Dpi --> ppi

[WojTec]

How to compute selected printer PPI if I know DPI?

GetDeviceCaps(Printer.Handle, LOGPIXELSY) I checked what is PPI and don't understand. Need diagonal resolution in inches and size (w/h) of what - paper?, image?

[himitsu]

GetDeviceCaps

Zitat von LOGPIXELSX:

Number of pixels per logical inch along the screen printer width

printer = printhead = paper

[WojTec]

I don't know I have this and don't have idea how to compute it

Delphi-Quellcode:

var
  dp, ppi: Int32;
  di: Int32;
begin
  ShowMessage(Format('%dx%d'#13#10'%dx%d'#13#10'%dx%d'#13#10'%dx%d', [
    PrintPreview1.PageSize.X, PrintPreview1.PageSize.Y,
    PrintPreview1.PageDevicePixels.X, PrintPreview1.PageDevicePixels.Y,
    PrintPreview1.PageLogicalPixels.X, PrintPreview1.PageLogicalPixels.Y,
    Printer.PageWidth, Printer.PageHeight
  ]));

  dp := Round(Sqrt(Sqr(PrintPreview1.PageDevicePixels.X) + Sqr(PrintPreview1.PageDevicePixels.Y)));
  di := Round(Sqrt(Sqr(PrintPreview1.PageDevicePixels.X div GetDeviceCaps(PrintPreview1.Printer.Handle, LOGPIXELSX)) + Sqr(PrintPreview1.PageDevicePixels.Y div GetDeviceCaps(PrintPreview1.Printer.Handle, LOGPIXELSY))));
  ppi := dp div di;
  ShowMessage(IntToStr(dp div (dp div 96)));
end;