STPK-1429 Fix coordinate system mapping for gyro and magn

It turns out they are consistent. Android uses a different
coordinate system, with axes based on the "natural orientation"
of the device, but the transfom is the same for these three
sensors as they are using the same convention.

Issue: STPK-1429

Change-Id: I5e9b819a30422ca8134c39e427c21178cdef68a0
Signed-off-by: Patrick Porlan <patrick.porlan@intel.com>

diff --git a/transform.c b/transform.c
index b91642c..4ead4e3 100644 (file)
--- a/transform.c
+++ b/transform.c
@@ -173,6 +173,7 @@ static void finalize_sample_default(int s, struct sensors_event_t* data)
 {
        int i           = sensor_info[s].catalog_index;
        int sensor_type = sensor_catalog[i].type;
+       float x, y, z;
 
        switch (sensor_type) {
                case SENSOR_TYPE_ACCELEROMETER:
@@ -181,19 +182,37 @@ static void finalize_sample_default(int s, struct sensors_event_t* data)
                         * /hardware/libhardware/include/hardware/sensors.h
                         * for a discussion of what Android expects
                         */
-                       data->data[0] = -data->data[0];
-                       data->data[2] = -data->data[2];
+                       x = -data->data[0];
+                       y = data->data[1];
+                       z = -data->data[2];
+
+                       data->data[0] = x;
+                       data->data[1] = y;
+                       data->data[2] = z;
+                       break;
+
+               case SENSOR_TYPE_MAGNETIC_FIELD:
+                       x = -data->data[0];
+                       y = data->data[1];
+                       z = -data->data[2];
+
+                       data->data[0] = x;
+                       data->data[1] = y;
+                       data->data[2] = z;
                        break;
 
                case SENSOR_TYPE_GYROSCOPE:
+                       x = -data->data[0];
+                       y = data->data[1];
+                       z = -data->data[2];
+
                        /* Limit drift */
-                       if (    fabs(data->data[0]) < 0.1 &&
-                               fabs(data->data[1]) < 0.1 &&
-                               fabs(data->data[2]) < 0.1) {
-                                       data->data[0] = 0;
-                                       data->data[1] = 0;
-                                       data->data[2] = 0;
-                               }
+                       if (fabs(x) < 0.1 && fabs(y) < 0.1 && fabs(z) < 0.1)
+                               x = y = z = 0;
+
+                       data->data[0] = x;
+                       data->data[1] = y;
+                       data->data[2] = z;
                        break;
 
                case SENSOR_TYPE_AMBIENT_TEMPERATURE: