Question Custom ShadowMap Not Working On Mobile

Unity 2022.2.16
URP 14.0.7

I make a custom scriptable renderer pass to render a showmap, then on shader i get shadow via
SAMPLE_TEXTURE2D_SHADOW, is work OK in Editor and PC,but when i build to a Android run on mobile, the sample result is all black. I check the shadowmap renderTexture on the Frame Debuger and it is correct rendering on mobile, so just sample incorrect i guess. it maybe something wrong in other space.

shadowmap on framer debuger,it look ok

    half GetHardShadow(float4 shadowCoord){

        float3 uv = shadowCoord.xyz / shadowCoord.w;

        uv.xy = uv.xy * 0.5 + 0.5;



        if(uv.x<0 || uv.x>1 || uv.y<0 || uv.y>1) return 1.0f;  

 

//SAMPLE_TEXTURE2D_X can sample correct,but not the way i need

       // float atten = SAMPLE_TEXTURE2D_X(_MainLightShadowmapTexture, sampler_MainLightShadowmapTexture, uv);

       

        half atten = SAMPLE_TEXTURE2D_SHADOW(_MainLightShadowmapTexture, sampler_LinearClampCompare, uv ).r;

  return atten;     //this alway return 0 on Android mobile,but correct value on PC  

        atten = LerpWhiteTo(atten, _shadowStrength);

        return atten;

    }

[ATTACH=full]1250218[/ATTACH]

Code (CSharp):

1. var format = UnityEngine.Experimental.Rendering.GraphicsFormatUtility.GetDepthStencilFormat(16, 0);
2.  
3. rtd = new RenderTextureDescriptor(mainLightShadowResolution, mainLightShadowResolution, UnityEngine.Experimental.Rendering.GraphicsFormat.None, format);
4.  
5. rtd.shadowSamplingMode =(RenderingUtils.SupportsRenderTextureFormat(RenderTextureFormat.Shadowmap)&& (SystemInfo.graphicsDeviceType != GraphicsDeviceType.OpenGLES2)) ?ShadowSamplingMode.RawDepth : ShadowSamplingMode.None;
6.  
7. cmd.SetRenderTarget(ri_main_ID, RenderBufferLoadAction.DontCare, RenderBufferStoreAction.DontCare, RenderBufferLoadAction.DontCare, RenderBufferStoreAction.Store);
8. cmd.ClearRenderTarget(true, true, Color.clear);

 

and i got another truble on build to mobile,is my shadowcaster pass shader variants may all strip on build. i got a log like:
STRIPPING: Universal Render Pipeline/CustomPBRLit (CustomShadowCaster pass) (Vertex) - Remaining shader variants = 0/2 = 0% - Total = 1175/79756 = 1.473243% TimeMs=0.2085

it means all the shadowcaster pass variants striped, it's no variants genetate!

 

i test with a new Phone (xiaomi k20 api:Vulkan) today and it's run OK now. i'm confuse if it the last phone's(nexus 6p api:OpenGl) problem, the different of Graphic API ?

 

i guess the problem is only happen on a
not UNITY_REVERSED_Z platform