//A procedure that moves a <sprite> to
//  <position y> (Y) and <position x> (X).
.macro moveSprite(sprite) {
    .const xReg = [VIC.SPRITE_0_X + [sprite * 2]]
    .const yReg = [xReg + 1]
    lda VIC.SPRITE_X_MSB
    bcs setMSB
    and #[[1 << sprite] ^ $ff]
    bcc store
    setMSB:
    ora #[1 << sprite]
    store:
    sta VIC.SPRITE_X_MSB
    stx xReg
    sty yReg
}