| Summary: |
Font option CAIRO_HINT_METRICS_OFF unhonoured on win32 (and a fix) |
| Product: |
cairo
|
Reporter: |
Richard Procter <richard.n.procter> |
| Component: |
win32 backend | Assignee: |
cairo-bugs mailing list <cairo-bugs> |
| Status: |
RESOLVED
FIXED
|
QA Contact: |
cairo-bugs mailing list <cairo-bugs> |
| Severity: |
normal
|
|
|
| Priority: |
medium
|
CC: |
freedesktop
|
| Version: |
1.9.7 | |
|
| Hardware: |
Other | |
|
| OS: |
Windows (All) | |
|
| Whiteboard: |
|
|
i915 platform:
|
|
i915 features:
|
|
|---|
| Attachments: |
Proposed fix
|
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Created attachment 35646 [details] Proposed fix Note: This was mistakenly logged as pango bug #615909 - see there for the test program. Running the test program gives this output: $ ./textsize.exe ON MINGW32_NT-5.0 LOTUS 1.0.11(0.46/3/2) 2009-07-11 17:46 i686 Msys Cairo version: 1.8.8 Pango version: 1.26.2 Hint metrics set to: ON Font: 'arial 12px' Layout text: 'The origin of thinking is some perplexity, confusion or doubt.' Ink extents: (0,3) 326x11 Logical extents: (0,0) 327x15 $ ./textsize.exe OFF MINGW32_NT-5.0 LOTUS 1.0.11(0.46/3/2) 2009-07-11 17:46 i686 Msys Cairo version: 1.8.8 Pango version: 1.26.2 Hint metrics set to: OFF Font: 'arial 12px' Layout text: 'The origin of thinking is some perplexity, confusion or doubt.' Ink extents: (0,3) 326x11 Logical extents: (0,0) 327x15 The logical extents are unaffected by the cario hint metrics font option setting on win32. According to Behdad Esfahbod, this is a known problem on win32, where hint metrics is stuck at CAIRO_HINT_METRICS_ON (whereas on OS X it is stuck at CAIRO_HINT_METRICS_OFF). This is significant because turning off hint metrics is a useful way to ensure consistent layout sizes cross-platform, which is a requirement for cross-platform diagramming applications. The problem looks to be a typo in cairo-win32-font.c, comparing CAIRO_HINT_METRICS_OFF against options.hint_style, rather than options.hint_metrics. Once fixed with the attached patch the backend looks to do the Right Thing (and is a useful reminder for me that C enums are macros in drag!). best, Richard. PS. And I'll take the opportunity here to thank everyone responsible for cairo. I am no expert on such libraries, but I have found it a pleasure to understand and to use due to the clear separation of concerns, the elegant and powerful interface, and the largely impeccable documentation to boot.