Files
test/source/blender/blenkernel/BKE_subdiv_eval.hh
2025-08-24 16:19:48 +10:00

98 lines
3.2 KiB
C++

/* SPDX-FileCopyrightText: 2018 Blender Authors
*
* SPDX-License-Identifier: GPL-2.0-or-later */
/** \file
* \ingroup bke
*/
#pragma once
#include "BLI_math_vector_types.hh"
#include "BLI_span.hh"
struct Mesh;
struct OpenSubdiv_EvaluatorCache;
struct OpenSubdiv_EvaluatorSettings;
namespace blender::bke::subdiv {
struct Subdiv;
enum eSubdivEvaluatorType {
SUBDIV_EVALUATOR_TYPE_CPU,
SUBDIV_EVALUATOR_TYPE_GPU,
};
/** Returns true if evaluator is ready for use. */
bool eval_begin(Subdiv *subdiv,
eSubdivEvaluatorType evaluator_type,
OpenSubdiv_EvaluatorCache *evaluator_cache,
const OpenSubdiv_EvaluatorSettings *settings);
/**
* \param coarse_vert_positions: optional span of positions to override the mesh positions.
*/
bool eval_begin_from_mesh(Subdiv *subdiv,
const Mesh *mesh,
eSubdivEvaluatorType evaluator_type,
Span<float3> coarse_vert_positions = {},
OpenSubdiv_EvaluatorCache *evaluator_cache = nullptr);
bool eval_refine_from_mesh(Subdiv *subdiv, const Mesh *mesh, Span<float3> coarse_vert_positions);
/**
* Makes sure displacement evaluator is initialized.
*
* \note This function must be called once before evaluating displacement or
* final surface position.
*/
void eval_init_displacement(Subdiv *subdiv);
/* Single point queries. */
/* Evaluate point at a limit surface, with optional derivatives and normal. */
float3 eval_limit_point(Subdiv *subdiv, int ptex_face_index, float u, float v);
void eval_limit_point_and_derivatives(Subdiv *subdiv,
int ptex_face_index,
float u,
float v,
float3 &r_P,
float3 &r_dPdu,
float3 &r_dPdv);
void eval_limit_point_and_normal(
Subdiv *subdiv, int ptex_face_index, float u, float v, float3 &r_P, float3 &r_N);
/** Evaluate smoothly interpolated vertex data (such as ORCO). */
void eval_vertex_data(
Subdiv *subdiv, int ptex_face_index, float u, float v, float r_vertex_data[]);
/** Evaluate face-varying layer (such as UV). */
void eval_face_varying(Subdiv *subdiv,
int face_varying_channel,
int ptex_face_index,
float u,
float v,
float2 &r_face_varying);
/**
* \note Expects derivatives to be correct.
*
* TODO(sergey): This is currently used together with
* eval_final_point() which can easily evaluate derivatives.
* Would be nice to have displacement evaluation function which does not require
* knowing derivatives ahead of a time.
*/
void eval_displacement(Subdiv *subdiv,
int ptex_face_index,
float u,
float v,
const float3 &dPdu,
const float3 &dPdv,
float3 &r_D);
/** Evaluate point on a limit surface with displacement applied to it. */
float3 eval_final_point(Subdiv *subdiv, int ptex_face_index, float u, float v);
} // namespace blender::bke::subdiv