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diff --git a/source/blender/draw/engines/eevee_next/eevee_light.hh b/source/blender/draw/engines/eevee_next/eevee_light.hh
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+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2021 Blender Foundation.
+ */
+
+/** \file
+ * \ingroup eevee
+ *
+ * The light module manages light data buffers and light culling system.
+ *
+ * The culling follows the principles of Tiled Culling + Z binning from:
+ * "Improved Culling for Tiled and Clustered Rendering"
+ * by Michal Drobot
+ * http://advances.realtimerendering.com/s2017/2017_Sig_Improved_Culling_final.pdf
+ *
+ * The culling is separated in 4 compute phases:
+ * - View Culling (select pass): Create a z distance and a index buffer of visible lights.
+ * - Light sorting: Outputs visible lights sorted by Z distance.
+ * - Z binning: Compute the Z bins min/max light indices.
+ * - Tile intersection: Fine grained 2D culling of each lights outputting a bitmap per tile.
+ */
+
+#pragma once
+
+#include "BLI_bitmap.h"
+#include "BLI_vector.hh"
+#include "DNA_light_types.h"
+
+#include "eevee_camera.hh"
+#include "eevee_sampling.hh"
+#include "eevee_shader.hh"
+#include "eevee_shader_shared.hh"
+#include "eevee_sync.hh"
+
+namespace blender::eevee {
+
+class Instance;
+
+/* -------------------------------------------------------------------- */
+/** \name Light Object
+ * \{ */
+
+struct Light : public LightData {
+ public:
+  bool initialized = false;
+  bool used = false;
+
+ public:
+  Light()
+  {
+    shadow_id = LIGHT_NO_SHADOW;
+  }
+
+  void sync(/* ShadowModule &shadows, */ const Object *ob, float threshold);
+
+  // void shadow_discard_safe(ShadowModule &shadows);
+
+  void debug_draw();
+
+ private:
+  float attenuation_radius_get(const ::Light *la, float light_threshold, float light_power);
+  void shape_parameters_set(const ::Light *la, const float scale[3]);
+  float shape_power_get(const ::Light *la);
+  float point_power_get(const ::Light *la);
+};
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name LightModule
+ * \{ */
+
+/**
+ * The light module manages light data buffers and light culling system.
+ */
+class LightModule {
+  // friend ShadowModule;
+
+ private:
+  /* Keep tile count reasonable for memory usage and 2D culling performance. */
+  static constexpr uint max_memory_threshold = 32 * 1024 * 1024; /* 32 MiB */
+  static constexpr uint max_word_count_threshold = max_memory_threshold / sizeof(uint);
+  static constexpr uint max_tile_count_threshold = 8192;
+
+  Instance &inst_;
+
+  /** Map of light objects data. Converted to flat array each frame. */
+  Map<ObjectKey, Light> light_map_;
+  /** Flat array sent to GPU, populated from light_map_. Source buffer for light culling. */
+  LightDataBuf light_buf_ = {"Lights_no_cull"};
+  /** Recorded size of light_map_ (after pruning) to detect deletion. */
+  int64_t light_map_size_ = 0;
+  /** Luminous intensity to consider the light boundary at. Used for culling. */
+  float light_threshold_ = 0.01f;
+  /** If false, will prevent all scene light from being synced. */
+  bool use_scene_lights_ = false;
+  /** Number of sun lights synced during the last sync. Used as offset. */
+  int sun_lights_len_ = 0;
+  int local_lights_len_ = 0;
+  /** Sun plus local lights count for convenience. */
+  int lights_len_ = 0;
+
+  /**
+   * Light Culling
+   */
+
+  /** LightData buffer used for rendering. Filled by the culling pass. */
+  LightDataBuf culling_light_buf_ = {"Lights_culled"};
+  /** Culling infos. */
+  LightCullingDataBuf culling_data_buf_ = {"LightCull_data"};
+  /** Z-distance matching the key for each visible lights. Used for sorting. */
+  LightCullingZdistBuf culling_zdist_buf_ = {"LightCull_zdist"};
+  /** Key buffer containing only visible lights indices. Used for sorting. */
+  LightCullingKeyBuf culling_key_buf_ = {"LightCull_key"};
+  /** Zbins containing min and max light index for each Z bin. */
+  LightCullingZbinBuf culling_zbin_buf_ = {"LightCull_zbin"};
+  /** Bitmap of lights touching each tiles. */
+  LightCullingTileBuf culling_tile_buf_ = {"LightCull_tile"};
+  /** Culling compute passes. */
+  PassSimple culling_ps_ = {"LightCulling"};
+  /** Total number of words the tile buffer needs to contain for the render resolution. */
+  uint total_word_count_ = 0;
+
+  /** Debug Culling visualization. */
+  PassSimple debug_draw_ps_ = {"LightCulling.Debug"};
+
+ public:
+  LightModule(Instance &inst) : inst_(inst){};
+  ~LightModule(){};
+
+  void begin_sync();
+  void sync_light(const Object *ob, ObjectHandle &handle);
+  void end_sync();
+
+  /**
+   * Update acceleration structure for the given view.
+   */
+  void set_view(View &view, const int2 extent);
+
+  void debug_draw(View &view, GPUFrameBuffer *view_fb);
+
+  void bind_resources(DRWShadingGroup *grp)
+  {
+    DRW_shgroup_storage_block_ref(grp, "light_buf", &culling_light_buf_);
+    DRW_shgroup_storage_block_ref(grp, "light_cull_buf", &culling_data_buf_);
+    DRW_shgroup_storage_block_ref(grp, "light_zbin_buf", &culling_zbin_buf_);
+    DRW_shgroup_storage_block_ref(grp, "light_tile_buf", &culling_tile_buf_);
+#if 0
+    DRW_shgroup_uniform_texture(grp, "shadow_atlas_tx", inst_.shadows.atlas_tx_get());
+    DRW_shgroup_uniform_texture(grp, "shadow_tilemaps_tx", inst_.shadows.tilemap_tx_get());
+#endif
+  }
+
+  template<typename T> void bind_resources(draw::detail::PassBase<T> *pass)
+  {
+    /* Storage Buf. */
+    pass->bind_ssbo(LIGHT_CULL_BUF_SLOT, &culling_data_buf_);
+    pass->bind_ssbo(LIGHT_BUF_SLOT, &culling_light_buf_);
+    pass->bind_ssbo(LIGHT_ZBIN_BUF_SLOT, &culling_zbin_buf_);
+    pass->bind_ssbo(LIGHT_TILE_BUF_SLOT, &culling_tile_buf_);
+  }
+
+ private:
+  void culling_pass_sync();
+  void debug_pass_sync();
+};
+
+/** \} */
+
+}  // namespace blender::eevee