Bitmap for Retina hi-res

[AlexTP]

Hi

If I run my app on Mac, Retina, then copying TBitmap to panel (atsynedit is panel),
gives not ok result. Bitmap has usual dpi.
Panel canvas has retina dpi.
Bitmap paints not in hi res, not sharp.
TextOut on panel canvas==> text sharp
TextOut on bitmap + copy to panel canvas==> not sharp

What to do here? how to make bitmap "hi-res"? if I cannot paint on panel's canvas.

[derek.john.evans]

Maybe post screenshots of the sharp/non sharp versions.

The only thing I can think of is a difference in TFont Quality.

http://lazarus-ccr.sourceforge.net/docs/lcl/graphics/tfont.quality.html

[AlexTP]

You dont understand the Retina. retina video mode has same 1024x768(example)
but DPI is much bugger, 2x or 3x. App sees same screen size. It makes same font size. e.g. font size=12.
TextOut on Form makes hi-res font. sharp.
TextOut on bitmap ++ copy to form (GUI) makes low-res font.

[ps]

I have same problem :
http://forum.lazarus.freepascal.org/index.php/topic,33215.0.html

Painting on Form.Canvas with TBitmap is scaled (by DPI). Can't paint 1px to 1px

[circular]

You need to use a high resolution bitmap. To know the scaling factor use TControl.GetCanvasScaleFactor. Then do a stretch draw.
https://wiki.lazarus.freepascal.org/Cocoa_DPI