32 lines
747 B
Text
32 lines
747 B
Text
-- Lesson 4: Doing It Again
|
|
|
|
LAYERS = 3
|
|
STARS_PER_LAYER = 40
|
|
ACROSS_STEP = 37
|
|
DOWN_STEP = 61
|
|
LAYER_SHIFT = 13
|
|
LAYER_SPEED = 0.5
|
|
LAYER_BRIGHT = 55
|
|
|
|
width = overlayGetWidth()
|
|
height = overlayGetHeight()
|
|
|
|
drift = 0
|
|
|
|
|
|
function onOverlayUpdate()
|
|
drift = drift + 1
|
|
overlayClear()
|
|
|
|
for layer = 1, LAYERS do
|
|
for star = 1, STARS_PER_LAYER do
|
|
starX = (star * ACROSS_STEP + layer * LAYER_SHIFT) % width
|
|
starY = (star * DOWN_STEP + math.floor(drift * layer * LAYER_SPEED)) % height
|
|
shade = math.random(60, 90) + layer * LAYER_BRIGHT
|
|
colorForeground(shade, shade, shade)
|
|
overlayPlot(starX, starY)
|
|
end
|
|
end
|
|
|
|
return OVERLAY_UPDATED
|
|
end
|