| | [ Return to Bugs & Features | Roadmap 1.1 | SVN ⇄ GIT ]
STR #12
| Application: | FLTK Library |
|---|
| Status: | 1 - Closed w/Resolution |
|---|
| Priority: | 2 - Low, e.g. a documentation error or undocumented side-effect |
|---|
| Scope: | 2 - Specific to an operating system |
|---|
| Subsystem: | X11 |
|---|
| Summary: | gl_draw & fl_font_xft problem & fix |
|---|
| Version: | 1.1.3 |
|---|
| Created By: | jmw.micronix.com |
|---|
| Assigned To: | mike |
|---|
| Fix Version: | 1.1.4 |
|---|
| Update Notification: | |
|---|
Trouble Report Files:
No files
Trouble Report Comments:
| |
| #1 | jmw.micronix.com
06:52 Apr 12, 2003 |
| Compiling FLTK 1.1.3 with xft enabled under X11 results in gl_draw not working as the glXUseXFont() call within gl_font barfs with an Xrequest:BadFont error. (I'm using Linux 2.4.20, Xfree 4.2.0, gcc 2.95.3).
Whilst I realise that xft support is not yet complete and may be addressed properly in due course, this particular problem can be easily solved with a little hack to gl_draw.cxx and fl_font_xft.cxx. This may help others who
want to use bitmapped fonts with OpenGL scenes AND have anti-aliasing operational with FLTK 1.1.x. Not sure how valid this is but hey, it works for me.
src/fl_font_xft.cxx:
Need to make sure that listbase is set to 0 as gl_font uses this to determine whether to create bitmap display lists for the font in question so we alter Fl_FontSize to:
Fl_FontSize::Fl_FontSize(const char* name) {
encoding = fl_encoding_;
size = fl_size_;
#if HAVE_GL
listbase = 0;
#endif
font = fontopen(name, false);
}
Also need to add the following (ripped from v2.0 code).
// This call is used by opengl to get a bitmapped font.
XFontStruct* fl_xxfont() {
if (current_font->core) return current_font->u.core.font;
static XftFont* xftfont;
if (xftfont) XftFontClose (fl_display, xftfont);
xftfont = fontopen(fl_fonts[fl_font_].name, true);
return xftfont->u.core.font;
}
src/gl_draw.cxx:
Just need to add declaration for fl_xxfont() (this should go in a header but I didn't want to contaminate mine).
#if USE_XFT
extern XFontStruct* fl_xxfont();
#endif
Then we just need to add the call to fl_xxfont in the appropriate place within gl_font which becomes:
void gl_font(int fontid, int size) {
fl_font(fontid, size);
if (!fl_fontsize->listbase) {
#ifdef WIN32
int base = fl_fontsize->metr.tmFirstChar;
int count = fl_fontsize->metr.tmLastChar-base+1;
HFONT oldFid = (HFONT)SelectObject(fl_gc, fl_fontsize->fid);
fl_fontsize->listbase = glGenLists(256);
wglUseFontBitmaps(fl_gc, base, count, fl_fontsize->listbase+base);
SelectObject(fl_gc, oldFid);
#elif defined(__APPLE__)
fl_fontsize->listbase = glGenLists(256); aglUseFont(aglGetCurrentContext(),fl_fontsize->font,fl_fontsize->face,
fl_fontsize->size, 0, 256, fl_fontsize->listbase);
#else
#if USE_XFT
fl_xfont = fl_xxfont();
#endif
int base = fl_xfont->min_char_or_byte2;
int count = fl_xfont->max_char_or_byte2-base+1;
fl_fontsize->listbase = glGenLists(256);
glXUseXFont(fl_xfont->fid, base, count, fl_fontsize->listbase+base);
#endif
}
glListBase(fl_fontsize->listbase);
}
Then just recompile fltk and verify using the cube test program (fix is properly exercised if cube.cxx is hacked to draw text in different fonts/sizes). Hope this helps somebody somewhere.
Cheers!
| |
| |
| #2 | mike
14:59 May 04, 2003 |
| Thanks, these changes have been applied to CVS for the 1.1.4 release. | |
[ Return to Bugs & Features ]
|
| |
