How can I render negative values into a RenderTexture?

[Linvst]

I used Graphics.DrawMeshInstanced with my custom shader to draw meshes into a camera with a rendertexture attached to it. The renderTexture is in linear space and RFloat format.
I then use texture2d.ReadPixels and GetRawTextureData to get values form the rendertexture. And negative values are clamped to 0 while positive values keep unchanged.

I’ve tried method in this:

[SOLVED] Camera not rendering negative values to render texture

[Edit] Solution: Go to the camera that is drawing to the render texture, enable custom frame settings and turn "Postprocess" off under the Rendering foldout. This is only a problem in HDRP because post processing is disabled by default and I guess it doesn't allow negative values. I'm trying to render particles with positive and negative colors to a render texture for 2d displacement but the render texture appears to only receive or store positive values.The shader used by the particle syst…

but it doesn’t work.

here is my code reading values from the

     void Update()
    {
        var texReadback = new Texture2D(rt.width, rt.height, TextureFormat.RFloat, false, true);
        Graphics.SetRenderTarget(rt);
        texReadback.ReadPixels(new Rect(0, 0, rt.width, rt.height), 0, 0, false);
        Graphics.SetRenderTarget(null);
        texReadback.Apply();

        var data = texReadback.GetRawTextureData<float>();
        for (int i = 0; i < data.Length; i++)
        {
            float t = data[i];
        }
    }

Where is the problem?

[samarth-robo]

The problem is that ReadPixels() does not work with RFloat textures. See documentation and this question/answer.