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wxMaxima-developers / wxmaxima

A gui for the computer algebra system Maxima built with wxWidgets
https://wxMaxima-developers.github.io/wxmaxima/
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Printing on Windows - transparency issue #1909

Closed daute closed 1 month ago

daute commented 2 months ago

The new nice sum, product and integration signs are displayed okay. But if one want's to print them (e.g. just print a PDF), they are just black boxes - only on Windows, not on Linux, there everything is okay: int-sum-prod.pdf

Seems to be an issue with transparency, there are some similar reports on the web.

Can we use other - non transparent - SVG-signs - just for printing? Inserting <rect width="100%" height="100%" fill="white" /> in the SVGs worked for the integral sign, but not for the sum and prod sign (and I don't see why). And of course it looks strange, if one chooses a non-white worksheet background, so rendering the signs just for printing non transparent would be a solution (the worksheet is printed with a white background, even if one chooses another color).

Best regards, Wolfgang

gunterkoenigsmann commented 2 months ago

Am still unsure what can possibly cause this one: The svg files don't seem to differ in any important place and they are interpreted by exactly the same code on MS Windows and on Linux. In the cross-compiled build they even use the same compiler.

Might the problem be that for one svg file the interpreter uses a transparent black background and for the other a transparent white one? As they both are transparent that should not make a difference on any OS that doesn't have a history of not properly supporting transparency in 2024.

Another thing MS Windows isn't good at is supporting different pixel formats (24 bits per pixel, 2 bit per pixel, 32 bits per pixel,...). I once changed the image format for displayed bitmaps for that reason, but in the last few years a few of my .png files have started having a black or white instead of a transparent background seemingly at random...

daute commented 2 months ago

There seem to be issues with transparency only on windows, e.g. (not sure, if that applies in our case): https://github.com/wxWidgets/wxWidgets/issues/23532 Can we 're-render' the int/sum/prod-cells for printing (maybe only on Windows), e.g. with a white background and no transparency?