Windows support

client/Common.cpp

@@ -2,10 +2,21 @@
 
 #include <algorithm>
 #include <cmath>
+#include <filesystem>
 #include <vector>
 
 namespace bs {
 
+const std::string& engineAssetDir() {
+    static const std::string dir = [] {
+        std::filesystem::path packaged = executableDir() / "engine";
+        std::error_code ec;
+        if (std::filesystem::exists(packaged / "shaders" / "common.glsl", ec)) return packaged.string();
+        return std::string(HD2D_ENGINE_ASSET_DIR);
+    }();
+    return dir;
+}
+
 void UiTexture::upload(const hd2d::Image& img) {
     if (id_ && size_ != glm::ivec2(img.width, img.height)) reset();
     if (!id_) {