wasm: support setting the font DPI from JS

We have not really been able to determine what the
default DPI should be, so make it configurable with
API on qtloader.js:

  qtLoader.setFontDpi(72);

Also lowers the default DPI to the standard value of
96 (down from Qt default 100).

Task-number: QTBUG-75510
Change-Id: Ica1164c8d80bb06519233adebf2c9e400c0991ce
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/plugins/platforms/wasm/qwasmintegration.h b/src/plugins/platforms/wasm/qwasmintegration.h
index 11d8d0f7f5..6bd2f857db 100644
--- a/src/plugins/platforms/wasm/qwasmintegration.h
+++ b/src/plugins/platforms/wasm/qwasmintegration.h
@@ -81,6 +81,7 @@ public:
     void addScreen(const QString &canvasId);
     void removeScreen(const QString &canvasId);
     void resizeScreen(const QString &canvasId);
+    void updateDpi();
 
 private:
     mutable QWasmFontDatabase *m_fontDb;
@@ -89,6 +90,7 @@ private:
 
     QHash<QString, QWasmScreen *> m_screens;
     mutable QWasmClipboard *m_clipboard;
+    qreal m_fontDpi = -1;
     static QWasmIntegration *s_instance;
 };