fix: editor should load fonts via Physfs

src/gui/GuiManager.cpp

@@ -10,6 +10,7 @@
 #include <cmath>
 #include <cstdio>
 #include <sstream>
+#include <climits>
 #include <entt.hpp>
 #include "log.h"
 #include "Application.h"
@@ -17,9 +18,56 @@
 #include "SceneGraph.h"
 #include "SceneLoader.h"
 #include "PhysFSManager.h"
+#include "physfs.h"
 #define IMVIEWGUIZMO_IMPLEMENTATION
 #include "ImViewGuizmoRaymath.h"
 
+static ImFont* AddFontFromPhysFS(ImFontAtlas* atlas, const char* path, float size,
+                                 ImFontConfig* config = nullptr, const ImWchar* ranges = nullptr)
+{
+    if (!atlas || !path) {
+        return nullptr;
+    }
+
+    PHYSFS_File* file = PhysFSManager::OpenRead(path);
+    if (!file) {
+        log_warn("ImGui font missing: %s", path);
+        return nullptr;
+    }
+
+    PHYSFS_sint64 length = PHYSFS_fileLength(file);
+    if (length <= 0 || length > static_cast<PHYSFS_sint64>(INT32_MAX)) {
+        PhysFSManager::Close(file);
+        log_warn("ImGui font invalid size: %s", path);
+        return nullptr;
+    }
+
+    unsigned char* data = static_cast<unsigned char*>(IM_ALLOC(static_cast<size_t>(length)));
+    if (!data) {
+        PhysFSManager::Close(file);
+        log_warn("ImGui font alloc failed: %s", path);
+        return nullptr;
+    }
+
+    PHYSFS_sint64 read = PHYSFS_readBytes(file, data, length);
+    PhysFSManager::Close(file);
+    if (read != length) {
+        IM_FREE(data);
+        log_warn("ImGui font read failed: %s", path);
+        return nullptr;
+    }
+
+    ImFontConfig localConfig;
+    if (!config) {
+        localConfig.FontDataOwnedByAtlas = true;
+        config = &localConfig;
+    } else {
+        config->FontDataOwnedByAtlas = true;
+    }
+
+    return atlas->AddFontFromMemoryTTF(data, static_cast<int>(length), size, config, ranges);
+}
+
 GuiManager::GuiManager() {}
 
 GuiManager::~GuiManager() {}
@@ -2126,7 +2174,10 @@ void GuiManager::SetTheme()
     io.Fonts->Clear();
 
     // Don't clear; just add new fonts and rebuild
-    io.Fonts->AddFontFromFileTTF("fonts/Inter-Regular.ttf", 16); // index 0 (replaces default)
+    ImFont* baseFont = AddFontFromPhysFS(io.Fonts, "fonts/Inter-Regular.ttf", 16);
+    if (!baseFont) {
+        baseFont = io.Fonts->AddFontDefault();
+    }
 
     // Re-add FontAwesome as merge into default (index 0)
     float iconFontSize = 16.0f * 2.0f / 3.0f;
@@ -2138,7 +2189,7 @@ void GuiManager::SetTheme()
     io.Fonts->AddFontFromMemoryCompressedTTF(fa_solid_900_compressed_data,
                                              fa_solid_900_compressed_size,
                                              iconFontSize, &iconsConfig, iconsRanges);
-    io.Fonts->AddFontFromFileTTF("fonts/JetBrainsMono-Regular.ttf", 16);
+    AddFontFromPhysFS(io.Fonts, "fonts/JetBrainsMono-Regular.ttf", 16);
     io.Fonts->Build();
 
     ImVec4 *colors = ImGui::GetStyle().Colors;