SDL blits, OpenGL, pthreads

SDL Development
1

Someone asked about OpenGL clearing:

then the dumb thing clears all 800x600 pixels of my sdl window. It says
in the redbook that OPENGL only clears the viewport portion… Is this
an SDL problem? Is there a work around?

Not all OpenGL implementation do like the redbook says. You could try
using glScissors() and glEnable( SCISSOR_TEST ), that helped me when
I had similar problem.

Someone answered me about pthreads problem:

It’s exactly what it says. Make sure you have read/write permissions to
/dev/dsp for that user, or try running the program as root. If you still
get that error, make sure some other process hasn’t opened the soundcard
and left it open (esd is a good culprit, etc.)

Does not seem to be problem with /deb/dsp. That message was generated
because I am using remote linux machine through vnc, and only console
users get right to use /dev/dsp here in my university.

…
(gdb) set args -noaudio
(gdb) run

Starting program: /tmp/tksuoran/Teddy/TeddyRelease/./Teddy -noaudio

warning: Unable to find dynamic linker breakpoint function.
GDB will be unable to debug shared library initializers
and track explicitly loaded dynamic code.

Program received signal SIG32, Real-time event 32.
0x2ae8b682 in sigsuspend () from /lib/libc.so.6

(gdb) bt

#0 0x2ae8b682 in sigsuspend () from /lib/libc.so.6
#1 0x2ade8bc0 in pthread_setconcurrency () from /lib/libpthread.so.0
#2 0x2ade80fb in pthread_create () from /lib/libpthread.so.0
#3 0x2adb94df in SDL_SYS_CreateThread (thread=0x81b9cb0, args=0x81b9fd0)
at SDL_systhread.c:99
#4 0x2adb9378 in SDL_CreateThread (fn=0x2adba1ec , data=0x0) at SDL_thread.c:252
#5 0x2adba258 in SDL_SYS_TimerInit () at SDL_systimer.c:206
#6 0x2adb9c8e in SDL_TimerInit () at SDL_timer.c:90
#7 0x2ad837f3 in SDL_InitSubSystem (flags=1048609) at SDL.c:106
#8 0x2ad8386f in SDL_Init (flags=1048609) at SDL.c:157
#9 0x8051a36 in main_cpp (argc=2, argv=0x7ffffa04) at teddy.cpp:133
#10 0x8051c85 in main (argc=2, argv=0x7ffffa04) at teddy.cpp:152

I still get the same error. What is this?

– Timo Suoranta – @Timo_K_Suoranta –

2

Program received signal SIG32, Real-time event 32.
0x2ae8b682 in sigsuspend () from /lib/libc.so.6

(gdb) bt

#0 0x2ae8b682 in sigsuspend () from /lib/libc.so.6
#1 0x2ade8bc0 in pthread_setconcurrency () from /lib/libpthread.so.0
#2 0x2ade80fb in pthread_create () from /lib/libpthread.so.0

I still get the same error. What is this?

Your gdb hasn’t been built with proper thread support for your system.

See ya,
-Sam Lantinga, Software Engineer, Blizzard Entertainment

3

Timo K Suoranta wrote:

(gdb) bt

Instead, try ‘cont’ or ‘handle 32 nostop’.

GDB is stopping the program because it doesn’t understand the signal
that your process got. But that doesn’t mean your program won’t be
able to handle it.

-Pat

Pat Tullmann @Patrick_Tullmann
If Gates got a dime each time Windows crashed… Oh, nevermind…