Files
matrix/playdate/matrix_lua/Source/main.lua

132 lines
3.7 KiB
Lua

local gfx <const> = playdate.graphics
local floor <const> = math.floor
local random <const> = math.random
local screenWidth <const> = playdate.display.getWidth()
local screenHeight <const> = playdate.display.getHeight()
local glyphWidth <const> = 20
local numColumns <const> = floor(screenWidth / glyphWidth)
local numRows <const> = floor(screenHeight / glyphWidth)
local numCells <const> = numColumns * numRows
local numStandardGlyphs <const> = 133
local numPDGlyphs <const> = 10
local numTotalGlyphs <const> = numStandardGlyphs + numPDGlyphs
local numFades <const> = 32
local glyphs = {}
do
local glyphSpritesheet = gfx.image.new('images/matrix-glyphs')
local spritesheetColumns = floor(glyphSpritesheet.width / glyphWidth)
local fadeGradient = gfx.image.new('images/fade-gradient')
local glyph = gfx.image.new(glyphWidth, glyphWidth, gfx.kColorBlack)
gfx.pushContext(glyph)
for i = 1, numTotalGlyphs do
local column = (i - 1) % spritesheetColumns
local row = floor((i - 1) / spritesheetColumns)
glyphSpritesheet:draw(-column * glyphWidth, -row * glyphWidth)
glyphs[i] = {}
for j = 1, numFades do
local fade = (j - 1) / (numFades - 1)
local variant = glyph:copy()
glyphs[i][j] = variant
gfx.pushContext(variant)
gfx.setImageDrawMode(gfx.kDrawModeWhiteTransparent);
fadeGradient:draw(fade * (glyphWidth - fadeGradient.width), 0)
gfx.popContext()
end
end
gfx.popContext()
end
local minSpeed <const> = 0.15
local maxSpeed <const> = 1
local time = 0
local speed = maxSpeed
local sineTable = {}
for i = 1,360 do
sineTable[i] = math.sin(math.pi / 180 * i)
end
local wobbleA <const> = math.sqrt(2) / 50
local wobbleB <const> = math.sqrt(5) / 50
local cells = {}
for x = 1, numColumns do
local columnTimeOffset = random() * 1000
local columnSpeedOffset = random() * 0.5 + 0.5
for y = 1, numRows do
local cell = {}
cell.x = x
cell.y = y
cell.glyphCycle = random()
cell.columnTimeOffset = columnTimeOffset
cell.columnSpeedOffset = columnSpeedOffset
cell.glyphIndex = random(numStandardGlyphs)
cell.fadeIndex = -1
cells[#cells + 1] = cell
end
end
playdate.display.setRefreshRate(30)
playdate.resetElapsedTime()
function playdate.update()
local delta
if playdate.isCrankDocked() then
speed = math.min(maxSpeed, speed + 0.07)
delta = playdate.getElapsedTime() * speed
else
speed = math.max(minSpeed, speed - 0.07)
delta = playdate.getElapsedTime() * speed + playdate.getCrankChange() * 2 / 360 -- TODO: tune
end
playdate.resetElapsedTime()
time += delta
local addPDGlyphs = playdate.buttonIsPressed(playdate.kButtonA) and playdate.buttonIsPressed(playdate.kButtonB)
for i = 1, numCells do
local mustDraw = false
local cell = cells[i]
local cellTime = cell.y * -0.03 + cell.columnTimeOffset + time * cell.columnSpeedOffset
local brightness = 4 * (
(
cellTime
+ 0.3 * sineTable[floor((wobbleA * cellTime) % 360) + 1]
+ 0.2 * sineTable[floor((wobbleB * cellTime) % 360) + 1]
) % 1
)
local fadeIndex = floor(brightness * numFades)
if fadeIndex < 1 then fadeIndex = 1 end
if fadeIndex > numFades then fadeIndex = numFades end
if cell.fadeIndex ~= fadeIndex then
cell.fadeIndex = fadeIndex
mustDraw = true
end
cell.glyphCycle = cell.glyphCycle + delta * 2
if cell.glyphCycle > 1 then
cell.glyphCycle = cell.glyphCycle % 1
local lastGlyphIndex = cell.glyphIndex
while cell.glyphIndex == lastGlyphIndex do
if addPDGlyphs and random(4) == 1 then
cell.glyphIndex = random(numPDGlyphs) + numStandardGlyphs
else
cell.glyphIndex = random(numStandardGlyphs)
end
end
if fadeIndex < numFades then
mustDraw = true
end
end
if mustDraw then
glyphs[cell.glyphIndex][cell.fadeIndex]:draw((cell.x - 1) * glyphWidth, (cell.y - 1) * glyphWidth)
end
end
end