void MotionEvent::transform(const SkMatrix* matrix) {
float oldXOffset = mXOffset;
float oldYOffset = mYOffset;
// The tricky part of this implementation is to preserve the value of
// rawX and rawY. So we apply the transformation to the first point
// then derive an appropriate new X/Y offset that will preserve rawX and rawY.
SkPoint point;
float rawX = getRawX(0);
float rawY = getRawY(0);
matrix->mapXY(SkFloatToScalar(rawX + oldXOffset), SkFloatToScalar(rawY + oldYOffset),
& point);
float newX = SkScalarToFloat(point.fX);
float newY = SkScalarToFloat(point.fY);
float newXOffset = newX - rawX;
float newYOffset = newY - rawY;
mXOffset = newXOffset;
mYOffset = newYOffset;
// Apply the transformation to all samples.
size_t numSamples = mSamplePointerCoords.size();
for (size_t i = 0; i < numSamples; i++) {
PointerCoords& c = mSamplePointerCoords.editItemAt(i);
float x = c.getAxisValue(AMOTION_EVENT_AXIS_X) + oldXOffset;
float y = c.getAxisValue(AMOTION_EVENT_AXIS_Y) + oldYOffset;
matrix->mapXY(SkFloatToScalar(x), SkFloatToScalar(y), &point);
c.setAxisValue(AMOTION_EVENT_AXIS_X, SkScalarToFloat(point.fX) - newXOffset);
c.setAxisValue(AMOTION_EVENT_AXIS_Y, SkScalarToFloat(point.fY) - newYOffset);
float orientation = c.getAxisValue(AMOTION_EVENT_AXIS_ORIENTATION);
c.setAxisValue(AMOTION_EVENT_AXIS_ORIENTATION, transformAngle(matrix, orientation));
}
}
void MotionEvent::transform(const float matrix[9]) {
// The tricky part of this implementation is to preserve the value of
// rawX and rawY. So we apply the transformation to the first point
// then derive an appropriate new X/Y offset that will preserve rawX
// and rawY for that point.
float oldXOffset = mXOffset;
float oldYOffset = mYOffset;
float newX, newY;
float rawX = getRawX(0);
float rawY = getRawY(0);
transformPoint(matrix, rawX + oldXOffset, rawY + oldYOffset, &newX, &newY);
mXOffset = newX - rawX;
mYOffset = newY - rawY;
// Determine how the origin is transformed by the matrix so that we
// can transform orientation vectors.
float originX, originY;
transformPoint(matrix, 0, 0, &originX, &originY);
// Apply the transformation to all samples.
size_t numSamples = mSamplePointerCoords.size();
for (size_t i = 0; i < numSamples; i++) {
PointerCoords& c = mSamplePointerCoords.editItemAt(i);
float x = c.getAxisValue(AMOTION_EVENT_AXIS_X) + oldXOffset;
float y = c.getAxisValue(AMOTION_EVENT_AXIS_Y) + oldYOffset;
transformPoint(matrix, x, y, &x, &y);
c.setAxisValue(AMOTION_EVENT_AXIS_X, x - mXOffset);
c.setAxisValue(AMOTION_EVENT_AXIS_Y, y - mYOffset);
float orientation = c.getAxisValue(AMOTION_EVENT_AXIS_ORIENTATION);
c.setAxisValue(AMOTION_EVENT_AXIS_ORIENTATION,
transformAngle(matrix, orientation, originX, originY));
}
}
