add resize implementation on Linux and texture/render target destruction etc

ios/src/FilamentViewer.cpp

@@ -573,6 +573,15 @@ void FilamentViewer::createRenderTarget(uint32_t glTextureId, uint32_t width, ui
 }
 
 void FilamentViewer::destroySwapChain() {
+  if(_rt) {
+    _view->setRenderTarget(nullptr);
+    _engine->destroy(_rtDepth);
+    _engine->destroy(_rtColor);
+    _engine->destroy(_rt);
+    _rt = nullptr;
+    _rtDepth = nullptr;
+    _rtColor = nullptr;
+  }
   if (_swapChain) {
     _engine->destroy(_swapChain);
     _swapChain = nullptr;

linux/filament_texture.cc

@@ -32,7 +32,9 @@ filament_texture_populate (FlTextureGL *texture,
 }
 
 void filament_texture_gl_dispose(GObject* object) {
-    G_OBJECT_CLASS(filament_texture_gl_parent_class)->dispose(object);
+  auto filamentTextureGL = FILAMENT_TEXTURE_GL(object);
+  glDeleteTextures(1, &(filamentTextureGL->texture_id));
+  filamentTextureGL->texture_id = 0;
 }
 
 void filament_texture_gl_class_init(FilamentTextureGLClass* klass) {
@@ -42,10 +44,15 @@ void filament_texture_gl_class_init(FilamentTextureGLClass* klass) {
 
 void filament_texture_gl_init(FilamentTextureGL* self) { }
 
-FLUTTER_PLUGIN_EXPORT FlTexture* create_filament_texture(uint32_t width, uint32_t height, FlTextureRegistrar* registrar) {   
+void destroy_filament_texture(FlTexture* texture, FlTextureRegistrar* registrar) { 
+  fl_texture_registrar_unregister_texture(registrar, texture);
+}
+
+FlTexture* create_filament_texture(uint32_t width, uint32_t height, FlTextureRegistrar* registrar) {   
   auto textureGL = FILAMENT_TEXTURE_GL(g_object_new(filament_texture_gl_get_type(), nullptr));
   textureGL->width = width;
   textureGL->height = height;
+  textureGL->registrar = registrar;
 
   g_autoptr(FlTexture) texture = FL_TEXTURE(textureGL);
 
@@ -61,13 +68,13 @@ FLUTTER_PLUGIN_EXPORT FlTexture* create_filament_texture(uint32_t width, uint32_
   glTexImage2D (GL_TEXTURE_2D, 0, GL_RGBA8, textureGL->width, textureGL->height, 0, GL_RGBA,
                   GL_UNSIGNED_BYTE, 0);
    
-    if(fl_texture_registrar_register_texture(registrar, texture) == TRUE) { 
+  if(fl_texture_registrar_register_texture(registrar, texture) == TRUE) { 
 
-      if(fl_texture_registrar_mark_texture_frame_available(registrar,
-                                                      texture) != TRUE) {
-        std::cout << "FAILED" << std::endl;
-        return nullptr;
-      } 
-    }
-    return texture;
+    if(fl_texture_registrar_mark_texture_frame_available(registrar,
+                                                    texture) != TRUE) {
+      std::cout << "FAILED" << std::endl;
+      return nullptr;
+    } 
+  }
+  return texture;
 }

linux/include/polyvox_filament/filament_texture.h

@@ -26,6 +26,7 @@ struct _FilamentTextureGL {
     GLuint texture_id;
     uint32_t width;
     uint32_t height;
+    FlTextureRegistrar* registrar;
 };
 
 typedef struct _FilamentTextureGL FilamentTextureGL;
@@ -37,12 +38,12 @@ typedef struct {
                        uint32_t* width,
                        uint32_t* height,
                        GError** error);
-
   GLuint texture_id;
 } FilamentTextureGLClass;
 
 G_END_DECLS
 
 FLUTTER_PLUGIN_EXPORT FlTexture* create_filament_texture(uint32_t width, uint32_t height, FlTextureRegistrar* registrar);
+FLUTTER_PLUGIN_EXPORT void destroy_filament_texture(FlTexture* texture, FlTextureRegistrar* registrar);
 
 #endif 

linux/polyvox_filament_plugin.cc

@@ -38,9 +38,11 @@ struct _PolyvoxFilamentPlugin {
   GObject parent_instance;
   FlTextureRegistrar* texture_registrar;
   FlView* fl_view;
-
   FlTexture* texture;
   void* _viewer;
+
+  double width;
+  double height;
 };
 
 G_DEFINE_TYPE(PolyvoxFilamentPlugin, polyvox_filament_plugin, g_object_get_type())
@@ -72,7 +74,9 @@ static FlMethodResponse* _initialize(PolyvoxFilamentPlugin* self, FlMethodCall*
     const double width = fl_value_get_float(fl_value_get_list_value(args, 0));
     const double height = fl_value_get_float(fl_value_get_list_value(args, 1));
 
-   
+    self->width = width;
+    self->height = height;
+
     auto texture = create_filament_texture(uint32_t(width), uint32_t(height), self->texture_registrar);
     //auto texture = create_filament_pb_texture(uint32_t(width), uint32_t(height), self->texture_registrar);
     self->texture = texture;
@@ -364,6 +368,37 @@ static FlMethodResponse* _get_target_names(PolyvoxFilamentPlugin* self, FlMethod
   return FL_METHOD_RESPONSE(fl_method_success_response_new(result));    
 }
 
+// TODO - defer the destruction of the old texture until this call has returned
+// otherwise the front-end may render using the destroyed texture ID for a single frame (hopefully no more)
+static FlMethodResponse* _resize(PolyvoxFilamentPlugin* self, FlMethodCall* method_call) { 
+  FlValue* args = fl_method_call_get_args(method_call);
+  
+  const double width = fl_value_get_float(fl_value_get_list_value(args, 0));
+  const double height = fl_value_get_float(fl_value_get_list_value(args, 1));
+
+  if(width != self->width || height != self->height) {
+
+    destroy_swap_chain(self->_viewer);
+
+    destroy_filament_texture(self->texture, self->texture_registrar);
+
+    self->texture = create_filament_texture(uint32_t(width), uint32_t(height), self->texture_registrar);
+
+    create_swap_chain(self->_viewer, nullptr, width, height);
+    create_render_target(self->_viewer, ((FilamentTextureGL*)self->texture)->texture_id,width,height);
+      
+    update_viewport_and_camera_projection(self->_viewer, width, height, 1.0f);
+
+    std::cout << "Created new texture " << self->texture << std::endl;
+  }
+
+  g_autoptr(FlValue) result =   
+         fl_value_new_int(reinterpret_cast<int64_t>(self->texture));   
+      
+  return FL_METHOD_RESPONSE(fl_method_success_response_new(result));    
+}
+
+
 // Called when a method call is received from Flutter.
 static void polyvox_filament_plugin_handle_method_call(
     PolyvoxFilamentPlugin* self,
@@ -380,13 +415,7 @@ static void polyvox_filament_plugin_handle_method_call(
   } else if(strcmp(method, "removeSkybox") == 0) {
     response = _removeSkybox(self, method_call);    
   } else if(strcmp(method, "resize") == 0) { 
-      // val args = call.arguments as ArrayList<Int>
-      // val width = args[0]
-      // val height = args[1]
-      // val scale = if(args.size > 2) (args[2] as Double).toFloat() else 1.0f
-      // surfaceTexture!!.setDefaultBufferSize(width, height)
-      // _lib.update_viewport_and_camera_projection(_viewer!!, width, height, scale);
-      // result.success(null)
+    response = _resize(self, method_call);    
   } else if(strcmp(method, "render") == 0) {
     render(self->_viewer, 0);
     g_autoptr(FlValue) result = fl_value_new_string("OK");