Graphics.CopyTexture() Crash on some android mobiles

What I am trying to do is combine their meshes, materials (with same shader and properties except mainTex) and textures all into one, so that I can draw the render, outline and shadow in 3 drawcalls, otherwise it takes 18 drawcalls for each character.

It works pretty good on PC, IOS and some new Android devices. However, I found Graphics.CopyTexture() will cause crash on some android devices, usually mobiles using PowerVR GPU before 2017.

Here is what my code like:

Code (CSharp):

1.  
2.             Texture2D combinedTexture = new Texture2D(dstWidth, dstHeight, format, false);
3.             int gridSzie = textureBuffer[textureBuffer.Count - 1].width;
4.             Vector2 gridFrame = new Vector2(dstWidth / gridSzie, dstHeight / gridSzie);
5.             for (int i = 0; i < textureBuffer.Count; i++)
6.             {
7.                 var gridFill = new Vector2(textureBuffer[i].width / gridSzie, textureBuffer[i].height / gridSzie);
8.                 var offset = FillGrid(gridFill, gridFrame);
9.                 Graphics.CopyTexture(textureBuffer[i], 0, 0, 0, 0, textureBuffer[i].width, textureBuffer[i].height,
10.                     combinedTexture, 0, 0, (int)(offset.x * gridSzie), (int)(offset.y * gridSzie));
11.                 var uvOffset = new Vector2(offset.x / gridFrame.x, offset.y / gridFrame.y);
12.                 var uvScale = new Vector2(gridFill.x / gridFrame.x, gridFill.y / gridFrame.y);
13.                 foreach (var item in textureIndexCache[i])
14.                 {
15.                     uvInfoCache[item] = new UVInfo(uvOffset, uvScale);
16.                 }
17.             }
18.  

BTW, I checked SystemInfo.copyTextureSupport == UnityEngine.Rendering.CopyTextureSupport.None, it returns false.

If I commit Graphics.CopyTexture line, it won't crash. So is there some thing wrong with my code? Is there any other way to avoid Graphics.CopyTexture and copy several compressed textures into one compressed or uncompressed texture? I think the memory consumption is acceptable for this case.

 

BTW, I only find it crashes on two mobile, and there GPU is all Imagination PowerVR G6200.

 

When I tried to check the SystemInfo.copyTextureSupport via Debug.Log(SystemInfo.copyTextureSupport.ToString()), I got output like that: Basic, Copy3D, DifferentTypes, TextureToRT, RTToTexture. Why a single enum has multiple values? How could I do that?

 

Thanks