AlertWindow and DialogWindow won't scale and center after setGlobalScaleFactor or when JUCE_WIN_PER_MONITOR_DPI_AWARE disabled

General JUCE discussion
1

AlertWindow and DialogWindow won’t scale and center after setGlobalScaleFactor or when JUCE_WIN_PER_MONITOR_DPI_AWARE disabled.

i’m using juce 6.1.1 on windows.

I created a new project (standalone audio application) to reproduce.

MainComponent constructor

    addAndMakeVisible(m_btn);
    m_btn.setButtonText("OPEN DIALOG");
    m_btn.onClick = [this] {

    juce::DialogWindow::LaunchOptions o;      
    o.content.setOwned(new TestComponent());
    o.content->setSize(460, 300);
    o.dialogTitle = "Dialog test";
    o.dialogBackgroundColour = o.content->getLookAndFeel().findColour(juce::DocumentWindow::backgroundColourId);
    o.escapeKeyTriggersCloseButton = true;
    o.useNativeTitleBar = false;
    o.resizable = false;
    o.componentToCentreAround = this;
    
    o.launchAsync();

};

Result : dialog is centered.

image
image1037×816 18.6 KB

Now in the app constructor i add :
juce::Desktop::getInstance().setGlobalScaleFactor(1.5f);

Result:

image
image1225×903 20.5 KB

Now JUCE_WIN_PER_MONITOR_DPI_AWARE is disabled and setGlobalScaleFactor removed.

Result:

image
image1025×817 14.5 KB

Am i doing something wrong ?

2

Looks like when JUCE_WIN_PER_MONITOR_DPI_AWARE is disabled ,
Desktop::getInstance().getGlobalScaleFactor() returns the system set scale which in my case is 1.25 (125%).
However AlertWindow and DefaultDialogWindow desktopScale member get set to 1.0f.

Those patches seem to resolve the issue.

juce_AlertWindow.cpp (Line : 39)

AlertWindow::AlertWindow (const String& title,
                          const String& message,
                          MessageBoxIconType iconType,
                          Component* comp)
   : TopLevelWindow (title, true),
     alertIconType (iconType),
     associatedComponent (comp),
#if JUCE_WIN_PER_MONITOR_DPI_AWARE
     desktopScale (comp != nullptr ? Component::getApproximateScaleFactorForComponent (comp) : 1.0f)
#else
    desktopScale (Desktop::getInstance().getGlobalScaleFactor())

#endif
{
    setAlwaysOnTop (juce_areThereAnyAlwaysOnTopWindows());

    accessibleMessageLabel.setColour (Label::textColourId, Colours::transparentBlack);
    addAndMakeVisible (accessibleMessageLabel);

    if (message.isEmpty())
        text = " "; // to force an update if the message is empty

    setMessage (message);

    AlertWindow::lookAndFeelChanged();
    constrainer.setMinimumOnscreenAmounts (0x10000, 0x10000, 0x10000, 0x10000);
}

juce_DialogWindow.cpp (Line : 79)

  DefaultDialogWindow (LaunchOptions& options)
        : DialogWindow (options.dialogTitle, options.dialogBackgroundColour,
                        options.escapeKeyTriggersCloseButton, true,
#if JUCE_WIN_PER_MONITOR_DPI_AWARE
                        options.componentToCentreAround != nullptr
                            ? Component::getApproximateScaleFactorForComponent (options.componentToCentreAround)
                            : 1.0f)
#else
        Desktop::getInstance().getGlobalScaleFactor())
#endif
    {
        setUsingNativeTitleBar (options.useNativeTitleBar);
        setAlwaysOnTop (juce_areThereAnyAlwaysOnTopWindows());

        if (options.content.willDeleteObject())
            setContentOwned (options.content.release(), true);
        else
            setContentNonOwned (options.content.release(), true);

        centreAroundComponent (options.componentToCentreAround, getWidth(), getHeight());
        setResizable (options.resizable, options.useBottomRightCornerResizer);
    }

juce_TopLevelWindow.cpp (Line : 290)

void TopLevelWindow::centreAroundComponent (Component* c, const int width, const int height)
{
    if (c == nullptr)
        c = TopLevelWindow::getActiveTopLevelWindow();

    if (c == nullptr || c->getBounds().isEmpty())
    {
        centreWithSize (width, height);
    }
    else
    {
#if JUCE_WIN_PER_MONITOR_DPI_AWARE
        auto targetCentre = c->localPointToGlobal (c->getLocalBounds().getCentre()) / getDesktopScaleFactor();
#else
        auto targetCentre = c->localPointToGlobal (c->getLocalBounds().getCentre());

#endif
        auto parentArea = c->getParentMonitorArea();

        if (auto* parent = getParentComponent())
        {
            targetCentre = parent->getLocalPoint (nullptr, targetCentre);
            parentArea   = parent->getLocalBounds();
        }

        setBounds (Rectangle<int> (targetCentre.x - width / 2,
                                   targetCentre.y - height / 2,
                                   width, height)
                     .constrainedWithin (parentArea.reduced (12, 12)));
    }
}
3

Thanks for reporting. I’ve pushed a fix for this to the develop branch here:

4

while this commit seems to fix standalone exe’s on Windows,
I still experience a similar issue with vst3 and vst2 plugins.

The following is a juce AudioPluginDemo with a new button which toggles the juce desktop scaling factor between 1.0 and 1.5 and another one showing a simple alert. The alertwindow appears to scale somewhat, yet looks still too small to me in both cases?

scalingbug
scalingbug1799×1763 155 KB

note this is the latest develop branch of today

I’m running Windows 10 on a macbook pro with retina display. The Windows HDPI desktop scaling factor is set to 200%. And indeed the alert seems to be about half the size we would expect?

PS: PM me if you’d like the code

5

In a plug-in you’ll need to associate the auxiliarlly desktop window with your editor component since this has a scale factor that has been set by the host, which may not correspond to the desktop scale factor. You can do this via the associatedComponent parameter for AlertWindows.

6

The problem seem that child windows do not get desktopscale factor. there is a simular thread. here . and the result is Use font and size from DAW in juce popup menus? - #23 by getdunne

I think it is very usefull that all child windows that are create from a parent window have the same desktop scale factor

7

You can do this via the associatedComponent parameter for AlertWindows.

thanks @ed95, that worked! (could only test now…)

  • associatedComponent parameter did the trick for juce::AlertWindow ctor
  • also, the componentToCentreAround parameter was needed for juce::DialogWindow::showModalDialog()
8

Hello
is it possible to easy add code, that juce is able to open all child windows of a plugin with the current windows desktop scale factor ?. because currently desktop scale-factor does not get propagated to new juce::DocumentWindow based windows created by a JUCE-based plug-in for example additional preference windows or popup menu windows