lua-test-202107092059

lua-test/main.lua

@@ -1,3 +1,5 @@
+local fov = 90 * math.pi / 180
+
 local playerx = 10
 local playery = 10
 local angle = 0
@@ -6,9 +8,15 @@ local playerspeed = 0
 local playerswspeed = 0
 local playermaxspeed = 100
 
+function love.load()
+	love.mouse.setRelativeMode(true)
+end
+
+function love.mousemoved(x, y, dx, dy)
+	angle = angle - dx / love.graphics.getWidth() * 2 * math.pi
+end
+
 function love.update(dt)
-	local mousex, mousey =  love.mouse.getPosition()
-	angle = -(mousex / love.graphics.getWidth()) + 0.5
 	playerx = playerx + math.sin(angle) * playerspeed * dt
 	playerx = playerx + math.cos(angle) * playerswspeed * dt
 	playery = playery + math.cos(angle) * playerspeed * dt
@@ -24,6 +32,12 @@ function love.keypressed(key)
 		playerswspeed = playerswspeed + playermaxspeed
 	elseif key == 'd' then
 		playerswspeed = playerswspeed - playermaxspeed
+	elseif key == 'o' then
+		fov = fov + 10 * math.pi / 180
+	elseif key == 'p' then
+		fov = fov - 10 * math.pi / 180
+	elseif key == 'q' then
+		love.event.quit()
 	end
 end
 
@@ -39,8 +53,6 @@ function love.keyreleased(key)
 	end
 end
 
-local fov = 90 * math.pi / 180
-
 function transform(wx, wy)
 	-- Player-relative space (translation)
 	local tx = wx - playerx
@@ -54,34 +66,104 @@ function transform(wx, wy)
 	-- Player-relative x maps to *-x*
 	-- Player-relative y maps to *z*
 	local px = -rx / ry / math.tan(fov / 2)
-	local pz = ry
 
 	-- Screen space (scaling and translation)
 	local hwidth = love.graphics.getWidth() / 2
 	local x = px * hwidth + hwidth
+	local z = ry
 
-	return x, pz
+	return x, z
 end
 
 function drawWall(wx1, wy1, wx2, wy2)
 	local hwidth = love.graphics.getWidth() / 2
 	local hheight = love.graphics.getHeight() / 2
-	love.graphics.setColor(255, 0, 0)
-	love.graphics.line(wx1 + hwidth, wy1 + hheight, wx2 + hwidth, wy2 + hheight)
-
 	local x1, z1 = transform(wx1, wy1)
 	local x2, z2 = transform(wx2, wy2)
 
-	love.graphics.setColor(255, 255, 255)
-	love.graphics.line(x1, hheight - 60 * hheight / z1 / math.tan(fov / 2), x2, hheight - 60 * hheight / z2 / math.tan(fov / 2))
-	love.graphics.line(x1, hheight + 60 * hheight / z1, x2, hheight + 60 * hheight / z2)
+	if z1 < 0 and z2 < 0 then
+		love.graphics.setColor(0.8, 0.7, 0.7)
+		love.graphics.line(wx1 + hwidth, wy1 + hheight, wx2 + hwidth, wy2 + hheight)
+		-- Fully outside of viewport, don't bother
+		return
+	end
+
+	love.graphics.setColor(1, 0, 0)
+	love.graphics.line(wx1 + hwidth, wy1 + hheight, wx2 + hwidth, wy2 + hheight)
+
+	if z1 < 0 or z2 < 0 then
+		local clippingx = playerx + 0.001*math.sin(angle)
+		local clippingy = playery + 0.001*math.cos(angle)
+
+		local x = nil
+		local y = nil
+
+		if wx2 ~= wx1 then
+			local clippingslope = -math.sin(angle)/math.cos(angle)
+			local wallslope = (wy2 - wy1)/(wx2 - wx1)
+			x = (-clippingslope*clippingx + clippingy + wallslope*wx1 - wy1)/(wallslope - clippingslope)
+			y = wallslope*(x - wx1) + wy1
+		else
+			local perclippingslope = -math.cos(angle)/math.sin(angle)
+			local perwallslope = (wx2 - wx1)/(wy2 - wy1)
+			y = (-perclippingslope*clippingy + clippingx + perwallslope*wy1 - wx1)/(perwallslope - perclippingslope)
+			x = perwallslope*(y - wy1) + wx1
+		end
+
+		if z1 < 0 then
+			x1, z1 = transform(x, y)
+			love.graphics.setColor(0.8, 0.5, 0.5)
+			love.graphics.line(wx1 + hwidth, wy1 + hheight, x + hwidth, y + hheight)
+		else
+			x2, z2 = transform(x, y)
+			love.graphics.setColor(0.8, 0.5, 0.5)
+			love.graphics.line(x + hwidth, y + hheight, wx2 + hwidth, wy2 + hheight)
+		end
+	end
+
+	local wall1 = hwidth * 60 / z1 / math.tan(fov / 2)
+	local wall2 = hwidth * 60 / z2 / math.tan(fov / 2)
+
+	love.graphics.setColor(1, 1, 1)
+	love.graphics.line(x1, hheight - wall1, x2, hheight - wall2)
+	love.graphics.line(x1, hheight + wall1, x2, hheight + wall2)
+	love.graphics.line(x1, hheight - wall1, x1, hheight + wall1)
+	love.graphics.line(x2, hheight - wall2, x2, hheight + wall2)
+
+	if z1 < 0 then
+		love.graphics.setColor(0, 0, 1)
+		square = {
+			wx1 - 5 + hwidth, wy1 - 5 + hheight,
+			wx1 + 5 + hwidth, wy1 - 5 + hheight,
+			wx1 + 5 + hwidth, wy1 + 5 + hheight,
+			wx1 - 5 + hwidth, wy1 + 5 + hheight,
+		}
+		love.graphics.polygon('fill', square)
+		love.graphics.line(hwidth+playerx, hheight+playery, hwidth+wx1, hheight+wy1)
+	end
+	if z2 < 0 then
+		love.graphics.setColor(0, 0, 1)
+		square = {
+			wx2 - 5 + hwidth, wy2 - 5 + hheight,
+			wx2 + 5 + hwidth, wy2 - 5 + hheight,
+			wx2 + 5 + hwidth, wy2 + 5 + hheight,
+			wx2 - 5 + hwidth, wy2 + 5 + hheight,
+		}
+		love.graphics.polygon('fill', square)
+		love.graphics.line(hwidth+playerx, hheight+playery, hwidth+wx2, hheight+wy2)
+	end
 end
 
 function love.draw()
 	local hwidth = love.graphics.getWidth() / 2
 	local hheight = love.graphics.getHeight() / 2
 
-	drawWall(-300, 100, 300, 100)
+	drawWall(-300, -200, -200, 100)
+	drawWall(-150, 200, 300, 200)
+	drawWall(300, 200, 300, -200)
+	drawWall(300, -200, -300, -200)
 
-	drawWall(playerx, playery, playerx + math.sin(angle) * 5, playery + math.cos(angle) * 5)
+	love.graphics.setColor(0, 1, 0)
+	love.graphics.line(hwidth+playerx, hheight+playery, hwidth+playerx + math.sin(angle + fov/2) * 5, hheight+playery + math.cos(angle + fov/2) * 5)
+	love.graphics.line(hwidth+playerx, hheight+playery, hwidth+playerx + math.sin(angle - fov/2) * 5, hheight+playery + math.cos(angle - fov/2) * 5)
 end