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Font_ReadFontMetrics
Programmer's Reference Manuals
» Part 8 - Non-kernel input/output
» The Font Manager
» SWI Calls
» Font_ReadFontMetrics
Font_ReadFontMetrics
(SWI &4009F)
| Entry | |
|---|---|
| R0 | Font handle |
| R1 | Pointer to buffer for bounding box array, 0 to read size |
| R2 | Pointer to buffer for X width data, 0 to read size |
| R3 | Pointer to buffer for Y width data, 0 to read size |
| R4 | Pointer to buffer for miscellaneous data, 0 to read size |
| R5 | Pointer to buffer for kerning data, 0 to read size |
| R6 | Pointer to buffer for new style kerning data, 0 to read size1 |
| R7 | 0 |
1 Available from version 3.41 onwards.
| Exit | |
|---|---|
| R0 | File flags |
| R1 | Size of bounding box data |
| R2 | Size of X width data |
| R3 | Size of Y width data |
| R4 | Size of miscellaneous data |
| R5 | Size of kerning data |
| R6 | Size of new style kerning data |
| R7 | Corrupted (maybe) |
Use
This purpose of this call is to read information in the font’s IntMetrics file.
Notes
Currently it is not permitted on fonts which have a transformation matrix applied. All values are signed millipoints, unless specifically stated.
Width data is an array of 256 words, bounding box data an array of 256 x4 words (x0, y0, x1, y1). This data is only returned for the first 256 characters of the font.
This call is of doubtful use for fonts with up to 2 billion characters, so should use Font_CharBBox or Font_ScanString instead of using R1 to R3 in this call.
The output values of R1 to R6 will be zero if no information is present in the file be examined.