spring_dy = (spring_y - spring_y_target) * SPRING_CONSTANT 
spring_dy *= (1-DAMPING_CONSTANT)
spring_y += spring_dy

 y= 10 -- The vertical position in PIXELS
 h= 3 -- The height in rows of EIGHT pixels
 poke(0x5f5f,0x10) -- enable the effect
 pal(NEW_PAL,2) -- Set the pallete for the section
 pal_memset(0x5f70,0,16) -- clear the settings from previous update
 local rem=flr(y)%8 -- calculate the remainder, since the dual-pallete mode works rows of 8 at a pixels at a time
 pal_memset(0x5f70+(y)/8-1,255<<rem,1) -- Set the flags above where main body made of full 8-high rows can be set
 pal_memset(0x5f70+(y)/8,255,h) --Set the flags for the main body of h 8-pixel-high rows
 pal_memset(0x5f70+(y)/8+h,~(255<<rem),1) -- Set the flags below where main body made of full 8-high rows can be set

function pal_memset(addr, val, len)
    if addr >= min_mem and (addr + len - 1) <= max_mem then
        memset(addr, val, len)
    end
end