c++ - Drawing continuously in drawing application -

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i wondering how drawing applications draw entire time mouse down without having empty gaps. mean is, example if program drew circles @ mouse's x, y coordinate, if mouse went quicly seem bunch of little circles rather nice continuous line. how can done without drawing short straight line between mouse 0.001 seconds ago , mouse is. thanks

it can't done without drawing line between current mouse point , previous point, why drawing programs do do.

fancier drawing programs fit curvy lines multiple previous points achieve more natural drawing stroke, principle same.

update: based on comment, appears have timer involved in drawing code. surely unnecessary, since application generate mousemove event whenever mouse moved @ all, , can use event draw next line.


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