XCEngine/engine/src/RHI/OpenGL/OpenGLDevice.cpp

#define GLFW_INCLUDE_NONE
#include "XCEngine/RHI/OpenGL/OpenGLDevice.h"
#include "XCEngine/RHI/OpenGL/OpenGLBuffer.h"
#include "XCEngine/RHI/OpenGL/OpenGLTexture.h"
#include "XCEngine/RHI/OpenGL/OpenGLShader.h"
#include "XCEngine/RHI/OpenGL/OpenGLPipelineState.h"
#include "XCEngine/RHI/OpenGL/OpenGLFence.h"
#include "XCEngine/RHI/OpenGL/OpenGLSampler.h"
#include "XCEngine/RHI/OpenGL/OpenGLCommandList.h"
#include "XCEngine/RHI/OpenGL/OpenGLCommandQueue.h"
#include "XCEngine/RHI/OpenGL/OpenGLSwapChain.h"
#include <glad/glad.h>
#include <GLFW/glfw3.h>

namespace XCEngine {
namespace RHI {

OpenGLDevice::OpenGLDevice()
    : m_window(nullptr)
    , m_initialized(false)
    , m_ownsWindow(false) {
}

OpenGLDevice::~OpenGLDevice() {
    Shutdown();
}

bool OpenGLDevice::Initialize(const RHIDeviceDesc& desc) {
    if (m_initialized) {
        return true;
    }

    if (desc.windowHandle) {
        return InitializeWithExistingWindow(static_cast<GLFWwindow*>(desc.windowHandle));
    }

    std::string titleStr = "XCEngine";
    if (!desc.appName.empty()) {
        titleStr = std::string(desc.appName.begin(), desc.appName.end());
    }
    
    return CreateRenderWindow(desc.width, desc.height, titleStr.c_str(), desc.enableDebugLayer);
}

bool OpenGLDevice::CreateRenderWindow(int width, int height, const char* title, bool enableDebug) {
    if (m_initialized) {
        return true;
    }

    static bool glfwInitialized = false;
    if (!glfwInitialized) {
        glfwInit();
        glfwInitialized = true;
    }

    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);

    m_window = glfwCreateWindow(width, height, title, nullptr, nullptr);
    if (!m_window) {
        return false;
    }

    glfwSetWindowShouldClose(m_window, GLFW_FALSE);

    m_ownsWindow = true;
    return InitializeWithExistingWindow(m_window);
}

bool OpenGLDevice::InitializeWithExistingWindow(GLFWwindow* window) {
    if (m_initialized) {
        return true;
    }

    m_window = window;
    if (!m_window) {
        return false;
    }

    glfwMakeContextCurrent(m_window);

    if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress)) {
        return false;
    }

    const char* vendor = reinterpret_cast<const char*>(glGetString(GL_VENDOR));
    const char* renderer = reinterpret_cast<const char*>(glGetString(GL_RENDERER));
    const char* version = reinterpret_cast<const char*>(glGetString(GL_VERSION));
    
    m_deviceInfo.vendor = std::wstring(vendor ? vendor : "", vendor ? vendor + strlen(vendor) : nullptr);
    m_deviceInfo.renderer = std::wstring(renderer ? renderer : "", renderer ? renderer + strlen(renderer) : nullptr);
    m_deviceInfo.version = std::wstring(version ? version : "", version ? version + strlen(version) : nullptr);
    
    GLint majorVersion = 0, minorVersion = 0;
    glGetIntegerv(GL_MAJOR_VERSION, &majorVersion);
    glGetIntegerv(GL_MINOR_VERSION, &minorVersion);
    m_deviceInfo.majorVersion = static_cast<uint32_t>(majorVersion);
    m_deviceInfo.minorVersion = static_cast<uint32_t>(minorVersion);
    
    m_capabilities.majorVersion = majorVersion;
    m_capabilities.minorVersion = minorVersion;
    m_capabilities.bSupportsGeometryShaders = true;
    m_capabilities.bSupportsComputeShaders = GLVersion.major >= 4 && GLVersion.minor >= 3;
    m_capabilities.bSupportsTessellation = GLVersion.major >= 4 && GLVersion.minor >= 1;
    m_capabilities.bSupportsExplicitMultiThreading = false;
    
    GLint maxTexSize = 0;
    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &maxTexSize);
    m_capabilities.maxTexture2DSize = static_cast<uint32_t>(maxTexSize);
    
    GLint maxCubeSize = 0;
    glGetIntegerv(GL_MAX_CUBE_MAP_TEXTURE_SIZE, &maxCubeSize);
    m_capabilities.maxTextureCubeSize = static_cast<uint32_t>(maxCubeSize);
    
    GLint maxRenderTargets = 0;
    glGetIntegerv(GL_MAX_DRAW_BUFFERS, &maxRenderTargets);
    m_capabilities.maxRenderTargets = static_cast<uint32_t>(maxRenderTargets);
    m_capabilities.maxColorAttachments = static_cast<uint32_t>(maxRenderTargets);
    
    GLint maxViewports = 0;
    glGetIntegerv(GL_MAX_VIEWPORTS, &maxViewports);
    m_capabilities.maxViewports = static_cast<uint32_t>(maxViewports);
    
    GLint maxAnisotropy = 0;
    glGetIntegerv(GL_MAX_TEXTURE_MAX_ANISOTROPY, &maxAnisotropy);
    m_capabilities.maxAnisotropy = static_cast<uint32_t>(maxAnisotropy);
    
    GLint maxAttribs = 0;
    glGetIntegerv(GL_MAX_VERTEX_ATTRIBS, &maxAttribs);
    m_capabilities.maxVertexAttribs = static_cast<uint32_t>(maxAttribs);
    
    m_initialized = true;
    return true;
}

void OpenGLDevice::Shutdown() {
    if (m_ownsWindow && m_window) {
        glfwDestroyWindow(m_window);
    }
    m_window = nullptr;
    m_initialized = false;
    m_ownsWindow = false;
}

void OpenGLDevice::SwapBuffers() {
    if (m_window) {
        glfwSwapBuffers(m_window);
    }
}

bool OpenGLDevice::PollEvents() {
    glfwPollEvents();
    return !glfwWindowShouldClose(m_window);
}

void OpenGLDevice::SetShouldClose(bool shouldClose) {
    if (m_window) {
        glfwSetWindowShouldClose(m_window, shouldClose ? GLFW_TRUE : GLFW_FALSE);
    }
}

bool OpenGLDevice::ShouldClose() const {
    return m_window && glfwWindowShouldClose(m_window) == GLFW_TRUE;
}

RHIBuffer* OpenGLDevice::CreateBuffer(const BufferDesc& desc) {
    auto* buffer = new OpenGLBuffer();
    OpenGLBufferType bufferType = OpenGLBufferType::Vertex;
    
    switch (desc.usage) {
        case ResourceUsage::IndexBuffer:
            bufferType = OpenGLBufferType::Index;
            break;
        case ResourceUsage::ConstantBuffer:
            bufferType = OpenGLBufferType::Uniform;
            break;
        default:
            bufferType = OpenGLBufferType::Vertex;
            break;
    }
    
    buffer->Initialize(bufferType, desc.size, nullptr, desc.cpuAccess == CPUAccess::Write);
    return buffer;
}

RHITexture* OpenGLDevice::CreateTexture(const TextureDesc& desc) {
    auto* texture = new OpenGLTexture();
    
    OpenGLTextureType type = OpenGLTextureType::Texture2D;
    switch (desc.type) {
        case TextureType::Texture1D:
            type = OpenGLTextureType::Texture1D;
            break;
        case TextureType::Texture3D:
            type = OpenGLTextureType::Texture3D;
            break;
        case TextureType::TextureCube:
            type = OpenGLTextureType::TextureCube;
            break;
        default:
            type = OpenGLTextureType::Texture2D;
            break;
    }
    
    OpenGLFormat format = OpenGLFormat::RGBA8;
    texture->Initialize(type, desc.width, desc.height, desc.depth, desc.mipLevels, format, nullptr);
    return texture;
}

RHISwapChain* OpenGLDevice::CreateSwapChain(const SwapChainDesc& desc) {
    auto* swapChain = new OpenGLSwapChain();
    if (m_window) {
        swapChain->Initialize(m_window, desc.width, desc.height);
    }
    return swapChain;
}

RHICommandList* OpenGLDevice::CreateCommandList(const CommandListDesc& desc) {
    auto* cmdList = new OpenGLCommandList();
    return cmdList;
}

RHICommandQueue* OpenGLDevice::CreateCommandQueue(const CommandQueueDesc& desc) {
    auto* queue = new OpenGLCommandQueue();
    return queue;
}

RHIShader* OpenGLDevice::CompileShader(const ShaderCompileDesc& desc) {
    auto* shader = new OpenGLShader();
    if (desc.sourceData && desc.sourceSize > 0) {
        shader->Compile(static_cast<const char*>(desc.sourceData), desc.sourceSize);
    } else if (desc.filePath) {
        shader->CompileFromFile(desc.filePath);
    }
    return shader;
}

RHIPipelineState* OpenGLDevice::CreatePipelineState(const PipelineStateDesc& desc) {
    auto* pso = new OpenGLPipelineState();
    return pso;
}

RHIFence* OpenGLDevice::CreateFence(const FenceDesc& desc) {
    auto* fence = new OpenGLFence();
    fence->Initialize(desc.initialValue > 0);
    return fence;
}

RHISampler* OpenGLDevice::CreateSampler(const SamplerDesc& desc) {
    auto* sampler = new OpenGLSampler();
    OpenGLSamplerDesc samplerDesc = {};
    sampler->Initialize(samplerDesc);
    return sampler;
}

const RHICapabilities& OpenGLDevice::GetCapabilities() const {
    return m_capabilities;
}

const RHIDeviceInfo& OpenGLDevice::GetDeviceInfo() const {
    return m_deviceInfo;
}

void* OpenGLDevice::GetNativeDevice() {
    return nullptr;
}

void* OpenGLDevice::GetNativeHandle() const {
    return nullptr;
}

} // namespace RHI
} // namespace XCEngine