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Graphics issues on Raspberry Pi


In a user reports about issues with TAChart on a Raspberry Pi. Since I don't have this device I asked him to further investigate. It turns out that the graphics unit seems to have several deficiencies on this device/OS (Raspbian OS). As a test vehicle add a TPaintbox to a form and attach this OnPaint handler:

--- Code: Pascal  [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---procedure TForm1.PaintBox1Paint(Sender: TObject);begin  with Paintbox1.Canvas do begin    Pen.Style := psSolid;    Pen.Color := clBlue;    Pen.Width := 3;    Line(0, 0, Paintbox1.Width, Paintbox1.Height);    Pen.Width := 1;    Line(0, Paintbox1.Height, Paintbox1.Width, 0);  end;end;The user only sees the thin line running from bottom-left to top-right. In other experiments he found that Canvas.Pen.Style can only be psSolid,  psPattern and psInsideFrame.

Is anybody else seeing these issues?

Is anybody else using TAChart on a Raspi? Is it running correctly? The user refers to the demo programs which come with Lazarus (they run fine on Windows and Linux Mint (qt/gtk2)).

I only see this when using SSH or Xserver client. Native Raspberry Pi (I have 2 and 3) with a straight connection to a monitor doesn't have this problem. (AFAIK) I am only using the HDMI interface, though.
If someone uses I2C or similar, plz give us some insight?


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