<div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">To add from the documentation</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">> void QFont::setStyleName(const QString &styleName)</div><span class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">> </span>Sets the style name of the font to styleName. When set, other style properties like style() and weight() will be ignored for font matching, though they may be simulated afterwards if supported by the platform's font engine.<br><div><span class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">> </span>Due to the lower quality of artificially simulated styles, and the lack of full cross platform support, it is not recommended to use matching by style name together with matching by style properties</div><div><br></div><div><div style="font-family:arial,helvetica,sans-serif;font-size:small" class="gmail_default">By using the "Bold" style, you are preventing the "Bold Italic" style to be matched, instead the italic is simulated by making it oblique. So either always replace the style name or only use style flags.<br></div><br></div></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Fri, Jan 10, 2025 at 11:55 AM Charles <<a href="mailto:peacech@gmail.com">peacech@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">>
you're getting a named style from the variable font file <br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">You didn't mention that you are using the variable font. I didn't use the variable font instead I use the static fonts. I also got the thin oblique font with the variable fonts.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">These codes works for me:</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">1. f = QFont('Exo', 24, 700, True) # use QFont specifying weight and italic</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">2. f = QFont('Exo', 24); f.setWeight(700); f.setItalic(True)</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">3. f = QFontDatabase('Exo', 'Bold', 24); f.setStyleName('Bold Italic')</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">Note that italic is part of the style name. If you call setItalic(True) there is a mismatch between the style flags and the style name. So if you use QFontDatabase and style name always use setStyleName to change the style, otherwise use QFont and setWeight and setItalic.<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Jan 10, 2025 at 11:36 AM John Sturtz <<a href="mailto:john@sturtz.org" target="_blank">john@sturtz.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><div><div>Hi again Maurizio.</div><div><br></div><div>First and foremost, thanks again for your input; I always appreciate it. (I checked back in my mail archive, and I have responses from you dating back to Feb 2019; you've been helping me for a long time. 😊) Also thanks to Charles, who chimed in as well.</div><div><br></div><div>Apparently, the code I posted worked for Charles. He didn't add Exo to the Windows system, but added it to the PyQt app with <font face="Consolas">QFontDatabase.addApplicationFont()</font>. I tried it that way, but it still behaved oddly for me. We are using the same Qt version (6.8.1). He said he has Win10, while I have Win11. Not sure whether that would matter.</div><div><br></div><div>I've been playing around with this for a few days now, trying to get my head around it. The post you linked regarding the changes in 6.7 helped with my understanding a lot. I think I get where <font face="Consolas" size="3" style="font-size:16px">QFontDatabase</font> gets its style names now. As Charles pointed out, when you request an italic font style (as reported by <font face="Consolas" size="3" style="font-size:16px">QFontDatabase</font>), you're getting a named style from the variable font file, whereas if you use <font face="Consolas" size="3" style="font-size:16px">.setItalic()</font>, you're getting something else (Charles called it 'synthesized italic'). There is even a comment in the Qt documentation for <font face="Consolas" size="3" style="font-size:16px">QFont.setStyleName()</font> that seems to explicitly discourage mixing the two:</div><div><br></div><div><a href="https://doc.qt.io/qt-6/qfont.html#setStyleName" target="_blank">https://doc.qt.io/qt-6/qfont.html#setStyleName</a></div><div><i>Due to the lower quality of artificially simulated styles, and the lack
of full cross platform support, it is not recommended to use matching by
style name together with matching by style properties</i></div><div><br></div><div>The setup I have is about as 'clean' as it can get. I got this laptop just about a month ago, and it doesn't have a lot on it that didn't ship with it. Exo is literally the only font I have installed beyond what came with Win11.</div><div><br></div><div>I see the problem with other fonts as well -- Bahnschrift, for example, which comes with Windows. If I create a <font face="Consolas" size="3" style="font-size:16px">QFont</font> object with <font face="Consolas" style="font-size:16px" size="4">QFontDatabase.font()</font><font size="3" style="font-size:16px">:</font></div><div style="font-size:16px"><br></div><div><font face="Consolas" size="3" style="font-size:16px"> f = QFontDatabase.font('Bahnschrift', 'Condensed', 24)
</font></div><div><br></div><div>and then apply <font face="Consolas" size="3" style="font-size:16px">.setItalic(True</font><font face="Consolas" size="3" style="font-size:16px">)</font> to it, it's italic, but no longer Condensed.</div><div><br></div><div>And actually, the same thing happens if I create the font with <font face="Consolas" size="3" style="font-size:16px">QFont()</font> directly:</div><div><br></div><div><font face="Consolas" size="3" style="font-size:16px"> f = QFont(
</font></div><div><font face="Consolas" size="3" style="font-size:16px"> 'Bahnschrift Condensed',
</font></div><div><font face="Consolas" size="3" style="font-size:16px"> pointSize=24
</font></div><div><font face="Consolas" size="3" style="font-size:16px"> )
</font></div><div style="font-size:16px"><br></div><div>Here also, the font is fine initially, but after <font face="Consolas" size="3" style="font-size:16px">.setItalic(True)</font> it is no longer Condensed.</div><div><br></div><div>The Bahnschrift file doesn't appear to have any italic styles defined, so there's no way to ask for italic by style name. Simulated/synthesized seems to be the only way to get italic Bahnschrift Condensed. With the setup I have, it doesn't seem to be possible at all. (The code above works as expected in PyQt5).</div><div><br></div><div>Anyway, probably a Qt issue, as you say, and one I'll just have to work around ...</div><div><br></div><div>Thanks again!</div><div><br></div><div>/John</div><div><br></div><div><br></div>
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<div>------ Original Message ------</div>
<div>From "Maurizio Berti" <<a href="mailto:maurizio.berti@gmail.com" target="_blank">maurizio.berti@gmail.com</a>></div>
<div>To "John Sturtz" <<a href="mailto:john@sturtz.org" target="_blank">john@sturtz.org</a>></div>
<div>Cc <a href="mailto:pyqt@riverbankcomputing.com" target="_blank">pyqt@riverbankcomputing.com</a></div>
<div>Date 1/5/2025 10:11:01 PM</div>
<div>Subject Re: QFontDatabase/QFont question</div></div><div><br></div>
<div id="m_-2520850084891264570m_1034062165767428918x06004e79b90744b"><blockquote cite="http://CAPn+-XSr38XMuiRxNJ1j6hFHM7rwMva2Eyw=Dfr-tv0e58vv6Q@mail.gmail.com" type="cite">
<div dir="ltr"><div>First of all, this almost certainly is a Qt issue, not a PyQt one.</div><div>Then, you have to consider at least the following aspects:</div><div><br></div><div><div>- font management and rendering is a quite complex aspect, and its results may change <b>a lot</b> depending on the platform;</div>- fonts are not always consistent, depending on many aspects;</div><div>- font matching follows arbitrary rules (some of which are based on text matching of families or properties);<br></div><div>- the [infamous] 6.7 version introduced many changes and related bugs/inconsistencies, including font management, which got important changes (see <a href="https://www.qt.io/blog/text-improvements-in-qt-6.7" target="_blank">this related post</a>);</div><div>- if you have many fonts installed, the font matching algorithm may have issues especially if you installed different versions of the "same" font (start by checking how many fonts you've installed that match the "exo" family name); using installed fonts along with ones added through QFontDatabase may further complicate things;<br></div><div><br></div><div>My suggestion is to check again with a *clean* setup (possibly through multiple VMs, OSs and configurations) and eventually consider filing a detailed report on <a href="https://bugreports.qt.io" target="_blank">https://bugreports.qt.io</a>.</div><div><br></div><div>Regards,</div><div>MaurizioB<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Il giorno lun 6 gen 2025 alle ore 00:09 John Sturtz <<a href="mailto:john@sturtz.org" target="_blank">john@sturtz.org</a>> ha scritto:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>
<div>Hi again.<div><br></div><div>Wondering if anyone can help me understand this behavior that, to me, is unexpected.</div><div><br></div><div>I'm using <font face="Consolas">QFontDatabase</font> to manipulate system fonts. Mostly it seems to work great, and behaves as I expect. I especially like its handy <font style="font-size:16px" size="3" face="Consolas">.font()</font> method, that returns a <font face="Consolas"><font style="font-size:16px" size="3">Q</font>Font</font><font style="font-size:16px" size="3"> </font>object.</div><div><br></div><div>But in this instance, it's behaving in a way I don't understand. I'm working with a Google font named Exo (<a href="https://fonts.google.com/specimen/Exo" style="font-size:12pt" target="_blank">https://fonts.google.com/specimen/Exo</a>), which I've installed on my system. <font style="font-size:16px" size="3" face="Consolas">QFontDatabase.styles('Exo')</font> produces several (18, to be exact) styles. Screenshot from Windows Font Settings below:</div><div><br></div><div style="text-align:center"><img src="cid:ii_19439be45f5a21f621b1" style="width: 474px; height: 608px;" width="374" height="480" border="0"></div><div><br></div><div>Now what I want to do is create a <font style="font-size:16px" size="3" face="Consolas">QFont</font> object of the 'Bold' style, and then just make it Italic. For example:</div><div><br></div><blockquote style="margin:0px 0px 0px 40px;border:medium;padding:0px"><div><font style="font-size:16px" size="3" face="Consolas">font = QFontDatabase.font('Exo', 'Bold', 24)</font></div><div><font style="font-size:16px" size="3" face="Consolas">font.setItalic(True)</font></div></blockquote><div><br></div><div>But after the <font style="font-size:16px" size="3" face="Consolas">.setItalic()</font> call, the font object is no longer Bold anymore (it's Thin, the lightest weight of the Exo fonts).</div><div><br></div><div>Sample code is attached (I guess one would have to install the Exo font to test it). Basically, I get the font with <font style="font-size:16px" size="3" face="Consolas">QFontDatabase.font()</font>, get and display <font style="font-size:16px" size="3" face="Consolas">QFontInfo</font> data for it, and it's what I expect. Then I get the same font again, call <font style="font-size:16px" size="3" face="Consolas">.setItalic(True)</font> on it, display <font style="font-size:16px" size="3" face="Consolas">QFontInfo</font>, and it's <i>not</i> what I expect:</div><div><br></div><div style="text-align:center"><img src="cid:ii_19439be45f7f5278d592" style="width: 530px; height: 203px;" width="640" height="245" border="0"></div><div><br></div><div>I do (sort of) understand that the object returned by <font style="font-size:16px" size="3" face="Consolas">QFont</font> is <i>requested, </i>and <font style="font-size:16px" size="3" face="Consolas">QFontInfo</font> tells you what you actually got. Apparently I didn't get what I requested, but I'm not quite sure why.</div><div><br></div><div>As always, thanks in advance if you can shed any light on this!</div><div><br></div><div>/John</div></div></div></blockquote></div><div><br clear="all"></div><br><span class="gmail_signature_prefix">-- </span><br><div dir="ltr" class="gmail_signature">È difficile avere una convinzione precisa quando si parla delle ragioni del cuore. - "Sostiene Pereira", Antonio Tabucchi<br><a href="http://www.jidesk.net" target="_blank">http://www.jidesk.net</a></div>
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