performance - Opengl glLoadIdentity() faster than glPushMatrix()/glPopMatrix()? -


i make particle emitter. not need manage parent / child hierachy in transformations.

what fastest?

glpushmatrix()     ..apply tranformations     ...draw object glpopmatrix()

or

glloadidentity()     ..apply tranformations     ...draw object

for each particules ?

i tried both techniques in program not see difference in fps. few variations can come other programs on pc, such anti-virus. (i guess)

neither. if you're rendering particle system number of particles ever performance issue, sending transform each particle (which means issuing separate rendering call each particle) kill hope of performance.

if want particle system, best bet put particles in array (preferably buffer object) , render in 1 single call.


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