matrixfurry.com
The open source OpenXR runtime
d/android: adds support for loading cardboard calibration files
Co-authored-by: Simon Zeni <simon.zeni@collabora.com>
Co-authored-by: Rylie Pavlik <rylie.pavlik@collabora.com>
Part-of: <https://gitlab.freedesktop.org/monado/monado/-/merge_requests/2560>
+1
.reuse/dep5
+1
.reuse/dep5
···
138
Comment: Computer-generated files do not have a copyright per US law.
139
140
Files: src/xrt/auxiliary/android_cardboard/src/main/res/drawable/cardboard_oss_qr.png
141
+
src/external/cardboard/*
142
Copyright: 2019 Google LLC
143
License: Apache-2.0
144
Comment: SPDX-License-Identifier missing.
+13
-1
src/external/CMakeLists.txt
+13
-1
src/external/CMakeLists.txt
···
1
+
# Copyright 2020-2025, Collabora, Ltd.
2
# SPDX-License-Identifier: BSL-1.0
3
4
# Catch2
···
82
nanopb/pb_encode.h
83
)
84
target_include_directories(xrt-external-nanopb PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/nanopb)
85
+
86
+
if(ANDROID)
87
+
add_library(
88
+
xrt-external-cardboard STATIC cardboard/cardboard_device.pb.h
89
+
cardboard/cardboard_device.pb.c
90
+
)
91
+
92
+
target_include_directories(
93
+
xrt-external-cardboard PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/cardboard/
94
+
)
95
+
target_link_libraries(xrt-external-cardboard PUBLIC xrt-external-nanopb)
96
+
endif()
97
98
# OpenXR
99
add_library(xrt-external-openxr INTERFACE)
+16
src/external/cardboard/cardboard_device.pb.c
+16
src/external/cardboard/cardboard_device.pb.c
···
···
1
+
/* Automatically generated nanopb constant definitions */
2
+
/* Generated by nanopb-0.4.9.1 */
3
+
4
+
#include "cardboard_device.pb.h"
5
+
#if PB_PROTO_HEADER_VERSION != 40
6
+
#error Regenerate this file with the current version of nanopb generator.
7
+
#endif
8
+
9
+
PB_BIND(cardboard_DeviceParams, cardboard_DeviceParams, AUTO)
10
+
11
+
12
+
13
+
14
+
15
+
16
+
+170
src/external/cardboard/cardboard_device.pb.h
+170
src/external/cardboard/cardboard_device.pb.h
···
···
1
+
/* Automatically generated nanopb header */
2
+
/* Generated by nanopb-0.4.9.1 */
3
+
4
+
#ifndef PB_CARDBOARD_CARDBOARD_DEVICE_PB_H_INCLUDED
5
+
#define PB_CARDBOARD_CARDBOARD_DEVICE_PB_H_INCLUDED
6
+
#include <pb.h>
7
+
8
+
#if PB_PROTO_HEADER_VERSION != 40
9
+
#error Regenerate this file with the current version of nanopb generator.
10
+
#endif
11
+
12
+
/* Enum definitions */
13
+
typedef enum _cardboard_DeviceParams_VerticalAlignmentType {
14
+
cardboard_DeviceParams_VerticalAlignmentType_BOTTOM = 0, /* phone rests against a fixed bottom tray */
15
+
cardboard_DeviceParams_VerticalAlignmentType_CENTER = 1, /* phone screen assumed to be centered w.r.t. lenses */
16
+
cardboard_DeviceParams_VerticalAlignmentType_TOP = 2 /* phone rests against a fixed top tray */
17
+
} cardboard_DeviceParams_VerticalAlignmentType;
18
+
19
+
typedef enum _cardboard_DeviceParams_ButtonType {
20
+
/* No physical button, and touch screen is not easily accessible. */
21
+
cardboard_DeviceParams_ButtonType_NONE = 0,
22
+
/* HMD has integrated magnet switch similar to original Cardboard. */
23
+
cardboard_DeviceParams_ButtonType_MAGNET = 1,
24
+
/* At least a portion of touch screen is easily accessible to user for taps. */
25
+
cardboard_DeviceParams_ButtonType_TOUCH = 2,
26
+
/* Touch screen is triggered indirectly via integrated button on the HMD. */
27
+
cardboard_DeviceParams_ButtonType_INDIRECT_TOUCH = 3
28
+
} cardboard_DeviceParams_ButtonType;
29
+
30
+
/* Struct definitions */
31
+
/* *
32
+
Message describing properties of a VR head mount device (HMD) which uses an
33
+
interchangeable smartphone as a display (e.g. Google Cardboard).
34
+
35
+
While some properties are certain (e.g. inter_lens_distance), others
36
+
represent nominal values which may be refined depending on context (e.g.
37
+
viewport_angles).
38
+
39
+
Lengths are in meters unless noted otherwise. Fields are _required_
40
+
unless noted otherwise.
41
+
42
+
Some context on why this set of parameters are deemed necessary and
43
+
sufficient:
44
+
* FOV scale can be reasonably approximated from lens-to-screen distance
45
+
and display size (i.e. knowing lens focal length isn't crucial).
46
+
* Lenses are assumed to be horizontally centered with respect to
47
+
display.
48
+
* The display is not necessarily vertically centered. For interchangeable
49
+
phones where the device rests against a tray, we can derive
50
+
the vertical offset from tray-to-lens height along with phone-specific
51
+
bezel and screen sizes (supplied separately). */
52
+
typedef struct _cardboard_DeviceParams {
53
+
/* String identifying the device's vendor (e.g. "Google, Inc.").
54
+
A device's [vendor, model] pair is expected to be globally unique. */
55
+
pb_callback_t vendor;
56
+
/* String identifying the device's model, including revision info if
57
+
needed (e.g. "Cardboard v1"). A device's [vendor, model] pair is
58
+
expected to be globally unique. */
59
+
pb_callback_t model;
60
+
/* Distance from the display screen to the optical center of lenses.
61
+
This is a required field for distortion rendering, and must be positive. */
62
+
bool has_screen_to_lens_distance;
63
+
float screen_to_lens_distance;
64
+
/* Horizontal distance between optical center of the lenses.
65
+
This is a required field for distortion rendering, and must be positive. */
66
+
bool has_inter_lens_distance;
67
+
float inter_lens_distance;
68
+
/* Four-element tuple (left, right, bottom, top) of left eye's view extent
69
+
angles relative to center, assuming the following:
70
+
* eye is aligned with optical center of lens
71
+
* display screen is equal or larger than extents viewable through lens
72
+
* nominal eye-to-lens distance
73
+
* mirrored field of view will be applied to the right eye
74
+
These values are essentially used as an optimization to avoid rendering
75
+
pixels which can't be seen.
76
+
This is a required field for distortion rendering, and angles must be
77
+
positive. */
78
+
pb_callback_t left_eye_field_of_view_angles;
79
+
/* If the phone is aligned vertically within the device by resting against
80
+
a fixed top or bottom tray, this is the distance from the tray to
81
+
optical center of the lenses.
82
+
This is a required field for distortion rendering, and must be positive.
83
+
NOTE: Due to a bug in initial versions of the SDK's, this field
84
+
must be set explicitly to .035 when vertical_alignment = CENTER. */
85
+
bool has_tray_to_lens_distance;
86
+
float tray_to_lens_distance;
87
+
/* Coefficients Ki for pincushion distortion function which maps
88
+
from position on real screen to virtual screen (i.e. texture) relative
89
+
to optical center:
90
+
91
+
p' = p (1 + K1 r^2 + K2 r^4 + ... + Kn r^(2n))
92
+
93
+
where r is the distance in tan-angle units from the optical center,
94
+
p the input point, and p' the output point. Tan-angle units can be
95
+
computed as distance on the screen divided by distance from the
96
+
virtual eye to the screen. */
97
+
pb_callback_t distortion_coefficients;
98
+
/* Set according to vertical alignment strategy-- see enum comments above.
99
+
NOTE: If you set this to CENTER, see special instructions for the
100
+
tray_to_lens_distance field below. */
101
+
bool has_vertical_alignment;
102
+
cardboard_DeviceParams_VerticalAlignmentType vertical_alignment;
103
+
/* Specify primary input mechanism of the HMD. Intended for advisory
104
+
purposes only, to address simple questions such as "can HMD
105
+
be used with apps requiring a physical button event?" or "what icon
106
+
should be used to represent button action to the user?". */
107
+
bool has_primary_button;
108
+
cardboard_DeviceParams_ButtonType primary_button;
109
+
} cardboard_DeviceParams;
110
+
111
+
112
+
#ifdef __cplusplus
113
+
extern "C" {
114
+
#endif
115
+
116
+
/* Helper constants for enums */
117
+
#define _cardboard_DeviceParams_VerticalAlignmentType_MIN cardboard_DeviceParams_VerticalAlignmentType_BOTTOM
118
+
#define _cardboard_DeviceParams_VerticalAlignmentType_MAX cardboard_DeviceParams_VerticalAlignmentType_TOP
119
+
#define _cardboard_DeviceParams_VerticalAlignmentType_ARRAYSIZE ((cardboard_DeviceParams_VerticalAlignmentType)(cardboard_DeviceParams_VerticalAlignmentType_TOP+1))
120
+
121
+
#define _cardboard_DeviceParams_ButtonType_MIN cardboard_DeviceParams_ButtonType_NONE
122
+
#define _cardboard_DeviceParams_ButtonType_MAX cardboard_DeviceParams_ButtonType_INDIRECT_TOUCH
123
+
#define _cardboard_DeviceParams_ButtonType_ARRAYSIZE ((cardboard_DeviceParams_ButtonType)(cardboard_DeviceParams_ButtonType_INDIRECT_TOUCH+1))
124
+
125
+
#define cardboard_DeviceParams_vertical_alignment_ENUMTYPE cardboard_DeviceParams_VerticalAlignmentType
126
+
#define cardboard_DeviceParams_primary_button_ENUMTYPE cardboard_DeviceParams_ButtonType
127
+
128
+
129
+
/* Initializer values for message structs */
130
+
#define cardboard_DeviceParams_init_default {{{NULL}, NULL}, {{NULL}, NULL}, false, 0, false, 0, {{NULL}, NULL}, false, 0, {{NULL}, NULL}, false, cardboard_DeviceParams_VerticalAlignmentType_BOTTOM, false, cardboard_DeviceParams_ButtonType_MAGNET}
131
+
#define cardboard_DeviceParams_init_zero {{{NULL}, NULL}, {{NULL}, NULL}, false, 0, false, 0, {{NULL}, NULL}, false, 0, {{NULL}, NULL}, false, _cardboard_DeviceParams_VerticalAlignmentType_MIN, false, _cardboard_DeviceParams_ButtonType_MIN}
132
+
133
+
/* Field tags (for use in manual encoding/decoding) */
134
+
#define cardboard_DeviceParams_vendor_tag 1
135
+
#define cardboard_DeviceParams_model_tag 2
136
+
#define cardboard_DeviceParams_screen_to_lens_distance_tag 3
137
+
#define cardboard_DeviceParams_inter_lens_distance_tag 4
138
+
#define cardboard_DeviceParams_left_eye_field_of_view_angles_tag 5
139
+
#define cardboard_DeviceParams_tray_to_lens_distance_tag 6
140
+
#define cardboard_DeviceParams_distortion_coefficients_tag 7
141
+
#define cardboard_DeviceParams_vertical_alignment_tag 11
142
+
#define cardboard_DeviceParams_primary_button_tag 12
143
+
144
+
/* Struct field encoding specification for nanopb */
145
+
#define cardboard_DeviceParams_FIELDLIST(X, a) \
146
+
X(a, CALLBACK, OPTIONAL, STRING, vendor, 1) \
147
+
X(a, CALLBACK, OPTIONAL, STRING, model, 2) \
148
+
X(a, STATIC, OPTIONAL, FLOAT, screen_to_lens_distance, 3) \
149
+
X(a, STATIC, OPTIONAL, FLOAT, inter_lens_distance, 4) \
150
+
X(a, CALLBACK, REPEATED, FLOAT, left_eye_field_of_view_angles, 5) \
151
+
X(a, STATIC, OPTIONAL, FLOAT, tray_to_lens_distance, 6) \
152
+
X(a, CALLBACK, REPEATED, FLOAT, distortion_coefficients, 7) \
153
+
X(a, STATIC, OPTIONAL, UENUM, vertical_alignment, 11) \
154
+
X(a, STATIC, OPTIONAL, UENUM, primary_button, 12)
155
+
#define cardboard_DeviceParams_CALLBACK pb_default_field_callback
156
+
#define cardboard_DeviceParams_DEFAULT (const pb_byte_t*)"\x60\x01\x00"
157
+
158
+
extern const pb_msgdesc_t cardboard_DeviceParams_msg;
159
+
160
+
/* Defines for backwards compatibility with code written before nanopb-0.4.0 */
161
+
#define cardboard_DeviceParams_fields &cardboard_DeviceParams_msg
162
+
163
+
/* Maximum encoded size of messages (where known) */
164
+
/* cardboard_DeviceParams_size depends on runtime parameters */
165
+
166
+
#ifdef __cplusplus
167
+
} /* extern "C" */
168
+
#endif
169
+
170
+
#endif
+123
src/external/cardboard/cardboard_device.proto
+123
src/external/cardboard/cardboard_device.proto
···
···
1
+
/*
2
+
* Copyright 2019 Google LLC
3
+
*
4
+
* Licensed under the Apache License, Version 2.0 (the "License");
5
+
* you may not use this file except in compliance with the License.
6
+
* You may obtain a copy of the License at
7
+
*
8
+
* http://www.apache.org/licenses/LICENSE-2.0
9
+
*
10
+
* Unless required by applicable law or agreed to in writing, software
11
+
* distributed under the License is distributed on an "AS IS" BASIS,
12
+
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13
+
* See the License for the specific language governing permissions and
14
+
* limitations under the License.
15
+
*/
16
+
syntax = "proto2";
17
+
18
+
package cardboard;
19
+
20
+
option java_package = "com.google.cardboard.proto";
21
+
option java_outer_classname = "CardboardDevice";
22
+
option optimize_for = LITE_RUNTIME;
23
+
24
+
/**
25
+
* Message describing properties of a VR head mount device (HMD) which uses an
26
+
* interchangeable smartphone as a display (e.g. Google Cardboard).
27
+
*
28
+
* While some properties are certain (e.g. inter_lens_distance), others
29
+
* represent nominal values which may be refined depending on context (e.g.
30
+
* viewport_angles).
31
+
*
32
+
* Lengths are in meters unless noted otherwise. Fields are _required_
33
+
* unless noted otherwise.
34
+
*
35
+
* Some context on why this set of parameters are deemed necessary and
36
+
* sufficient:
37
+
* * FOV scale can be reasonably approximated from lens-to-screen distance
38
+
* and display size (i.e. knowing lens focal length isn't crucial).
39
+
* * Lenses are assumed to be horizontally centered with respect to
40
+
* display.
41
+
* * The display is not necessarily vertically centered. For interchangeable
42
+
* phones where the device rests against a tray, we can derive
43
+
* the vertical offset from tray-to-lens height along with phone-specific
44
+
* bezel and screen sizes (supplied separately).
45
+
*/
46
+
message DeviceParams {
47
+
// String identifying the device's vendor (e.g. "Google, Inc.").
48
+
// A device's [vendor, model] pair is expected to be globally unique.
49
+
optional string vendor = 1;
50
+
51
+
// String identifying the device's model, including revision info if
52
+
// needed (e.g. "Cardboard v1"). A device's [vendor, model] pair is
53
+
// expected to be globally unique.
54
+
optional string model = 2;
55
+
56
+
// Distance from the display screen to the optical center of lenses.
57
+
// This is a required field for distortion rendering, and must be positive.
58
+
optional float screen_to_lens_distance = 3;
59
+
60
+
// Horizontal distance between optical center of the lenses.
61
+
// This is a required field for distortion rendering, and must be positive.
62
+
optional float inter_lens_distance = 4;
63
+
64
+
// Four-element tuple (left, right, bottom, top) of left eye's view extent
65
+
// angles relative to center, assuming the following:
66
+
// * eye is aligned with optical center of lens
67
+
// * display screen is equal or larger than extents viewable through lens
68
+
// * nominal eye-to-lens distance
69
+
// * mirrored field of view will be applied to the right eye
70
+
// These values are essentially used as an optimization to avoid rendering
71
+
// pixels which can't be seen.
72
+
// This is a required field for distortion rendering, and angles must be
73
+
// positive.
74
+
repeated float left_eye_field_of_view_angles = 5 [packed = true];
75
+
76
+
enum VerticalAlignmentType {
77
+
BOTTOM = 0; // phone rests against a fixed bottom tray
78
+
CENTER = 1; // phone screen assumed to be centered w.r.t. lenses
79
+
TOP = 2; // phone rests against a fixed top tray
80
+
}
81
+
82
+
// Set according to vertical alignment strategy-- see enum comments above.
83
+
// NOTE: If you set this to CENTER, see special instructions for the
84
+
// tray_to_lens_distance field below.
85
+
optional VerticalAlignmentType vertical_alignment = 11 [default = BOTTOM];
86
+
87
+
// If the phone is aligned vertically within the device by resting against
88
+
// a fixed top or bottom tray, this is the distance from the tray to
89
+
// optical center of the lenses.
90
+
// This is a required field for distortion rendering, and must be positive.
91
+
// NOTE: Due to a bug in initial versions of the SDK's, this field
92
+
// must be set explicitly to .035 when vertical_alignment = CENTER.
93
+
optional float tray_to_lens_distance = 6;
94
+
95
+
// Coefficients Ki for pincushion distortion function which maps
96
+
// from position on real screen to virtual screen (i.e. texture) relative
97
+
// to optical center:
98
+
//
99
+
// p' = p (1 + K1 r^2 + K2 r^4 + ... + Kn r^(2n))
100
+
//
101
+
// where r is the distance in tan-angle units from the optical center,
102
+
// p the input point, and p' the output point. Tan-angle units can be
103
+
// computed as distance on the screen divided by distance from the
104
+
// virtual eye to the screen.
105
+
repeated float distortion_coefficients = 7 [packed = true];
106
+
107
+
enum ButtonType {
108
+
// No physical button, and touch screen is not easily accessible.
109
+
NONE = 0;
110
+
// HMD has integrated magnet switch similar to original Cardboard.
111
+
MAGNET = 1;
112
+
// At least a portion of touch screen is easily accessible to user for taps.
113
+
TOUCH = 2;
114
+
// Touch screen is triggered indirectly via integrated button on the HMD.
115
+
INDIRECT_TOUCH = 3;
116
+
}
117
+
118
+
// Specify primary input mechanism of the HMD. Intended for advisory
119
+
// purposes only, to address simple questions such as "can HMD
120
+
// be used with apps requiring a physical button event?" or "what icon
121
+
// should be used to represent button action to the user?".
122
+
optional ButtonType primary_button = 12 [default = MAGNET];
123
+
}
+2
-1
src/xrt/drivers/CMakeLists.txt
+2
-1
src/xrt/drivers/CMakeLists.txt
+129
-14
src/xrt/drivers/android/android_sensors.c
+129
-14
src/xrt/drivers/android/android_sensors.c
···
1
// Copyright 2013, Fredrik Hultin.
2
// Copyright 2013, Jakob Bornecrantz.
3
// Copyright 2015, Joey Ferwerda.
4
-
// Copyright 2020-2023, Collabora, Ltd.
5
// SPDX-License-Identifier: BSL-1.0
6
/*!
7
* @file
8
* @brief Android sensors driver code.
9
* @author Lubosz Sarnecki <lubosz.sarnecki@collabora.com>
10
* @ingroup drv_android
11
*/
12
···
18
#include "util/u_var.h"
19
#include "util/u_visibility_mask.h"
20
21
#include "android/android_globals.h"
22
#include "android/android_custom_surface.h"
23
24
#include <xrt/xrt_config_android.h>
···
40
return (struct android_device *)xdev;
41
}
42
43
// Callback for the Android sensor event queue
44
static int
45
android_sensor_callback(ASensorEvent *event, struct android_device *d)
···
251
d->base.name = XRT_DEVICE_GENERIC_HMD;
252
d->base.destroy = android_device_destroy;
253
d->base.update_inputs = u_device_noop_update_inputs;
254
d->base.get_tracked_pose = android_device_get_tracked_pose;
255
d->base.get_view_poses = u_device_get_view_poses;
256
d->base.get_visibility_mask = u_device_get_visibility_mask;
···
284
285
d->base.hmd->screens[0].nominal_frame_interval_ns = time_s_to_ns(1.0f / metrics.refresh_rate);
286
287
-
// Everything done, finally start the thread.
288
-
os_thread_helper_init(&d->oth);
289
-
ret = os_thread_helper_start(&d->oth, android_run_thread, d);
290
-
if (ret != 0) {
291
-
ANDROID_ERROR(d, "Failed to start thread!");
292
-
android_device_destroy(&d->base);
293
-
return NULL;
294
-
}
295
-
296
const uint32_t w_pixels = metrics.width_pixels;
297
const uint32_t h_pixels = metrics.height_pixels;
298
···
300
const float w_meters = ((float)w_pixels / (float)metrics.xdpi) * 0.0254f;
301
const float h_meters = ((float)h_pixels / (float)metrics.ydpi) * 0.0254f;
302
303
-
struct u_cardboard_distortion_arguments args = {
304
.distortion_k = {0.441f, 0.156f, 0.f, 0.f, 0.f},
305
.screen =
306
{
···
320
.angle_down = -angle,
321
},
322
};
323
324
u_distortion_cardboard_calculate(&args, d->base.hmd, &d->cardboard);
325
326
327
u_var_add_root(d, "Android phone", true);
328
u_var_add_ro_vec3_f32(d, &d->fusion.last.accel, "last.accel");
329
u_var_add_ro_vec3_f32(d, &d->fusion.last.gyro, "last.gyro");
330
331
d->base.supported.orientation_tracking = true;
332
d->base.supported.position_tracking = false;
333
-
334
-
// Distortion information.
335
-
u_distortion_mesh_fill_in_compute(&d->base);
336
337
ANDROID_DEBUG(d, "Created device!");
338
···
1
// Copyright 2013, Fredrik Hultin.
2
// Copyright 2013, Jakob Bornecrantz.
3
// Copyright 2015, Joey Ferwerda.
4
+
// Copyright 2020-2025, Collabora, Ltd.
5
// SPDX-License-Identifier: BSL-1.0
6
/*!
7
* @file
8
* @brief Android sensors driver code.
9
* @author Lubosz Sarnecki <lubosz.sarnecki@collabora.com>
10
+
* @author Korcan Hussein <korcan.hussein@collabora.com>
11
+
* @author Simon Zeni <simon.zeni@collabora.com>
12
* @ingroup drv_android
13
*/
14
···
20
#include "util/u_var.h"
21
#include "util/u_visibility_mask.h"
22
23
+
#include "cardboard_device.pb.h"
24
+
#include "pb_decode.h"
25
+
26
#include "android/android_globals.h"
27
+
#include "android/android_content.h"
28
#include "android/android_custom_surface.h"
29
30
#include <xrt/xrt_config_android.h>
···
46
return (struct android_device *)xdev;
47
}
48
49
+
static bool
50
+
read_file(pb_istream_t *stream, uint8_t *buf, size_t count)
51
+
{
52
+
U_LOG_E("read_file callback");
53
+
FILE *file = (FILE *)stream->state;
54
+
if (buf == NULL) {
55
+
while (count-- && fgetc(file) != EOF)
56
+
;
57
+
return count == 0;
58
+
}
59
+
60
+
bool status = (fread(buf, 1, count, file) == count);
61
+
62
+
if (feof(file)) {
63
+
stream->bytes_left = 0;
64
+
}
65
+
66
+
return status;
67
+
}
68
+
69
+
static bool
70
+
read_buffer(pb_istream_t *stream, const pb_field_t *field, void **arg)
71
+
{
72
+
U_LOG_E("read_file callback");
73
+
uint8_t *buffer = (uint8_t *)*arg;
74
+
return pb_read(stream, buffer, stream->bytes_left);
75
+
}
76
+
77
+
static bool
78
+
load_cardboard_distortion(struct android_device *d,
79
+
struct xrt_android_display_metrics *metrics,
80
+
struct u_cardboard_distortion_arguments *args)
81
+
{
82
+
char external_storage_dir[PATH_MAX] = {0};
83
+
if (!android_content_get_files_dir(android_globals_get_context(), external_storage_dir,
84
+
sizeof(external_storage_dir))) {
85
+
ANDROID_ERROR(d, "failed to access files dir");
86
+
return false;
87
+
}
88
+
89
+
/* TODO: put file in Cardboard folder */
90
+
char device_params_file[PATH_MAX] = {0};
91
+
snprintf(device_params_file, sizeof(device_params_file), "%s/current_device_params", external_storage_dir);
92
+
93
+
FILE *file = fopen(device_params_file, "rb");
94
+
if (file == NULL) {
95
+
ANDROID_ERROR(d, "failed to open calibration file '%s'", device_params_file);
96
+
return false;
97
+
}
98
+
99
+
pb_istream_t stream = {&read_file, file, SIZE_MAX, NULL};
100
+
cardboard_DeviceParams params = cardboard_DeviceParams_init_zero;
101
+
102
+
char vendor[64] = {0};
103
+
params.vendor.arg = vendor;
104
+
params.vendor.funcs.decode = read_buffer;
105
+
106
+
char model[64] = {0};
107
+
params.model.arg = model;
108
+
params.model.funcs.decode = read_buffer;
109
+
110
+
float angles[4] = {0};
111
+
params.left_eye_field_of_view_angles.arg = angles;
112
+
params.left_eye_field_of_view_angles.funcs.decode = read_buffer;
113
+
114
+
params.distortion_coefficients.arg = args->distortion_k;
115
+
params.distortion_coefficients.funcs.decode = read_buffer;
116
+
117
+
if (!pb_decode(&stream, cardboard_DeviceParams_fields, ¶ms)) {
118
+
ANDROID_ERROR(d, "failed to read calibration file: %s", PB_GET_ERROR(&stream));
119
+
return false;
120
+
}
121
+
122
+
if (params.has_vertical_alignment) {
123
+
if (params.vertical_alignment != cardboard_DeviceParams_VerticalAlignmentType_BOTTOM) {
124
+
ANDROID_ERROR(d, "Only vertical alignment bottom supported");
125
+
return false;
126
+
}
127
+
}
128
+
129
+
if (params.has_inter_lens_distance) {
130
+
args->inter_lens_distance_meters = params.inter_lens_distance;
131
+
}
132
+
if (params.has_screen_to_lens_distance) {
133
+
args->screen_to_lens_distance_meters = params.screen_to_lens_distance;
134
+
}
135
+
if (params.has_tray_to_lens_distance) {
136
+
args->tray_to_lens_distance_meters = params.tray_to_lens_distance;
137
+
}
138
+
139
+
#define DEG_TO_RAD(x) (float)(x * M_PI / 180.0)
140
+
args->fov = (struct xrt_fov){.angle_left = -DEG_TO_RAD(angles[0]),
141
+
.angle_right = DEG_TO_RAD(angles[1]),
142
+
.angle_down = -DEG_TO_RAD(angles[2]),
143
+
.angle_up = DEG_TO_RAD(angles[3])};
144
+
#undef DEG_TO_RAD
145
+
146
+
ANDROID_INFO(d, "loaded calibration for device %s (%s)", model, vendor);
147
+
148
+
return true;
149
+
}
150
+
151
// Callback for the Android sensor event queue
152
static int
153
android_sensor_callback(ASensorEvent *event, struct android_device *d)
···
359
d->base.name = XRT_DEVICE_GENERIC_HMD;
360
d->base.destroy = android_device_destroy;
361
d->base.update_inputs = u_device_noop_update_inputs;
362
+
d->base.set_output = u_device_ni_set_output;
363
d->base.get_tracked_pose = android_device_get_tracked_pose;
364
d->base.get_view_poses = u_device_get_view_poses;
365
d->base.get_visibility_mask = u_device_get_visibility_mask;
···
393
394
d->base.hmd->screens[0].nominal_frame_interval_ns = time_s_to_ns(1.0f / metrics.refresh_rate);
395
396
const uint32_t w_pixels = metrics.width_pixels;
397
const uint32_t h_pixels = metrics.height_pixels;
398
···
400
const float w_meters = ((float)w_pixels / (float)metrics.xdpi) * 0.0254f;
401
const float h_meters = ((float)h_pixels / (float)metrics.ydpi) * 0.0254f;
402
403
+
const struct u_cardboard_distortion_arguments cardboard_v1_distortion_args = {
404
.distortion_k = {0.441f, 0.156f, 0.f, 0.f, 0.f},
405
.screen =
406
{
···
420
.angle_down = -angle,
421
},
422
};
423
+
struct u_cardboard_distortion_arguments args = cardboard_v1_distortion_args;
424
+
if (!load_cardboard_distortion(d, &metrics, &args)) {
425
+
ANDROID_WARN(
426
+
d, "Failed to load cardboard calibration file, falling back to Cardboard V1 distortion values");
427
+
args = cardboard_v1_distortion_args;
428
+
}
429
430
u_distortion_cardboard_calculate(&args, d->base.hmd, &d->cardboard);
431
432
+
// Distortion information.
433
+
u_distortion_mesh_fill_in_compute(&d->base);
434
+
435
+
// Everything done, finally start the thread.
436
+
os_thread_helper_init(&d->oth);
437
+
ret = os_thread_helper_start(&d->oth, android_run_thread, d);
438
+
if (ret != 0) {
439
+
ANDROID_ERROR(d, "Failed to start thread!");
440
+
android_device_destroy(&d->base);
441
+
return NULL;
442
+
}
443
444
u_var_add_root(d, "Android phone", true);
445
+
u_var_add_log_level(d, &d->log_level, "log_level");
446
u_var_add_ro_vec3_f32(d, &d->fusion.last.accel, "last.accel");
447
u_var_add_ro_vec3_f32(d, &d->fusion.last.gyro, "last.gyro");
448
449
d->base.supported.orientation_tracking = true;
450
d->base.supported.position_tracking = false;
451
452
ANDROID_DEBUG(d, "Created device!");
453