Massive Lag

Unity Engine
,
1

After working with Unity for a while, I decided to start using Unity for my iPhone games. Once I bought it however, I noticed many of the features didn’t work half as well as on a computer.

For instance, running at 11.4k Tris and 22 drawcalls, It’s nearly impossible to navigate around due to the lag.

Next, I’ve noticed many shaders don’t work either

Shader "Terrain/AlphaBlended" {
	Properties {
		_MainTex ("Base (RGB)", 2D) = "white" {}
		_DetailTex ("Detail (RGB)", 2D) = "white" {}
		_LowTex ("Low (RGB)", 2D) = "white" {}
		_BlendMap ("BlendMap (RGBA)", 2D) = "white" {}
		_LightMap ("LightMap (RGB)", 2D) = "white" {}
	}
	SubShader {
		Pass {
			Material {
				Diffuse (1,1,1,1)
				Ambient (1,1,1,1)
			}
			Lighting On
			BindChannels {
             	 Bind "vertex", vertex
           		 Bind "color", color
           		 Bind "texcoord", texcoord

        	}

			
			SetTexture [_BlendMap] {
				Combine texture
			}
			
			SetTexture [_DetailTex] {
				Combine texture * previous
			}
			


			SetTexture [_MainTex] {
				Combine previous lerp (previous) texture
			}
			
			SetTexture [_LightMap] {
				Combine previous * texture
			}
			
			
		}
	} 
	FallBack "Diffuse", 1
}

Next, when I add trees to the random terrain generator I coded, it lags to about 2 frames/second. Am I missing something, or did I just get ripped off?

2

well IOS is a whole another beast you can’t expect it will just run like on your PC out of the box , it won’t ,

you need to doc yourself on it and learn how to optimize your stuff regarding the platform you target ( with it constraint ) be it artwork side or code side.

there various level of opti in this regard.

shader wise o am not expert , but well in general idea , you need to optimize them for iOS or at least use what unity provide for mobile shader and do not rely on shader provided in PC or MAC stuff

3

You need to optimise all the shaders. You don’t actually need to worry much about draw calls but a quick guide what to avoid:

  • all terrain stuff
  • textures bigger than 512x512
  • shaders which aren’t in the mobile folder
  • alpha test (big no no)
  • overdraw / fill rate (lots of transparent stuff)
  • more than one light
4

You’ve got several things in that shader that are doing nothing but eating performance and/or being useless. You’re saying that you want vertex colors, but then you overwrite them with vertex lighting, and you never use the lighting anyway. _LowTex isn’t used anywhere.

What is in _BlendMap that necessitates a blend with _DetailTex? If nothing, then you can make this easy. Otherwise, you can at least save a multiply; the POWERVR hardware is scalar, not vector, so it does matter.

Chiefly, though, you need to know that you can’t use more than two texture combiners if you emulate/target the MBXLite.