Correct font scaling with resolution

src/app/app.cpp

@@ -903,14 +903,14 @@ Event CApplication::ProcessSystemEvent()
     {
         event.type = EVENT_QUIT;
     }
-    /*else if (m_private->currentEvent.type == SDL_VIDEORESIZE)
+    else if (m_private->currentEvent.type == SDL_VIDEORESIZE)
     {
         Gfx::GLDeviceConfig newConfig = m_deviceConfig;
         newConfig.size.x = m_private->currentEvent.resize.w;
         newConfig.size.y = m_private->currentEvent.resize.h;
         if (newConfig.size != m_deviceConfig.size)
             ChangeVideoConfig(newConfig);
-    }*/
+    }
     else if ( (m_private->currentEvent.type == SDL_KEYDOWN) ||
               (m_private->currentEvent.type == SDL_KEYUP) )
     {

src/graphics/engine/engine.cpp

@@ -281,6 +281,8 @@ void CEngine::Destroy()
 
 void CEngine::ResetAfterDeviceChanged()
 {
+    m_size = m_app->GetVideoConfig().size;;
+
     m_text->FlushCache();
 
     // TODO reload textures, reset device state, etc.

src/graphics/engine/text.cpp

@@ -46,7 +46,7 @@ struct CachedFont
 };
 
 
-
+const Math::IntPoint REFERENCE_SIZE(800, 600);
 
 
 CText::CText(CInstanceManager *iMan, CEngine* engine)
@@ -147,6 +147,10 @@ void CText::FlushCache()
             f->cache.clear();
         }
     }
+
+    m_lastFontType = FONT_COLOBOT;
+    m_lastFontSize = 0;
+    m_lastCachedFont = nullptr;
 }
 
 void CText::DrawText(const std::string &text, std::map<unsigned int, FontMetaChar> &format,
@@ -723,8 +727,8 @@ void CText::DrawCharAndAdjustPos(UTF8Char ch, FontType font, float size, Math::P
 
 CachedFont* CText::GetOrOpenFont(FontType font, float size)
 {
-    // TODO: sizing
-    int pointSize = static_cast<int>(size);
+    Math::IntPoint windowSize = m_engine->GetWindowSize();
+    int pointSize = static_cast<int>(size * (windowSize.Length() / REFERENCE_SIZE.Length()));
 
     if (m_lastCachedFont != nullptr)
     {

src/math/intpoint.h

@@ -21,6 +21,7 @@
 
 #pragma once
 
+#include <cmath>
 
 // Math module namespace
 namespace Math {
@@ -49,6 +50,11 @@ struct IntPoint
     {
         return !operator==(p);
     }
+
+    inline float Length() const
+    {
+        return sqrtf(x*x + y*y);
+    }
 };