PICO-8 grid rajzolás v1.0

-- grid initialization in _init
function _init()
    grid_timer = 0
    -- increase this to make the drawing faster 
    -- (e.g., 1 = one sprite/frame, 16 = one full line/frame if width is 16)
    fill_rate = 8 
    grid_done = false
end

function _update()
    -- only increment timer if the grid animation is not yet finished
    if not grid_done then
        grid_timer += fill_rate
    end
end

function _draw()
    cls(0) -- clear screen to black

    -- call the grid drawing function
    -- parameters:
    -- x:8, y:8 -> starting top-left pixel coordinates
    -- dx:14, dy:14 -> grid dimensions (14x14 sprites)
    draw_retro_grid(8, 8, 14, 14)
end

---------------------------------------------------
-- retro grid drawing function
---------------------------------------------------
-- x,y: top-left corner of the entire grid
-- dx,dy: number of columns and rows
---------------------------------------------------
function draw_retro_grid(x, y, dx, dy)
    local spr_s = 8 -- standard pico-8 sprite size (8x8 pixels)
    local total_sprites = dx * dy
    
    -- current number of sprites to display based on the timer
    local current_count = flr(grid_timer)
    
    -- cap the count at the maximum number of sprites
    if current_count >= total_sprites then
        current_count = total_sprites
        grid_done = true
    end

    -- iterate through all sprites that should be visible currently
    for i = 0, current_count - 1 do
        -- calculate logical row and column
        -- using 'i' ensures we follow a specific sequence
        local current_row = flr(i / dx)
        local current_col = i % dx
        
        -- calculate screen coordinates:
        -- (dx - 1 - current_col) starts drawing from right to left
        local spr_x = x + ((dx - 1 - current_col) * spr_s)
        
        -- (dy - 1 - current_row) starts drawing from bottom to top
        local spr_y = y + ((dy - 1 - current_row) * spr_s)
        
        -- draw sprite #0 from the sprite sheet
        spr(0, spr_x, spr_y)
    end
end