osx-crash when activating antialiasing

Scripting Issues
1

i am trying to activate antialiasing under osx, however i get a crash when i try to activate setup the multisamples:

from pandac.PandaModules import loadPrcFileData
loadPrcFileData('', 'framebuffer-multisample 1' )
loadPrcFileData('', 'multisamples 8')

from direct.directbase import DirectStart

a = loader.loadModel( 'test.egg' )
a.reparentTo( render )

from pandac.PandaModules import *

MODEL_ANTIALIAS = AntialiasAttrib.MAuto | AntialiasAttrib.MBetter
render.setAntialias(MODEL_ANTIALIAS)

run()

without the loadprc-commands, it doesnt crash, but antialias doesnt work. Afaik those commands are required to have antialiasing.

this bug doesnt seem to be fixed in the latest dev-versions.

Process:         Python [6979]
Path:            /System/Library/Frameworks/Python.framework/Versions/2.5/Resources/Python.app/Contents/MacOS/Python
Identifier:      org.python.pythonapp
Version:         2.5.0 (2.5.0a0)
Build Info:      python-300000~42
Code Type:       X86 (Native)
Parent Process:  bash [6206]

Date/Time:       2008-09-17 15:39:21.699 +0200
OS Version:      Mac OS X 10.5.4 (9E17)
Report Version:  6

Exception Type:  EXC_BAD_ACCESS (SIGBUS)
Exception Codes: KERN_PROTECTION_FAILURE at 0x0000000000000000
Crashed Thread:  0

Thread 0 Crashed:
0   com.apple.opengl              	0x96675b93 CGLDescribePixelFormat + 83
1   com.apple.agl                 	0x9213c009 aglDevicesOfPixelFormat + 132
2   libosxdisplay.dylib           	0x049c4095 osxGraphicsStateGuardian::describe_pixel_format(FrameBufferProperties&) + 693
3   libosxdisplay.dylib           	0x049c4a2b osxGraphicsStateGuardian::buildGL(osxGraphicsWindow&, bool, FrameBufferProperties&) + 1323
4   libosxdisplay.dylib           	0x049ba962 osxGraphicsWindow::buildGL(bool) + 114
5   libosxdisplay.dylib           	0x049be6f9 osxGraphicsWindow::OSOpenWindow(WindowProperties&) + 633
6   libosxdisplay.dylib           	0x049bffa8 osxGraphicsWindow::open_window() + 312
7   libdisplay.dylib              	0x01e71589 GraphicsWindow::set_properties_now(WindowProperties&) + 121
8   libosxdisplay.dylib           	0x049bf1ba osxGraphicsWindow::set_properties_now(WindowProperties&) + 58
9   libdisplay.dylib              	0x01e7104e GraphicsWindow::process_events() + 158
10  libosxdisplay.dylib           	0x049b859a osxGraphicsWindow::process_events() + 26
11  libdisplay.dylib              	0x01e22f5c GraphicsEngine::process_events(ov_set<PointerTo<GraphicsOutput>, IndirectLess<GraphicsOutput> > const&, Thread*) + 44
12  libdisplay.dylib              	0x01e24a83 GraphicsEngine::WindowRenderer::do_windows(GraphicsEngine*, Thread*) + 67
13  libdisplay.dylib              	0x01e30cd8 GraphicsEngine::open_windows() + 104
14  libdisplay.dylib              	0x01e393ed GraphicsEngine::make_output(GraphicsPipe*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, int, FrameBufferProperties const&, WindowProperties const&, int, GraphicsStateGuardian*, GraphicsOutput*) + 925
15  libdisplay.dylib              	0x01eac5f6 Dtool_GraphicsEngine_make_output_436(_object*, _object*, _object*) + 1078
...
2

Some more info’s i’ve found:

the last panda call seems to be a deprecated call (since 10.5):
http://developer.apple.com/documentation/GraphicsImaging/Reference/AGL_OpenGL/Reference/reference.html#//apple_ref/c/func/aglDisplaysOfPixelFormat
aglDevicesOfPixelFormat is replaced by aglDisplaysOfPixelFormat

some techinfo’s on the change:
http://developer.apple.com/qa/qa2007/qa1523.html

3

Nearly all of the calls in osxdisplay are deprecated. But that shouldn’t matter. Does your graphics card support multisampling?

4

We have had to use deprecated and undocumented function calls, since the new, blessed replacement functions don’t appear to be general enough to open a window and create a graphics context on it, from within a Python process.

(If anyone with lots of Apple experience can find a better way, I’d love to hear about it.)

I’m not sure about the multisample crash. I don’t get a crash per se, but I do get this in pview:

:display(error): Could not get requested FrameBufferProperties; abandoning window.
  requested: depth_bits=1 alpha_bits=8 stencil_bits=8 multisamples=1 back_buffers=1 force_hardware=1
  got: depth_bits=24 color_bits=24 alpha_bits=8 stencil_bits=8 back_buffers=1 force_hardware=1
:display: Closing osxGraphicsWindow

And this in DirectBase:

:display(warning): FrameBufferProperties available less than requested.

Both of these are expected, since my graphics card doesn’t support multisamples.

Is it possible your graphics driver has a bug which is causing the crash when you request multisamples? Or is it something Panda is doing wrong in your case?

David

5

One thing i am yet sure about is the following call a error handling should be made:

in panda/src/osxdisplay/osxGraphicsStateGuardian.cxx:

  GLint ndevs;
  AGLDevice *gdevs = aglDisplaysOfPixelFormat(_aglPixFmt, &ndevs);
  if (gdevs != (AGLDevice *)NULL) {

from http://developer.apple.com/documentation/GraphicsImaging/Reference/AGL_OpenGL/Reference/reference.html#//apple_ref/c/func/aglDisplaysOfPixelFormat:

(sorry i’m not good enougth in c to make a patch)

drwr: maybe it doesnt crash for you because multisampling is not supported on your system?

i am pretty sure that my graphics card is able to do multisampling (RadeonX1600 on MacBook Pro) using 10.5.4.
i also get this when i set “notify-level-display debug” in the .prc

however whatever i set as “multisamples X” in the config.prc (except 0) it crashes.

6

the full output of running pview with display on debug: