// Handles motion (dx, dy) in screen space.
// The "edge" parameter specifies which edges the user is dragging.
void handleMotion(int edge, float dx, float dy) {
Rect r = computeLayout();
if (edge == GROW_NONE) {
return;
} else if (edge == MOVE) {
// Convert to image space before sending to moveBy().
moveBy(dx * (mCropRect.width() / r.width()), dy * (mCropRect.height() / r.height()));
} else {
if (((GROW_LEFT_EDGE | GROW_RIGHT_EDGE) & edge) == 0) {
dx = 0;
}
if (((GROW_TOP_EDGE | GROW_BOTTOM_EDGE) & edge) == 0) {
dy = 0;
}
// Convert to image space before sending to growBy().
float xDelta = dx * (mCropRect.width() / r.width());
float yDelta = dy * (mCropRect.height() / r.height());
growBy(
(((edge & GROW_LEFT_EDGE) != 0) ? -1 : 1) * xDelta,
(((edge & GROW_TOP_EDGE) != 0) ? -1 : 1) * yDelta);
}
}
