ARBgpushaderfp64

ARBgpushaderfp64 refers to a specific shader model variant used in graphics programming, particularly within the Direct3D and Vulkan APIs. The term combines several components: "ARB" (a historical reference to the ARB Working Group, which standardized many OpenGL extensions), "gpushader" (indicating a geometry shader stage), and "fp64" (denoting support for 64-bit floating-point precision). While not an official OpenGL extension, the naming convention suggests compatibility with extensions that leverage advanced shader capabilities.

The "fp64" suffix implies support for double-precision floating-point operations (64-bit floats) within the geometry shader stage. This is distinct from the more common 32-bit floating-point precision (fp32) and is often used in scientific computing, high-precision simulations, or applications requiring greater numerical accuracy. Geometry shaders process vertex data before it reaches the rasterization stage, allowing for dynamic vertex generation, tessellation, or stream output.

This shader model variant is relevant in modern graphics programming, particularly when targeting APIs that support double-precision arithmetic, such as Vulkan with the `VK_KHR_shader_float_controls` extension or Direct3D 12 with its precision control features. Developers may enable fp64 support in geometry shaders to ensure compatibility with high-precision workloads while maintaining performance where possible.

While ARBgpushaderfp64 is not an officially documented extension, similar functionality exists in modern graphics APIs, allowing developers to explicitly request or disable double-precision operations based on hardware capabilities and application requirements. The term serves as a conceptual reference to shader models that extend beyond standard floating-point precision.