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diff --git a/source/blender/draw/engines/eevee_next/eevee_sampling.hh b/source/blender/draw/engines/eevee_next/eevee_sampling.hh
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index 00000000000..11daa21629a
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+++ b/source/blender/draw/engines/eevee_next/eevee_sampling.hh
@@ -0,0 +1,172 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2021 Blender Foundation.
+ */
+
+/** \file
+ * \ingroup eevee
+ *
+ * Random number generator, contains persistent state and sample count logic.
+ */
+
+#pragma once
+
+#include "BKE_colortools.h"
+#include "BLI_system.h"
+#include "BLI_vector.hh"
+#include "DNA_scene_types.h"
+#include "DRW_render.h"
+
+#include "eevee_shader_shared.hh"
+
+namespace blender::eevee {
+
+class Instance;
+
+class Sampling {
+ private:
+  Instance &inst_;
+
+  /* Number of samples in the first ring of jittered depth of field. */
+  constexpr static uint64_t dof_web_density_ = 6;
+  /* High number of sample for viewport infinite rendering. */
+  constexpr static uint64_t infinite_sample_count_ = 0xFFFFFFu;
+  /* During interactive rendering, loop over the first few samples. */
+  constexpr static uint64_t interactive_sample_max_ = 8;
+
+  /** 0 based current sample. */
+  uint64_t sample_ = 0;
+  /** Target sample count. */
+  uint64_t sample_count_ = 64;
+  /** Number of ring in the web pattern of the jittered Depth of Field. */
+  uint64_t dof_ring_count_ = 0;
+  /** Number of samples in the web pattern of the jittered Depth of Field. */
+  uint64_t dof_sample_count_ = 1;
+  /** Motion blur steps. */
+  uint64_t motion_blur_steps_ = 1;
+  /** Increases if the view and the scene is static. */
+  int64_t viewport_sample_ = 0;
+  /** Tag to reset sampling for the next sample. */
+  bool reset_ = false;
+  /**
+   * Switch between interactive and static accumulation.
+   * In interactive mode, image stability is prioritized over quality.
+   */
+  bool interactive_mode_ = false;
+
+  SamplingDataBuf data_;
+
+ public:
+  Sampling(Instance &inst) : inst_(inst){};
+  ~Sampling(){};
+
+  void init(const Scene *scene);
+  void end_sync();
+  void step();
+
+  /* Viewport Only: Function to call to notify something in the scene changed.
+   * This will reset accumulation. Do not call after end_sync() or during sample rendering. */
+  void reset()
+  {
+    reset_ = true;
+  }
+
+  /* Viewport Only: true if an update happened in the scene and accumulation needs reset. */
+  bool is_reset() const
+  {
+    return reset_;
+  }
+
+  void bind_resources(DRWShadingGroup *grp)
+  {
+    DRW_shgroup_storage_block_ref(grp, "sampling_buf", &data_);
+  }
+
+  /* Returns a pseudo random number in [0..1] range. Each dimension are de-correlated. */
+  float rng_get(eSamplingDimension dimension) const
+  {
+    return data_.dimensions[dimension];
+  }
+
+  /* Returns a pseudo random number in [0..1] range. Each dimension are de-correlated. */
+  float2 rng_2d_get(eSamplingDimension starting_dimension) const
+  {
+    return *reinterpret_cast<const float2 *>(&data_.dimensions[starting_dimension]);
+  }
+
+  /* Returns a pseudo random number in [0..1] range. Each dimension are de-correlated. */
+  float3 rng_3d_get(eSamplingDimension starting_dimension) const
+  {
+    return *reinterpret_cast<const float3 *>(&data_.dimensions[starting_dimension]);
+  }
+
+  /* Returns true if rendering has finished. */
+  bool finished() const
+  {
+    return (sample_ >= sample_count_ - 1);
+  }
+
+  /* Returns true if viewport smoothing and sampling has finished. */
+  bool finished_viewport() const
+  {
+    return finished() && (viewport_sample_ >= interactive_sample_max_);
+  }
+
+  /* Return true if we are starting a new motion blur step. We need to run sync again since
+   * depsgraph was updated by MotionBlur::step(). */
+  bool do_render_sync() const
+  {
+    return ((sample_ % (sample_count_ / motion_blur_steps_)) == 0);
+  }
+
+  /**
+   * Special ball distribution:
+   * Point are distributed in a way that when they are orthogonally
+   * projected into any plane, the resulting distribution is (close to)
+   * a uniform disc distribution.
+   * \a rand is 3 random float in the [0..1] range.
+   * Returns point in a ball of radius 1 and centered on the origin.
+   */
+  static float3 sample_ball(const float3 &rand);
+
+  /**
+   * Uniform disc distribution.
+   * \a rand is 2 random float in the [0..1] range.
+   * Returns point in a disk of radius 1 and centered on the origin.
+   */
+  static float2 sample_disk(const float2 &rand);
+
+  /**
+   * Uniform disc distribution using Fibonacci spiral sampling.
+   * \a rand is 2 random float in the [0..1] range.
+   * Returns point in a disk of radius 1 and centered on the origin.
+   */
+  static float2 sample_spiral(const float2 &rand);
+
+  /**
+   * Special RNG for depth of field.
+   * Returns \a radius and \a theta angle offset to apply to the web sampling pattern.
+   */
+  void dof_disk_sample_get(float *r_radius, float *r_theta) const;
+
+  /**
+   * Returns sample count inside the jittered depth of field web pattern.
+   */
+  uint64_t dof_ring_count_get() const
+  {
+    return dof_ring_count_;
+  }
+
+  /**
+   * Returns sample count inside the jittered depth of field web pattern.
+   */
+  uint64_t dof_sample_count_get() const
+  {
+    return dof_sample_count_;
+  }
+
+  /* Cumulative Distribution Function Utils. */
+  static void cdf_from_curvemapping(const CurveMapping &curve, Vector<float> &cdf);
+  static void cdf_invert(Vector<float> &cdf, Vector<float> &inverted_cdf);
+};
+
+}  // namespace blender::eevee