Milan's magic shaky cam

camera.lua

local camera = {x = 0, y = 0, scaleX = 1, scaleY = 1, rotation = 0, trauma = 0}
local util = require "src.util"
local settings = require "src.settings"

function camera:set()
    local shakeOffsetX, shakeOffsetY, shakeAngle = self:getScreenShake()

    love.graphics.push()
    love.graphics.rotate(self.rotation + shakeAngle)
    love.graphics.scale(self.scaleX, self.scaleY)
    love.graphics.translate(self.x + shakeOffsetX, self.y + shakeOffsetY)
end

function camera:getCenter()
    local centerX = self.x -- + math.floor(love.graphics.getWidth() / self.scaleX * 2)
    local centerY = self.y -- + math.floor(love.graphics.getHeight() / self.scaleY * 2)
    return centerX, centerY
end

function camera:getValues()
    local shakeOffsetX, shakeOffsetY, shakeAngle = self:getScreenShake()
    return self.x + shakeOffsetX, self.y + shakeOffsetY, self.scaleX, self.scaleY, self.rotation + shakeAngle
end

function camera:getScreenShake()
    local screenShake = self.trauma ^ 2
    local shakeAngle = settings.screenShakeAngle * screenShake * util.timeNoise(-1, 1, 1)
    local shakeOffsetX = settings.screenShakeOffset * screenShake * util.timeNoise(-1, 1, 2.5)
    local shakeOffsetY = settings.screenShakeOffset * screenShake * util.timeNoise(-1, 1, 3.1)

    return shakeOffsetX, shakeOffsetY, shakeAngle
end

function camera:addTrauma(trauma)
    self.trauma = math.min(self.trauma + trauma, 1.0)
end

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

function camera:update(dt)
    self.trauma = math.max(self.trauma - settings.traumaDecay * dt, 0.0)
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(sx, sy)
    sx = sx or 1
    self.scaleX = self.scaleX * sx
    self.scaleY = self.scaleY * (sy or sx)
end

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

function camera:moveTowards(x, y)
    self.x = self.x + (x - self.x) * settings.cameraSmoothing
    self.y = self.y + (y - self.y) * settings.cameraSmoothing
end

function camera:setCenterPosition(x, y)
    self.x = x - love.graphics.getWidth() * self.scaleX / 2
    self.y = y - love.graphics.getHeight() * self.scaleY / 2
end

function camera:setScale(sx, sy)
    self.scaleX = sx or self.scaleX
    self.scaleY = sy or self.scaleY
end

function camera:mousePosition()
    -- TODO account for rotation (use hump.vector to rotate)
    return love.mouse.getX() * self.scaleX + self.x, love.mouse.getY() * self.scaleY + self.y
end

return camera