ARKit for Godot 3.2

This PR introduces support for ARKit to the iOS version of Godot.
ARKit is Apples Augmented Reality platform.
This PR brings in support for ARKit 1.0 and implements a few ARKit 2.0 features.
It requires iOS 11 to run but should not prevent Godot from running on older versions as long as ARKit remains unused.

8 files changed, 1061 insertions, 0 deletions

diff --git a/modules/arkit/SCsub b/modules/arkit/SCsub
new file mode 100644
index 0000000000..b43d936768
--- /dev/null
+++ b/modules/arkit/SCsub
@@ -0,0 +1,10 @@
+#!/usr/bin/env python
+
+Import('env')
+Import('env_modules')
+
+env_arkit = env_modules.Clone()
+
+# Add source files
+env_arkit.add_source_files(env.modules_sources, "*.cpp")
+env_arkit.add_source_files(env.modules_sources, "*.mm")
diff --git a/modules/arkit/arkit_interface.h b/modules/arkit/arkit_interface.h
new file mode 100644
index 0000000000..8129611287
--- /dev/null
+++ b/modules/arkit/arkit_interface.h
@@ -0,0 +1,125 @@
+/*************************************************************************/
+/*  arkit_interface.h                                                    */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                    http://www.godotengine.org                         */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef ARKIT_INTERFACE_H
+#define ARKIT_INTERFACE_H
+
+#include "servers/arvr/arvr_interface.h"
+#include "servers/arvr/arvr_positional_tracker.h"
+#include "servers/camera/camera_feed.h"
+
+/**
+	@author Bastiaan Olij <mux213@gmail.com>
+
+	ARKit interface between iPhone and Godot
+*/
+
+// forward declaration for some needed objects
+class ARKitShader;
+
+class ARKitInterface : public ARVRInterface {
+	GDCLASS(ARKitInterface, ARVRInterface);
+
+private:
+	bool initialized;
+	bool session_was_started;
+	bool plane_detection_is_enabled;
+	bool light_estimation_is_enabled;
+	real_t ambient_intensity;
+	real_t ambient_color_temperature;
+
+	Transform transform;
+	CameraMatrix projection;
+	float eye_height, z_near, z_far;
+
+	Ref<CameraFeed> feed;
+	int image_width[2];
+	int image_height[2];
+	PoolVector<uint8_t> img_data[2];
+
+	struct anchor_map {
+		ARVRPositionalTracker *tracker;
+		unsigned char uuid[16];
+	};
+
+	///@TODO should use memory map object from Godot?
+	unsigned int num_anchors;
+	unsigned int max_anchors;
+	anchor_map *anchors;
+	ARVRPositionalTracker *get_anchor_for_uuid(const unsigned char *p_uuid);
+	void remove_anchor_for_uuid(const unsigned char *p_uuid);
+	void remove_all_anchors();
+
+protected:
+	static void _bind_methods();
+
+public:
+	void start_session();
+	void stop_session();
+
+	bool get_anchor_detection_is_enabled() const;
+	void set_anchor_detection_is_enabled(bool p_enable);
+	virtual int get_camera_feed_id();
+
+	bool get_light_estimation_is_enabled() const;
+	void set_light_estimation_is_enabled(bool p_enable);
+
+	real_t get_ambient_intensity() const;
+	real_t get_ambient_color_temperature() const;
+
+	/* while Godot has its own raycast logic this takes ARKits camera into account and hits on any ARAnchor */
+	Array raycast(Vector2 p_screen_coord);
+
+	void notification(int p_what);
+
+	virtual StringName get_name() const;
+	virtual int get_capabilities() const;
+
+	virtual bool is_initialized() const;
+	virtual bool initialize();
+	virtual void uninitialize();
+
+	virtual Size2 get_render_targetsize();
+	virtual bool is_stereo();
+	virtual Transform get_transform_for_eye(ARVRInterface::Eyes p_eye, const Transform &p_cam_transform);
+	virtual CameraMatrix get_projection_for_eye(ARVRInterface::Eyes p_eye, real_t p_aspect, real_t p_z_near, real_t p_z_far);
+	virtual void commit_for_eye(ARVRInterface::Eyes p_eye, RID p_render_target, const Rect2 &p_screen_rect);
+
+	virtual void process();
+
+	// called by delegate (void * because C++ and Obj-C don't always mix, should really change all platform/iphone/*.cpp files to .mm)
+	void _add_or_update_anchor(void *p_anchor);
+	void _remove_anchor(void *p_anchor);
+
+	ARKitInterface();
+	~ARKitInterface();
+};
+
+#endif /* !ARKIT_INTERFACE_H */
diff --git a/modules/arkit/arkit_interface.mm b/modules/arkit/arkit_interface.mm
new file mode 100644
index 0000000000..de58f93276
--- /dev/null
+++ b/modules/arkit/arkit_interface.mm
@@ -0,0 +1,738 @@
+/*************************************************************************/
+/*  arkit_interface.mm                                                   */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                    http://www.godotengine.org                         */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "camera_ios.h"
+#include "core/os/input.h"
+#include "core/os/os.h"
+#include "scene/resources/surface_tool.h"
+#include "servers/visual/visual_server_globals.h"
+
+#import <ARKit/ARKit.h>
+#import <UIKit/UIKit.h>
+
+#include "arkit_interface.h"
+#include "arkit_session_delegate.h"
+
+// just a dirty workaround for now, declare these as globals. I'll probably encapsulate ARSession and associated logic into an mm object and change ARKitInterface to a normal cpp object that consumes it.
+ARSession *ar_session;
+ARKitSessionDelegate *ar_delegate;
+NSTimeInterval last_timestamp;
+
+/* this is called when we initialize or when we come back from having our app pushed to the background, just (re)start our session */
+void ARKitInterface::start_session() {
+	// We're active...
+	session_was_started = true;
+
+	// Ignore this if we're not initialized...
+	if (initialized) {
+		print_line("Starting ARKit session");
+		ARWorldTrackingConfiguration *configuration = [ARWorldTrackingConfiguration new];
+		configuration.lightEstimationEnabled = light_estimation_is_enabled;
+		if (plane_detection_is_enabled) {
+			configuration.planeDetection = ARPlaneDetectionVertical | ARPlaneDetectionHorizontal;
+		} else {
+			configuration.planeDetection = 0;
+		}
+
+		// make sure our camera is on
+		if (feed.is_valid()) {
+			feed->set_active(true);
+		}
+
+		[ar_session runWithConfiguration:configuration];
+	}
+}
+
+void ARKitInterface::stop_session() {
+	session_was_started = false;
+
+	// Ignore this if we're not initialized...
+	if (initialized) {
+		// make sure our camera is off
+		if (feed.is_valid()) {
+			feed->set_active(false);
+		}
+
+		[ar_session pause];
+	}
+}
+
+void ARKitInterface::notification(int p_what) {
+	// TODO, this is not being called, need to find out why, possibly because this is not a node.
+	// in that case we need to find a way to get these notifications!
+	switch (p_what) {
+		case MainLoop::NOTIFICATION_WM_FOCUS_IN: {
+			print_line("Focus in");
+
+			start_session();
+		}; break;
+		case MainLoop::NOTIFICATION_WM_FOCUS_OUT: {
+			print_line("Focus out");
+
+			stop_session();
+		}; break;
+		default:
+			break;
+	}
+}
+
+bool ARKitInterface::get_anchor_detection_is_enabled() const {
+	return plane_detection_is_enabled;
+}
+
+void ARKitInterface::set_anchor_detection_is_enabled(bool p_enable) {
+	if (plane_detection_is_enabled != p_enable) {
+		plane_detection_is_enabled = p_enable;
+
+		// Restart our session (this will be ignore if we're not initialised)
+		if (session_was_started) {
+			start_session();
+		}
+	}
+}
+
+int ARKitInterface::get_camera_feed_id() {
+	if (feed.is_null()) {
+		return 0;
+	} else {
+		return feed->get_id();
+	}
+}
+
+bool ARKitInterface::get_light_estimation_is_enabled() const {
+	return light_estimation_is_enabled;
+}
+
+void ARKitInterface::set_light_estimation_is_enabled(bool p_enable) {
+	if (light_estimation_is_enabled != p_enable) {
+		light_estimation_is_enabled = p_enable;
+
+		// Restart our session (this will be ignore if we're not initialised)
+		if (session_was_started) {
+			start_session();
+		}
+	}
+}
+
+real_t ARKitInterface::get_ambient_intensity() const {
+	return ambient_intensity;
+}
+
+real_t ARKitInterface::get_ambient_color_temperature() const {
+	return ambient_color_temperature;
+}
+
+StringName ARKitInterface::get_name() const {
+	return "ARKit";
+}
+
+int ARKitInterface::get_capabilities() const {
+	return ARKitInterface::ARVR_MONO + ARKitInterface::ARVR_AR;
+}
+
+Array ARKitInterface::raycast(Vector2 p_screen_coord) {
+	Array arr;
+	Size2 screen_size = OS::get_singleton()->get_window_size();
+	CGPoint point;
+	point.x = p_screen_coord.x / screen_size.x;
+	point.y = p_screen_coord.y / screen_size.y;
+
+	///@TODO maybe give more options here, for now we're taking just ARAchors into account that were found during plane detection keeping their size into account
+	NSArray<ARHitTestResult *> *results = [ar_session.currentFrame hittest:point types:ARHitTestResultTypeExistingPlaneUsingExtent];
+
+	for (ARHitTestResult *result in results) {
+		Transform transform;
+
+		matrix_float4x4 m44 = result.worldTransform;
+		transform.basis.elements[0].x = m44.columns[0][0];
+		transform.basis.elements[1].x = m44.columns[0][1];
+		transform.basis.elements[2].x = m44.columns[0][2];
+		transform.basis.elements[0].y = m44.columns[1][0];
+		transform.basis.elements[1].y = m44.columns[1][1];
+		transform.basis.elements[2].y = m44.columns[1][2];
+		transform.basis.elements[0].z = m44.columns[2][0];
+		transform.basis.elements[1].z = m44.columns[2][1];
+		transform.basis.elements[2].z = m44.columns[2][2];
+		transform.origin.x = m44.columns[3][0];
+		transform.origin.y = m44.columns[3][1];
+		transform.origin.z = m44.columns[3][2];
+
+		/* important, NOT scaled to world_scale !! */
+		arr.push_back(transform);
+	}
+
+	return arr;
+}
+
+void ARKitInterface::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("_notification", "what"), &ARKitInterface::_notification);
+
+	ClassDB::bind_method(D_METHOD("set_light_estimation_is_enabled", "enable"), &ARKitInterface::set_light_estimation_is_enabled);
+	ClassDB::bind_method(D_METHOD("get_light_estimation_is_enabled"), &ARKitInterface::get_light_estimation_is_enabled);
+	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "light_estimation"), "set_light_estimation_is_enabled", "get_light_estimation_is_enabled");
+
+	ClassDB::bind_method(D_METHOD("get_ambient_intensity"), &ARKitInterface::get_ambient_intensity);
+	ClassDB::bind_method(D_METHOD("get_ambient_color_temperature"), &ARKitInterface::get_ambient_color_temperature);
+
+	ClassDB::bind_method(D_METHOD("raycast", "screen_coord"), &ARKitInterface::raycast);
+}
+
+bool ARKitInterface::is_stereo() {
+	// this is a mono device...
+	return false;
+}
+
+bool ARKitInterface::is_initialized() const {
+	return initialized;
+}
+
+bool ARKitInterface::initialize() {
+	ARVRServer *arvr_server = ARVRServer::get_singleton();
+	ERR_FAIL_NULL_V(arvr_server, false);
+
+	if (!initialized) {
+		print_line("initializing ARKit");
+
+		// create our ar session and delegate
+		ar_session = [ARSession new];
+		ar_delegate = [ARKitSessionDelegate new];
+		ar_delegate.arkit_interface = this;
+		ar_session.delegate = ar_delegate;
+
+		// reset our transform
+		transform = Transform();
+
+		// make this our primary interface
+		arvr_server->set_primary_interface(this);
+
+		// make sure we have our feed setup
+		if (feed.is_null()) {
+			feed.instance();
+			feed->set_name("ARKit");
+
+			CameraServer *cs = CameraServer::get_singleton();
+			if (cs != NULL) {
+				cs->add_feed(feed);
+			}
+		}
+		feed->set_active(true);
+
+		// yeah!
+		initialized = true;
+
+		// Start our session...
+		start_session();
+	}
+
+	return true;
+}
+
+void ARKitInterface::uninitialize() {
+	if (initialized) {
+		ARVRServer *arvr_server = ARVRServer::get_singleton();
+		if (arvr_server != NULL) {
+			// no longer our primary interface
+			arvr_server->clear_primary_interface_if(this);
+		}
+
+		if (feed.is_valid()) {
+			CameraServer *cs = CameraServer::get_singleton();
+			if ((cs != NULL)) {
+				cs->remove_feed(feed);
+			}
+			feed.unref();
+		}
+
+		remove_all_anchors();
+
+		[ar_session release];
+		[ar_delegate release];
+		ar_session = NULL;
+		ar_delegate = NULL;
+		initialized = false;
+		session_was_started = false;
+	}
+}
+
+Size2 ARKitInterface::get_render_targetsize() {
+	_THREAD_SAFE_METHOD_
+
+	Size2 target_size = OS::get_singleton()->get_window_size();
+
+	return target_size;
+}
+
+Transform ARKitInterface::get_transform_for_eye(ARVRInterface::Eyes p_eye, const Transform &p_cam_transform) {
+	_THREAD_SAFE_METHOD_
+
+	Transform transform_for_eye;
+
+	ARVRServer *arvr_server = ARVRServer::get_singleton();
+	ERR_FAIL_NULL_V(arvr_server, transform_for_eye);
+
+	if (initialized) {
+		float world_scale = arvr_server->get_world_scale();
+
+		// just scale our origin point of our transform, note that we really shouldn't be using world_scale in ARKit but....
+		transform_for_eye = transform;
+		transform_for_eye.origin *= world_scale;
+
+		transform_for_eye = p_cam_transform * arvr_server->get_reference_frame() * transform_for_eye;
+	} else {
+		// huh? well just return what we got....
+		transform_for_eye = p_cam_transform;
+	}
+
+	return transform_for_eye;
+}
+
+CameraMatrix ARKitInterface::get_projection_for_eye(ARVRInterface::Eyes p_eye, real_t p_aspect, real_t p_z_near, real_t p_z_far) {
+	// Remember our near and far, it will be used in process when we obtain our projection from our ARKit session.
+	z_near = p_z_near;
+	z_far = p_z_far;
+
+	return projection;
+}
+
+void ARKitInterface::commit_for_eye(ARVRInterface::Eyes p_eye, RID p_render_target, const Rect2 &p_screen_rect) {
+	_THREAD_SAFE_METHOD_
+
+	// We must have a valid render target
+	ERR_FAIL_COND(!p_render_target.is_valid());
+
+	// Because we are rendering to our device we must use our main viewport!
+	ERR_FAIL_COND(p_screen_rect == Rect2());
+
+	// get the size of our screen
+	Rect2 screen_rect = p_screen_rect;
+
+	//		screen_rect.position.x += screen_rect.size.x;
+	//		screen_rect.size.x = -screen_rect.size.x;
+	//		screen_rect.position.y += screen_rect.size.y;
+	//		screen_rect.size.y = -screen_rect.size.y;
+
+	VSG::rasterizer->set_current_render_target(RID());
+	VSG::rasterizer->blit_render_target_to_screen(p_render_target, screen_rect, 0);
+}
+
+ARVRPositionalTracker *ARKitInterface::get_anchor_for_uuid(const unsigned char *p_uuid) {
+	if (anchors == NULL) {
+		num_anchors = 0;
+		max_anchors = 10;
+		anchors = (anchor_map *)malloc(sizeof(anchor_map) * max_anchors);
+	}
+
+	ERR_FAIL_NULL_V(anchors, NULL);
+
+	for (unsigned int i = 0; i < num_anchors; i++) {
+		if (memcmp(anchors[i].uuid, p_uuid, 16) == 0) {
+			return anchors[i].tracker;
+		}
+	}
+
+	if (num_anchors + 1 == max_anchors) {
+		max_anchors += 10;
+		anchors = (anchor_map *)realloc(anchors, sizeof(anchor_map) * max_anchors);
+		ERR_FAIL_NULL_V(anchors, NULL);
+	}
+
+	ARVRPositionalTracker *new_tracker = memnew(ARVRPositionalTracker);
+	new_tracker->set_type(ARVRServer::TRACKER_ANCHOR);
+
+	char tracker_name[256];
+	sprintf(tracker_name, "Anchor %02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", p_uuid[0], p_uuid[1], p_uuid[2], p_uuid[3], p_uuid[4], p_uuid[5], p_uuid[6], p_uuid[7], p_uuid[8], p_uuid[9], p_uuid[10], p_uuid[11], p_uuid[12], p_uuid[13], p_uuid[14], p_uuid[15]);
+
+	String name = tracker_name;
+	print_line("Adding tracker " + name);
+	new_tracker->set_name(name);
+
+	// add our tracker
+	ARVRServer::get_singleton()->add_tracker(new_tracker);
+	anchors[num_anchors].tracker = new_tracker;
+	memcpy(anchors[num_anchors].uuid, p_uuid, 16);
+	num_anchors++;
+
+	return new_tracker;
+}
+
+void ARKitInterface::remove_anchor_for_uuid(const unsigned char *p_uuid) {
+	if (anchors != NULL) {
+		for (unsigned int i = 0; i < num_anchors; i++) {
+			if (memcmp(anchors[i].uuid, p_uuid, 16) == 0) {
+				// remove our tracker
+				ARVRServer::get_singleton()->remove_tracker(anchors[i].tracker);
+				memdelete(anchors[i].tracker);
+
+				// bring remaining forward
+				for (unsigned int j = i + 1; j < num_anchors; j++) {
+					anchors[j - 1] = anchors[j];
+				};
+
+				// decrease count
+				num_anchors--;
+				return;
+			}
+		}
+	}
+}
+
+void ARKitInterface::remove_all_anchors() {
+	if (anchors != NULL) {
+		for (unsigned int i = 0; i < num_anchors; i++) {
+			// remove our tracker
+			ARVRServer::get_singleton()->remove_tracker(anchors[i].tracker);
+			memdelete(anchors[i].tracker);
+		};
+
+		free(anchors);
+		anchors = NULL;
+		num_anchors = 0;
+	}
+}
+
+void ARKitInterface::process() {
+	_THREAD_SAFE_METHOD_
+
+	if (@available(iOS 11.0, *)) {
+		if (initialized) {
+			// get our next ARFrame
+			ARFrame *current_frame = ar_session.currentFrame;
+			if (last_timestamp != current_frame.timestamp) {
+				// only process if we have a new frame
+				last_timestamp = current_frame.timestamp;
+
+				// get some info about our screen and orientation
+				Size2 screen_size = OS::get_singleton()->get_window_size();
+				UIDeviceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation];
+
+				// Grab our camera image for our backbuffer
+				CVPixelBufferRef pixelBuffer = current_frame.capturedImage;
+				if ((CVPixelBufferGetPlaneCount(pixelBuffer) == 2) && (feed != NULL)) {
+					// Plane 0 is our Y and Plane 1 is our CbCr buffer
+
+					// ignored, we check each plane separately
+					// image_width = CVPixelBufferGetWidth(pixelBuffer);
+					// image_height = CVPixelBufferGetHeight(pixelBuffer);
+
+					// printf("Pixel buffer %i - %i\n", image_width, image_height);
+
+					CVPixelBufferLockBaseAddress(pixelBuffer, kCVPixelBufferLock_ReadOnly);
+
+					// get our buffers
+					unsigned char *dataY = (unsigned char *)CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0);
+					unsigned char *dataCbCr = (unsigned char *)CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 1);
+
+					if (dataY == NULL) {
+						print_line("Couldn't access Y pixel buffer data");
+					} else if (dataCbCr == NULL) {
+						print_line("Couldn't access CbCr pixel buffer data");
+					} else {
+						Ref<Image> img[2];
+						size_t extraLeft, extraRight, extraTop, extraBottom;
+
+						CVPixelBufferGetExtendedPixels(pixelBuffer, &extraLeft, &extraRight, &extraTop, &extraBottom);
+
+						{
+							// do Y
+							int new_width = CVPixelBufferGetWidthOfPlane(pixelBuffer, 0);
+							int new_height = CVPixelBufferGetHeightOfPlane(pixelBuffer, 0);
+							int bytes_per_row = CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 0);
+
+							if ((image_width[0] != new_width) || (image_height[0] != new_height)) {
+								printf("- Camera padding l:%lu r:%lu t:%lu b:%lu\n", extraLeft, extraRight, extraTop, extraBottom);
+								printf("- Camera Y plane size: %i, %i - %i\n", new_width, new_height, bytes_per_row);
+
+								image_width[0] = new_width;
+								image_height[0] = new_height;
+								img_data[0].resize(new_width * new_height);
+							}
+
+							PoolVector<uint8_t>::Write w = img_data[0].write();
+							if (new_width == bytes_per_row) {
+								memcpy(w.ptr(), dataY, new_width * new_height);
+							} else {
+								int offset_a = 0;
+								int offset_b = extraLeft + (extraTop * bytes_per_row);
+								for (int r = 0; r < new_height; r++) {
+									memcpy(w.ptr() + offset_a, dataY + offset_b, new_width);
+									offset_a += new_width;
+									offset_b += bytes_per_row;
+								}
+							}
+
+							img[0].instance();
+							img[0]->create(new_width, new_height, 0, Image::FORMAT_R8, img_data[0]);
+						}
+
+						{
+							// do CbCr
+							int new_width = CVPixelBufferGetWidthOfPlane(pixelBuffer, 1);
+							int new_height = CVPixelBufferGetHeightOfPlane(pixelBuffer, 1);
+							int bytes_per_row = CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 0);
+
+							if ((image_width[1] != new_width) || (image_height[1] != new_height)) {
+								printf("- Camera CbCr plane size: %i, %i - %i\n", new_width, new_height, bytes_per_row);
+
+								image_width[1] = new_width;
+								image_height[1] = new_height;
+								img_data[1].resize(2 * new_width * new_height);
+							}
+
+							PoolVector<uint8_t>::Write w = img_data[1].write();
+							if ((2 * new_width) == bytes_per_row) {
+								memcpy(w.ptr(), dataCbCr, 2 * new_width * new_height);
+							} else {
+								int offset_a = 0;
+								int offset_b = extraLeft + (extraTop * bytes_per_row);
+								for (int r = 0; r < new_height; r++) {
+									memcpy(w.ptr() + offset_a, dataCbCr + offset_b, 2 * new_width);
+									offset_a += 2 * new_width;
+									offset_b += bytes_per_row;
+								}
+							}
+
+							img[1].instance();
+							img[1]->create(new_width, new_height, 0, Image::FORMAT_RG8, img_data[1]);
+						}
+
+						// set our texture...
+						feed->set_YCbCr_imgs(img[0], img[1]);
+
+						// now build our transform to display this as a background image that matches our camera
+						CGAffineTransform affine_transform = [current_frame displayTransformForOrientation:orientation viewportSize:CGSizeMake(screen_size.width, screen_size.height)];
+
+						// we need to invert this, probably row v.s. column notation
+						affine_transform = CGAffineTransformInvert(affine_transform);
+
+						if (orientation != UIDeviceOrientationPortrait) {
+							affine_transform.b = -affine_transform.b;
+							affine_transform.d = -affine_transform.d;
+							affine_transform.ty = 1.0 - affine_transform.ty;
+						} else {
+							affine_transform.c = -affine_transform.c;
+							affine_transform.a = -affine_transform.a;
+							affine_transform.tx = 1.0 - affine_transform.tx;
+						}
+
+						Transform2D display_transform = Transform2D(
+								affine_transform.a, affine_transform.b,
+								affine_transform.c, affine_transform.d,
+								affine_transform.tx, affine_transform.ty);
+
+						feed->set_transform(display_transform);
+					}
+
+					// and unlock
+					CVPixelBufferUnlockBaseAddress(pixelBuffer, kCVPixelBufferLock_ReadOnly);
+				}
+
+				// Record light estimation to apply to our scene
+				if (light_estimation_is_enabled) {
+					ambient_intensity = current_frame.lightEstimate.ambientIntensity;
+
+					///@TODO it's there, but not there.. what to do with this...
+					// https://developer.apple.com/documentation/arkit/arlightestimate?language=objc
+					//				ambient_color_temperature = current_frame.lightEstimate.ambientColorTemperature;
+				}
+
+				// Process our camera
+				ARCamera *camera = current_frame.camera;
+
+				// strangely enough we have to states, rolling them up into one
+				if (camera.trackingState == ARTrackingStateNotAvailable) {
+					// no tracking, would be good if we black out the screen or something...
+					tracking_state = ARVRInterface::ARVR_NOT_TRACKING;
+				} else {
+					if (camera.trackingState == ARTrackingStateNormal) {
+						tracking_state = ARVRInterface::ARVR_NORMAL_TRACKING;
+					} else if (camera.trackingStateReason == ARTrackingStateReasonExcessiveMotion) {
+						tracking_state = ARVRInterface::ARVR_EXCESSIVE_MOTION;
+					} else if (camera.trackingStateReason == ARTrackingStateReasonInsufficientFeatures) {
+						tracking_state = ARVRInterface::ARVR_INSUFFICIENT_FEATURES;
+					} else {
+						tracking_state = ARVRInterface::ARVR_UNKNOWN_TRACKING;
+					}
+
+					// copy our current frame transform
+					matrix_float4x4 m44 = camera.transform;
+					if (orientation == UIDeviceOrientationLandscapeLeft) {
+						transform.basis.elements[0].x = m44.columns[0][0];
+						transform.basis.elements[1].x = m44.columns[0][1];
+						transform.basis.elements[2].x = m44.columns[0][2];
+						transform.basis.elements[0].y = m44.columns[1][0];
+						transform.basis.elements[1].y = m44.columns[1][1];
+						transform.basis.elements[2].y = m44.columns[1][2];
+					} else if (orientation == UIDeviceOrientationPortrait) {
+						transform.basis.elements[0].x = m44.columns[1][0];
+						transform.basis.elements[1].x = m44.columns[1][1];
+						transform.basis.elements[2].x = m44.columns[1][2];
+						transform.basis.elements[0].y = -m44.columns[0][0];
+						transform.basis.elements[1].y = -m44.columns[0][1];
+						transform.basis.elements[2].y = -m44.columns[0][2];
+					} else if (orientation == UIDeviceOrientationLandscapeRight) {
+						transform.basis.elements[0].x = -m44.columns[0][0];
+						transform.basis.elements[1].x = -m44.columns[0][1];
+						transform.basis.elements[2].x = -m44.columns[0][2];
+						transform.basis.elements[0].y = -m44.columns[1][0];
+						transform.basis.elements[1].y = -m44.columns[1][1];
+						transform.basis.elements[2].y = -m44.columns[1][2];
+					} else if (orientation == UIDeviceOrientationPortraitUpsideDown) {
+						// this may not be correct
+						transform.basis.elements[0].x = m44.columns[1][0];
+						transform.basis.elements[1].x = m44.columns[1][1];
+						transform.basis.elements[2].x = m44.columns[1][2];
+						transform.basis.elements[0].y = m44.columns[0][0];
+						transform.basis.elements[1].y = m44.columns[0][1];
+						transform.basis.elements[2].y = m44.columns[0][2];
+					}
+					transform.basis.elements[0].z = m44.columns[2][0];
+					transform.basis.elements[1].z = m44.columns[2][1];
+					transform.basis.elements[2].z = m44.columns[2][2];
+					transform.origin.x = m44.columns[3][0];
+					transform.origin.y = m44.columns[3][1];
+					transform.origin.z = m44.columns[3][2];
+
+					// copy our current frame projection, investigate using projectionMatrixWithViewportSize:orientation:zNear:zFar: so we can set our own near and far
+					m44 = [camera projectionMatrixForOrientation:orientation viewportSize:CGSizeMake(screen_size.width, screen_size.height) zNear:z_near zFar:z_far];
+					projection.matrix[0][0] = m44.columns[0][0];
+					projection.matrix[1][0] = m44.columns[1][0];
+					projection.matrix[2][0] = m44.columns[2][0];
+					projection.matrix[3][0] = m44.columns[3][0];
+					projection.matrix[0][1] = m44.columns[0][1];
+					projection.matrix[1][1] = m44.columns[1][1];
+					projection.matrix[2][1] = m44.columns[2][1];
+					projection.matrix[3][1] = m44.columns[3][1];
+					projection.matrix[0][2] = m44.columns[0][2];
+					projection.matrix[1][2] = m44.columns[1][2];
+					projection.matrix[2][2] = m44.columns[2][2];
+					projection.matrix[3][2] = m44.columns[3][2];
+					projection.matrix[0][3] = m44.columns[0][3];
+					projection.matrix[1][3] = m44.columns[1][3];
+					projection.matrix[2][3] = m44.columns[2][3];
+					projection.matrix[3][3] = m44.columns[3][3];
+				}
+			}
+		}
+	}
+}
+
+void ARKitInterface::_add_or_update_anchor(void *p_anchor) {
+	_THREAD_SAFE_METHOD_
+
+	ARAnchor *anchor = (ARAnchor *)p_anchor;
+
+	unsigned char uuid[16];
+	[anchor.identifier getUUIDBytes:uuid];
+
+	ARVRPositionalTracker *tracker = get_anchor_for_uuid(uuid);
+	if (tracker != NULL) {
+		// lets update our mesh! (using Arjens code as is for now)
+		// we should also probably limit how often we do this...
+
+		// can we safely cast this?
+		ARPlaneAnchor *planeAnchor = (ARPlaneAnchor *)anchor;
+
+		if (planeAnchor.geometry.triangleCount > 0) {
+			Ref<SurfaceTool> surftool;
+			surftool.instance();
+			surftool->begin(Mesh::PRIMITIVE_TRIANGLES);
+
+			for (int j = planeAnchor.geometry.triangleCount * 3 - 1; j >= 0; j--) {
+				int16_t index = planeAnchor.geometry.triangleIndices[j];
+				simd_float3 vrtx = planeAnchor.geometry.vertices[index];
+				simd_float2 textcoord = planeAnchor.geometry.textureCoordinates[index];
+				surftool->add_uv(Vector2(textcoord[0], textcoord[1]));
+				surftool->add_color(Color(0.8, 0.8, 0.8));
+				surftool->add_vertex(Vector3(vrtx[0], vrtx[1], vrtx[2]));
+			}
+
+			surftool->generate_normals();
+			tracker->set_mesh(surftool->commit());
+		} else {
+			Ref<Mesh> nomesh;
+			tracker->set_mesh(nomesh);
+		}
+
+		// Note, this also contains a scale factor which gives us an idea of the size of the anchor
+		// We may extract that in our ARVRAnchor class
+		Basis b;
+		matrix_float4x4 m44 = anchor.transform;
+		b.elements[0].x = m44.columns[0][0];
+		b.elements[1].x = m44.columns[0][1];
+		b.elements[2].x = m44.columns[0][2];
+		b.elements[0].y = m44.columns[1][0];
+		b.elements[1].y = m44.columns[1][1];
+		b.elements[2].y = m44.columns[1][2];
+		b.elements[0].z = m44.columns[2][0];
+		b.elements[1].z = m44.columns[2][1];
+		b.elements[2].z = m44.columns[2][2];
+		tracker->set_orientation(b);
+		tracker->set_rw_position(Vector3(m44.columns[3][0], m44.columns[3][1], m44.columns[3][2]));
+	}
+}
+
+void ARKitInterface::_remove_anchor(void *p_anchor) {
+	_THREAD_SAFE_METHOD_
+
+	ARAnchor *anchor = (ARAnchor *)p_anchor;
+
+	unsigned char uuid[16];
+	[anchor.identifier getUUIDBytes:uuid];
+
+	remove_anchor_for_uuid(uuid);
+}
+
+ARKitInterface::ARKitInterface() {
+	initialized = false;
+	session_was_started = false;
+	plane_detection_is_enabled = false;
+	light_estimation_is_enabled = false;
+	ar_session = NULL;
+	z_near = 0.01;
+	z_far = 1000.0;
+	projection.set_perspective(60.0, 1.0, z_near, z_far, false);
+	anchors = NULL;
+	num_anchors = 0;
+	ambient_intensity = 1.0;
+	ambient_color_temperature = 1.0;
+	image_width[0] = 0;
+	image_width[1] = 0;
+	image_height[0] = 0;
+	image_height[1] = 0;
+}
+
+ARKitInterface::~ARKitInterface() {
+	remove_all_anchors();
+
+	// and make sure we cleanup if we haven't already
+	if (is_initialized()) {
+		uninitialize();
+	}
+}
diff --git a/modules/arkit/arkit_session_delegate.h b/modules/arkit/arkit_session_delegate.h
new file mode 100644
index 0000000000..afe093656b
--- /dev/null
+++ b/modules/arkit/arkit_session_delegate.h
@@ -0,0 +1,50 @@
+/*************************************************************************/
+/*  arkit_session_delegate.h                                             */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                    http://www.godotengine.org                         */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef ARKIT_SESSION_DELEGATE_H
+#define ARKIT_SESSION_DELEGATE_H
+
+#import <ARKit/ARKit.h>
+#import <UIKit/UIKit.h>
+
+class ARKitInterface;
+
+@interface ARKitSessionDelegate : NSObject <ARSessionDelegate> {
+	ARKitInterface *arkit_interface;
+}
+
+@property(nonatomic) ARKitInterface *arkit_interface;
+
+- (void)session:(ARSession *)session didAddAnchors:(NSArray<ARAnchor *> *)anchors;
+- (void)session:(ARSession *)session didRemoveAnchors:(NSArray<ARAnchor *> *)anchors;
+- (void)session:(ARSession *)session didUpdateAnchors:(NSArray<ARAnchor *> *)anchors;
+@end
+
+#endif /* !ARKIT_SESSION_DELEGATE_H */
diff --git a/modules/arkit/arkit_session_delegate.mm b/modules/arkit/arkit_session_delegate.mm
new file mode 100644
index 0000000000..56485c987c
--- /dev/null
+++ b/modules/arkit/arkit_session_delegate.mm
@@ -0,0 +1,56 @@
+/*************************************************************************/
+/*  arkit_session_delegate.mm                                            */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                    http://www.godotengine.org                         */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "arkit_session_delegate.h"
+#include "arkit_interface.h"
+
+@implementation ARKitSessionDelegate
+
+@synthesize arkit_interface;
+
+- (void)session:(ARSession *)session didAddAnchors:(NSArray<ARAnchor *> *)anchors {
+	for (ARAnchor *anchor in anchors) {
+		arkit_interface->_add_or_update_anchor(anchor);
+	}
+}
+
+- (void)session:(ARSession *)session didRemoveAnchors:(NSArray<ARAnchor *> *)anchors {
+	for (ARAnchor *anchor in anchors) {
+		arkit_interface->_remove_anchor(anchor);
+	}
+}
+
+- (void)session:(ARSession *)session didUpdateAnchors:(NSArray<ARAnchor *> *)anchors {
+	for (ARAnchor *anchor in anchors) {
+		arkit_interface->_add_or_update_anchor(anchor);
+	}
+}
+
+@end
\ No newline at end of file
diff --git a/modules/arkit/config.py b/modules/arkit/config.py
new file mode 100644
index 0000000000..96e41826c5
--- /dev/null
+++ b/modules/arkit/config.py
@@ -0,0 +1,5 @@
+def can_build(env, platform):
+    return platform == 'iphone'
+
+def configure(env):
+    pass
diff --git a/modules/arkit/register_types.cpp b/modules/arkit/register_types.cpp
new file mode 100644
index 0000000000..af35828004
--- /dev/null
+++ b/modules/arkit/register_types.cpp
@@ -0,0 +1,45 @@
+/*************************************************************************/
+/*  register_types.cpp                                                   */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2019 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "register_types.h"
+
+#include "arkit_interface.h"
+
+void register_arkit_types() {
+	// does it make sense to register the class?
+
+	Ref<ARKitInterface> arkit_interface;
+	arkit_interface.instance();
+	ARVRServer::get_singleton()->add_interface(arkit_interface);
+}
+
+void unregister_arkit_types() {
+	// should clean itself up nicely :)
+}
diff --git a/modules/arkit/register_types.h b/modules/arkit/register_types.h
new file mode 100644
index 0000000000..6ed2065de2
--- /dev/null
+++ b/modules/arkit/register_types.h
@@ -0,0 +1,32 @@
+/*************************************************************************/
+/*  register_types.h                                                     */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2019 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+void register_arkit_types();
+void unregister_arkit_types();