Virtual function APIs have to be designed such that they don't suffer from lack of inlining.
E.g. if you're making a graphics display driver, don't have objref->putpixel(x, y) as your only virtual function, which has to be called thousands of times to draw a line or millions to fill an area.
E.g. if you're making a graphics display driver, don't have objref->putpixel(x, y) as your only virtual function, which has to be called thousands of times to draw a line or millions to fill an area.