Plasma ASCII GPU Buffering Demo For OpenComputers (Version 1.0)

local component = require("component")
local gpu = component.gpu
local computer = require("computer")

local width, height = gpu.getResolution()
local bufferIndex = gpu.allocateBuffer(width, height)

local colorMap = {}
local chars = " .:-=+*#%@"
for i = 0, 255 do
    local value = (i / 255) * 2 - 1
    local index = math.floor((value + 1) * (#chars - 1) / 2) + 1
    colorMap[i] = chars:sub(index, index)
end

local function plasma(x, y, t)
    local value = math.sin(x * 0.1 + t) + math.sin(y * 0.1 + t) +
                  math.sin((x + y) * 0.1 + t) + math.sin(math.sqrt(x * x + y * y) * 0.1 + t)
    return math.floor((value / 4 + 1) * 127.5)
end

local t = 0
local lastTime = computer.uptime()
local frameCount = 0

while true do
    gpu.setActiveBuffer(bufferIndex)

    for y = 1, height do
        for x = 1, width do
            local value = plasma(x, y, t)
            gpu.set(x, y, colorMap[value])
        end
    end

    gpu.setActiveBuffer(0)
    gpu.bitblt(0, 1, 1, width, height, bufferIndex)

    t = t + 0.1
    frameCount = frameCount + 1

    local currentTime = computer.uptime()
    if currentTime - lastTime >= 1 then
        local fps = frameCount / (currentTime - lastTime)
        gpu.set(1, 1, string.format("FPS: %.2f", fps))
        frameCount = 0
        lastTime = currentTime
    end
end