samplerObject.h

//
// Copyright 2020 Pixar
//
// Licensed under the terms set forth in the LICENSE.txt file available at
// https://openusd.org/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/hdSt/enums.h"
 
#include "pxr/imaging/hgi/handle.h"
#include "pxr/imaging/hd/types.h"
 
#include <memory>
 
PXR_NAMESPACE_OPEN_SCOPE
 
class Hgi;
class HdStCubemapTextureObject;
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<HdStTextureType textureType>
struct HdSt_TypedSamplerObjectHelper;
 
template<HdStTextureType textureType>
using HdStTypedSamplerObject =
    typename HdSt_TypedSamplerObjectHelper<textureType>::type;
 
template<>
struct HdSt_TypedSamplerObjectHelper<HdStTextureType::Uv> {
    using type = HdStUvSamplerObject;
};
 
template<>
struct HdSt_TypedSamplerObjectHelper<HdStTextureType::Field> {
    using type = HdStFieldSamplerObject;
};
 
template<>
struct HdSt_TypedSamplerObjectHelper<HdStTextureType::Ptex> {
    using type = HdStPtexSamplerObject;
};
 
template<>
struct HdSt_TypedSamplerObjectHelper<HdStTextureType::Udim> {
    using type = HdStUdimSamplerObject;
};
 
template<>
struct HdSt_TypedSamplerObjectHelper<HdStTextureType::Cubemap> {
    using type = HdStUvSamplerObject;
};
 
PXR_NAMESPACE_CLOSE_SCOPE
 
#endif