ios - check if imageview has been rotated — Objective-c -

i have imageview being rotated pi/4 (radians) every time it's taped. works fine code:

- (void)handletap:(uitapgesturerecognizer *)taprecognize { if (taprecognize == taprecognizer) {     cgaffinetransform transform = cgaffinetransformrotate(imageview.transform, (m_pi / 4));     [imageview settransform:transform]; } 

the taprecognizer asigned imageview.

now, want check if imageview has been rotated. code:

if (cgaffinetransformequaltotransform(imageview.transform, rot45)) //rot45 cgaffinetransformmakerotation variable set m_pi / 4 {     nslog("rotated"); } 

that works fine first tap, when has been rotated 45°. want able check when has been taped 2 times, means has been rotated 90°. , on. want different actions on each rotation-angle. how can check that?

sorry if question unclear

devise scheme map tag property rotation. on every rotation update tag value.