Text engine for OpenGL renderer

[Ben Abbott]

On Jun 28, 2009, at 2:13 PM, Thomas Treichl wrote:

> Shai Ayal schrieb:
>> On Sat, Jun 27, 2009 at 4:09 PM, Thomas Treichl<Thomas.Treichl at gmx.net 
>> > wrote:
>>> Can somebody please give a short Octave code example how I can  
>>> check if text
>>> rendering works or not after the inclusion of fontconfig into my  
>>> binary (how
>>> does it look like - I'm no plotting expert).
>>>
>>> Thanks,
>>> Thomas
>> backend("fltk")
>> plot(1:10)
>> and see if the axis labels appear. you can than try "title",  
>> "xlabel", etc ...
>> Shai
>
> Your example works and the axis labels appear on my Mac OS X 10.4  
> system. But this only works once, if I call "plot", "xlabel" or  
> "title" as a second command then Octave crashes. Here is what I mean  
> by example:
>
>  octave-3.2.0:1> backend ("fltk")
>  octave-3.2.0:2> plot (1:10) # does work very well
>  octave-3.2.0:3> plot (1:10)
>  octave-3.2.0:4> error: could not match any font: *-normal-normal-12
>  error: unable to load font:
>  error: ft_render: unable to load appropriate font
>  panic: Segmentation fault -- stopping myself...
>  attempting to save variables to `octave-core'...
>  save to `octave-core' complete
>
> In debug mode I can reproduce the following output:
>
> octave:1> backend ("fltk")
> Reading symbols for shared libraries .... done
> octave:2> plot (1:10) # does work very well
> octave:3> Reading symbols for shared libraries . done
> Reading symbols for shared libraries . done
> Reading symbols for shared libraries . done
> Reading symbols for shared libraries ... done
> Reading symbols for shared libraries . done
> Reading symbols for shared libraries .. done
> Reading symbols for shared libraries . done
> Reading symbols for shared libraries ....... done
> Reading symbols for shared libraries ... done
> Reading symbols for shared libraries . done
> Reading symbols for shared libraries . done
> Reading symbols for shared libraries . done
> Reading symbols for shared libraries . done
> octave:3> plot (1:10)
> octave:4> error: could not match any font: *-normal-normal-12
> error: unable to load font:
> error: ft_render: unable to load appropriate font
> Program received signal EXC_BAD_ACCESS, Could not access memory.
> Reason: KERN_INVALID_ADDRESS at address: 0xfffffffd
> 0x90b40517 in __gnu_cxx::__exchange_and_add ()
> (gdb) where
> #0  0x90b40517 in __gnu_cxx::__exchange_and_add ()
> #1  0x011be99c in input_event_hook () at basic_string.h:226
> #2  0x02ba39a6 in command_editor::event_handler () at cmd-edit.cc:877
> #3  0x00779524 in rl_read_key ()
> #4  0x007610e1 in readline_internal_char ()
> #5  0x007612d5 in readline ()
> #6  0x02ba6ca4 in gnu_readline::do_readline (this=0x364fa50,  
> prompt=@0xffffffff, eof=@0xbfffcdec) at cmd-edit.cc:255
> #7  0x02ba50e1 in command_editor::readline (prompt=@0xbfffceb4,  
> eof=@0xbfffcdec) at cmd-edit.cc:902
> #8  0x011b9a33 in gnu_readline (s=@0xbfffceb4, force_readline=false)  
> at input.cc:202
> #9  0x011b9fbe in octave_gets () at input.cc:248
> #10 0x011ba82a in octave_read (buf=0xf5000 "", max_size=8192) at  
> input.cc:347
> #11 0x011c1d4d in yy_get_next_buffer () at <stdout>:2879
> #12 0x011cdba3 in octave_lex () at <stdout>:2721
> #13 0x012aad4c in octave_parse () at parse.cc:2234
> #14 0x012fc07b in main_loop () at toplev.cc:566
> #15 0x012983df in octave_main (argc=6, argv=0xbfffda20, embedded=0)  
> at octave.cc:886
> #16 0x00006630 in main (argc=-1, argv=0xffffffff) at main.c:35
> #17 0x00005f92 in _start ()
> #18 0x00005eb9 in start ()
> (gdb)
>
> Any ideas? Thanks,
>  Thomas
>
> PS. Ben can you see this with Fink, too, or is it just my binary?

I ran a few commands below. I had no problems until "quit".

octave:2> close all
octave:3> backend ("fltk")
octave:4> plot(1:10)
octave:5> plot(1:10)
octave:6> plot(1:10)
octave:7> figure(2)
octave:8> plot(1:10)
octave:9> surf(peaks)
octave:10> ca=nan

octave:10> quit

panic: Segmentation fault -- stopping myself...
attempting to save variables to `octave-core'...
terminate called after throwing an instance of 'std::length_error'
   what():  basic_string::_S_create
panic: attempted clean up apparently failed -- aborting...

Ben