font_Paint Block
• Font_Paint Flags
• Font_Paint Special Characters Parameters
• Font Background Blending
• Font Encoding Identifier
• Font Transformation Matrix