Witch Game Explosions

explode.p8

-- Created for my Ko-fi article about my game
-- dev journey with my witch smup game
-- https://ko-fi.com/post/ENGHUN-Unnamed-Project--Making-Abilites-Look-B-X8X2DH3X2

-- Code is In progress, heavily not optimized
-- and geared towards readability until PICO_8
-- token counts come into play


-- creating the particles. We use sx and sy parameters
-- for movement later and _clr to determine our color 
-- values. Notice the first bigger size particle we add
-- which is the middle white flash
function explode_part(_x, _y, _tpe, _clr)
	local part = {
		x = _x,
		y = _y,
		sx = 0, 
		sy = 0,
		age = 0+rnd(10),
		size = 3+rnd(3),
		maxAge = 5 + rnd(10),
		tpe = _tpe,
		clr = 7,
		sclr = 7
	}
	add(particles, part)
	for i=1,10 do
		local part = {
			x = _x,
			y = _y,
			sx = rnd()*4-2, 
			sy = rnd()*4-2,
			age = 0+rnd(10),
			size= 1+rnd(2),
			maxAge = 30 + rnd(10),
			tpe = _tpe,
			clr = _clr,
			sclr = _clr
		}
		add(particles, part)
	end
end

-- in update we check for the color and update our
-- fading colors based on a table we determine
-- this way it is easy to add or modify new color fades

function update_particles()
	-- pink and blue part colors shades, 14, 12, 7
	local partColors = {{8,2}, {1,5}, {6,5}}
	for part in all(particles) do
		local colorIndex = 1
		if part.sclr == 12 then colorIndex = 2 end
		if part.sclr == 7 then colorIndex = 3 end

    -- update position
		part.x += part.sx
		part.y += part.sy
		part.age+=1
    
    -- we let circle explosions to fade aways
    -- before deleting them after they reach
    -- their lifetime
		if part.age >= part.maxAge then
			if not (part.tpe == "circle") then
				del(particles, part)
			else
				part.size=part.size*0.9
				if part.size <= 1 then
					del(particles, part)
				end
			end
		end

    -- setting the color fades for the explosion particles
		if (part.tpe == "dot") or (part.tpe == "circle") then
			if part.age > 10 then
				part.clr = partColors[colorIndex][1]
			end
			if part.age > 20 then
				part.clr = partColors[colorIndex][2]
			end
		end

    -- applying simulated friction to slowly diminish speed
		part.sx = part.sx * 0.9
		part.sy = part.sy * 0.9
	end
  -- shockwaves for later
	for sw in all(shockwaves) do
		sw.size += sw.spd
		if sw.size > sw.targetSize then
			del(shockwaves, sw)
		end
	end
end

-- we just iterate through our collection
-- and draw the particle accordingly of it's
-- type
function draw_particles()
	for part in all(particles) do
		if part.tpe == "circle" then
			circfill(part.x, part.y, part.size, part.clr)
		elseif part.tpe == "dot" then
			pset(part.x, part.y, part.clr)
		end
	end
	for sw in all(shockwaves) do
		circ(sw.x+rnd()*5, sw.y+rnd()*5, sw.size, sw.clr)
	end
end