This PR adds support for VR to the _gamnit depth_ framework. By importing `gamnit::vr`, all drawings are duplicated for a stereoscopic view and the `world_camera` orientation is updated from head tracking data.
VR is applied to the `model_viewer` app for testing only. The UI should still be updated for a nicer VR experience.
This is done by simple refinement, which allows for easy (but dirty) conversion to VR using `nitc ... -m lib/gamnit/depth/vr.nit`. However this does not allow to easily switch between VR and a classic view. This could be improved as needed in the future by using a subclass of `EulerCamera` and a few conditions in `frame_core_draw`.
Pull-Request: #1923
Reviewed-by: Jean Privat <jean@pryen.org>
convert -resize 96x96 art/icon.png res/drawable-xhdpi/icon.png
convert -resize 144x144 art/icon.png res/drawable-xxhdpi/icon.png
convert -resize 192x192 art/icon.png res/drawable-xxxhdpi/icon.png
+
+bin/model_viewer_vr.apk: $(shell ${NITLS} -M src/model_viewer.nit android) ${NITC} res/drawable-hdpi/icon.png libs/cardboard.jar
+ ${NITC} src/model_viewer.nit -m android -m ../../lib/gamnit/depth/vr.nit -o $@
+
+libs/cardboard.jar:
+ curl --progress-bar -o libs/cardboard.jar \
+ https://raw.githubusercontent.com/googlesamples/cardboard-java/master/CardboardSample/libs/cardboard.jar
# Stop tracking head movement
fun stop_tracking in "Java" `{ self.stopTracking(); `}
- # Apply correction to the gyroscope values
- fun gyro_bias=(matrix: JavaFloatArray) in "Java" `{
- self.setGyroBias(matrix);
- `}
-
# Enable finer analysis using the neck as center of movement
fun neck_model_enabled=(value: Bool) in "Java" `{
self.setNeckModelEnabled(value);
--- /dev/null
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Update the orientation of `world_camera` at each frame using the head position given by `android::cardboard`
+#
+# This module is Android specific.
+module cardboard
+
+import ::android::cardboard
+
+import depth
+intrude import cameras
+
+redef class EulerCamera
+ # Do not use `yaw` and `pitch`, the value will instead originate from the Cardboard API
+ redef var rotation_matrix = new Matrix.identity(4)
+
+ # Get the angle value from the `rotation_matrix`
+ redef fun pitch
+ do
+ var a = rotation_matrix[0, 1]
+ var b = rotation_matrix[1, 1]
+ return -atan2(a, b)
+ end
+
+ # Get the angle value from the `rotation_matrix`
+ redef fun yaw
+ do
+ var a = rotation_matrix[2, 0]
+ var b = rotation_matrix[2, 2]
+ return -atan2(a, b)
+ end
+end
+
+redef class App
+
+ # Cardboard's head tacker instance
+ private var head_tracker: nullable NativeHeadTracker = null
+
+ # Rotation matrix read from `head_tracker`, reusing the same structure as a buffer
+ private var java_rotation_matrix = new JavaFloatArray(16) is lazy
+
+ # Initialize and set `head_tracker`
+ fun initialize_head_tracker
+ do
+ # Initialize the Cardboard head orientation tracker service
+ var head_tracker = new NativeHeadTracker(app.native_activity)
+ head_tracker.neck_model_enabled = true
+ head_tracker.start_tracking
+ self.head_tracker = head_tracker
+
+ # Set a wide field of view
+ world_camera.field_of_view_y = 1.0
+ end
+
+ # Read the rotation matrix from Cardboard and update `world_camera`
+ private fun update_from_head_tracker
+ do
+ var head_tracker = head_tracker
+ if head_tracker == null then return
+
+ head_tracker.last_head_view(java_rotation_matrix, 0)
+
+ # Copy values from the Java array to our matrix
+ for y in [0..4[ do
+ for x in [0..4[ do
+ world_camera.rotation_matrix[y, x] = java_rotation_matrix[y*4+x]
+ end
+ end
+ end
+
+ redef fun on_create
+ do
+ super
+ initialize_head_tracker
+ end
+
+ redef fun update(dt)
+ do
+ super
+ update_from_head_tracker
+ end
+
+ redef fun pause
+ do
+ super
+ var tracker = head_tracker
+ if tracker != null then tracker.stop_tracking
+ end
+
+ redef fun resume
+ do
+ super
+ var tracker = head_tracker
+ if tracker != null then tracker.start_tracking
+ end
+end
assert gamnit_error == null else print_error gamnit_error
end
- # Draw all element in `actors`
- redef fun frame_core_draw(display)
- do
- super
+ redef fun frame_core_draw(display) do frame_core_depth display
+ # Draw all elements of `actors` and then call `frame_core_flat`
+ protected fun frame_core_depth(display: GamnitDisplay)
+ do
# Update cameras on both our programs
versatile_program.use
versatile_program.mvp.uniform world_camera.mvp_matrix
leaf.material.draw(actor, leaf)
end
end
+
+ frame_core_flat display
end
end
--- /dev/null
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Refine `EulerCamera` and `App::frame_core_draw` to get a stereoscopic view
+module stereoscopic_view
+
+import depth
+intrude import cameras
+
+redef class EulerCamera
+ redef var mvp_matrix = new Matrix.identity(4)
+
+ # Half of the distance between the eyes
+ var eye_separation: Float = 0.03125
+
+ # MVP matrix for the left eye
+ fun mvp_matrix_left: Matrix do return mvp_matrix_eye(eye_separation)
+
+ # MVP matrix for the right eye
+ fun mvp_matrix_right: Matrix do return mvp_matrix_eye(-eye_separation)
+
+ # Get an MVP matrix for an eye at `diff` world unit from the center
+ private fun mvp_matrix_eye(diff: Float): Matrix
+ do
+ var view = new Matrix.identity(4)
+
+ # Translate the world away from the camera
+ view.translate(-position.x/2.0, -position.y/2.0, -position.z/2.0)
+
+ # Rotate the camera, first by looking left or right, then up or down
+ view = view * rotation_matrix
+
+ # Apply eye transformation
+ var translation = new Matrix.identity(4)
+ translation.translate(diff, 0.0, 0.0)
+ view = view * translation
+
+ # Use a projection matrix with a depth
+ var projection = new Matrix.perspective(pi*field_of_view_y/2.0,
+ display.aspect_ratio, near, far)
+
+ return view * projection
+ end
+end
+
+redef class GamnitDisplay
+
+ # With stereoscopic view, the aspect ratio (in each eye) is half of the screen
+ redef fun aspect_ratio do return super / 2.0
+end
+
+redef class App
+ redef fun frame_core_draw(display) do frame_core_stereoscopic display
+
+ # Split the screen in two, and call `frame_core_depth` for each eyes
+ protected fun frame_core_stereoscopic(display: GamnitDisplay)
+ do
+ var half_width = display.width / 2
+
+ # Left eye
+ glViewport(0, 0, half_width, display.height)
+ world_camera.mvp_matrix = world_camera.mvp_matrix_left
+ frame_core_depth display
+
+ # Right eye
+ glViewport(half_width, 0, half_width, display.height)
+ world_camera.mvp_matrix = world_camera.mvp_matrix_right
+ frame_core_depth display
+
+ # We reset the viewport for selection
+ glViewport(0, 0, display.width, display.height)
+
+ # Check for errors
+ var gl_error = glGetError
+ assert gl_error == gl_NO_ERROR else print gl_error
+ end
+end
--- /dev/null
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# VR support for gamnit depth, for Android only
+module vr
+
+import cardboard
+import stereoscopic_view
assert gl_error == gl_NO_ERROR else print gl_error
end
+ # Draw the whole screen, all `glDraw...` calls should be executed here
+ protected fun frame_core_draw(display: GamnitDisplay) do frame_core_flat display
+
# Draw sprites in `sprites` and `ui_sprites`
- protected fun frame_core_draw(display: GamnitDisplay)
+ protected fun frame_core_flat(display: GamnitDisplay)
do
simple_2d_program.use
nitlanguage / nit.git / commitdiff