Change images to use ImageMask instances instead of Depth1Image instances as
masks.
#define b_moveDown_width 16
#define b_moveDown_height 16
static unsigned char b_moveDown_bits[] = {
0x00, 0x00, 0xf0, 0x07, 0xe0, 0x03, 0xc0, 0x01, 0x80, 0x00, 0x00, 0x00,
0xf0, 0x07, 0xe0, 0x03, 0xc0, 0x01, 0x80, 0x00, 0x00, 0x00, 0xf0, 0x07,
0xe0, 0x03, 0xc0, 0x01, 0x80, 0x00, 0x00, 0x00};