Matrix4x4 GetJitteredProjectionMatrix(Matrix4x4 origProj)
{
// The variance between 0 and the actual halton sequence values reveals noticeable
// instability in Unity's shadow maps, so we avoid index 0.
float jitterX = HaltonSequence.Get((taaFrameIndex & 1023) + 1, 2) - 0.5f;
float jitterY = HaltonSequence.Get((taaFrameIndex & 1023) + 1, 3) - 0.5f;
taaJitter = new Vector4(jitterX, jitterY, jitterX / camera.pixelWidth, jitterY / camera.pixelHeight);
const int kMaxSampleCount = 8;
if (++taaFrameIndex >= kMaxSampleCount)
{
taaFrameIndex = 0;
}
Matrix4x4 proj;
if (camera.orthographic)
{
float vertical = camera.orthographicSize;
float horizontal = vertical * camera.aspect;
var offset = taaJitter;
offset.x *= horizontal / (0.5f * camera.pixelWidth);
offset.y *= vertical / (0.5f * camera.pixelHeight);
float left = offset.x - horizontal;
float right = offset.x + horizontal;
float top = offset.y + vertical;
float bottom = offset.y - vertical;
proj = Matrix4x4.Ortho(left, right, bottom, top, camera.nearClipPlane, camera.farClipPlane);
}
else
{
var planes = origProj.decomposeProjection;
float vertFov = Math.Abs(planes.top) + Math.Abs(planes.bottom);
float horizFov = Math.Abs(planes.left) + Math.Abs(planes.right);
var planeJitter = new Vector2(jitterX * horizFov / camera.pixelWidth,
jitterY * vertFov / camera.pixelHeight);
planes.left += planeJitter.x;
planes.right += planeJitter.x;
planes.top += planeJitter.y;
planes.bottom += planeJitter.y;
proj = Matrix4x4.Frustum(planes);
}
return(proj);
}
public Vector2 Sample(Vector2 maximum, Vector2 minimum = default)
{
var offset = minimum;
var scale = maximum - minimum;
var sample = new Vector2(
HaltonSequence.Get(indexInSequence, horizontalRadix),
HaltonSequence.Get(indexInSequence, verticalRadix)
);
indexInSequence++;
return((sample * scale) + offset);
}
private Matrix4x4 GetJitteredProjectionMatrix(Matrix4x4 origProj, Camera UnityCamera)
{
float jitterX = HaltonSequence.Get((FrameIndex & 1023) + 1, 2) - 0.5f;
float jitterY = HaltonSequence.Get((FrameIndex & 1023) + 1, 3) - 0.5f;
TAAJitter = new float2(jitterX, jitterY);
float4 taaJitter = new float4(jitterX, jitterY, jitterX / UnityCamera.pixelRect.size.x, jitterY / UnityCamera.pixelRect.size.y);
if (++FrameIndex >= 8)
{
FrameIndex = 0;
}
Matrix4x4 proj;
if (UnityCamera.orthographic)
{
float vertical = UnityCamera.orthographicSize;
float horizontal = vertical * UnityCamera.aspect;
var offset = taaJitter;
offset.x *= horizontal / (0.5f * UnityCamera.pixelRect.size.x);
offset.y *= vertical / (0.5f * UnityCamera.pixelRect.size.y);
float left = offset.x - horizontal;
float right = offset.x + horizontal;
float top = offset.y + vertical;
float bottom = offset.y - vertical;
proj = Matrix4x4.Ortho(left, right, bottom, top, UnityCamera.nearClipPlane, UnityCamera.farClipPlane);
}
else
{
var planes = origProj.decomposeProjection;
float vertFov = Math.Abs(planes.top) + Math.Abs(planes.bottom);
float horizFov = Math.Abs(planes.left) + Math.Abs(planes.right);
var planeJitter = new Vector2(jitterX * horizFov / UnityCamera.pixelRect.size.x, jitterY * vertFov / UnityCamera.pixelRect.size.y);
planes.left += planeJitter.x;
planes.right += planeJitter.x;
planes.top += planeJitter.y;
planes.bottom += planeJitter.y;
proj = Matrix4x4.Frustum(planes);
}
return(proj);
}