shaderFunctionDesc.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_HGI_SHADERFUNCTIONDESC_H
#define PXR_IMAGING_HGI_SHADERFUNCTIONDESC_H

#include "pxr/pxr.h"
#include "pxr/imaging/hgi/api.h"
#include "pxr/imaging/hgi/enums.h"
#include "pxr/imaging/hgi/types.h"

#include <string>
#include <vector>

PXR_NAMESPACE_OPEN_SCOPE


struct HgiShaderFunctionTextureDesc
{
    HGI_API
    HgiShaderFunctionTextureDesc();

    std::string nameInShader;
    uint32_t dimensions;
    HgiFormat format;
    HgiShaderTextureType textureType;
    uint32_t bindIndex;
    size_t arraySize;
    bool writable;
};

using HgiShaderFunctionTextureDescVector =
    std::vector<HgiShaderFunctionTextureDesc>;

HGI_API
bool operator==(
    const HgiShaderFunctionTextureDesc& lhs,
    const HgiShaderFunctionTextureDesc& rhs);

HGI_API
bool operator!=(
    const HgiShaderFunctionTextureDesc& lhs,
    const HgiShaderFunctionTextureDesc& rhs);

struct HgiShaderFunctionBufferDesc
{
    HGI_API
    HgiShaderFunctionBufferDesc();

    std::string nameInShader;
    std::string type;
    uint32_t bindIndex;
    uint32_t arraySize;
    HgiBindingType binding;
    bool writable;
};

using HgiShaderFunctionBufferDescVector =
    std::vector<HgiShaderFunctionBufferDesc>;

HGI_API
bool operator==(
    const HgiShaderFunctionBufferDesc& lhs,
    const HgiShaderFunctionBufferDesc& rhs);

HGI_API
bool operator!=(
    const HgiShaderFunctionBufferDesc& lhs,
    const HgiShaderFunctionBufferDesc& rhs);

struct HgiShaderFunctionParamDesc
{
    HGI_API
    HgiShaderFunctionParamDesc();

    std::string nameInShader;
    std::string type;
    int32_t location;
    int32_t interstageSlot;
    HgiInterpolationType interpolation;
    HgiSamplingType sampling;
    HgiStorageType storage;
    std::string role;
    std::string arraySize;
};

using HgiShaderFunctionParamDescVector =
    std::vector<HgiShaderFunctionParamDesc>;

HGI_API
bool operator==(
    const HgiShaderFunctionParamDesc& lhs,
    const HgiShaderFunctionParamDesc& rhs);

HGI_API
bool operator!=(
    const HgiShaderFunctionParamDesc& lhs,
    const HgiShaderFunctionParamDesc& rhs);

struct HgiShaderFunctionParamBlockDesc
{
    HGI_API
    HgiShaderFunctionParamBlockDesc();

    struct Member {
        std::string name;
        std::string type;
    };
    using MemberVector = std::vector<Member>;

    std::string blockName;
    std::string instanceName;
    MemberVector members;
    std::string arraySize;
    int32_t interstageSlot;
};

using HgiShaderFunctionParamBlockDescVector =
    std::vector<HgiShaderFunctionParamBlockDesc>;

HGI_API
bool operator==(
    const HgiShaderFunctionParamBlockDesc& lhs,
    const HgiShaderFunctionParamBlockDesc& rhs);

HGI_API
bool operator!=(
    const HgiShaderFunctionParamBlockDesc& lhs,
    const HgiShaderFunctionParamBlockDesc& rhs);

HGI_API
bool operator==(
    const HgiShaderFunctionParamBlockDesc::Member& lhs,
    const HgiShaderFunctionParamBlockDesc::Member& rhs);

HGI_API
bool operator!=(
    const HgiShaderFunctionParamBlockDesc::Member& lhs,
    const HgiShaderFunctionParamBlockDesc::Member& rhs);

struct HgiShaderFunctionComputeDesc
{
    HGI_API
    HgiShaderFunctionComputeDesc();

    GfVec3i localSize;
};

HGI_API
bool operator==(
        const HgiShaderFunctionComputeDesc& lhs,
        const HgiShaderFunctionComputeDesc& rhs);

HGI_API
bool operator!=(
        const HgiShaderFunctionComputeDesc& lhs,
        const HgiShaderFunctionComputeDesc& rhs);

struct HgiShaderFunctionTessellationDesc
{
    enum class PatchType { Triangles, Quads, Isolines };
    enum class Spacing { Equal, FractionalEven, FractionalOdd };
    enum class Ordering { CW, CCW };
    HGI_API
    HgiShaderFunctionTessellationDesc();

    PatchType patchType;
    Spacing spacing;
    Ordering ordering;
    std::string numVertsPerPatchIn;
    std::string numVertsPerPatchOut;
};

HGI_API
bool operator==(
        const HgiShaderFunctionTessellationDesc& lhs,
        const HgiShaderFunctionTessellationDesc& rhs);

HGI_API
bool operator!=(
        const HgiShaderFunctionTessellationDesc& lhs,
        const HgiShaderFunctionTessellationDesc& rhs);

struct HgiShaderFunctionGeometryDesc
{
    enum class InPrimitiveType { 
        Points, Lines, LinesAdjacency, Triangles, TrianglesAdjacency };
    enum class OutPrimitiveType { 
        Points, LineStrip, TriangleStrip };

    HGI_API
    HgiShaderFunctionGeometryDesc();

    InPrimitiveType inPrimitiveType;
    OutPrimitiveType outPrimitiveType;
    std::string outMaxVertices;
};

HGI_API
bool operator==(
        const HgiShaderFunctionGeometryDesc& lhs,
        const HgiShaderFunctionGeometryDesc& rhs);

HGI_API
bool operator!=(
        const HgiShaderFunctionGeometryDesc& lhs,
        const HgiShaderFunctionGeometryDesc& rhs);

struct HgiShaderFunctionFragmentDesc
{
    HGI_API
    HgiShaderFunctionFragmentDesc();

    bool earlyFragmentTests;

};

HGI_API
bool operator==(
        const HgiShaderFunctionFragmentDesc& lhs,
        const HgiShaderFunctionFragmentDesc& rhs);

HGI_API
bool operator!=(
        const HgiShaderFunctionFragmentDesc& lhs,
        const HgiShaderFunctionFragmentDesc& rhs);

struct HgiShaderFunctionDesc
{
    HGI_API
    HgiShaderFunctionDesc();
    std::string debugName;
    HgiShaderStage shaderStage;
    const char *shaderCodeDeclarations;
    const char *shaderCode;
    std::string *generatedShaderCodeOut;
    std::vector<HgiShaderFunctionTextureDesc> textures;
    std::vector<HgiShaderFunctionBufferDesc> buffers;
    std::vector<HgiShaderFunctionParamDesc> constantParams;
    std::vector<HgiShaderFunctionParamDesc> stageGlobalMembers;
    std::vector<HgiShaderFunctionParamDesc> stageInputs;
    std::vector<HgiShaderFunctionParamDesc> stageOutputs;
    std::vector<HgiShaderFunctionParamBlockDesc> stageInputBlocks;
    std::vector<HgiShaderFunctionParamBlockDesc> stageOutputBlocks;
    HgiShaderFunctionComputeDesc computeDescriptor;
    HgiShaderFunctionTessellationDesc tessellationDescriptor;
    HgiShaderFunctionGeometryDesc geometryDescriptor;
    HgiShaderFunctionFragmentDesc fragmentDescriptor;
};

using HgiShaderFunctionDescVector =
    std::vector<HgiShaderFunctionDesc>;

HGI_API
bool operator==(
    const HgiShaderFunctionDesc& lhs,
    const HgiShaderFunctionDesc& rhs);

HGI_API
bool operator!=(
    const HgiShaderFunctionDesc& lhs,
    const HgiShaderFunctionDesc& rhs);

HGI_API
void
HgiShaderFunctionAddTexture(
    HgiShaderFunctionDesc *desc,
    const std::string &nameInShader,
    const uint32_t bindIndex = 0,
    uint32_t dimensions = 2,
    const HgiFormat &format = HgiFormatFloat32Vec4,
    const HgiShaderTextureType textureType = HgiShaderTextureTypeTexture);

HGI_API
void
HgiShaderFunctionAddArrayOfTextures(
    HgiShaderFunctionDesc *desc,
    const std::string &nameInShader,
    const uint32_t arraySize,
    const uint32_t bindIndex = 0,
    const uint32_t dimensions = 2,
    const HgiFormat &format = HgiFormatFloat32Vec4,
    const HgiShaderTextureType textureType = HgiShaderTextureTypeTexture);

HGI_API
void
HgiShaderFunctionAddWritableTexture(
    HgiShaderFunctionDesc *desc,
    const std::string &nameInShader,
    const uint32_t bindIndex = 0,
    const uint32_t dimensions = 2,
    const HgiFormat &format = HgiFormatFloat32Vec4,
    const HgiShaderTextureType textureType = HgiShaderTextureTypeTexture);

HGI_API
void
HgiShaderFunctionAddBuffer(
    HgiShaderFunctionDesc *desc,
    const std::string &nameInShader,
    const std::string &type,
    const uint32_t bindIndex,
    HgiBindingType binding,
    const uint32_t arraySize = 0);

HGI_API
void
HgiShaderFunctionAddWritableBuffer(
    HgiShaderFunctionDesc *desc,
    const std::string &nameInShader,
    const std::string &type,
    const uint32_t bindIndex);

HGI_API
void
HgiShaderFunctionAddConstantParam(
    HgiShaderFunctionDesc *desc,
    const std::string &nameInShader,
    const std::string &type,
    const std::string &role = std::string());

HGI_API
void
HgiShaderFunctionAddStageInput(
    HgiShaderFunctionDesc *desc,
    const std::string &nameInShader,
    const std::string &type,
    const std::string &role = std::string());

HGI_API
void
HgiShaderFunctionAddStageInput(
        HgiShaderFunctionDesc *functionDesc,
        HgiShaderFunctionParamDesc const &paramDesc);

HGI_API
void
HgiShaderFunctionAddGlobalVariable(
   HgiShaderFunctionDesc *desc,
   const std::string &nameInShader,
   const std::string &type,
   const std::string &arraySize);

HGI_API
void
HgiShaderFunctionAddStageOutput(
    HgiShaderFunctionDesc *desc,
    const std::string &nameInShader,
    const std::string &type,
    const std::string &role = std::string());

HGI_API
void
HgiShaderFunctionAddStageOutput(
    HgiShaderFunctionDesc *desc,
    const std::string &nameInShader,
    const std::string &type,
    const uint32_t location);

HGI_API
void
HgiShaderFunctionAddStageOutput(
        HgiShaderFunctionDesc *functionDesc,
        HgiShaderFunctionParamDesc const &paramDesc);

PXR_NAMESPACE_CLOSE_SCOPE

#endif