source/blender/blenkernel/BKE_subdiv_eval.hh

   1 /* SPDX-FileCopyrightText: 2018 Blender Authors
   2  *
   3  * SPDX-License-Identifier: GPL-2.0-or-later */
   4
   5 /** \file
   6  * \ingroup bke
   7  */
   8
   9 #pragma once
  10
  11 #include "BLI_math_vector_types.hh"
  12 #include "BLI_span.hh"
  13
  14 struct Mesh;
  15 struct OpenSubdiv_EvaluatorCache;
  16 struct OpenSubdiv_EvaluatorSettings;
  17
  18 namespace blender::bke::subdiv {
  19
  20 struct Subdiv;
  21
  22 enum eSubdivEvaluatorType {
  23   SUBDIV_EVALUATOR_TYPE_CPU,
  24   SUBDIV_EVALUATOR_TYPE_GPU,
  25 };
  26
  27 /* Returns true if evaluator is ready for use. */
  28 bool eval_begin(Subdiv *subdiv,
  29                 eSubdivEvaluatorType evaluator_type,
  30                 OpenSubdiv_EvaluatorCache *evaluator_cache,
  31                 const OpenSubdiv_EvaluatorSettings *settings);
  32
  33 /* coarse_vertex_cos is an optional argument which allows to override coordinates of the coarse
  34  * mesh. */
  35 bool eval_begin_from_mesh(Subdiv *subdiv,
  36                           const Mesh *mesh,
  37                           Span<float3> coarse_vert_positions,
  38                           eSubdivEvaluatorType evaluator_type,
  39                           OpenSubdiv_EvaluatorCache *evaluator_cache);
  40 bool eval_refine_from_mesh(Subdiv *subdiv, const Mesh *mesh, Span<float3> coarse_vert_positions);
  41
  42 /* Makes sure displacement evaluator is initialized.
  43  *
  44  * NOTE: This function must be called once before evaluating displacement or
  45  * final surface position. */
  46 void eval_init_displacement(Subdiv *subdiv);
  47
  48 /* Single point queries. */
  49
  50 /* Evaluate point at a limit surface, with optional derivatives and normal. */
  51
  52 void eval_limit_point(Subdiv *subdiv, int ptex_face_index, float u, float v, float r_P[3]);
  53 void eval_limit_point_and_derivatives(Subdiv *subdiv,
  54                                       int ptex_face_index,
  55                                       float u,
  56                                       float v,
  57                                       float r_P[3],
  58                                       float r_dPdu[3],
  59                                       float r_dPdv[3]);
  60 void eval_limit_point_and_normal(
  61     Subdiv *subdiv, int ptex_face_index, float u, float v, float r_P[3], float r_N[3]);
  62
  63 /* Evaluate smoothly interpolated vertex data (such as ORCO). */
  64 void eval_vertex_data(Subdiv *subdiv,
  65                       const int ptex_face_index,
  66                       const float u,
  67                       const float v,
  68                       float r_vertex_data[]);
  69
  70 /* Evaluate face-varying layer (such as UV). */
  71 void eval_face_varying(Subdiv *subdiv,
  72                        int face_varying_channel,
  73                        int ptex_face_index,
  74                        float u,
  75                        float v,
  76                        float r_face_varying[2]);
  77
  78 /* NOTE: Expects derivatives to be correct.
  79  *
  80  * TODO(sergey): This is currently used together with
  81  * eval_final_point() which can easily evaluate derivatives.
  82  * Would be nice to have displacement evaluation function which does not require
  83  * knowing derivatives ahead of a time. */
  84 void eval_displacement(Subdiv *subdiv,
  85                        int ptex_face_index,
  86                        float u,
  87                        float v,
  88                        const float dPdu[3],
  89                        const float dPdv[3],
  90                        float r_D[3]);
  91
  92 /* Evaluate point on a limit surface with displacement applied to it. */
  93 void eval_final_point(Subdiv *subdiv, int ptex_face_index, float u, float v, float r_P[3]);
  94
  95 }  // namespace blender::bke::subdiv