Drawing a scaled up and rotated image

[jdse03]

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[zorg]

You are indeed talking about (bi)linear filtering; you just want it to apply only to the rotation, not the scaling.

I don't know if you can do that in one pass though; You'll probably need to use a canvas to render the scaled frame with nearest-neighbour interpolation, and then render that canvas rotated with bilinear interpolation onto the screen.

[jdse03]

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[jdse03]

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[jdse03]

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[zorg]

No code -> no perfect ideas, though i do have a few more tips, like if you're using a sprite atlas, with quads, with or without a spritebatch, i do hope you have 1px borders of the same color of the pixels next to them for each of your sprites, otherwise there will be bleeding when you draw them transformed.

[jdse03]

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[Sasha264]

zorg was right, two staged drawing save a day.
But in your example you have scaling AND rotation in one operation, 90 is rotation in radians, 200 is scale

Code: Select all

love.graphics.draw(player.image, W / 2, H / 2, 90, 200, 200, player.image:getWidth() / 2, player.image:getHeight() / 2)

You want to do this in two stages

Code: Select all

function love.load()
	love.window.setTitle("Cheeeers!! Nearest scale + linear rotation!")
	img = love.graphics.newImage("enemy-mothership.png")
	img:setFilter("nearest", "nearest")
	global_filter = "linear"
	--love.window.setMode(1280, 720, { resizable = false, vsync = true, msaa = 16 }) -- use msaa for better lines, but it greatly decrease performance
end

function love.update(dt)
end

function love.draw()
	-- first draw image without rotation into separate canvas (but with scale)
	local scale = 15
	local w, h = img:getDimensions()
	w, h = w * scale, h * scale
	local canvas = love.graphics.newCanvas(w, h)
	love.graphics.setCanvas(canvas)
	love.graphics.clear()
	love.graphics.draw(img, 0, 0, 0, scale, scale, 0, 0)

	-- second draw canvas into screen with rotation
	local screen_w, screen_h = love.graphics.getDimensions()
	love.graphics.setCanvas()
	love.graphics.draw(canvas, screen_w / 2, screen_h / 2, math.sin(0.5 * love.timer.getTime() / 10), 1, 1, w / 2, h / 2)
end

function love.mousepressed(x, y, button, istouch)
	-- on mouse press I change defauld filtering
	if global_filter == "nearest" then
		global_filter = "linear"
	else
		global_filter = "nearest"
	end
	love.graphics.setDefaultFilter(global_filter, global_filter)
end

[jdse03]

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[zorg]

Yeah, you should create canvases beforehand, since they are reusable (and you can clear them anyway).
You don't really need a gigantic canvas, just use a camera system do draw the relevant area to your canvas, which should be screen-sized at most.