/* SPDX-License-Identifier: GPL-2.0-or-later
 * Copyright 2005 Blender Foundation. All rights reserved. */

/** \file
 * \ingroup gpu
 */

#pragma once

#include <stddef.h>

#ifdef __cplusplus
extern "C" {
#endif

struct BMesh;
struct CCGElem;
struct CCGKey;
struct DMFlagMat;
struct GSet;
struct MLoop;
struct MLoopCol;
struct MLoopTri;
struct MPoly;
struct MPropCol;
struct MVert;
struct Mesh;
struct PBVH;
struct SubdivCCG;

/**
 * Buffers for drawing from PBVH grids.
 */
typedef struct GPU_PBVH_Buffers GPU_PBVH_Buffers;

/**
 * Build must be called once before using the other functions,
 * used every time mesh topology changes.
 *
 * Threaded: do not call any functions that use OpenGL calls!
 */
GPU_PBVH_Buffers *GPU_pbvh_mesh_buffers_build(const struct MPoly *mpoly,
                                              const struct MLoop *mloop,
                                              const struct MLoopTri *looptri,
                                              const struct MVert *mvert,
                                              const int *face_indices,
                                              const int *sculpt_face_sets,
                                              int face_indices_len,
                                              const struct Mesh *mesh);

/**
 * Threaded: do not call any functions that use OpenGL calls!
 */
GPU_PBVH_Buffers *GPU_pbvh_grid_buffers_build(int totgrid, unsigned int **grid_hidden);

/**
 * Threaded: do not call any functions that use OpenGL calls!
 */
GPU_PBVH_Buffers *GPU_pbvh_bmesh_buffers_build(bool smooth_shading);

/**
 * Free part of data for update. Not thread safe, must run in OpenGL main thread.
 */
void GPU_pbvh_bmesh_buffers_update_free(GPU_PBVH_Buffers *buffers);
void GPU_pbvh_grid_buffers_update_free(GPU_PBVH_Buffers *buffers,
                                       const struct DMFlagMat *grid_flag_mats,
                                       const int *grid_indices);

/**
 * Update mesh buffers without topology changes. Threaded.
 */
enum {
  GPU_PBVH_BUFFERS_SHOW_MASK = (1 << 1),
  GPU_PBVH_BUFFERS_SHOW_VCOL = (1 << 2),
  GPU_PBVH_BUFFERS_SHOW_SCULPT_FACE_SETS = (1 << 3),
};

/**
 * Threaded: do not call any functions that use OpenGL calls!
 */
void GPU_pbvh_mesh_buffers_update(GPU_PBVH_Buffers *buffers,
                                  const struct MVert *mvert,
                                  const float (*vert_normals)[3],
                                  const float *vmask,
                                  const struct MLoopCol *vcol,
                                  const int *sculpt_face_sets,
                                  int face_sets_color_seed,
                                  int face_sets_color_default,
                                  const struct MPropCol *vtcol,
                                  int update_flags);

/**
 * Creates a vertex buffer (coordinate, normal, color) and,
 * if smooth shading, an element index buffer.
 * Threaded: do not call any functions that use OpenGL calls!
 */
void GPU_pbvh_bmesh_buffers_update(GPU_PBVH_Buffers *buffers,
                                   struct BMesh *bm,
                                   struct GSet *bm_faces,
                                   struct GSet *bm_unique_verts,
                                   struct GSet *bm_other_verts,
                                   int update_flags);

/**
 * Threaded: do not call any functions that use OpenGL calls!
 */
void GPU_pbvh_grid_buffers_update(GPU_PBVH_Buffers *buffers,
                                  struct SubdivCCG *subdiv_ccg,
                                  struct CCGElem **grids,
                                  const struct DMFlagMat *grid_flag_mats,
                                  int *grid_indices,
                                  int totgrid,
                                  const int *sculpt_face_sets,
                                  int face_sets_color_seed,
                                  int face_sets_color_default,
                                  const struct CCGKey *key,
                                  int update_flags);

/**
 * Finish update. Not thread safe, must run in OpenGL main thread.
 */
void GPU_pbvh_buffers_update_flush(GPU_PBVH_Buffers *buffers);

/**
 * Free buffers. Not thread safe, must run in OpenGL main thread.
 */
void GPU_pbvh_buffers_free(GPU_PBVH_Buffers *buffers);

/** Draw. */
struct GPUBatch *GPU_pbvh_buffers_batch_get(GPU_PBVH_Buffers *buffers, bool fast, bool wires);

short GPU_pbvh_buffers_material_index_get(GPU_PBVH_Buffers *buffers);

bool GPU_pbvh_buffers_has_overlays(GPU_PBVH_Buffers *buffers);

#ifdef __cplusplus
}
#endif