From 02b5df03ab276e0e0f92d06f6b8a3410f0599e5f Mon Sep 17 00:00:00 2001
From: WerWolv <werwolv98@gmail.com>
Date: Mon, 10 Feb 2025 12:02:05 +0100
Subject: [PATCH] impr: Drastically reduce font-related memory usage

---
 main/gui/source/window/window.cpp      | 10 +++++++--
 plugins/fonts/include/font_atlas.hpp   | 30 ++++++++++++++++++++++++++
 plugins/fonts/source/font_loader.cpp   |  1 +
 plugins/fonts/source/library_fonts.cpp |  4 ++--
 4 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/main/gui/source/window/window.cpp b/main/gui/source/window/window.cpp
index 3003302c5..1d712b17a 100644
--- a/main/gui/source/window/window.cpp
+++ b/main/gui/source/window/window.cpp
@@ -334,6 +334,9 @@ namespace hex {
     }
 
     void Window::frameBegin() {
+        ImGui_ImplOpenGL3_NewFrame();
+        ImGui_ImplGlfw_NewFrame();
+
         // Create font textures if necessary
         {
             const auto &fontDefinitions = ImHexApi::Fonts::impl::getFontDefinitions();
@@ -345,6 +348,8 @@ namespace hex {
 
                 currentFont = font->ContainerAtlas;
                 ImGui_ImplOpenGL3_CreateFontsTexture();
+                currentFont->ClearInputData();
+                currentFont->ClearTexData();
             }
 
             {
@@ -359,6 +364,8 @@ namespace hex {
                     cfg.SizePixels = ImHexApi::Fonts::DefaultFontSize;
                     io.Fonts->AddFontDefault(&cfg);
                     ImGui_ImplOpenGL3_CreateFontsTexture();
+                    io.Fonts->ClearInputData();
+                    io.Fonts->ClearTexData();
                 } else {
                     currentFont = font->ContainerAtlas;
                 }
@@ -366,8 +373,7 @@ namespace hex {
         }
 
         // Start new ImGui Frame
-        ImGui_ImplOpenGL3_NewFrame();
-        ImGui_ImplGlfw_NewFrame();
+
         ImGui::NewFrame();
 
         TutorialManager::drawTutorial();
diff --git a/plugins/fonts/include/font_atlas.hpp b/plugins/fonts/include/font_atlas.hpp
index a0811cf85..72512aaac 100644
--- a/plugins/fonts/include/font_atlas.hpp
+++ b/plugins/fonts/include/font_atlas.hpp
@@ -53,6 +53,36 @@ namespace hex::fonts {
         FontAtlas(const FontAtlas &) = delete;
         FontAtlas &operator=(const FontAtlas &) = delete;
 
+        FontAtlas(FontAtlas &&other) noexcept {
+            m_fontAtlas = other.m_fontAtlas;
+            other.m_fontAtlas = nullptr;
+
+            m_defaultConfig = other.m_defaultConfig;
+            m_fontSizes = std::move(other.m_fontSizes);
+            m_fontConfigs = std::move(other.m_fontConfigs);
+            m_glyphRange = std::move(other.m_glyphRange);
+            m_fontData = std::move(other.m_fontData); 
+        }
+
+        FontAtlas& operator=(FontAtlas &&other) noexcept {
+            if (this != &other) {
+                if (m_fontAtlas != nullptr) {
+                    IM_DELETE(m_fontAtlas);
+                }
+
+                m_fontAtlas = other.m_fontAtlas;
+                other.m_fontAtlas = nullptr;
+
+                m_defaultConfig = other.m_defaultConfig;
+                m_fontSizes = std::move(other.m_fontSizes);
+                m_fontConfigs = std::move(other.m_fontConfigs);
+                m_glyphRange = std::move(other.m_glyphRange);
+                m_fontData = std::move(other.m_fontData);
+            }
+
+            return *this;
+        }
+
         ~FontAtlas() {
             if (m_fontAtlas != nullptr) {
                 m_fontAtlas->Locked = false;
diff --git a/plugins/fonts/source/font_loader.cpp b/plugins/fonts/source/font_loader.cpp
index 3bd777cc6..eb488c31d 100644
--- a/plugins/fonts/source/font_loader.cpp
+++ b/plugins/fonts/source/font_loader.cpp
@@ -97,6 +97,7 @@ namespace hex::fonts {
 
         // Build the font atlas
         if (fontAtlas->build()) {
+            fontAtlas->reset();
             return true;
         }
 
diff --git a/plugins/fonts/source/library_fonts.cpp b/plugins/fonts/source/library_fonts.cpp
index 07dde9139..ab693c73b 100644
--- a/plugins/fonts/source/library_fonts.cpp
+++ b/plugins/fonts/source/library_fonts.cpp
@@ -16,7 +16,7 @@ namespace hex::fonts {
 
     bool buildFontAtlas(FontAtlas *fontAtlas, std::fs::path fontPath, bool pixelPerfectFont, float fontSize, bool loadUnicodeCharacters, bool bold, bool italic, bool antialias);
 
-    static AutoReset<std::map<ImFont*, std::unique_ptr<FontAtlas>>> s_fontAtlases;
+    static AutoReset<std::map<UnlocalizedString, std::unique_ptr<FontAtlas>>> s_fontAtlases;
 
     void loadFont(const ContentRegistry::Settings::Widgets::Widget &widget, const UnlocalizedString &name, ImFont **font, float scale) {
         const auto &settings = static_cast<const FontSelector&>(widget);
@@ -51,7 +51,7 @@ namespace hex::fonts {
 
         *font = atlas->getAtlas()->Fonts[0];
 
-        (*s_fontAtlases)[*font] = std::move(atlas);
+        (*s_fontAtlases)[name] = std::move(atlas);
     }
 
     bool setupFonts() {