godot/thirdparty/embree/kernels/subdiv/catmullclark_coefficients.h

86 lines
2.6 KiB
C++

// Copyright 2009-2021 Intel Corporation
// SPDX-License-Identifier: Apache-2.0
#pragma once
#include "../common/geometry.h"
namespace embree
{
static const size_t MAX_PATCH_VALENCE = 16; //!< maximum number of vertices of a patch
static const size_t MAX_RING_FACE_VALENCE = 64; //!< maximum number of faces per ring
static const size_t MAX_RING_EDGE_VALENCE = 2*64; //!< maximum number of edges per ring
class CatmullClarkPrecomputedCoefficients
{
private:
float table_cos_2PI_div_n[MAX_RING_FACE_VALENCE+1];
float* table_limittangent_a[MAX_RING_FACE_VALENCE+1];
float* table_limittangent_b[MAX_RING_FACE_VALENCE+1];
float table_limittangent_c[MAX_RING_FACE_VALENCE+1];
__forceinline float set_cos_2PI_div_n(const size_t n) {
if (unlikely(n == 0)) return 1.0f;
return cosf(2.0f*float(pi)/(float)n);
}
__forceinline float set_limittangent_a(const size_t i, const size_t n)
{
if (unlikely(n == 0)) return 1.0f;
const float c0 = 1.0f/(float)n * 1.0f / sqrtf(4.0f + cosf(float(pi)/(float)n)*cosf(float(pi)/(float)n));
const float c1 = (1.0f/(float)n + cosf(float(pi)/(float)n) * c0);
return cosf(2.0f*float(pi)*(float)i/(float)n) * c1;
}
__forceinline float set_limittangent_b(const size_t i, const size_t n)
{
if (unlikely(n == 0)) return 1.0f;
const float c0 = 1.0f/(float)n * 1.0f / sqrtf(4.0f + cosf(float(pi)/(float)n)*cosf(float(pi)/(float)n));
return cosf((2.0f*float(pi)*i+float(pi))/(float)n) * c0;
}
__forceinline float set_limittangent_c(const size_t n)
{
if (unlikely(n == 0)) return 1.0f;
return 2.0f/16.0f * (5.0f + cosf(2.0f*float(pi)/(float)n) + cosf(float(pi)/(float)n) * sqrtf(18.0f+2.0f*cosf(2.0f*float(pi)/(float)n)));
}
public:
__forceinline float cos_2PI_div_n(const size_t n)
{
if (likely(n <= MAX_RING_FACE_VALENCE))
return table_cos_2PI_div_n[n];
else
return set_cos_2PI_div_n(n);
}
__forceinline float limittangent_a(const size_t i, const size_t n)
{
assert(n <= MAX_RING_FACE_VALENCE);
assert(i < n);
return table_limittangent_a[n][i];
}
__forceinline float limittangent_b(const size_t i, const size_t n)
{
assert(n <= MAX_RING_FACE_VALENCE);
assert(i < n);
return table_limittangent_b[n][i];
}
__forceinline float limittangent_c(const size_t n)
{
assert(n <= MAX_RING_FACE_VALENCE);
return table_limittangent_c[n];
}
static CatmullClarkPrecomputedCoefficients table;
CatmullClarkPrecomputedCoefficients();
~CatmullClarkPrecomputedCoefficients();
};
}