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diff --git a/source/blender/draw/engines/eevee_next/eevee_motion_blur.hh b/source/blender/draw/engines/eevee_next/eevee_motion_blur.hh
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+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2022 Blender Foundation.
+ */
+
+/** \file
+ * \ingroup eevee
+ *
+ * Motion blur is done by accumulating scene samples over shutter time.
+ * Since the number of step is discrete, quite low, and not per pixel randomized,
+ * we couple this with a post processing motion blur.
+ *
+ * The post-fx motion blur is done in two directions, from the previous step and to the next.
+ *
+ * For a scene with 3 motion steps, a flat shutter curve and shutter time of 2 frame
+ * centered on frame we have:
+ *
+ * |--------------------|--------------------|
+ * -1                   0                    1  Frames
+ *
+ * |-------------|-------------|-------------|
+ *        1             2             3         Motion steps
+ *
+ * |------|------|------|------|------|------|
+ * 0      1      2      4      5      6      7  Time Steps
+ *
+ * |-------------| One motion step blurs this range.
+ * -1     |     +1 Objects and geometry steps are recorded here.
+ *        0 Scene is rendered here.
+ *
+ * Since motion step N and N+1 share one time step we reuse it to avoid an extra scene evaluation.
+ *
+ * Note that we have to evaluate -1 and +1 time steps before rendering so eval order is -1, +1, 0.
+ * This is because all GPUBatches from the DRWCache are being free when changing a frame.
+ *
+ * For viewport, we only have the current and previous step data to work with. So we center the
+ * blur on the current frame and extrapolate the motion.
+ *
+ * The Post-FX motion blur is based on:
+ * "A Fast and Stable Feature-Aware Motion Blur Filter"
+ * by Jean-Philippe Guertin, Morgan McGuire, Derek Nowrouzezahrai
+ */
+
+#pragma once
+
+#include "BLI_map.hh"
+#include "DEG_depsgraph_query.h"
+
+#include "eevee_sampling.hh"
+#include "eevee_shader_shared.hh"
+#include "eevee_velocity.hh"
+
+namespace blender::eevee {
+
+/* -------------------------------------------------------------------- */
+/** \name MotionBlur
+ *
+ * \{ */
+
+/**
+ * Manages time-steps evaluations and accumulation Motion blur.
+ * Also handles Post process motion blur.
+ */
+class MotionBlurModule {
+ private:
+  Instance &inst_;
+
+  /**
+   * Array containing all steps (in scene time) we need to evaluate (not render).
+   * Only odd steps are rendered. The even ones are evaluated for fx motion blur.
+   */
+  Vector<float> time_steps_;
+
+  /** Copy of input frame and sub-frame to restore after render. */
+  int initial_frame_;
+  float initial_subframe_;
+  /** Time of the frame we are rendering. */
+  float frame_time_;
+  /** Enum controlling when the shutter opens. See SceneEEVEE.motion_blur_position. */
+  int shutter_position_;
+  /** Time in scene frame the shutter is open. Controls the amount of blur. */
+  float shutter_time_;
+
+  /** True if motion blur is enabled as a module. */
+  bool enabled_ = false;
+  /** True if motion blur post-fx is enabled. */
+  float motion_blur_fx_enabled_ = false;
+  /** True if last viewport redraw state was already in navigation state. */
+  bool was_navigating_ = false;
+
+  int step_id_ = 0;
+
+  /** Velocity tiles used to guide and speedup the gather pass. */
+  TextureFromPool tiles_tx_;
+
+  GPUTexture *input_color_tx_ = nullptr;
+  GPUTexture *output_color_tx_ = nullptr;
+
+  DRWPass *tiles_flatten_ps_ = nullptr;
+  DRWPass *tiles_dilate_ps_ = nullptr;
+  DRWPass *gather_ps_ = nullptr;
+
+  MotionBlurTileIndirectionBuf tile_indirection_buf_;
+  MotionBlurDataBuf data_;
+  /** Dispatch size for full-screen passes. */
+  int3 dispatch_flatten_size_ = int3(0);
+  int3 dispatch_dilate_size_ = int3(0);
+  int3 dispatch_gather_size_ = int3(0);
+
+ public:
+  MotionBlurModule(Instance &inst) : inst_(inst){};
+  ~MotionBlurModule(){};
+
+  void init();
+
+  void step();
+
+  void sync();
+
+  bool postfx_enabled() const
+  {
+    return motion_blur_fx_enabled_;
+  }
+
+  void render(GPUTexture **input_tx, GPUTexture **output_tx);
+
+ private:
+  float shutter_time_to_scene_time(float time);
+};
+
+/** \} */
+
+}  // namespace blender::eevee