Fixed rare font scaling issue on Windows 10.

src/slic3r/GUI/FirmwareDialog.cpp

@@ -726,7 +726,7 @@ const char* FirmwareDialog::priv::avr109_dev_name(Avr109Pid usb_pid) {
 			return "Prusa MMU 2.0 Control";
 		break;
 		case USB_PID_CW1_BOOT:
-			return "Prusa CurWa";
+			return "Original Prusa CW1";
 		break;
 
 		default: throw std::runtime_error((boost::format("Invalid avr109 device USB PID: %1%") % usb_pid.boot).str());

src/slic3r/GUI/GUI_Utils.cpp

@@ -12,6 +12,8 @@
 #include <wx/sizer.h>
 #include <wx/checkbox.h>
 #include <wx/dcclient.h>
+#include <wx/font.h>
+#include <wx/fontutil.h>
 
 #include "libslic3r/Config.hpp"
 
@@ -113,6 +115,32 @@ int get_dpi_for_window(wxWindow *window)
 #endif
 }
 
+wxFont get_default_font_for_dpi(int dpi)
+{
+#ifdef _WIN32
+    // First try to load the font with the Windows 10 specific way.
+    struct SystemParametersInfoForDpi_t { typedef BOOL (WINAPI *FN)(UINT uiAction, UINT uiParam, PVOID pvParam, UINT fWinIni, UINT dpi); };
+    static auto SystemParametersInfoForDpi_fn = winapi_get_function<SystemParametersInfoForDpi_t>(L"User32.dll", "SystemParametersInfoForDpi");
+    if (SystemParametersInfoForDpi_fn != nullptr) {
+        NONCLIENTMETRICS nm;
+        memset(&nm, 0, sizeof(NONCLIENTMETRICS));
+        nm.cbSize = sizeof(NONCLIENTMETRICS);
+        if (SystemParametersInfoForDpi_fn(SPI_GETNONCLIENTMETRICS, 0, &nm, 0, dpi)) {
+            wxNativeFontInfo info;
+            info.lf = nm.lfMessageFont;
+            return wxFont(info);
+        }
+    }
+    // Then try to guesstimate the font DPI scaling on Windows 8.
+    // Let's hope that the font returned by the SystemParametersInfo(), which is used by wxWidgets internally, makes sense.
+    int dpi_primary = get_dpi_for_window(nullptr);
+    if (dpi_primary != dpi) {
+        // Rescale the font.
+        return wxSystemSettings::GetFont(wxSYS_DEFAULT_GUI_FONT).Scaled(float(dpi) / float(dpi_primary));
+    }
+#endif
+    return wxSystemSettings::GetFont(wxSYS_DEFAULT_GUI_FONT);
+}
 
 CheckboxFileDialog::ExtraPanel::ExtraPanel(wxWindow *parent)
     : wxPanel(parent, wxID_ANY)

src/slic3r/GUI/GUI_Utils.hpp

@@ -34,6 +34,7 @@ void on_window_geometry(wxTopLevelWindow *tlw, std::function<void()> callback);
 enum { DPI_DEFAULT = 96 };
 
 int get_dpi_for_window(wxWindow *window);
+wxFont get_default_font_for_dpi(int dpi);
 
 struct DpiChangedEvent : public wxEvent {
     int dpi;
@@ -58,12 +59,10 @@ public:
         const wxSize &size=wxDefaultSize, long style=wxDEFAULT_FRAME_STYLE, const wxString &name=wxFrameNameStr)
         : P(parent, id, title, pos, size, style, name)
     {
-        m_scale_factor = (float)get_dpi_for_window(this) / (float)DPI_DEFAULT;
+        int dpi = get_dpi_for_window(this);
+        m_scale_factor = (float)dpi / (float)DPI_DEFAULT;
         m_prev_scale_factor = m_scale_factor;
-		float scale_primary_display = (float)get_dpi_for_window(nullptr) / (float)DPI_DEFAULT;
+		m_normal_font = get_default_font_for_dpi(dpi);
-		m_normal_font = wxSystemSettings::GetFont(wxSYS_DEFAULT_GUI_FONT);
-		if (std::abs(m_scale_factor - scale_primary_display) > 1e-6)
-			m_normal_font = m_normal_font.Scale(m_scale_factor / scale_primary_display);
 
         // initialize default width_unit according to the width of the one symbol ("m") of the currently active font of this window.
         m_em_unit = std::max<size_t>(10, this->GetTextExtent("m").x - 1);