iOS touch frame rate

Question

I'm doing this iOS app, where a user drags his finger over the screen of his iPhone along a circular path. During this action, the app plots little dots every other millimeter, effective creating a dotted line along the path. This works fine, as long as the user draws slowly. If he however drags his finger faster, the app is not able to draw a dot at every location on the path, leaving undesired gaps. What would be a good approach to compensate for this phenomenon? Thanks ahead

Answer 1

Instead of drawing dots, draw lines (line starts at the last dot, and finishes at the new dot). This way if the user draws slowly you will get the same effect, but if he draws quickly you will not have gaps.

Answer 2

通过此操作，它应该可以帮助http://mobile.tutsplus.com/tutorials/iphone/ios-sdk-advanced-freehand-drawing-techniques/