Fixes Ogl when resizing and dragging shapes

[hasii2011]

[
Many of the computations when resizing or moving OGL shapes result in float values. The result is that the wx.DC primitive calls fail because they expect integer values. This PR changes the computations results to become integer values, thus method calls on the wx device contexts do not fail

Most of the changes involve

• using the integer divide operator '//' instead of the float operator '/'
• In some instances I massage the results via the 'round' operator
• Additonally, I change the use of wx.RealPoint to just wx.Point
• Finally, I changed some of the float constants to integer constants
  ]

Fixes #2739

[hasii2011]

Want to get these set of changes into a daily build. If I need more patches I can work against it. I verified these changes by modifying the virtual environment I created.

[echoix]

Can you either edit the title or explain what that markup in the commit message and the PR title means?

[hasii2011]

I hope the above is clearer. Please advise

[echoix]

Couple things for the reviewers to watch for:

• The change from wx.RealPoint to wx.Point seems a bit naive for the type of fix here, it changes a big part of the meaning.
• Same thing with the overall changes in the file. Is it expected to do all intermediate calculations as integers, not just at the output? How does wxPython handle fractional scaling? The handling seems different between platforms for wxWidgets at least: https://docs.wxwidgets.org/3.2/overview_high_dpi.html
• Not fixing the line 3447 as mentioned in the thread
• Replacing a float() call with round(). Appart from changing the meaning greatly, the use of round() in the context of a graphics API surprises me. Graphics APIs usually hate off-by-one-pixel bugs, so a closer look needs to be taken to make sure the mathematical premises (assumptions) are still true after the change.