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Pharo: How to increase MouseMoveEvent Frequency?

In the Pharo book there is an example for a Paint Canvas.

The problem is that the frequency in which mouse move events are passed to the handler is rather low, therefore you cannot draw continous paths if you move the mouse too quickly. Is there some way to increase the update frequency for a morph? In Squeak, there is a SketchMorphEditor which does not have that problem, but I have not figured out why yet. I am using Pharo 5.0.

Solution

  • As far as I know there is no way to increase the sampling rate. Even if it could be done, it would be a very bad idea for several reasons. First, linear interpolation yields fairly good results (which can be improved with techniques like anti-aliasing, if necessary):

    enter image description here

    Second, we cannot rely on the sampling rate to be the same on every machine and to have consistent results. And third, since I plan to use a gesture recognizer, algorithms like the $1 Recognizer do not rely on sampling rates and work surprisingly well.