nes-audio-vis.lua

----------------------------------------------------------
--  NES audio visualization script   ---------------------
--   by feasel  ~:]     03/19/2013   ---------------------
----------------------------------------------------------


function dutycycle(f)
	-- Width of the ON portion of the square wave (precentage of total cycle)
	if f==0 then
		return "12%"  -- actually 12.5%
	elseif f==1 then
		return "25%"
	elseif f==2 then
		return "50%"
	elseif f==3 then
		return "75%"
	else
		return "???"
	end
end

detailed = true
print("Press 'P' to toggle detailed display")

while true do
	if detailed then gui.text(170, 12, "Press 'P' to hide", "#FFFFFF", "#000000BB") end
	keypress = input.get()
	if keypress.P and not waspressed then
		detailed = not detailed
	end
	waspressed = keypress.P


	rp = sound.get().rp2a03
	s1 = rp.square1
	s2 = rp.square2
	t = rp.triangle
	n = rp.noise
	d = rp.dpcm

	-- DPCM
	y = 25
	d.midikey = math.max(d.midikey, -99)
	d.midikey = math.min(d.midikey, 999)
	if d.dmcloop then dmcLoop = "Loop" else dmcLoop = "    " end
	if detailed then
		gui.text(3, y, string.format("vol=%4.2f frq=%8.1f key=%3d         reg=%3d\naddr=%04X size=%3d %-4s seed=%3d\nPCM", d.volume, d.frequency, d.midikey, d.regs.frequency, d.dmcaddress, d.dmcsize, dmcLoop, d.dmcseed), "#FFFFFF", "#000000BB")
		gui.box((d.dmcaddress-0xB000)*0.0123-2, y+16, (d.dmcaddress-0xB000)*0.0123+2, y+16+d.volume*9+2, "#00FFFF", "#000000AA")
	end
	gui.box((d.dmcaddress-0xB000)*0.0123-2, 185-d.volume*5-1, (d.dmcaddress-0xB000)*0.0123+2, 185+d.volume*5+1, "#00FFFF", "#000000AA")

	-- Square Wave 1
	y = 55
	s1.midikey = math.max(s1.midikey, -99)
	s1.midikey = math.min(s1.midikey, 999)
	if detailed then
		gui.text(3, y, string.format("vol=%4.2f frq=%8.1f key=%3d wide=%-3s reg=%3d\nSqr1", s1.volume, s1.frequency, s1.midikey, dutycycle(s1.duty), s1.regs.frequency), "#FFFFFF", "#000000BB")
		gui.box(s1.midikey*1.3-1-s1.duty, y+8, s1.midikey*1.3+1+s1.duty, y+9+s1.volume*15, "#FF0000", "#000000AA")
	end
	gui.box(s1.midikey*1.3-1-s1.duty, 195-s1.volume*8-1, s1.midikey*1.3+1+s1.duty, 195+s1.volume*8+1, "#FF0000", "#000000AA")

	-- Square Wave 2
	y = 85
	s2.midikey = math.max(s2.midikey, -99)
	s2.midikey = math.min(s2.midikey, 999)
	if detailed then
		gui.text(3, y, string.format("vol=%4.2f frq=%8.1f key=%3d wide=%-3s reg=%3d\nSqr2", s2.volume, s2.frequency, s2.midikey, dutycycle(s2.duty), s2.regs.frequency), "#FFFFFF", "#000000BB")
		gui.box(s2.midikey*1.3-1-s2.duty, y+8, s2.midikey*1.3+1+s2.duty, y+9+s2.volume*15+1, "#0000FF", "#000000AA")
	end
	gui.box(s2.midikey*1.3-1-s2.duty, 205-s2.volume*8-1, s2.midikey*1.3+1+s2.duty, 205+s2.volume*8+1, "#0000FF", "#000000AA")

	-- Triangle Wave
	y = 115
	t.midikey = math.max(t.midikey, -99)
	t.midikey = math.min(t.midikey, 999)
	if detailed then
		gui.text(3, y, string.format("vol=%4.2f frq=%8.1f key=%3d         reg=%3d\nTriangle", t.volume, t.frequency, t.midikey, t.regs.frequency), "#FFFFFF", "#000000BB")
		gui.box(t.midikey*1.3-2, y+8, t.midikey*1.3+2, y+9+t.volume*15+1, "#00FF00", "#000000AA")
	end
	gui.box(t.midikey*1.3-2, 215-t.volume*5-1, t.midikey*1.3+2, 215+t.volume*5+1, "#00FF00", "#000000AA")

	-- Noise
	y = 145
	n.midikey = math.max(n.midikey, -99)
	n.midikey = math.min(n.midikey, 999)
	if n.short then noiseLen="short" else noiseLen="long" end
	if n.short then color="#CFCFCF"  else color="#8F8F8F" end
	if n.short then w=1              else w=2             end
	if detailed then
		gui.text(3, y, string.format("vol=%4.2f frq=%8.1f key=%3d %5s    reg=%3d\nNoise", n.volume, n.frequency, n.midikey, noiseLen, n.regs.frequency), "#FFFFFF", "#000000BB")
		gui.box(n.midikey*1.3-w, y+8, n.midikey*1.3+w, y+9+n.volume*15+1, color, "#000000AA")
	end
	gui.box(n.midikey*1.3-w, 225-n.volume*8-1, n.midikey*1.3+w, 225+n.volume*8+1, color, "#000000AA")

	emu.frameadvance()
end