优化两个新背景代码

parts/backgrounds/galaxy.lua

@@ -1,34 +1,34 @@
 --Space with stars
 local gc=love.graphics
 local circle,setColor,hsv=gc.circle,gc.setColor,COLOR.hsv
-local rnd,pi,sin,cos=math.random,math.pi,math.sin,math.cos
+local sin,cos=math.sin,math.cos
 local back={}
 
 local sDist,sRev={},{} -- star data in SoA [distance from center, revolution progress, color]
-local k
 
-local d,r -- temp vars for optimization
 function back.init()
     if sDist[1]then return end
     local max
     for i=0,20 do
         max=16*(i+1)
         for j=1,max do
-            sDist[#sDist+1]=i+rnd()
-            sRev[#sRev+1]=2*pi*j/max+2*pi*rnd()/max
+            sDist[#sDist+1]=i+math.random()
+            sRev[#sRev+1]=MATH.tau*j/max+MATH.tau*math.random()/max
         end
     end
 end
-function back.resize(w,h)k=3*SCR.k end
 function back.update(dt)
-    for i=1,#sDist do sRev[i]=(sRev[i]+dt/(sDist[i]+1))%(2*pi) end
+    for i=1,#sDist do
+        sRev[i]=(sRev[i]+dt/(sDist[i]+1))%MATH.tau
+    end
 end
 function back.draw()
     gc.clear()
     gc.translate(SCR.cx,SCR.cy)
+    gc.scale(SCR.k)
     gc.rotate(1)
     for i=1,#sDist do
-        d,r=sDist[i],sRev[i]
+        local d,r=sDist[i],sRev[i]
         if d<5 then
             setColor(hsv(.088,(d-2)/7,1,.7))
         else
@@ -36,8 +36,6 @@ function back.draw()
         end
         circle('fill',8*d*cos(r),24*d*sin(r),3)
     end
-    gc.rotate(-1)
-    gc.translate(-SCR.cx,-SCR.cy)
 end
-function back.discard()end
+
 return back