more efficient particles

Former-commit-id: 56dad88ecd715ad6e357e33b903851a47a358dcd
Former-commit-id: c85c0b759a447c0461563d98156f59879fa95db2

src/net/torvald/terrarum/gameactors/ParticleTestRain.kt

@@ -4,21 +4,21 @@ import org.dyn4j.geometry.Vector2
 import org.newdawn.slick.Image
 
 /**
- * Created by SKYHi14 on 2017-01-20.
+ * Created by minjaesong on 2017-01-20.
  */
 class ParticleTestRain(posX: Double, posY: Double) : ParticleBase(ActorOrder.BEHIND, 6000) {
 
     init {
-        image = Image("./assets/graphics/weathers/raindrop.tga")
-        val w = image.width.toDouble()
-        val h = image.height.toDouble()
+        body = Image("./assets/graphics/weathers/raindrop.tga")
+        val w = body.width.toDouble()
+        val h = body.height.toDouble()
         hitbox.setFromWidthHeight(
                 posX - w.times(0.5),
                 posY - h.times(0.5),
                 w, h
         )
 
-        velocity.y = 16.0
+        velocity.y = 10.0
     }
 
 }