opengl - Is double buffering needed any more -


as today's cards seem keep list of render commands , flush on call glflush or glfinish, double buffering needed more? opengl game developing on linux (ati mobility radeon card) sdl/opengl flickers less when sdl_gl_swapbuffers() replaced glfinish() , sdl_gl_setattribute(sdl_gl_doublebuffer,0) in init code. particular case of card or such things on cards?

edit: i've discovered cause kwin. appears datenwolf said, compositing without sync cause. when switched off kwin compositing, game works fine without source code patches

double buffering , glfinish 2 different things.

glfinish blocks program, until drawing operations completed.

double buffering used hide rendering process user. without double buffering, each , every single drawing operation become visible immediately, assuming display refresh frequency infinitely high. in practice display artifacts, parts of scene visible in 1 state, rest not visible or in other state, picture incomplete, etc. double buffering avoids first rendering buffer, , after rendering has been finished swapping front buffer, gets sent display device.

now today compositing window management becomes prevalent: windows has aero, macos x quartz extreme , on linux @ least unity , gnome3 shell use compositing if available. point is: compositing technically creates doublebuffering: windows draw offscreen buffers , of these final screen composited. if you're running on machine compositing, double buffering kind of redundant if performed in program, , it'd take kind of synchronization mechanism, tell compositor when next frame ready. macos x has this. x11 still lacks proper synchronization scheme, see post on maillist: http://lists.freedesktop.org/archives/xorg/2004-may/000607.html

tl;dr: double buffering , glfinish different things, , need double buffering (of sort) make things good.


Comments

Post a Comment

Popular posts from this blog

c# - SharpSVN - How to get the previous revision? -

i trying find efficient way previous revision of file text comparison using sharpsvn. using (svnclient c = new svnclient()) { c.authentication.defaultcredentials = new networkcredential( configurationmanager.appsettings.get("svnserviceusername") , configurationmanager.appsettings.get("svnservicepassword") , configurationmanager.appsettings.get("svnservicedomain") ); c.authentication.sslservertrusthandlers += new eventhandler<svnsslservertrusteventargs>(authentication_sslservertrusthandlers); collection<svnfileversioneventargs> fileversioncollection = new collection<svnfileversioneventargs>(); svnrevisionrange range = new svnrevisionrange(0, this.hooks.revision); svnfileversionsargs args = new svnfileversionsargs(); args.retrieveproperties = true; args.range = range; foreach (svnchangeitem item in log.changedpaths) { string path = this.repositorypath + it...
Read more

c++ - Is it possible to compile a VST on linux? -

for class project i'm attempting write vst plugin backed cuda. current cuda workflow on linux box, i'd prefer compile , link there. according wikipedia , should possible (i couldn't find steinberg documentation relevant linux) can't find makefile or instructions on how build if aren't using xcode or visual studio. i'm vst 3 sdk doesn't support linux. when try compile plugin under linux, error: ./base/source/fatomic.cpp:39:30: fatal error: libkern/osatomic.h: no such file or directory this issue caused following code in "vst3 sdk/base/source/fatomic.cpp" #if mac #include <libkern/osatomic.h> #if mac_os_x_version_min_required > mac_os_x_version_10_4 #define native_atomic_type (volatile int32_t*) #else #define native_atomic_type (int32_t*) #endif #elif windows #include <windows.h> #endif but hope compiling under linux work vst sdk 2.4. reading. jvstwrapper seems run on lin...
Read more

url - Querystring manipulation of email Address in PHP -

i using third party application (email2http) send me emailid, body , message. unable retrieve email id due name appended on , enclosed < , >. here querystring getting. test.php?from=ajay+reddy &subject=cx&body=somebody when print variable in php returns name , not email id. $from = $_get['from']; echo $from; //output ajay reddy please suggest me how can emailid also. i dont want use post method due testing , debugging. it's working fine. forgot use htmlentities() in debugging.
Read more