LÖVE

Code: Select all

Camera = {}

--------------------------- Basic Functions -||
function Camera:new(o)
	o=o or {}
	setmetatable(o, self)
	self.__index = self
	return o
end

function Camera:init(x, y)
	self.width = love.window.getWidth()
	self.height = love.window.getHeight()
	self.halfWidth = self.width / 2
	self.halfHeight = self.height / 2
	self.x = x
	self.y = y	
	self.rotation = 0
	self.zoom = 1
	self.displayInfo = true
end

function Camera:set()
	love.graphics.push()
	love.graphics.rotate(-self.rotation)
	love.graphics.scale(self.zoom, self.zoom)
	love.graphics.translate(-self.x, -self.y)
	
end

function Camera:unset()
	love.graphics.pop()
end

function Camera:reset()
	self.x = 0
	self.y = 0
	self.rotation = 0
	self.zoom = 1
end

function Camera:move(dx, dy)
	self.x = self.x + (dx or 0)
	self.y = self.y + (dy or 0)
end

function Camera:rotate(dr)
	self.rotation = self.rotation + dr
end

function Camera:scale(amt)
	amt = amt or 1	
	oldZoom = self.zoom
	self.zoom = self.zoom * amt	
	return oldZoom
end

function Camera:setPosition(x, y)
	self.x =  x or self.x
	self.y =  y or self.y
end

function Camera:setScale(amt)	
	self.zoom = amt or self.zoom	
end

function Camera:incScale(amt)
	self.zoom = self.zoom + amt
end
-----------------------------Extra Functions -||
function Camera:inform()
	local info = tostring(self.x) .. ", " .. tostring(self.y)
	love.graphics.print(info, 0, 0)	
	love.graphics.print(self.zoom, 0,  12)
end

function Camera:toggleInfo() 
	self.displayInfo = not self.displayInfo
end

function Camera:draw()
	if self.displayInfo then self:inform() end
end

Code: Select all

require 'camera'
----------------------------Love functions -||
function love.load()
	camera = Camera:new()
	camera:init(0, 0)	
	img = love.graphics.newImage('testShip.png')
	--I start the ship so that it is at the centre of the camera's view 
	shipWorldx = camera.halfWidth  
	shipWorldy = camera.halfHeight 
end

function love.update(dt)
	cameraInputHandling()	--This is here for testing purposes
end

function love.draw()
	camera:set()	
	love.graphics.draw(img, shipWorldx, shipWorldy)		
	camera:unset()
	--Draw a circle at the centre of the screen for reference
	love.graphics.setColor(0, 255, 0)
	love.graphics.circle('fill', camera.halfWidth, camera.halfHeight, 15, 360)
	love.graphics.setColor(255, 255, 255)		
	camera:draw()	 --For now, simply displays camera's world co-ordinates
end

function love.keyreleased(key)
	if key == 'escape' then
		love.event.push('quit')
	end
	if key == 'i' then
		camera:toggleInfo()
	end
	if key == 'r' then
		camera:reset()
	end		
end
--I must be doing something wrong in here...right?
function love.mousepressed(x, y, button) 	if button == 'wu' then	
		local mousex = x - camera.x
		local mousey = y - camera.y
		local lastZoom = camera.zoom
		camera:incScale(0.1)
		local newx = mousex * (camera.zoom / lastZoom)
		local newy = mousey * (camera.zoom / lastZoom)
		local tx = mousex - newx	
		local ty = mousey - newy
		camera:move(tx, ty) 		
	end
	if button == 'wd' then
		local mousex = x - camera.x
		local mousey = y - camera.y
		local lastZoom = camera.zoom
		camera:incScale(-0.1)
		local newx = mousex * (camera.zoom / lastZoom)
		local newy = mousey * (camera.zoom / lastZoom)
		local tx = mousex - newx	
		local ty = mousey - newy
		camera:move(tx, ty) 
	end
end
---------------------------------My functions -||
function cameraInputHandling()
	if love.keyboard.isDown('right') then camera:move(1) end
	if love.keyboard.isDown('left') then camera:move(-1) end
	if love.keyboard.isDown('up') then camera:move(0, -1) end
	if love.keyboard.isDown('down') then camera:move(0, 1) end
end

Code: Select all

function Camera:set()
   love.graphics.push()
   love.graphics.rotate(-self.rotation)
   local w = love.graphics.getWidth() / 2
   local h = love.graphics.getHeight() / 2
   love.graphics.translate(-w, -h)
   love.graphics.scale(self.zoom, self.zoom)
   love.graphics.translate(w - self.x, h - self.y)  
end