sphereMeshGenerator.h

//
// Copyright 2022 Pixar
//
// Licensed under the Apache License, Version 2.0 (the "Apache License")
// with the following modification; you may not use this file except in
// compliance with the Apache License and the following modification to it:
// Section 6. Trademarks. is deleted and replaced with:
//
// 6. Trademarks. This License does not grant permission to use the trade
//    names, trademarks, service marks, or product names of the Licensor
//    and its affiliates, except as required to comply with Section 4(c) of
//    the License and to reproduce the content of the NOTICE file.
//
// You may obtain a copy of the Apache License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the Apache License with the above modification is
// distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the Apache License for the specific
// language governing permissions and limitations under the Apache License.
//
#ifndef PXR_IMAGING_GEOM_UTIL_SPHERE_MESH_GENERATOR_H
#define PXR_IMAGING_GEOM_UTIL_SPHERE_MESH_GENERATOR_H

#include "pxr/imaging/geomUtil/api.h"
#include "pxr/imaging/geomUtil/meshGeneratorBase.h"

#include "pxr/pxr.h"

PXR_NAMESPACE_OPEN_SCOPE

class GfMatrix4d;
class PxOsdMeshTopology;

class GeomUtilSphereMeshGenerator final
    : public GeomUtilMeshGeneratorBase
{
public:
    static constexpr size_t minNumRadial = 3;
    static constexpr size_t minNumAxial = 2;

    GEOMUTIL_API
    static size_t ComputeNumPoints(
        const size_t numRadial,
        const size_t numAxial,
        const bool closedSweep = true);

    GEOMUTIL_API
    static PxOsdMeshTopology GenerateTopology(
        const size_t numRadial,
        const size_t numAxial,
        const bool closedSweep = true);

    template<typename PointIterType,
             typename ScalarType,
             typename Enabled =
                typename _EnableIfGfVec3Iterator<PointIterType>::type>
    static void GeneratePoints(
        PointIterType iter,
        const size_t numRadial,
        const size_t numAxial,
        const ScalarType radius,
        const GfMatrix4d* framePtr = nullptr)
    {
        constexpr ScalarType sweep = 360;
        GeneratePoints(iter, numRadial, numAxial, radius, sweep, framePtr);
    }

    template<typename PointIterType,
             typename ScalarType,
             typename Enabled =
                typename _EnableIfGfVec3Iterator<PointIterType>::type>
    static void GeneratePoints(
        PointIterType iter,
        const size_t numRadial,
        const size_t numAxial,
        const ScalarType radius,
        const ScalarType sweepDegrees,
        const GfMatrix4d* framePtr = nullptr)
    {
        using PointType =
            typename std::iterator_traits<PointIterType>::value_type;

        _GeneratePointsImpl(numRadial, numAxial, radius, sweepDegrees,
            framePtr ? _PointWriter<PointType>(iter, framePtr)
                     : _PointWriter<PointType>(iter));
    }

    using GeomUtilMeshGeneratorBase::GeneratePoints;

private:
    
    template<typename PointType>
    static void _GeneratePointsImpl(
        const size_t numRadial,
        const size_t numAxial,
        const typename PointType::ScalarType radius,
        const typename PointType::ScalarType sweepDegrees,
        const _PointWriter<PointType>& ptWriter);
};

PXR_NAMESPACE_CLOSE_SCOPE

#endif // PXR_IMAGING_GEOM_UTIL_SPHERE_MESH_GENERATOR_H