Interger return value in shader with R8 R16 RenderTexture

Questions & Answers
1

I am trying to construct a render texture with format R8 our R16 that is integer format. I only need 1 channel for my texture. My shader is very simple :

 Properties
 {
     _ID ("ID", Int) = 1
 } 
 int frag () : SV_Target
 {
     return _ID;
 }

This code doesn’t work and it seems that only float works for the return statement of the fragment shader. How can I use format R8 or R16 ? How can I convert my int to float and them float to int if it’s impossible to store int ?

2

After some test in rederDock, shader is correctly create but I use custom render pass with my camera and VBO seams to be disable for undifned reason.

Here the corerct fragment shader used :

#version 450
#extension GL_ARB_explicit_attrib_location : require
#ifdef GL_ARB_shader_bit_encoding
#extension GL_ARB_shader_bit_encoding : enable
#endif

#define HLSLCC_ENABLE_UNIFORM_BUFFERS 1
#if HLSLCC_ENABLE_UNIFORM_BUFFERS
#define UNITY_UNIFORM
#else
#define UNITY_UNIFORM uniform
#endif
#define UNITY_SUPPORTS_UNIFORM_LOCATION 1
#if UNITY_SUPPORTS_UNIFORM_LOCATION
#define UNITY_LOCATION(x) layout(location = x)
#define UNITY_BINDING(x) layout(binding = x, std140)
#else
#define UNITY_LOCATION(x)
#define UNITY_BINDING(x) layout(std140)
#endif
uniform 	int _ID;
layout(location = 0) out int SV_Target0;
void main()
{
    SV_Target0 = _ID;
    return;
}

Here the disabled VBO :

186440-capture-decran-2021-09-19-193846.png
186440-capture-decran-2021-09-19-193846.png1920×1009 184 KB

So, I will try to create my own render pipeline to avoid this problem (And also because I need to create them for my feature).
However, I’m not sure why it works with float because my VBO is also disabled … maybe undefined behaviour is happening and luckily works with the float instruction … I don’t know

RESOLVE:
If you use camera.Render, you need to wait the end of frame. To do this, you can use coroutine like :

    IEnumerator Start()
    {       
        while (true)
        {
            // Wait until all rendering + UI is done.
            yield return new WaitForEndOfFrame();
           YOUR_RENDER_FUNCTION();
        }
    }