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ARB assembly language is a low-level shading language, which can be characterized as an assembly language. It was created by the OpenGL Architecture Review Board (ARB) to standardize GPU instructions controlling the hardware graphics pipeline. ==History== Texas Instruments created the first programmable graphics processor in 1985: the TMS34010, which allowed developers to load and execute code on the processor to control pixel output on a video display. This was followed by the TMS34020 and TMS34082 in 1989, providing programmable 3D graphics output. NVIDIA released its first video card NV1 in 1995, which supported quadratic texture mapping. This was followed by the Riva 128 (NV3) in 1997, providing the first hardware acceleration for Direct3D. Various video card vendors released their own accelerated boards, each with their own instruction set for GPU operations. The OpenGL Architecture Review Board (ARB) was formed in 1992, in part to establish standards for the GPU industry. The ARB and NVIDIA established a number of OpenGL extensions to standardize GPU programming:〔(【引用サイトリンク】 History of Programmability in OpenGL )〕 * EXT_texture_env_combine - provided a programmable method of combining textures. * NV_register_combiners - GeForce 256 * NV_vertex_program - GeForce 3 * NV_texture_shader - GeForce 3 * NV_texture_shader3 - GeForce 4 * NV_vertex_program2 - GeForce FX * NV_fragment_program - GeForce FX This culminated with ARB's 2002 release of * ARB_vertex_program〔(【引用サイトリンク】 ARB_vertex_program )〕 * ARB_fragment_program〔(【引用サイトリンク】 ARB_fragment_program )〕 These two extensions provided an industry standard for an assembly language that controlled the GPU pipeline for 3D vertex and interpolated pixel properties, respectively. Subsequent high-level shading languages sometimes compile to this ARB standard. While 3D developers are now more likely to use a C-like, high-level shading language for GPU programming, ARB assembly has the advantage of being supported on a wide range of hardware. Note however that some features, such as loops and conditionals, are not available in ARB assembly, and using them requires to adopt either the NV_gpu_program4 extension, or the GLSL shading language. All major graphics card manufacturers have supported ARB assembly language for years, since the NVIDIA Geforce FX series, the AMD R300-based cards (Radeon 9500 series and higher), and the Intel GMA 900.〔(【引用サイトリンク】 List of graphics cards and OpenGL renderers that support ARB assembly language )〕 However, standard ARB assembly language is only at the level of Pixel Shader 2.0 and predates GLSL, so it has very few features. While nVidia has made proprietary extensions to ARB assembly languages that combine the fast compile speed of ARB assembly with modern OpenGL 3.x features, introduced with the GeForce 8 Series, most non-nVidia OpenGL implementations do not provide the proprietary nVidia extensions to ARB assembly language〔(【引用サイトリンク】 List of graphics cards and OpenGL renderers that support nVidia's extensions to ARB assembly language )〕 and do not offer any other way to access all the shader features directly in assembly, forcing the use of GLSL even for machine generated shaders where assembly would be more appropriate. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ARB assembly language」の詳細全文を読む スポンサード リンク
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