Fixed possible corrupted text when changing the font scale with the S…

…FML backend

changelog.md

@@ -2,6 +2,7 @@ TGUI 1.7  (TBD)
 ---------------
 
 - New widgets: GrowHorizontalLayout and GrowVerticalLayout
+- Fixed some issues with font scale in SFML font backend
 
 
 TGUI 1.6.1  (8 October 2024)

include/TGUI/Backend/Font/SFML-Graphics/BackendFontSFML.hpp

@@ -218,6 +218,10 @@ TGUI_MODULE_EXPORT namespace tgui
         // from breaking since sf::Font does the same.
         std::map<unsigned int, std::shared_ptr<BackendTexture>> m_textures;
         std::map<unsigned int, unsigned int> m_textureVersions;
+
+        // We use a single version that is unique across all text sizes. Otherwise switching from size by changing the font scale
+        // can result in the same version being accidentally returned and the text not realizing that the texture changed.
+        unsigned int m_lastTextureVersion = 0;
     };
 }
 

src/Backend/Font/SFML-Graphics/BackendFontSFML.cpp

@@ -243,7 +243,8 @@ namespace tgui
         }
         m_textures[scaledTextSize] = texture;
 
-        textureVersion = ++m_textureVersions[scaledTextSize];
+        textureVersion = ++m_lastTextureVersion;
+        m_textureVersions[scaledTextSize] = textureVersion;
         return texture;
     }
 

tests/Widget.cpp

@@ -639,6 +639,28 @@ TEST_CASE("[Widget]")
 
             TEST_DRAW("OriginScaleRotation.png")
         }
+
+        SECTION("Font scale")
+        {
+            auto button = tgui::Button::create();
+            button->setSize(150, 50);
+            button->setText("Scaling");
+            button->setTextSize(32);
+            button->setPosition(5, 10);
+
+            TEST_DRAW_INIT(400, 175, button)
+
+            auto oldView = gui.getView();
+            gui.setAbsoluteView({0, 0, 160, 70});
+
+            TEST_DRAW("FontScale_Unscaled.png")
+
+            tgui::getBackend()->setFontScale(2.5f);
+            TEST_DRAW("FontScale_Scaled.png")
+
+            tgui::getBackend()->setFontScale(1);
+            gui.setAbsoluteView(oldView.getRect());
+        }
     }
 
     SECTION("Bug Fixes")