Hi
i use a PBO approach to grab a bitmap from my 3d scene . steps are the following :
glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, pbo1);
glReadPixels(0, 0,bWIDTH,bHEIGHT,GL_BGRA, GL_UNSIGNED_BYTE, 0);
copymem(glMapBufferARB(GL_PIXEL_PACK_BUFFER_ARB,GL_READ_ONLY_ARB)^, buffer,BWidth * BHeigh * 4);
glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, pbo2);
glReadPixels(0, 0,pWIDTH,pHEIGHT ,GL_BGRA, GL_UNSIGNED_BYTE, 0);
copymem(glMapBufferARB(GL_PIXEL_PACK_BUFFER_ARB, GL_READ_ONLY_ARB)^,bitmapbuf, bWidth * bHeigh * 4);
glUnmapBufferARB(GL_PIXEL_PACK_BUFFER_ARB);
swap(pbo1,pbo2)
with methode i get 15~25 fps low than a direct :
glReadPixels(0, 0,pWIDTH,pHEIGHT ,GL_BGRA, GL_UNSIGNED_BYTE, bitmapbuf);
as i see in many forum the PBO should be more Faster than the glReadPixels one :eek:
my card is : nVidia Geforce 7600 GS
forceware version : 169.21
Bus PCI Express x16
CPU : P4 3.0Ghz
are there any bad implementation in my PBO code, how can i boost it ?
help please
Thanks in Advance