replace view with texture, move plugin to Swift implementation

ios/Classes/PolyvoxFilamentIOSApi.cc

@@ -0,0 +1,32 @@
+#include "PolyvoxFilamentApi.h"
+#include "FilamentViewer.hpp"
+#include "ResourceBuffer.hpp"
+#include "SceneResources.hpp"
+#include <functional>
+
+using namespace polyvox;
+using namespace std;
+
+extern "C" {
+    using RawLoadType = ResourceBuffer(const char*, void* resource);
+    using RawFreeType = void(uint32_t, void*);
+
+    void* filament_viewer_new_ios(void* pb, void* loadResource, void* freeResource, void* resources) {
+            
+      FreeResource _freeResource = [=](uint32_t rid) {
+        reinterpret_cast<RawFreeType*>(freeResource)(rid, resources);
+      };
+    
+      function<ResourceBuffer(const char*)> _loadResource = [=](const char* uri){
+        auto cast = reinterpret_cast<RawLoadType*>(loadResource);
+        return cast(uri, resources);
+      };
+            
+      auto viewer = new FilamentViewer(pb,_loadResource, _freeResource);
+
+      return (void*)viewer;
+    }
+    void create_swap_chain(void* viewer, void* texture) {
+        ((FilamentViewer*)viewer)->createSwapChain(texture);
+    }
+}