I use "LCLIntf.DrawText" for drawing text on the screen and "Canvas.TextWidth" to determine its width to increment a TRect for the next text output. But these functions cause some trouble with drawing (UTF-8-) text on Windows. In general it works okay but sometimes peculiar clipping or other pixel differences occur. Are the functions above the correct ones to draw and measure text?

After looking a bit at the code I saw that in the file "intfbasewinapi.inc" almost everywhere the Windows API function "GetTextExtentPoint" is used to determine text metrics. But
https://msdn.microsoft.com/en-us/library/windows/desktop/dd144937%28v=vs.85%29.aspx says:
"This function is provided only for compatibility with 16-bit versions of Windows. Applications should call the *GetTextExtentPoint32* <https://msdn.microsoft.com/en-us/library/windows/desktop/dd144938%28v=vs.85%29.aspx> function, which provides more accurate results."

I think many of my problems come from using this deprecated API function. Are there any plans to change this?
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If you had a look at the win32 implementation of GetTextExtentPoint then you would have seen that GetTextExtentPoint32 is used internally.

Marc

Realy?
Where do you find this?
I only find the opposite.
When I follow where Canvas.TextWidth comes from
I end up on in this function from "canvas.inc" (line 1763):

function TCanvas.TextExtent(const Text: string): TSize;
begin
Result.cX := 0;
Result.cY := 0;
if Text='' then exit;
RequiredState([csHandleValid, csFontValid]);
GetTextExtentPoint(FHandle, PChar(Text), Length(Text), Result);
end;

Even more, there is a function declaration for "GetTextExtendPoint32" but it still uses "GetTextExtendPoint" (line 1162 in "intfbasewinapi.inc"):

function TWidgetSet.GetTextExtentPoint32(DC: HDC; Str: PChar; Count: Integer; var Size: TSize): Boolean;
begin
Result := GetTextExtentPoint(DC,Str,Count,Size);
end;

TWidgetSet is the base class.
TWin32WidgetSet overrides the base class TWidgetSet.

Mattias

If you set a breakpoint and start stepping, you will see that you end up in TWin32WidgetSet. The codetools cannot jump to the real widgetset.

Marc