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Font String Forms

FontManager
» Technical Details
» 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.

String form Data
8-bit 48 65 6C 6C 6F 00
16-bit 0048 0065 006C 006C 006F 0000
32-bit 00000048 00000065 0000006C 0000006C 0000006F 00000000

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
Revised on September 26, 2017 13:40:47 by Jeffrey Lee (213) (62.252.28.250)
Edit | Back in time (5 revisions) | See changes | History | Views: Print | Source | Linked from: Font Background Blending, Font_Paint Special Characters, Font_Paint Flags, Font_ScanString Flags, Font_Paint Special Characters Parameters, FontManager Technical Details

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