using UnityEngine.Rendering;
namespace UnityEngine.Experimental.Rendering
{
/// <summary>
/// Helper static class used by render pipelines to setup stereo constants accessed by builtin shaders.
/// </summary>
public static class XRBuiltinShaderConstants
{
/// <summary>
/// Cached unique id for unity_StereoCameraProjection
/// </summary>
static public readonly int unity_StereoCameraProjection = Shader.PropertyToID("unity_StereoCameraProjection");
/// <summary>
/// Cached unique id for unity_StereoCameraInvProjection
/// </summary>
static public readonly int unity_StereoCameraInvProjection = Shader.PropertyToID("unity_StereoCameraInvProjection");
/// <summary>
/// Cached unique id for unity_StereoMatrixV
/// </summary>
static public readonly int unity_StereoMatrixV = Shader.PropertyToID("unity_StereoMatrixV");
/// <summary>
/// Cached unique id for unity_StereoMatrixInvV
/// </summary>
static public readonly int unity_StereoMatrixInvV = Shader.PropertyToID("unity_StereoMatrixInvV");
/// <summary>
/// Cached unique id for unity_StereoMatrixP
/// </summary>
static public readonly int unity_StereoMatrixP = Shader.PropertyToID("unity_StereoMatrixP");
/// <summary>
/// Cached unique id for unity_StereoMatrixInvP
/// </summary>
static public readonly int unity_StereoMatrixInvP = Shader.PropertyToID("unity_StereoMatrixInvP");
/// <summary>
/// Cached unique id for unity_StereoMatrixVP
/// </summary>
static public readonly int unity_StereoMatrixVP = Shader.PropertyToID("unity_StereoMatrixVP");
/// <summary>
/// Cached unique id for unity_StereoMatrixInvVP
/// </summary>
static public readonly int unity_StereoMatrixInvVP = Shader.PropertyToID("unity_StereoMatrixInvVP");
/// <summary>
/// Cached unique id for unity_StereoWorldSpaceCameraPos
/// </summary>
static public readonly int unity_StereoWorldSpaceCameraPos = Shader.PropertyToID("unity_StereoWorldSpaceCameraPos");
/// <summary>
/// Cached unique id for unity_StereoEyeIndex
/// </summary>
static public readonly int unity_StereoEyeIndex = Shader.PropertyToID("unity_StereoEyeIndex");
// Pre-allocate arrays to avoid GC
static Matrix4x4[] s_cameraProjMatrix = new Matrix4x4[2];
static Matrix4x4[] s_invCameraProjMatrix = new Matrix4x4[2];
static Matrix4x4[] s_viewMatrix = new Matrix4x4[2];
static Matrix4x4[] s_invViewMatrix = new Matrix4x4[2];
static Matrix4x4[] s_projMatrix = new Matrix4x4[2];
static Matrix4x4[] s_invProjMatrix = new Matrix4x4[2];
static Matrix4x4[] s_viewProjMatrix = new Matrix4x4[2];
static Matrix4x4[] s_invViewProjMatrix = new Matrix4x4[2];
static Vector4[] s_worldSpaceCameraPos = new Vector4[2];
/// <summary>
/// Update the shader constant data used by the C++ builtin renderer.
/// </summary>
/// <param name="viewMatrix"> The new view matrix that XR shaders constant should update to use. </param>
/// <param name="projMatrix"> The new projection matrix that XR shaders constant should update to use. </param>
/// <param name="renderIntoTexture"> Determines the yflip state for the projection matrix. </param>
/// <param name="viewIndex"> Index of the XR shader constant to update. </param>
public static void UpdateBuiltinShaderConstants(Matrix4x4 viewMatrix, Matrix4x4 projMatrix, bool renderIntoTexture, int viewIndex)
{
#if ENABLE_VR && ENABLE_XR_MODULE
var gpuProjMatrix = GL.GetGPUProjectionMatrix(projMatrix, renderIntoTexture);
var gpuViewProjMatrix = gpuProjMatrix * viewMatrix;
s_cameraProjMatrix[viewIndex] = projMatrix;
s_projMatrix[viewIndex] = gpuProjMatrix;
s_viewMatrix[viewIndex] = viewMatrix;
Matrix4x4.Inverse3DAffine(viewMatrix, ref s_invViewMatrix[viewIndex]);
s_viewProjMatrix[viewIndex] = gpuViewProjMatrix;
s_invCameraProjMatrix[viewIndex] = Matrix4x4.Inverse(projMatrix);
s_invProjMatrix[viewIndex] = Matrix4x4.Inverse(gpuProjMatrix);
s_invViewProjMatrix[viewIndex] = Matrix4x4.Inverse(gpuViewProjMatrix);
s_worldSpaceCameraPos[viewIndex] = s_invViewMatrix[viewIndex].GetColumn(3);
#endif
}
/// <summary>
/// Bind the shader constants used by the C++ builtin renderer via a command buffer. `UpdateBuiltinShaderConstants` should be called before to update the constants.
/// This is required to maintain compatibility with legacy code and shaders.
/// </summary>
/// <param name="cmd"> Commandbuffer on which to set XR shader constants. </param>
public static void SetBuiltinShaderConstants(CommandBuffer cmd)
{
#if ENABLE_VR && ENABLE_XR_MODULE
cmd.SetGlobalMatrixArray(unity_StereoCameraProjection, s_cameraProjMatrix);
cmd.SetGlobalMatrixArray(unity_StereoCameraInvProjection, s_invCameraProjMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixV, s_viewMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixInvV, s_invViewMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixP, s_projMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixInvP, s_invProjMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixVP, s_viewProjMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixInvVP, s_invViewProjMatrix);
cmd.SetGlobalVectorArray(unity_StereoWorldSpaceCameraPos, s_worldSpaceCameraPos);
#endif
}
/// <summary>
/// Bind the shader constants used by the C++ builtin renderer via a raster command buffer. `UpdateBuiltinShaderConstants` should be called before to update the constants.
/// This is required to maintain compatibility with legacy code and shaders.
/// </summary>
/// <param name="cmd"> RasterCommandbuffer on which to set XR shader constants. </param>
public static void SetBuiltinShaderConstants(RasterCommandBuffer cmd)
{
SetBuiltinShaderConstants(cmd.m_WrappedCommandBuffer);
}
/// <summary>
/// Update and bind shader constants used by the C++ builtin renderer given the XRPass. For better control of setting up builtin shader constants, see `UpdateBuiltinShaderConstants`
/// and `SetBuiltinShaderConstants` which do the same logic but could take in custom projection and view matricies instead.
/// This is required to maintain compatibility with legacy code and shaders.
/// </summary>
/// <param name="xrPass"> The new XRPass that XR shader constants should update to use. </param>
/// <param name="cmd"> CommandBuffer on which to set XR shader constants. </param>
/// <param name="renderIntoTexture"> Determines the yflip state for the projection matrix. </param>
public static void Update(XRPass xrPass, CommandBuffer cmd, bool renderIntoTexture)
{
#if ENABLE_VR && ENABLE_XR_MODULE
if (xrPass.enabled)
{
cmd.SetViewProjectionMatrices(xrPass.GetViewMatrix(), xrPass.GetProjMatrix());
if (xrPass.singlePassEnabled)
{
for (int viewIndex = 0; viewIndex < 2; ++viewIndex)
{
s_cameraProjMatrix[viewIndex] = xrPass.GetProjMatrix(viewIndex);
s_viewMatrix[viewIndex] = xrPass.GetViewMatrix(viewIndex);
s_projMatrix[viewIndex] = GL.GetGPUProjectionMatrix(s_cameraProjMatrix[viewIndex], renderIntoTexture);
s_viewProjMatrix[viewIndex] = s_projMatrix[viewIndex] * s_viewMatrix[viewIndex];
s_invCameraProjMatrix[viewIndex] = Matrix4x4.Inverse(s_cameraProjMatrix[viewIndex]);
Matrix4x4.Inverse3DAffine(s_viewMatrix[viewIndex], ref s_invViewMatrix[viewIndex]);
s_invProjMatrix[viewIndex] = Matrix4x4.Inverse(s_projMatrix[viewIndex]);
s_invViewProjMatrix[viewIndex] = Matrix4x4.Inverse(s_viewProjMatrix[viewIndex]);
s_worldSpaceCameraPos[viewIndex] = s_invViewMatrix[viewIndex].GetColumn(3);
}
cmd.SetGlobalMatrixArray(unity_StereoCameraProjection, s_cameraProjMatrix);
cmd.SetGlobalMatrixArray(unity_StereoCameraInvProjection, s_invCameraProjMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixV, s_viewMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixInvV, s_invViewMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixP, s_projMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixInvP, s_invProjMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixVP, s_viewProjMatrix);
cmd.SetGlobalMatrixArray(unity_StereoMatrixInvVP, s_invViewProjMatrix);
cmd.SetGlobalVectorArray(unity_StereoWorldSpaceCameraPos, s_worldSpaceCameraPos);
}
}
#endif
}
}
}