Questions about maximum texture size can be used in iOS

I want to show a panorama on a "SkySphere" in my project. The original size of the image(panorama used as the texture) is 4096 * 1583.

I use a very simple shader to set this texture to a sphere object:

Code (csharp):

1. Shader "SkySphere" {
2.     Properties {
3.         _MainTex ("Base (RGB)", 2D) = "white" {}
4.     }
5.    
6.     SubShader {
7.         Pass {
8.             Cull Front
9.             SetTexture [_MainTex]
10.         }
11.     }
12. }
13.  

Every works fine in the editor using Unity Remote on iPad. But after I port it to the real iPad, I only see a black screen. Then I try to reduce texture size to 2048, this works fine on the iPad device. Here are 2 screen-shot to show the setting of the imported texture:



The only difference of the settings is "Max Size".

So my questions are:
1. Does 2048 is the max size that iOS (OpenGL ES 2.0) support?
2. If not what's the limit?
3. Are there some other ways to implement a high res "SkySphere" in Unity, even bigger than 4096?

Thanks for help.

 

The max size depends on the hardware. Pre-3GS is 1024, after that is 2048. Also, you need square power-of-two sized textures to be able to use compression.

--Eric

 

Thanks, my friends.

 

Considering your given example i would recalculate (change proportions) your panorama pic to 2546 x 2546 (this equals your 4096 x 1583 resolution size) and then resize it to 2048x2048 to take advantage of compression.

 

why are you scaling up then down instead of just scaling down?

 

Hello, I've materials with tiled textures. Now it bakes from the tiled textures one big texture atlas. So a wall material with 10x10 brick textures becomes one big 10x10 brick in the texture atlas, is there also a way to get only one brick texture in the atlas and keep the end result tiled? I tried fix out of bound uv's but I'm not really getting if it is possible to keep tiled material without getting a big texture atlas.

Thanks