chunk-based rendering

1 files changed, 54 insertions, 11 deletions

diff --git a/main.lua b/main.lua
index 84fb787..ebef333 100644
--- a/main.lua
+++ b/main.lua
@@ -4,11 +4,11 @@ local obj = require "obj"
 obj.load_types()
 line = love.graphics.line
 set_color = love.graphics.setColor
-love.graphics.setLineWidth(0.5)
 
+line_width = 0.4
 local cam = {
 	x = 0, y = 0,
-	scale = 256,
+	scale = 1.1,
 	panning = false,
 }
 
@@ -19,25 +19,64 @@ for i = 1, 100 do
 	})
 end
 
-local function view_scale()
+obj.new("test", {0, 0})
+
+local function window_scale()
 	local w, h = love.graphics.getDimensions()
-	return cam.scale / math.min(w, h)
+	return 256 / math.min(w, h)
 end
 
-local function view_transform()
+local function view_scale()
+	return window_scale() / cam.scale
+end
+
+local function view_dimensions()
+	local w, h = love.graphics.getDimensions()
 	local scale = view_scale()
+	return w * scale, h * scale
+end
+
+local function window_transform()
+	local scale = window_scale()
 	local trans = love.math.newTransform(0, 0, 0, 1/scale, 1/scale)
-	trans:translate(cam.x, cam.y)
+	return trans
+end
+
+local function view_transform()
+	local w, h = view_dimensions()
+	local trans = window_transform()
+	trans:scale(cam.scale, cam.scale)
+	trans:translate(-cam.x + w/2, -cam.y + h/2)
 	return trans
 end
 
 function love.draw()
-	love.graphics.clear(0,0,0)
+	love.graphics.clear(0, 0, 0)
+	local w, h = view_dimensions()
+	local cx1, cy1 = cam.x - w/2, cam.y - h/2
+	local cx2, cy2 = cam.x + w/2, cam.y + h/2
+
 	love.graphics.applyTransform(view_transform())
-	for _, o in pairs(world.objects) do
-		love.graphics.setColor(1, 1, 1)
+	-- the line thickness will scale according to the zoom amount. counteract this.
+	love.graphics.setLineWidth(line_width / cam.scale)
+	-- draw a grid
+	set_color(0.1, 0.1, 0.1)
+	for x = cx1 - cx1%64, cx2, 64 do
+		for y = cy1 - cy1%64, cy2, 64 do
+			line(x, y, x + world.chunk_size, y)
+			line(x, y, x, y + world.chunk_size)
+		end
+	end
+	-- draw all possibly visible objects
+	for o in world.iterate(cx1 - 20, cy1 - 20, cx2 + 20, cy2 + 20) do
+		set_color(1, 1, 1)
 		o:draw()
 	end
+	love.graphics.origin()
+
+	love.graphics.applyTransform(window_transform())
+	love.graphics.setLineWidth(line_width)
+	set_color(1, 1, 1)
 end
 
 function love.update()
@@ -62,7 +101,11 @@ function love.mousemoved(_, _, dx, dy)
 	if cam.panning then
 		local scale = view_scale()
 		dx, dy = dx * scale, dy * scale
-		cam.x = cam.x + dx
-		cam.y = cam.y + dy
+		cam.x = cam.x - dx
+		cam.y = cam.y - dy
 	end
 end
+
+function love.wheelmoved(_, y)
+	cam.scale = math.min(math.max(cam.scale + (y * 0.1), 0.25), 4)
+end