Move radian and degree conversion constants to generic_sensor_consts.h

Currently there are radian and degree conversion constants in both
generic_sensor_consts.h and orientation_util.h. This CL moves them to
generic_sensor_consts.h.

Bug: None
Change-Id: I7de69b7e9536bb003158ab9d3611ec9a621211fc
Reviewed-on: https://chromium-review.googlesource.com/661077
Commit-Queue: Jun Cai <juncai@chromium.org>
Reviewed-by: Reilly Grant <reillyg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#501311}

services/device/generic_sensor/absolute_orientation_euler_angles_fusion_algorithm_using_accelerometer_and_magnetometer_unittest.cc

@@ -9,7 +9,7 @@
 #include "services/device/device_service_test_base.h"
 #include "services/device/generic_sensor/absolute_orientation_euler_angles_fusion_algorithm_using_accelerometer_and_magnetometer.h"
 #include "services/device/generic_sensor/fake_platform_sensor_fusion.h"
-#include "services/device/generic_sensor/orientation_util.h"
+#include "services/device/generic_sensor/generic_sensor_consts.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace device {
@@ -191,8 +191,8 @@ TEST_F(
     AbsoluteOrientationEulerAnglesFusionAlgorithmUsingAccelerometerAndMagnetometerTest,
     BetaIs45Degrees) {
   double gravity_x = 0.0;
-  double gravity_y = std::sin(kDegToRad * 45.0);
-  double gravity_z = std::cos(kDegToRad * 45.0);
+  double gravity_y = std::sin(kDegreesToRadians * 45.0);
+  double gravity_z = std::cos(kDegreesToRadians * 45.0);
   double geomagnetic_x = 0.0;
   double geomagnetic_y = 1.0;
   double geomagnetic_z = 0.0;
@@ -210,9 +210,9 @@ TEST_F(
 TEST_F(
     AbsoluteOrientationEulerAnglesFusionAlgorithmUsingAccelerometerAndMagnetometerTest,
     GammaIs45Degrees) {
-  double gravity_x = -std::sin(kDegToRad * 45.0);
+  double gravity_x = -std::sin(kDegreesToRadians * 45.0);
   double gravity_y = 0.0;
-  double gravity_z = std::cos(kDegToRad * 45.0);
+  double gravity_z = std::cos(kDegreesToRadians * 45.0);
   double geomagnetic_x = 0.0;
   double geomagnetic_y = 1.0;
   double geomagnetic_z = 0.0;
@@ -233,8 +233,8 @@ TEST_F(
   double gravity_x = 0.0;
   double gravity_y = 0.0;
   double gravity_z = 1.0;
-  double geomagnetic_x = std::sin(kDegToRad * 45.0);
-  double geomagnetic_y = std::cos(kDegToRad * 45.0);
+  double geomagnetic_x = std::sin(kDegreesToRadians * 45.0);
+  double geomagnetic_y = std::cos(kDegreesToRadians * 45.0);
   double geomagnetic_z = 0.0;
 
   double expected_alpha_in_degrees = 45.0;
@@ -253,9 +253,9 @@ TEST_F(
   double gravity_x = 0.0;
   double gravity_y = 1.0;
   double gravity_z = 0.0;
-  double geomagnetic_x = std::sin(kDegToRad * 45.0);
+  double geomagnetic_x = std::sin(kDegreesToRadians * 45.0);
   double geomagnetic_y = 0.0;
-  double geomagnetic_z = -std::cos(kDegToRad * 45.0);
+  double geomagnetic_z = -std::cos(kDegreesToRadians * 45.0);
 
   // Favor Alpha instead of Gamma.
   double expected_alpha_in_degrees = 45.0;
@@ -272,8 +272,8 @@ TEST_F(
     AbsoluteOrientationEulerAnglesFusionAlgorithmUsingAccelerometerAndMagnetometerTest,
     BetaIsGreaterThan90Degrees) {
   double gravity_x = 0.0;
-  double gravity_y = std::cos(kDegToRad * 45.0);
-  double gravity_z = -std::sin(kDegToRad * 45.0);
+  double gravity_y = std::cos(kDegreesToRadians * 45.0);
+  double gravity_z = -std::sin(kDegreesToRadians * 45.0);
   double geomagnetic_x = 0.0;
   double geomagnetic_y = 0.0;
   double geomagnetic_z = -1.0;

services/device/generic_sensor/generic_sensor_consts.h

@@ -6,6 +6,7 @@
 #define SERVICES_DEVICE_GENERIC_SENSOR_GENERIC_SENSOR_CONSTS_H_
 
 #define _USE_MATH_DEFINES
+
 #include <math.h>
 
 namespace device {
@@ -13,8 +14,11 @@ namespace device {
 // Required for conversion from G/s^2 to m/s^2
 constexpr double kMeanGravity = 9.80665;
 
-// Required for conversion from deg to rad
-constexpr double kRadiansInDegrees = M_PI / 180.0;
+// Conversion ratio from radians to degrees.
+constexpr double kRadiansToDegrees = 180.0 / M_PI;
+
+// Conversion ratio from degrees to radians.
+constexpr double kDegreesToRadians = M_PI / 180.0;
 
 // Required for conversion from Gauss to uT.
 constexpr double kMicroteslaInGauss = 100.0;

services/device/generic_sensor/linux/sensor_data_linux.cc

@@ -115,7 +115,7 @@ void InitGyroscopeSensorData(SensorPathsLinux* data) {
   data->sensor_frequency_file_name = "in_anglvel_base_frequency";
   data->apply_scaling_func = base::Bind(
       [](double scaling_value, double offset, SensorReading& reading) {
-        double scaling = kMeanGravity * kRadiansInDegrees / scaling_value;
+        double scaling = kMeanGravity * kDegreesToRadians / scaling_value;
         // Adapt CrOS reading values to generic sensor api specs.
         reading.gyro.x = -scaling * (reading.gyro.x + offset);
         reading.gyro.y = -scaling * (reading.gyro.y + offset);

services/device/generic_sensor/orientation_quaternion_fusion_algorithm_using_euler_angles.cc

@@ -7,7 +7,7 @@
 #include <cmath>
 
 #include "base/logging.h"
-#include "services/device/generic_sensor/orientation_util.h"
+#include "services/device/generic_sensor/generic_sensor_consts.h"
 #include "services/device/generic_sensor/platform_sensor_fusion.h"
 
 namespace device {
@@ -21,9 +21,9 @@ void ComputeQuaternionFromEulerAngles(double alpha_in_degrees,
                                       double* y,
                                       double* z,
                                       double* w) {
-  double alpha_in_radians = device::kDegToRad * alpha_in_degrees;
-  double beta_in_radians = device::kDegToRad * beta_in_degrees;
-  double gamma_in_radians = device::kDegToRad * gamma_in_degrees;
+  double alpha_in_radians = device::kDegreesToRadians * alpha_in_degrees;
+  double beta_in_radians = device::kDegreesToRadians * beta_in_degrees;
+  double gamma_in_radians = device::kDegreesToRadians * gamma_in_degrees;
 
   double cx = std::cos(beta_in_radians / 2);
   double cy = std::cos(gamma_in_radians / 2);

services/device/generic_sensor/orientation_util.cc

@@ -2,13 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#define _USE_MATH_DEFINES  // For VC++ to get M_PI. This has to be first.
-
 #include "services/device/generic_sensor/orientation_util.h"
 
 #include <cmath>
 
 #include "base/logging.h"
+#include "services/device/generic_sensor/generic_sensor_consts.h"
 
 namespace {
 
@@ -94,10 +93,6 @@ void ComputeOrientationEulerAnglesInRadiansFromRotationMatrix(
 
 namespace device {
 
-const double kRadToDeg = 180.0 / M_PI;
-
-const double kDegToRad = M_PI / 180.0;
-
 void ComputeOrientationEulerAnglesFromRotationMatrix(
     const std::vector<double>& r,
     double* alpha_in_degrees,
@@ -106,9 +101,9 @@ void ComputeOrientationEulerAnglesFromRotationMatrix(
   double alpha_in_radians, beta_in_radians, gamma_in_radians;
   ComputeOrientationEulerAnglesInRadiansFromRotationMatrix(
       r, &alpha_in_radians, &beta_in_radians, &gamma_in_radians);
-  *alpha_in_degrees = kRadToDeg * alpha_in_radians;
-  *beta_in_degrees = kRadToDeg * beta_in_radians;
-  *gamma_in_degrees = kRadToDeg * gamma_in_radians;
+  *alpha_in_degrees = kRadiansToDegrees * alpha_in_radians;
+  *beta_in_degrees = kRadiansToDegrees * beta_in_radians;
+  *gamma_in_degrees = kRadiansToDegrees * gamma_in_radians;
 }
 
 }  // namespace device

services/device/generic_sensor/orientation_util.h

@@ -9,12 +9,6 @@
 
 namespace device {
 
-// Conversion ratio from radians to degrees.
-extern const double kRadToDeg;
-
-// Conversion ratio from degrees to radians.
-extern const double kDegToRad;
-
 void ComputeOrientationEulerAnglesFromRotationMatrix(
     const std::vector<double>& r,
     double* alpha_in_degrees,

services/device/generic_sensor/platform_sensor_and_provider_unittest_linux.cc

@@ -638,7 +638,7 @@ TEST_F(PlatformSensorAndProviderLinuxTest, CheckGyroscopeReadingConversion) {
   SensorReadingSharedBuffer* buffer =
       static_cast<SensorReadingSharedBuffer*>(mapping.get());
 #if defined(OS_CHROMEOS)
-  double scaling = kMeanGravity * kRadiansInDegrees / kGyroscopeScalingValue;
+  double scaling = kMeanGravity * kDegreesToRadians / kGyroscopeScalingValue;
   EXPECT_THAT(buffer->reading.gyro.x, -scaling * sensor_values[0]);
   EXPECT_THAT(buffer->reading.gyro.y, -scaling * sensor_values[1]);
   EXPECT_THAT(buffer->reading.gyro.z, -scaling * sensor_values[2]);

services/device/generic_sensor/platform_sensor_and_provider_unittest_win.cc

@@ -625,9 +625,9 @@ TEST_F(PlatformSensorAndProviderTestWin, CheckGyroscopeReadingConversion) {
   base::RunLoop().RunUntilIdle();
   SensorReadingSharedBuffer* buffer =
       static_cast<SensorReadingSharedBuffer*>(mapping.get());
-  EXPECT_THAT(buffer->reading.gyro.x, -x_ang_accel * kRadiansInDegrees);
-  EXPECT_THAT(buffer->reading.gyro.y, -y_ang_accel * kRadiansInDegrees);
-  EXPECT_THAT(buffer->reading.gyro.z, -z_ang_accel * kRadiansInDegrees);
+  EXPECT_THAT(buffer->reading.gyro.x, -x_ang_accel * kDegreesToRadians);
+  EXPECT_THAT(buffer->reading.gyro.y, -y_ang_accel * kDegreesToRadians);
+  EXPECT_THAT(buffer->reading.gyro.z, -z_ang_accel * kDegreesToRadians);
   EXPECT_TRUE(sensor->StopListening(client.get(), configuration));
 }
 

services/device/generic_sensor/platform_sensor_reader_win.cc

@@ -124,9 +124,9 @@ std::unique_ptr<ReaderInitParams> CreateGyroscopeReaderInitParams() {
         // Windows uses coordinate system where Z axis points down from device
         // screen, therefore, using right hand notation, we have to reverse
         // sign for each axis. Values are converted from deg to rad.
-        reading->gyro.x = -x * kRadiansInDegrees;
-        reading->gyro.y = -y * kRadiansInDegrees;
-        reading->gyro.z = -z * kRadiansInDegrees;
+        reading->gyro.x = -x * kDegreesToRadians;
+        reading->gyro.y = -y * kDegreesToRadians;
+        reading->gyro.z = -z * kDegreesToRadians;
         return S_OK;
       };
   return params;

services/device/generic_sensor/relative_orientation_euler_angles_fusion_algorithm_using_accelerometer.cc

@@ -8,7 +8,6 @@
 
 #include "base/logging.h"
 #include "services/device/generic_sensor/generic_sensor_consts.h"
-#include "services/device/generic_sensor/orientation_util.h"
 #include "services/device/generic_sensor/platform_sensor_fusion.h"
 
 namespace device {
@@ -41,8 +40,10 @@ void ComputeRelativeOrientationFromAccelerometer(double acceleration_x,
   // This is necessary in order to provide enough information to solve
   // the equations.
   *alpha_in_degrees = 0.0;
-  *beta_in_degrees = kRadToDeg * std::atan2(-acceleration_y, acceleration_z);
-  *gamma_in_degrees = kRadToDeg * std::asin(acceleration_x / kMeanGravity);
+  *beta_in_degrees =
+      kRadiansToDegrees * std::atan2(-acceleration_y, acceleration_z);
+  *gamma_in_degrees =
+      kRadiansToDegrees * std::asin(acceleration_x / kMeanGravity);
 
   // Convert beta and gamma to fit the intervals in the specification. Beta is
   // [-180, 180) and gamma is [-90, 90).