Files
test2/source/blender/blenkernel/BKE_mesh.hh
2023-05-20 21:17:09 +10:00

343 lines
12 KiB
C++

/* SPDX-License-Identifier: GPL-2.0-or-later */
#pragma once
/** \file
* \ingroup bke
*/
#include "BKE_mesh.h"
namespace blender::bke::mesh {
/* -------------------------------------------------------------------- */
/** \name Polygon Data Evaluation
* \{ */
/** Calculate the up direction for the polygon, depending on its winding direction. */
float3 poly_normal_calc(Span<float3> vert_positions, Span<int> poly_verts);
/**
* Calculate tessellation into #MLoopTri which exist only for this purpose.
*/
void looptris_calc(Span<float3> vert_positions,
OffsetIndices<int> polys,
Span<int> corner_verts,
MutableSpan<MLoopTri> looptris);
/**
* A version of #looptris_calc which takes pre-calculated polygon normals
* (used to avoid having to calculate the face normal for NGON tessellation).
*
* \note Only use this function if normals have already been calculated, there is no need
* to calculate normals just to use this function.
*/
void looptris_calc_with_normals(Span<float3> vert_positions,
OffsetIndices<int> polys,
Span<int> corner_verts,
Span<float3> poly_normals,
MutableSpan<MLoopTri> looptris);
void looptris_calc_poly_indices(OffsetIndices<int> polys, MutableSpan<int> looptri_polys);
/** Calculate the average position of the vertices in the polygon. */
float3 poly_center_calc(Span<float3> vert_positions, Span<int> poly_verts);
/** Calculate the surface area of the polygon described by the indexed vertices. */
float poly_area_calc(Span<float3> vert_positions, Span<int> poly_verts);
/** Calculate the angles at each of the polygons corners. */
void poly_angles_calc(Span<float3> vert_positions,
Span<int> poly_verts,
MutableSpan<float> angles);
/** \} */
/* -------------------------------------------------------------------- */
/** \name Medium-Level Normals Calculation
* \{ */
/**
* Calculate face normals directly into a result array.
*
* \note Usually #Mesh::poly_normals() is the preferred way to access face normals,
* since they may already be calculated and cached on the mesh.
*/
void normals_calc_polys(Span<float3> vert_positions,
OffsetIndices<int> polys,
Span<int> corner_verts,
MutableSpan<float3> poly_normals);
/**
* Calculate face and vertex normals directly into result arrays.
*
* \note Usually #Mesh::vert_normals() is the preferred way to access vertex normals,
* since they may already be calculated and cached on the mesh.
*/
void normals_calc_poly_vert(Span<float3> vert_positions,
OffsetIndices<int> polys,
Span<int> corner_verts,
MutableSpan<float3> poly_normals,
MutableSpan<float3> vert_normals);
/** \} */
/* -------------------------------------------------------------------- */
/** \name Face Corner Normal Calculation
* \{ */
/**
* Combined with the automatically calculated face corner normal, this gives a dimensional
* coordinate space used to convert normals between the "custom normal" #short2 representation and
* a regular #float3 format.
*/
struct CornerNormalSpace {
/** Reference vector, orthogonal to corner normal. */
float3 vec_ref;
/** Third vector, orthogonal to corner normal and #vec_ref. */
float3 vec_ortho;
/** Reference angle around #vec_ortho, in [0, pi] range (0.0 marks space as invalid). */
float ref_alpha;
/** Reference angle around corner normal, in [0, 2pi] range (0.0 marks space as invalid). */
float ref_beta;
};
/**
* Storage for corner fan coordinate spaces for an entire mesh.
*/
struct CornerNormalSpaceArray {
/**
* The normal coordinate spaces, potentially shared between multiple face corners in a smooth fan
* connected to a vertex (and not per face corner). Depending on the mesh (the amount of sharing
* / number of sharp edges / size of each fan), there may be many fewer spaces than face corners,
* so they are stored in a separate array.
*/
Array<CornerNormalSpace> spaces;
/**
* The index of the data in the #spaces array for each face corner (the array size is the
* same as #Mesh::totloop). Rare -1 values define face corners without a coordinate space.
*/
Array<int> corner_space_indices;
};
void lnor_space_custom_normal_to_data(const CornerNormalSpace *lnor_space,
float3 lnor_no_custom,
const float custom_lnor[3],
short r_clnor_data[2]);
/**
* Compute split normals, i.e. vertex normals associated with each poly (hence 'loop normals').
* Useful to materialize sharp edges (or non-smooth faces) without actually modifying the geometry
* (splitting edges).
*
* \param loop_to_poly_map: Optional pre-created map from corners to their polygon.
* \param sharp_edges: Optional array of sharp edge tags, used to split the evaluated normals on
* each side of the edge.
* \param r_lnors_spacearr: Optional return data filled with information about the custom
* normals spaces for each grouped fan of face corners.
*/
void normals_calc_loop(Span<float3> vert_positions,
Span<int2> edges,
OffsetIndices<int> polys,
Span<int> corner_verts,
Span<int> corner_edges,
Span<int> loop_to_poly_map,
Span<float3> vert_normals,
Span<float3> poly_normals,
const bool *sharp_edges,
const bool *sharp_faces,
bool use_split_normals,
float split_angle,
short2 *clnors_data,
CornerNormalSpaceArray *r_lnors_spacearr,
MutableSpan<float3> r_loop_normals);
void normals_loop_custom_set(Span<float3> vert_positions,
Span<int2> edges,
OffsetIndices<int> polys,
Span<int> corner_verts,
Span<int> corner_edges,
Span<float3> vert_normals,
Span<float3> poly_normals,
const bool *sharp_faces,
MutableSpan<bool> sharp_edges,
MutableSpan<float3> r_custom_loop_normals,
MutableSpan<short2> r_clnors_data);
void normals_loop_custom_set_from_verts(Span<float3> vert_positions,
Span<int2> edges,
OffsetIndices<int> polys,
Span<int> corner_verts,
Span<int> corner_edges,
Span<float3> vert_normals,
Span<float3> poly_normals,
const bool *sharp_faces,
MutableSpan<bool> sharp_edges,
MutableSpan<float3> r_custom_vert_normals,
MutableSpan<short2> r_clnors_data);
/**
* Define sharp edges as needed to mimic 'autosmooth' from angle threshold.
*
* Used when defining an empty custom loop normals data layer,
* to keep same shading as with auto-smooth!
*
* \param sharp_faces: Optional array used to mark specific faces for sharp shading.
*/
void edges_sharp_from_angle_set(OffsetIndices<int> polys,
Span<int> corner_verts,
Span<int> corner_edges,
Span<float3> poly_normals,
const bool *sharp_faces,
const float split_angle,
MutableSpan<bool> sharp_edges);
/** \} */
/* -------------------------------------------------------------------- */
/** \name Topology Queries
* \{ */
/**
* Find the index of the next corner in the polygon, looping to the start if necessary.
* The indices are into the entire corners array, not just the polygon's corners.
*/
inline int poly_corner_prev(const IndexRange poly, const int corner)
{
return corner - 1 + (corner == poly.start()) * poly.size();
}
/**
* Find the index of the previous corner in the polygon, looping to the end if necessary.
* The indices are into the entire corners array, not just the polygon's corners.
*/
inline int poly_corner_next(const IndexRange poly, const int corner)
{
if (corner == poly.last()) {
return poly.start();
}
return corner + 1;
}
/**
* Find the index of the corner in the polygon that uses the given vertex.
* The index is into the entire corners array, not just the polygon's corners.
*/
inline int poly_find_corner_from_vert(const IndexRange poly,
const Span<int> corner_verts,
const int vert)
{
return poly[corner_verts.slice(poly).first_index(vert)];
}
/**
* Return the vertex indices on either side of the given vertex, ordered based on the winding
* direction of the polygon. The vertex must be in the polygon.
*/
inline int2 poly_find_adjecent_verts(const IndexRange poly,
const Span<int> corner_verts,
const int vert)
{
const int corner = poly_find_corner_from_vert(poly, corner_verts, vert);
return {corner_verts[poly_corner_prev(poly, corner)],
corner_verts[poly_corner_next(poly, corner)]};
}
/**
* Return the index of the edge's vertex that is not the \a vert.
* If neither edge vertex is equal to \a v, returns -1.
*/
inline int edge_other_vert(const int2 &edge, const int vert)
{
if (edge[0] == vert) {
return edge[1];
}
if (edge[1] == vert) {
return edge[0];
}
return -1;
}
/** \} */
} // namespace blender::bke::mesh
/* -------------------------------------------------------------------- */
/** \name Inline Mesh Data Access
* \{ */
inline blender::Span<blender::float3> Mesh::vert_positions() const
{
return {reinterpret_cast<const blender::float3 *>(BKE_mesh_vert_positions(this)), this->totvert};
}
inline blender::MutableSpan<blender::float3> Mesh::vert_positions_for_write()
{
return {reinterpret_cast<blender::float3 *>(BKE_mesh_vert_positions_for_write(this)),
this->totvert};
}
inline blender::Span<blender::int2> Mesh::edges() const
{
return {static_cast<const blender::int2 *>(
CustomData_get_layer_named(&this->edata, CD_PROP_INT32_2D, ".edge_verts")),
this->totedge};
}
inline blender::MutableSpan<blender::int2> Mesh::edges_for_write()
{
return {static_cast<blender::int2 *>(CustomData_get_layer_named_for_write(
&this->edata, CD_PROP_INT32_2D, ".edge_verts", this->totedge)),
this->totedge};
}
inline blender::OffsetIndices<int> Mesh::polys() const
{
return blender::Span(BKE_mesh_poly_offsets(this), this->totpoly + 1);
}
inline blender::Span<int> Mesh::poly_offsets() const
{
if (this->totpoly == 0) {
return {};
}
return {BKE_mesh_poly_offsets(this), this->totpoly + 1};
}
inline blender::MutableSpan<int> Mesh::poly_offsets_for_write()
{
if (this->totpoly == 0) {
return {};
}
return {BKE_mesh_poly_offsets_for_write(this), this->totpoly + 1};
}
inline blender::Span<int> Mesh::corner_verts() const
{
return {BKE_mesh_corner_verts(this), this->totloop};
}
inline blender::MutableSpan<int> Mesh::corner_verts_for_write()
{
return {BKE_mesh_corner_verts_for_write(this), this->totloop};
}
inline blender::Span<int> Mesh::corner_edges() const
{
return {BKE_mesh_corner_edges(this), this->totloop};
}
inline blender::MutableSpan<int> Mesh::corner_edges_for_write()
{
return {BKE_mesh_corner_edges_for_write(this), this->totloop};
}
inline blender::Span<MDeformVert> Mesh::deform_verts() const
{
const MDeformVert *dverts = BKE_mesh_deform_verts(this);
if (!dverts) {
return {};
}
return {dverts, this->totvert};
}
inline blender::MutableSpan<MDeformVert> Mesh::deform_verts_for_write()
{
return {BKE_mesh_deform_verts_for_write(this), this->totvert};
}
/** \} */