Merge remote-tracking branch 'love_plotting/master'

main.lua

@@ -0,0 +1,165 @@
+function lerp(x0, x1, t)
+	return x0*(1-t) + x1*t
+end
+
+function blendExp(x0, x1, t)
+	return x0^(1-t)*x1^t
+end
+
+local sw = 640
+local sh = 480
+
+local font
+local fs = 12
+
+local coordsA = {}
+local coordsB = {}
+local coordsAL = {}
+local coordsBL = {}
+
+local input = {
+	  [0]=0.9013,
+	 [60]=1.3685,
+	[120]=1.1046,
+	[180]=1.1633,
+	[240]=0.7332,
+	[300]=0.8603,
+	[360]=0.9013,
+}
+local xPrecision = 60/20
+
+local win = {
+	T = 1.5,
+	B = -0.5,
+	L = 0,
+	R = 360,
+	stepX = 30,
+	stepY = 0.25,
+}
+win.scaleX = 1/(win.L - win.R)
+win.scaleY = 1/(win.T - win.B)
+
+function screenX(x)
+	return sw*(win.L-x)*win.scaleX
+end
+
+function screenY(y)
+	return sh*(win.T-y)*win.scaleY
+end
+
+function addPoint(coords, x, y)
+	coords[#coords+1] = screenX(x)
+	coords[#coords+1] = screenY(y)
+end
+
+function index(t, x)
+	if type(x) ~= type(0) then
+		return nil
+	end
+
+	local x0
+	local x1
+	for tx, ty in pairs(t) do
+		-- we can't guarantee the order the key/values come in
+		if tx ~= "interpolator" then
+			-- x0 = largest tx that doesn't go over x
+			if tx <= x and (x0 == nil or tx > x0) then
+				x0 = tx
+			end
+			-- x1 = smallest tx that doesn't go under x
+			if tx > x and (x1 == nil or tx < x1) then
+				x1 = tx
+			end
+		end
+	end
+	x1 = x1 or x0
+
+	local y0 = rawget(t, x0)
+	local y1 = rawget(t, x1)
+	local f = rawget(t, "interpolator")
+	local y = f(y0, y1, (x - x0)/(x1 - x0))
+	return y
+end
+
+function love.load()
+	if not love.graphics.setMode(sw, sh) then
+		error("couldn't setMode ("..sw.." by "..sh..")")
+	end
+
+	love.graphics.setCaption("hey it's a graph")
+
+	--font = love.graphics.newFont("DejaVuSansMono.ttf", fs)
+	--love.graphics.setFont(font)
+	setmetatable(input, {__index = index})
+
+	input.interpolator = lerp
+	for x=win.L, win.R, xPrecision do
+		local y = input[x]
+		addPoint(coordsA, x, y)
+		addPoint(coordsAL, x, math.log(y))
+	end
+
+	input.interpolator = blendExp
+	for x=win.L, win.R, xPrecision do
+		local y = input[x]
+		addPoint(coordsB, x, y)
+		addPoint(coordsBL, x, math.log(y))
+	end
+end
+
+function love.keypressed(key)
+	if key == "escape" then
+		love.event.push("quit")
+	end
+end
+
+local drawCoords = love.graphics.line
+local drawText = love.graphics.print
+
+function color(hex)
+	local r = tonumber(string.sub(hex, 1,2), 16)
+	local g = tonumber(string.sub(hex, 3,4), 16)
+	local b = tonumber(string.sub(hex, 5,6), 16)
+	love.graphics.setColor(r,g,b)
+end
+
+function drawVert(x)
+	drawCoords(x, 0, x, sh)
+end
+
+function drawHoriz(y)
+	drawCoords(0, y, sw, y)
+end
+
+function love.draw()
+	love.graphics.setBackgroundColor(255,255,255)
+	love.graphics.clear()
+
+	for x=win.L, win.R, win.stepX do
+		color("d3e2e7")
+		local rx = screenX(x)
+		drawVert(rx)
+		color("808080")
+		drawText(tostring(x), rx, sh - fs)
+	end
+
+	for y=win.B, win.T, win.stepY do
+		color("c6cce3")
+		local ry = screenY(y)
+		drawHoriz(ry)
+		color("808080")
+		drawText(tostring(y), 0, ry)
+	end
+
+	color("404040")
+	drawVert(screenX(0))
+	drawHoriz(screenY(0))
+
+	color("57C1BB")
+	drawCoords(coordsA)
+	drawCoords(coordsAL)
+
+	color("9F65C5")
+	drawCoords(coordsB)
+	drawCoords(coordsBL)
+end