Question Manually calculating shader parameters unity_WorldToShadow, _LightProjectionParams, _LightShadowData

I am trying to DrawRenderer with same lighting as Unity uses. But there's no documentation/posts/tutorials about how to calculate built-in parameters manually (Unity doesn't give an option to set them for you, so it's all up you) such as unity_WorldToShadow[4], _LightProjectionParams, _LightShadowData, _ShadowCenterAndType etc.

Since there's no access to the source code of the built-in render pipeline Unity makes it impossible to make this feature work.

There's has been many posts about this topic but never got proper response. Or ones that's given is just false/obsolete information.

TLDR; Can we finally get an source code of how these parameters has been calculated? Thanks.

 

I've managed to find the calculation for _LightShadowData parameter, but the Z value is still off.

_LightShadowData.x = 1.0 - shadow distance.
_LightShadowData.y = max(camera far clip / shadow distance, 1.0) // but not used in current built-in shader codebase
_LightShadowData.z = 5.0f * max(camera far clip / shadow distance, 1.0) / min(camera far clip, shadow distance) // not sure about the 5.0f, but it seems like the value
_LightShadowData.w = -1.0f * (2.0f + camera field of view / 180.0f * 2.0f) // fov is regarded as 0 when orthographic.

Source: https://forum.unity.com/threads/what-is-in-float4-_lightshadowdata.165718/

 

_LightShadowData.z = 5.0f / min(camera far clip, shadow distance)

Works for 2019.1 version. But still struggling with unity_WorldToShadow matrix. There's isn't a single working information about how it's calculated.

 

I use in

Code (CSharp):

1. void Update()
2. {
3. var world2ShadowMatrix = Shader.GetGlobalMatrix("unity_WorldToShadow");
4. var unity_LightShadowBias = Shader.GetGlobalVector("unity_LightShadowBias");
5. }

But unity_WorldToShadow is not matrtix array, and may be old matrix from last frame;