samplerObject.h

//
// Copyright 2020 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_HD_ST_SAMPLER_OBJECT_H
#define PXR_IMAGING_HD_ST_SAMPLER_OBJECT_H

#include "pxr/pxr.h"
#include "pxr/imaging/hdSt/api.h"

#include "pxr/imaging/hgi/handle.h"
#include "pxr/imaging/hd/enums.h"
#include "pxr/imaging/hd/types.h"

#include <memory>

PXR_NAMESPACE_OPEN_SCOPE

class Hgi;
class HdStUvTextureObject;
class HdStFieldTextureObject;
class HdStPtexTextureObject;
class HdStUdimTextureObject;
class HdSt_SamplerObjectRegistry;
using HgiSamplerHandle = HgiHandle<class HgiSampler>;

using HdStSamplerObjectSharedPtr =
    std::shared_ptr<class HdStSamplerObject>;

class HdStSamplerObject
{
public:
    virtual ~HdStSamplerObject() = 0;

protected:
    explicit HdStSamplerObject(
        HdSt_SamplerObjectRegistry * samplerObjectRegistry);

    Hgi* _GetHgi() const;
    HdSt_SamplerObjectRegistry * const _samplerObjectRegistry;
};

class HdStUvSamplerObject final : public HdStSamplerObject {
public:
    HDST_API 
    HdStUvSamplerObject(
        HdStUvTextureObject const &uvTexture,
        HdSamplerParameters const &samplerParameters,
        HdSt_SamplerObjectRegistry * samplerObjectRegistry);

    HDST_API 
    ~HdStUvSamplerObject() override;

    const HgiSamplerHandle &GetSampler() const {
        return _sampler;
    }

private:
    HgiSamplerHandle _sampler;
};

class HdStFieldSamplerObject final : public HdStSamplerObject {
public:
    HdStFieldSamplerObject(
        HdStFieldTextureObject const &uvTexture,
        HdSamplerParameters const &samplerParameters,
        HdSt_SamplerObjectRegistry * samplerObjectRegistry);

    ~HdStFieldSamplerObject() override;

    const HgiSamplerHandle &GetSampler() const {
        return _sampler;
    }

private:
    HgiSamplerHandle _sampler;
};

class HdStPtexSamplerObject final : public HdStSamplerObject {
public:
    HdStPtexSamplerObject(
        HdStPtexTextureObject const &ptexTexture,
        // samplerParameters are ignored by ptex
        HdSamplerParameters const &samplerParameters,
        HdSt_SamplerObjectRegistry * samplerObjectRegistry);

    ~HdStPtexSamplerObject() override;

    const HgiSamplerHandle &GetTexelsSampler() const {
        return _texelsSampler;
    }

    const HgiSamplerHandle &GetLayoutSampler() const {
        return _layoutSampler;
    }

private:
    HgiSamplerHandle _texelsSampler;
    HgiSamplerHandle _layoutSampler;
};

class HdStUdimSamplerObject final : public HdStSamplerObject {
public:
    HdStUdimSamplerObject(
        HdStUdimTextureObject const &ptexTexture,
        // samplerParameters are ignored by udim (at least for now)
        HdSamplerParameters const &samplerParameters,
        HdSt_SamplerObjectRegistry * samplerObjectRegistry);

    ~HdStUdimSamplerObject() override;

    const HgiSamplerHandle &GetTexelsSampler() const {
        return _texelsSampler;
    }

    const HgiSamplerHandle &GetLayoutSampler() const {
        return _layoutSampler;
    }

private:
    HgiSamplerHandle _texelsSampler;
    HgiSamplerHandle _layoutSampler;
};

template<HdTextureType textureType>
struct HdSt_TypedSamplerObjectHelper;

template<HdTextureType textureType>
using HdStTypedSamplerObject =
    typename HdSt_TypedSamplerObjectHelper<textureType>::type;

template<>
struct HdSt_TypedSamplerObjectHelper<HdTextureType::Uv> {
    using type = HdStUvSamplerObject;
};

template<>
struct HdSt_TypedSamplerObjectHelper<HdTextureType::Field> {
    using type = HdStFieldSamplerObject;
};

template<>
struct HdSt_TypedSamplerObjectHelper<HdTextureType::Ptex> {
    using type = HdStPtexSamplerObject;
};

template<>
struct HdSt_TypedSamplerObjectHelper<HdTextureType::Udim> {
    using type = HdStUdimSamplerObject;
};

PXR_NAMESPACE_CLOSE_SCOPE

#endif