zoujiaqing / LLGL

Low Level Graphics Library (LLGL) is a thin abstraction layer for the modern graphics APIs OpenGL, Direct3D, Vulkan, and Metal

Low Level Graphics Library (LLGL)

Documentation

• NOTE: This repository receives bug fixes only, but no major updates. Pull requests may still be accepted.
• Version: 0.03 Beta (see ChangeLog)
• Getting Started with LLGL (PDF) with Introduction, Hello Triangle Tutorial, and Extensibility Example with GLFW
• LLGL Reference Manual (PDF)
• LLGL Coding Conventions (PDF)
• Examples and Tutorials for C++
• Examples for C#

Platform Support

Platform	CI	D3D12	D3D11	Vulkan	OpenGL	OpenGLES 3	Metal
Windows		✔️	✔️	✔️	✔️	N/A	N/A
GNU/Linux		N/A	N/A	✔️	✔️	N/A	N/A
macOS		N/A	N/A	N/A	✔️	N/A	✔️
iOS		N/A	N/A	N/A	N/A	✖️	✔️
Android		N/A	N/A	✖️	N/A	✔️	N/A

Build Notes

Build scripts are provided for CMake.

Windows

Visual Studio 2015 or later is required to build LLGL on Windows.

macOS, iOS

Xcode 9 or later is required to build LLGL on macOS and iOS.

GNU/Linux

The following development libraries are required to build LLGL on GNU/Linux:

• X11: libx11-dev
• Xrandr: libxrandr-dev

Android

The Android NDK with at least API level 21 is required. The build script to generate project files is currently only supported on GNU/Linux and requires CMake 3.10 or later and the Code::Blocks IDE.

This platform support is currently in an experimental state.

Installing LuaBridge (vcpkg)

Alternatively, you can build and install LLGL using vcpkg dependency manager:

    git clone https://github.com/Microsoft/vcpkg.git
    cd vcpkg
    ./bootstrap-vcpkg.sh
    ./vcpkg integrate install
    ./vcpkg install llgl

The llgl port in vcpkg is kept up to date by Microsoft team members and community contributors. If the version is out of date, please create an issue or pull request on the vcpkg repository.

Thin Abstraction Layer

// Unified Interface:
CommandBuffer::DrawIndexed(std::uint32_t numIndices, std::uint32_t firstIndex);

// OpenGL Implementation:
void GLCommandBuffer::DrawIndexed(std::uint32_t numIndices, std::uint32_t firstIndex) {
    const GLintptr indices = (renderState_.indexBufferOffset + firstIndex * renderState_.indexBufferStride);
    glDrawElements(
        renderState_.drawMode,
        static_cast<GLsizei>(numIndices),
        renderState_.indexBufferDataType,
        reinterpret_cast<const GLvoid*>(indices)
    );
}

// Direct3D 11 Implementation
void D3D11CommandBuffer::DrawIndexed(std::uint32_t numIndices, std::uint32_t firstIndex) {
    context_->DrawIndexed(numIndices, firstIndex, 0);
}

// Direct3D 12 Implementation
void D3D12CommandBuffer::DrawIndexed(std::uint32_t numIndices, std::uint32_t firstIndex) {
    commandList_->DrawIndexedInstanced(numIndices, 1, firstIndex, 0, 0);
}

// Vulkan Implementation
void VKCommandBuffer::DrawIndexed(std::uint32_t numIndices, std::uint32_t firstIndex) {
    vkCmdDrawIndexed(commandBuffer_, numIndices, 1, firstIndex, 0, 0);
}

// Metal implementation
void MTCommandBuffer::DrawIndexed(std::uint32_t numIndices, std::uint32_t firstIndex) {
    if (numPatchControlPoints_ > 0) {
        [renderEncoder_
            drawIndexedPatches:             numPatchControlPoints_
            patchStart:                     static_cast<NSUInteger>(firstIndex) / numPatchControlPoints_
            patchCount:                     static_cast<NSUInteger>(numIndices) / numPatchControlPoints_
            patchIndexBuffer:               nil
            patchIndexBufferOffset:         0
            controlPointIndexBuffer:        indexBuffer_
            controlPointIndexBufferOffset:  indexTypeSize_ * (static_cast<NSUInteger>(firstIndex))
            instanceCount:                  1
            baseInstance:                   0
        ];
    } else {
        [renderEncoder_
            drawIndexedPrimitives:  primitiveType_
            indexCount:             static_cast<NSUInteger>(numIndices)
            indexType:              indexType_
            indexBuffer:            indexBuffer_
            indexBufferOffset:      indexTypeSize_ * static_cast<NSUInteger>(firstIndex)
        ];
    }
}