architecture - GLSL multiple shaderprogram VS uniforms switches -


i'm working on shader manager architecture , have several questions more advanced people. current choice oppose 2 designs are:


1. per material shader program

=> create 1 shader program per material used in program.

potential cons:

  • considering every object might have own material, involves lot of gluseprogram calls.
  • implies creation of lot of shaderprogram objects.
  • more complex architecture #2.

pros:

  • shader code can generated each "options" used in material.
  • if i'm not wrong, uniforms have set 1 time (when shaderprogram created).


2. global shader programs

=> create 1 shader program per shader functionality (lightning, reflection, parallax mapping...) , use configuration variables enable or discard options depending on material render.

potential cons:

  • uniforms have changed many times per frame.

pros:

  • lower shader programs count.
  • less sp swich (gluseprogram).


you might notice current tendency #1, wanted know opinion it.

  • does initial uniforms setting offset gluseprogram call overhead (i'm not speed freak) ?
  • in case #1, memory or performance consideration, should call gllinkprogram once when create sp, or must unlink/link each time call gluseprogram?
  • are there better solutions ?

thanks!

let's @ #1:

considering every object might have own material, involves lot of gluseprogram calls.

this isn't big of deal, really. swapping programs hard, you'd swapping textures too, it's not you're not changing important state.

implies creation of lot of shaderprogram objects.

this going hurt. indeed, main problem #1 explosive combination of shaders. while arb_separate_program_objects help, still means have write lot of shaders, or come way not write lot of shaders.

or can use deferred rendering, helps mitigate this. among many advantages separates generation of material data computations transform material data light reflectance (colors). because of that, have far fewer shaders work with. have set of shaders produces material data, , set uses material data lighting computations.

so use #1 deferred rendering.


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