How the GetTextMetrics method gets the font metrics from a font ？

[JVS94]

I am designing a font that will be used in an RCP application for Windows. As mentioned in this article, different software and systems may use different parameters as font metrics.

org.eclipse.swt.graphics.GC.getFontMetrics() use the win32 API GetTextMetrics to converts the parameters in the font to TEXTMETRIC :

public FontMetrics getFontMetrics() {
	if (handle == 0) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	checkGC(FONT);
	TEXTMETRIC lptm = new TEXTMETRIC();
	OS.GetTextMetrics(handle, lptm);
	return FontMetrics.win32_new(lptm);
}

However, the official documentation does not specify which font internal parameters it specifically uses. Does anyone know more details?