Upgrading Shader...

I'm trying to upgrade a postprocessing shader that worked in legacy, but there seems to be some missing shader functions. In particular, I need these:

• UnityStereoTransformScreenSpaceTex(float uv)
• Linear01Depth(float depth)
• SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture, texcoord)

SAMPLE_DEPTH_TEXTURE() seems to exist, but the parameters seem to have changed?

There are also the new TEXTURE2D_X() and LOAD_TEXTURE2D_X() functions. Does anyone know what these are doing different from a the old tex2D() functions?

 

Sorry to bump.
No depth-related post processing is possible without theses functions, so surely other people are having issues with this?

 

hey,
inside ShaderVariables.hlsl you have this function that can help you to sample the depth

Code (CSharp):

1.  
2. float LoadCameraDepth(uint2 pixelCoords)
3. {
4.     return LOAD_TEXTURE2D_X_LOD(_CameraDepthTexture, pixelCoords, 0).r;
5. }
6.  

also note that they are multiplying the uv by the screen size like so

Code (CSharp):

1. float SampleCameraDepth(float2 uv)
2. {
3.     return LoadCameraDepth(uint2(uv * _ScreenSize.xy));
4. }

 

Thanks for the reply. The ShaderVariables.hlsl is a good resource for a lot of the missing things. I thought I'd share some of my findings here (since there doesn't seem to be any documentation for this elsewhere).

unity_CameraInvProjection has changed into _InvProjMatrix (you can find a bunch of other camera matrices in ShaderVariables.hlsl).

The _X on TEXTURE2D_X means that it is a screen texture that is capable of being different for each eye (in VR). For this reason, all your screen texture functions should have _X on the end (such as TEXTURE2D_X(tex) and LOAD_TEXTURE2D_X(tex, uv)).

You usual texture will just use TEXTURE2D, TEXTURE2D_FLOAT, etc. To sample these, you must specify a sampler. You can do that like this:

Code (CSharp):

1.  
2. // declare
3. TEXTURE2D(_MainTex);
4. SAMPLER(sampler_MainTex);
5.  
6. // use
7. float4 color = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, uv);
8.  

Linear01Depth doesn't exist, and there doesn't seem to be a replacement, however it is quite easy to replace it with your own:

Code (CSharp):

1. inline float Linear01Depth( float z )
2. {
3.     return 1.0 / (_ZBufferParams.x * z + _ZBufferParams.y);
4. }

UnityStereoTransformScreenSpaceTex(uv) no longer exists. You can use UNITY_SETUP_STEREO_EYE_INDEX_POST_VERTEX(input) instead.

I have also noticed some other things which I think are bugs but, once again, it might just be that these things haven't been documented:

• Custom post processing won't work if your CustomPostProcessVolumeComponent class is in a namespace. This makes it not very asset-friendly.
• material.EnableKeyword() doesn't seem to work with post processing at all. This is a major deal breaker and is blocking me for achieving what I need.

Does anyone know how to solve these issues?

 

Sorry to bump again, but has anyone been able to use material/shader keywords in the new post processing?

 

Is there any documentation for this new API and macros?
@stu_pidd_cow is this keywords switching problem fixed? I never experienced keyword problems before.

 

@stu_pidd_cow
Keywords shouldn't cause any problem, at least I haven't had since last August or so when I converted my post effects to HDRP.
In C#: (this is just from my code...)

Code (CSharp):

1. m_Material.EnableKeyword("ADJUST_CONTRAST");
2. m_Material.DisableKeyword("ADJUST_CONTRAST");

Then in shader:

Code (CSharp):

1. #pragma multi_compile __ ADJUST_CONTRAST

If I remember correctly I had to use that double underscore for some reason? Maybe for toggling on and off to work? But don't quote me on that, I need to test it as I've forgotten why. But I'm sure toggles work as I use tens of those in many effects.

Then the actual use case:

Code (CSharp):

1. #ifdef ADJUST_CONTRAST
2.    color.rgb = AdjustContrast(color.rgb, _Contrast);
3. #endif

This thread also has good information about post processing related things:
https://forum.unity.com/threads/custom-post-processing-effects-with-new-hdrp-workflow.689317/

I posted there months ago some info about depth, normals and motion vectors. (And there's other good info too, of course.)

 

@Lynxed it's best to just dig into the code... I used a text editor to seach the files and just took shots in the dark with some words I thought might be there like depth, normals and so on . There's plenty of code that gives good pointers but it's really disturbing that there's no documentation.

 

I'm following keijiro's Kino HDRP custom postprocess examples and trying to use TEXTURE2D_X as they do is, but i get shader error: unrecognized identifier 'TEXTURE2D_ARRAY' at line 19 (on d3d11).

This shader is not working:

Code (CSharp):

1. Shader "ForOfWar/FogOfWarPostProcessShader"
2. {
3.  
4.         SubShader
5.         {
6.  
7.             //0 - Final Post Process Pass
8.             Pass
9.             {
10.                 HLSLPROGRAM
11.  
12.                 #pragma vertex Vertex
13.                 #pragma fragment Fragment                      
14.  
15.                 #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Common.hlsl"
16.                 #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Color.hlsl"
17.                 #include "Packages/com.unity.render-pipelines.high-definition/Runtime/ShaderLibrary/ShaderVariables.hlsl"
18.  
19.                 TEXTURE2D_X _MainTex;
20.                 TEXTURE2D_X _FowMeshMap;
21.  
22.  
23.                 float3 _WorldSpaceCameraMainPos;
24.                 float3 _OriginPosition;
25.                 float4x4 _ClipToWorld;
26.  
27.                 struct Attributes
28.                 {
29.                     uint vertexID : SV_VertexID;
30.                     float2 uv   : TEXCOORD0;
31.                     UNITY_VERTEX_INPUT_INSTANCE_ID
32.                 };
33.  
34.                 struct Varyings
35.                 {
36.                     float4 positionCS : SV_POSITION;
37.                     float2 uv   : TEXCOORD0;
38.                     float3 worldDir: TEXCOORD1;
39.                     UNITY_VERTEX_OUTPUT_STEREO
40.                 };
41.  
42.  
43.                 Varyings Vertex(Attributes input)
44.                 {
45.                     Varyings output;
46.                     UNITY_SETUP_INSTANCE_ID(input);
47.                     UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(output);
48.                     output.positionCS = GetFullScreenTriangleVertexPosition(input.vertexID);              
49.                     output.uv = input.uv;
50.                     output.worldDir = (mul(_ClipToWorld, float4((output.uv * 2) - 1, 0.0, 1.0)) - _WorldSpaceCameraMainPos);
51.                     return output;
52.                 }
53.  
54.                 float LinearEyeDepth(float z)
55.                 {
56.                     return 1.0 / (_ZBufferParams.z * z + _ZBufferParams.w);
57.                 }
58.  
59.                 float4 Fragment(Varyings i) : SV_Target
60.                 {
61.                     uint2 pixelCoords = i.uv * _ScreenSize.xy;
62.  
63.                     half4 col = LOAD_TEXTURE2D_X(_MainTex, pixelCoords);
64.                     return col;
65.  
66.  
67.                 }
68.  
69.                 ENDHLSL
70.             }
71.         }
72. }

I don't need TextureArrays in my PostProcessing in the first place, because it's not a VR project. But i can't just pass a RenderTexture from custom PostProcessing now. It's RTHandle object with Texture2DArray inside. What am i doing wrong and where to look? It's very frustrating! Is there a way to pass just one screen source texture in the post processing shader like it used to be?

 

@Lynxed: If you compare how that TEXTURE2D_X is used in the HDRP, I think it's not like it's a value type but a method, so you pass that texture as a parameter, like this:

Code (CSharp):

1. TEXTURE2D_X(_InputTexture);

Did you try to cut'n'paste old Post-processing Stack v2 thing and make it work? It looks like that at the moment, as there's quite a few things wrong.

That method called Vertex that takes the Varyings struct in is your vertex program, but you also got that that old style looking vert there?

And quite a few other things that look like they're a bit sideways to my eye.

 

Thank you! I feel so dumb i did not see it's a method!

 

The keywords issue was a problem in my code.
I have submitted a bug report about the namespace issue to unity, and they have sait that they can reproduce, so hopefully it will be rectified soon.

 

I'm trying to get world position from depth, learning from this https://github.com/keijiro/DepthInverseProjection
Non of that code is working out of the box in 2019.3. I made the legacy pr works in this example by replacing paths:

#include "PostProcessing/Shaders/StdLib.hlsl"
to the following:
#include "Packages/com.unity.postprocessing/PostProcessing/Shaders/StdLib.hlsl"

For HDRP custom post process, as @stu_pidd_cow said, i replaced unity_CameraInvProjection with _InvProjMatrix, but i'm getting absolutely different results.

I'm trying to get this (worldPos.xz visualuzed, legacy RP):


but with HDRP i get this:


notice, how axis weirdly rotates with the camera.

My Custom PostProcess Render method looks like this:

Code (CSharp):

1.     public override void Render(CommandBuffer cmd, HDCamera camera, RTHandle source, RTHandle destination)
2.     {
3.         if (m_Material == null)
4.             return;
5.    
6.         m_Material.SetTexture("_MainTex", source);
7.         m_Material.SetFloat("_Opacity", intensity.value);
8.         m_Material.SetMatrix("_InverseView", camera.camera.cameraToWorldMatrix);
9.         m_Material.EnableKeyword("EXCLUDE_FAR_PLANE");
10.         HDUtils.DrawFullScreen(cmd, m_Material, destination, shaderPassId: 1);
11.     }

It's pretty much a copy of what keijiro is doing in hos PPSv2 version of this, so nothing different here.
Can someone please help?

 

So, if i understand correctly, unity_CameraInvProjection is NOT _InvProjMatrix,
Right now I had to make my own with

Code (CSharp):

1. m_Material.SetMatrix("_InvCamProjMatrix", camera.camera.projectionMatrix.inverse);  

that i set every time in post process Render() method.
Now it's working, but i'm sure HDRP has this matrix somewhere.

 

Are you using absolute world space? In HDRP the rendering is camera relative.

 

Didn't know that was a thing. Thank you, i'll dig about this more.

 

Some more things that I have found. Once again, I'm not sure if these are bugs or if they are intentional, but they are definitely not documented anywhere.

• unity_CameraInvProjection no longer exists. It seems like _InvProjMatrix is meant to be the replacement but, whatever is in it, it seems to be wrong. If you pass in your own matrix using camera.projectionMatrix.inverse you will get a very different (yet correct) value.
  
• unity_OrthoParams.xy does not give the same values that it once did. You can get the correct values by doing unity_OrthoParams.xy / 2.

I have finally got my shader to do what I want, but I would like to express how pathetic it has been unity would release HDRP as an "out of preview" package, claiming that custom shaders and custom post processing is now supported, when it is very obvious that it is quite the opposite. A feature does not exist without proper documentation. The official documentation should not consist of telling developers to just "look through the code". There are thousands of lines of code over dozens of source files. And, as I have demonstrated in this thread, the features are either buggy, inconsistent and/or misleading. As an asset store publisher, this has been a nightmarish scenario that has cost me far too much time and has even cost me money in asset sales and negative reviews. As a developer with well over 10 years experience, I have never witnessed such nonexistant support from a large company such as unity. I'm not sure how sustainable this is for unity, but this is not sustainable for me as an asset publisher.

Now I'm moving onto to URP, which has been out of preview for almost a year now, and has just dropped support for the PPSv2 without providing any alternative for custom PP. How much worse can it get, right? /rant