life_sum.lua

-- life.lua
-- input: mouse, keyboard
-- title:  Life
-- author: Skaruts
-- desc:   A game of life
-- script: lua

local -- shortcuts
floor,      ceil,      max,      min,      abs =
math.floor, math.ceil, math.max, math.min, math.abs

local   -- keys
PGUP, PGDN, CTRL, SHIFT, ALT, SPC, ENT, TAB =
54,   55,   63,   64,    65 , 48,  50,  49
local
A,B,C,D,E,F,G,H,I,J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z =
1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26

local -- mouse, real pos / grid pos / mouse btns
rmx, rmy, mx, my, m1,    m2,    m3 =
0,   0,   0,  0,  false, false, false

local   -- colors
col_bg, col_dead, col_alive, col_selected =
0,      3,        9,         11

-- previous/current/selction cellmaps / dead cells
local pre, cur, draw_d_cells = 1, 2, false
local cells = {}  -- actual cellmaps

-- zoom scalar (higher scalar = smaller cells,
-- 1|2|4|8
local m = 4

-- sprite size
local SS = 8

-- cell size, grid width/height
local CS, GW, GH = SS//m, 30*m, 17*m

 -- padding for cell rects
local pad = (CS == 8) and 2 or (CS == 1 and 0 or 1)

local paused, rand_at_start = true, false

---------------------------------------
--    GAME     ------------------------
---------------------------------------
function init()
    create_cellmaps()
    if rand_at_start then rand_cells() end
end

function TIC()
    update()
    draw()
end

function update()
    rmx, rmy, m1, m2, m3 = mouse()
    mx, my = rmx//CS+1, rmy//CS+1
    mx = clamp(mx, 1, GW)
    my = clamp(my, 1, GH)

    handle_mouse()
    handle_keys()
    if not paused then next_gen() end
end

function draw()
    cls(col_bg)
    if CS > 1 then draw_cells()
    else           draw_pix() end
    if paused then  writec("PAUSED", "x", 0, 0, 6) end
end

function draw_cells()
    for j=1, GH do
        for i=1, GW do
            local x = (i-1) * CS + pad
            local y = (j-1) * CS + pad
            local w, h = CS-pad, CS-pad

            if mx == i and my == j then        rect(x, y, w, h, col_selected)
            elseif cells[cur][j][i] == 1 then  rect(x, y, w, h, col_alive)
            elseif draw_d_cells then           rect(x, y, w, h, col_dead)
            end
        end
    end
end

function draw_pix()
    for j=1, GH do
        for i=1, GW do
            local x = (i-1)
            local y = (j-1)

            if mx == i and my == j then       pix(x, y, col_selected)
            elseif cells[cur][j][i] == 1 then pix(x, y, col_alive)
            elseif draw_d_cells then          pix(x, y, col_dead)
            end
        end
    end
end

function handle_keys()
    if     keyp(SPC)      then pause()
    elseif keyp(G, 20, 5) then next_gen()
    elseif keyp(ENT)      then rand_cells()
    elseif keyp(D)        then toggle_d_cells()
    elseif keyp(C)        then fill_grid(false)
    elseif keyp(F)        then fill_grid(true)
    end
end

function handle_mouse()
    if     m1 then cells[cur][my][mx] = 1
    elseif m3 then cells[cur][my][mx] = 0
    end
end

function pause() paused = not paused end
function toggle_d_cells() draw_d_cells = not draw_d_cells end

function next_gen()
    if algo == SUM then next_gen_sum()
    end
end

function next_gen_sum()
    pre, cur = cur, pre
    for j=1, GH do
        for i=1, GW do
            local n = -- TODO: modify this for optional no-wrapping
                      (cells[pre][ j-1 < 1 and GH or j-1 ][ i-1 <  1 and GW or i-1 ] & 1)
                    + (cells[pre][ j-1 < 1 and GH or j-1 ][ i                      ] & 1)
                    + (cells[pre][ j-1 < 1 and GH or j-1 ][ i+1 > GW and  1 or i+1 ] & 1)
                    + (cells[pre][ j                     ][ i-1 <  1 and GW or i-1 ] & 1)
                    + (cells[pre][ j                     ][ i+1 > GW and  1 or i+1 ] & 1)
                    + (cells[pre][ j+1 > GH and 1 or j+1 ][ i-1 <  1 and GW or i-1 ] & 1)
                    + (cells[pre][ j+1 > GH and 1 or j+1 ][ i                      ] & 1)
                    + (cells[pre][ j+1 > GH and 1 or j+1 ][ i+1 > GW and  1 or i+1 ] & 1)

            local oc = cells[pre][j][i] == 1 -- old cell

            cells[cur][j][i] = num(n==3 or (n==2 and oc))
end end end

function rand_cells()
    for j=1, GH do
        for i=1, GW do
            cells[cur][j][i] = num(math.random() < 0.5)
        end
    end
end

function create_cellmaps()
    for g=1, 2 do cells[g] = {} end

    for j=1, GH do
        for g=1, 2 do cells[g][j] = {} end
        for i=1, GW do
            for g=1, 2 do cells[g][j][i] = 0 end end end
end

function fill_grid(fill)
    for j=1, GH do
        for i=1, GW do
            cells[cur][j][i] = num(enable)
        end end
end

---------------------------------------

--    HELPERS    ----------------------

---------------------------------------
-- print text with drop shadow
function write(txt, x, y, col, fix)
    print(txt, 2+x*8, 2+y*8, 3, fix, 1)
    print(txt, 1+x*8, 1+y*8, col, fix, 1) end

-- print centered with drop shadow
function writec(t, axis, x, y, c, fix)
    if axis == 'x' then
        print(t, 0+(240-print(t, 0, -6))//2, 2+y*SS, 3, fix) -- x
        print(t, (240-print(t, 0, -6))//2, 1+y*SS, c, fix) -- x
    elseif axis == 'y' then
        print(t, 3+x*SS, 1+(136-SS)//2, 3, fix) -- y
        print(t, 2+x*SS, (136-SS)//2, c, fix) -- y
    else
        print(t, 1+(240-print(t, 0, -6))//2, 1+(136-SS)//2, 3, fix) -- xy
        print(t, (240-print(t, 0, -6))//2, (136-SS)//2, c, fix) -- xy
    end
end

function num(v, base)
    if     type(v) == 'boolean' then return v and 1 or 0
    elseif type(v) == 'string' then return base == nil and tonumber(v) or tonumber(v, base)
    else return v == nil and 0 or v end end

function clamp(v, l, h)
    return max(l, min(h, v)) end

init()