webkit2gtk3/webkit-font-scaling.patch

Index: webkitgtk-2.30.4/Source/WebKit/UIProcess/API/glib/WebKitSettings.cpp
===================================================================
--- webkitgtk-2.30.4.orig/Source/WebKit/UIProcess/API/glib/WebKitSettings.cpp
+++ webkitgtk-2.30.4/Source/WebKit/UIProcess/API/glib/WebKitSettings.cpp
@@ -81,7 +81,6 @@ struct _WebKitSettingsPrivate {
     CString mediaContentTypesRequiringHardwareSupport;
     bool allowModalDialogs { false };
     bool zoomTextOnly { false };
-    double screenDpi { 96 };
 #if PLATFORM(GTK)
     bool enableBackForwardNavigationGestures { false };
 #endif
@@ -176,7 +175,6 @@ enum {
 
 static void webKitSettingsDispose(GObject* object)
 {
-    WebCore::setScreenDPIObserverHandler(nullptr, object);
     G_OBJECT_CLASS(webkit_settings_parent_class)->dispose(object);
 }
 
@@ -191,23 +189,6 @@ static void webKitSettingsConstructed(GO
     bool mediaStreamEnabled = prefs->mediaStreamEnabled();
     prefs->setMediaDevicesEnabled(mediaStreamEnabled);
     prefs->setPeerConnectionEnabled(mediaStreamEnabled);
-
-    settings->priv->screenDpi = WebCore::screenDPI();
-    WebCore::setScreenDPIObserverHandler([settings]() {
-        auto newScreenDpi = WebCore::screenDPI();
-        if (newScreenDpi == settings->priv->screenDpi)
-            return;
-
-        auto scalingFactor = newScreenDpi / settings->priv->screenDpi;
-        auto fontSize = settings->priv->preferences->defaultFontSize();
-        auto monospaceFontSize = settings->priv->preferences->defaultFixedFontSize();
-        settings->priv->screenDpi = newScreenDpi;
-
-        g_object_freeze_notify(G_OBJECT(settings));
-        webkit_settings_set_default_font_size(settings, std::round(fontSize * scalingFactor));
-        webkit_settings_set_default_monospace_font_size(settings, std::round(monospaceFontSize * scalingFactor));
-        g_object_thaw_notify(G_OBJECT(settings));
-    }, object);
 }
 
 static void webKitSettingsSetProperty(GObject* object, guint propId, const GValue* value, GParamSpec* paramSpec)
Index: webkitgtk-2.30.4/Source/WebKit/UIProcess/API/glib/WebKitWebView.cpp
===================================================================
--- webkitgtk-2.30.4.orig/Source/WebKit/UIProcess/API/glib/WebKitWebView.cpp
+++ webkitgtk-2.30.4/Source/WebKit/UIProcess/API/glib/WebKitWebView.cpp
@@ -73,6 +73,7 @@
 #include <WebCore/CertificateInfo.h>
 #include <WebCore/GUniquePtrSoup.h>
 #include <WebCore/JSDOMExceptionHandling.h>
+#include <WebCore/PlatformScreen.h>
 #include <WebCore/RefPtrCairo.h>
 #include <WebCore/URLSoup.h>
 #include <glib/gi18n-lib.h>
@@ -306,6 +307,8 @@ struct _WebKitWebViewPrivate {
 
     GRefPtr<WebKitWebsiteDataManager> websiteDataManager;
     GRefPtr<WebKitWebsitePolicies> websitePolicies;
+
+    double textScaleFactor;
 };
 
 static guint signals[LAST_SIGNAL] = { 0, };
@@ -793,6 +796,15 @@ static void webkitWebViewConstructed(GOb
 
     priv->backForwardList = adoptGRef(webkitBackForwardListCreate(&getPage(webView).backForwardList()));
     priv->windowProperties = adoptGRef(webkitWindowPropertiesCreate());
+
+    priv->textScaleFactor = WebCore::screenDPI() / 96.;
+    getPage(webView).setTextZoomFactor(priv->textScaleFactor);
+    WebCore::setScreenDPIObserverHandler([webView] {
+        auto& page = getPage(webView);
+        auto zoomFactor = page.textZoomFactor() / webView->priv->textScaleFactor;
+        webView->priv->textScaleFactor = WebCore::screenDPI() / 96.;
+        page.setTextZoomFactor(zoomFactor * webView->priv->textScaleFactor);
+    }, webView);
 }
 
 static void webkitWebViewSetProperty(GObject* object, guint propId, const GValue* value, GParamSpec* paramSpec)
@@ -956,6 +968,8 @@ static void webkitWebViewDispose(GObject
     webView->priv->view->close();
 #endif
 
+    WebCore::setScreenDPIObserverHandler(nullptr, webView);
+
     G_OBJECT_CLASS(webkit_web_view_parent_class)->dispose(object);
 }
 
@@ -3600,7 +3614,7 @@ void webkit_web_view_set_zoom_level(WebK
     auto& page = getPage(webView);
     page.scalePage(1.0, IntPoint()); // Reset page scale when zoom level is changed
     if (webkit_settings_get_zoom_text_only(webView->priv->settings.get()))
-        page.setTextZoomFactor(zoomLevel);
+        page.setTextZoomFactor(zoomLevel * webView->priv->textScaleFactor);
     else
         page.setPageZoomFactor(zoomLevel);
     g_object_notify(G_OBJECT(webView), "zoom-level");
@@ -3621,7 +3635,7 @@ gdouble webkit_web_view_get_zoom_level(W
 
     auto& page = getPage(webView);
     gboolean zoomTextOnly = webkit_settings_get_zoom_text_only(webView->priv->settings.get());
-    return zoomTextOnly ? page.textZoomFactor() : page.pageZoomFactor();
+    return zoomTextOnly ? page.textZoomFactor() / webView->priv->textScaleFactor : page.pageZoomFactor();
 }
 
 /**