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diff --git a/source/blender/draw/engines/eevee/eevee_hizbuffer.hh b/source/blender/draw/engines/eevee/eevee_hizbuffer.hh
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+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Copyright 2021, Blender Foundation.
+ */
+
+/** \file
+ * \ingroup eevee
+ *
+ * The Hierarchical-Z buffer is texture containing a copy of the depth buffer with mipmaps.
+ * Each mip contains the maximum depth of each 4 pixels on the upper level.
+ * The size of the texture is padded to avoid messing with the mipmap pixels alignments.
+ */
+
+#pragma once
+
+#include "DRW_render.h"
+
+#include "eevee_shader_shared.hh"
+
+namespace blender::eevee {
+
+class Instance;
+
+/* -------------------------------------------------------------------- */
+/** \name Hierarchical-Z buffer
+ * \{ */
+
+class HiZBuffer {
+ private:
+  Instance &inst_;
+  /** Framebuffer use for recursive downsampling. */
+  /* TODO(fclem) Remove this and use a compute shader instead. */
+  Framebuffer hiz_fb_ = Framebuffer("DepthHiz");
+  /** Max mip to downsample to. We ensure the hiz has enough padding to never
+   * have to compensate the mipmap alignments. */
+  constexpr static int mip_count_ = 6;
+  /** TODO/OPTI(fclem): Share it between similar views. */
+  Texture hiz_tx_;
+
+ public:
+  HiZBuffer(Instance &inst) : inst_(inst){};
+
+  void prepare(GPUTexture *depth_src);
+  void update(GPUTexture *depth_src);
+
+  GPUTexture *texture_get(void) const
+  {
+    return hiz_tx_;
+  }
+
+ private:
+  static void recursive_downsample(void *thunk, int lvl);
+};
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Hierarchical-Z buffer Module
+ * \{ */
+
+class HiZBufferModule {
+  friend HiZBuffer;
+
+ private:
+  Instance &inst_;
+
+  HiZDataBuf data_;
+  /** Copy input depth to hiz-buffer with border padding. */
+  DRWPass *hiz_copy_ps_;
+  /** Downsample one mipmap level. */
+  DRWPass *hiz_downsample_ps_;
+  /** References only. */
+  GPUTexture *input_depth_tx_ = nullptr;
+  /** Pixel size of the render target during hiz downsampling. */
+  vec2 texel_size_;
+
+ public:
+  HiZBufferModule(Instance &inst) : inst_(inst){};
+
+  void sync(void);
+
+  const GPUUniformBuf *ubo_get(void) const
+  {
+    return data_.ubo_get();
+  }
+};
+
+/** \} */
+
+}  // namespace blender::eevee