[Matplotlib-devel] Internals of smooth plotting in matplotlib

[Dmitri Priimak]

Hi All.

I am writing plotting library in Scala (https://github.com/priimak/splot
https://splot-web.github.io/) but I am having difficulty doing smooth
plotting when I have a lot of data points. Consider a following use case.
Let say along the x-axis I have array of points from 0 to 0.3 with step
0.001 and on y-axis each corresponding point is computed from some
function, let say sin(x). Now I want to plot smooth plot using these
points. If I just plot corresponding pixels I might have wholes in the
image if I zoom in, so that it is not good. If I just poly line (there is
such function in java Graphics2D object) based on these points I have
another problem. I have to convert each point into onscreen pixel
coordinates (I can use floor(..) or rounding to the nearest int when doing
it). And that results in jagged step like line that  you can see here

https://i.imgur.com/t26WDut.png

That does not happen in matplotlib when let say using fig.plot(...)
function. Output is always smooth which is what I want as well. Is there a
particular place in code where I can see how that is done?

--
Dmitri Priimak
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