GDC: Khronos Group Releases OpenGL 4.0 Specification

Khronos Group, the industry consortium behind the OpenGL 2D and 3D graphics standards, released its OpenGL 4.0 specification, an update promising to bring the "latest in cross-platform graphics acceleration and functionality" to PCs and workstations. Khronos's OpenGL ARB (Architecture Review Board) working group defined the OpenGL 4.0 specification, which now includes the GLSL 4.00 update to the OpenGL Shading language. The group says this will enable developers to access the latest generation of GPU acceleration with enhanced graphics quality, acceleration performance, and programming flexibility. The new release is also designed to continue the evolution of the royalty-free OpenGL standard to enable graphics developers to "portably access cutting-edge GPU functionality across diverse operating systems and platforms". The full specification is available for download at the official OpenGL website. OpenGL 4.0 is meant to improve "the close interoperability with OpenCL for accelerating computationally intensive visual applications". The new specification continues support for both the Core and Compatibility profiles introduced with OpenGL 3.2, which enables developers to "use a streamlined API or retain backwards compatibility for existing OpenGL code". Khronos listed the following benefits OpenGL 4.0 offers to application developers: - two new shader stages that enable the GPU to offload geometry tessellation from the CPU; - per-sample fragment shaders and programmable fragment shader input positions for increased rendering quality and anti-aliasing flexibility; - drawing of data generated by OpenGL, or external APIs such as OpenCL, without CPU intervention; - shader subroutines for significantly increased programming flexibility; - separation of texture state and texture data through the addition of a new object type called sampler objects; - 64-bit double precision floating point shader operations and inputs/outputs for increased rendering accuracy and quality; - performance improvements, including instanced geometry shaders, instanced arrays, and a new timer query. The group also released an OpenGL 3.3 specification with ARB extensions to enable as much OpenGL 4.0 functionality as possible on previous generation GPU hardware. Khronos believes this will provide maximum flexibility and platform coverage for application developers. The full OpenGL 3.3 specification is also available for download at the official OpenGL website. "OpenGL 4.0 continues the ARB’s schedule-driven roll-out of new functionality, and this significant major release enables developers to access leading-edge GPU functionality across multiple platforms with full backwards compatibility," says Khronos Group president and Nvidia vice president Neil Trevett." He adds, "OpenGL continues to be a keystone in the Khronos API ecosystem, through driving innovation into OpenGL ES and WebGL to bring high-performance programmable graphics to mobile platforms and the Web, and by interoperating with OpenCL to create a seamless visual and compute platform for application developers."