OpenGL
This is the original version of the OpenGL standard interface for 3D graphics on desktop systems. Microsoft also offers a similar standard, Direct3D® (D3D) interface. Both are commonly used on Windows® platforms, but Direct3D® is available only on Windows, where it’s dominate. OpenGL is the dominant standard on all other operating system platforms. OpenGL is known for its architectural stability. There have been several minor revisions, as the standard has evolved, but only one major revision, 2.0. Prior to the 2.0 version, OpenGL supported only vertex shading. Version 2.0 added pixel-shading capabilities. OpenGL has always required floating-point support, which is usually available on desktop systems.
OpenGL is essentially a library of functions which are designed so that they can be ported to any graphics-acceleration hardware without changing the application code that uses these functions. This library of functions is contained within a device driver known as the Installable Client Driver. Hence, OpenGL implementations are often referred to as “drivers” or “libraries”.
One of the great strengths of OpenGL is the abundance of quality resources for learning how to use it, including books, tutorials, online coding examples and classes. In particular, there are two essential books that every developer should have as a starting point – often referred to as the Red and Blue books. These are the official OpenGL Reference Manual and Programming Guide:
• The OpenGL Reference Manual
• The OpenGL Programming Guide
The complete specifications for OpenGL are also available publicly at:
www.opengl.org/
These are great resources for learning OpenGL and for reference during development, but keep in mind that they cover the desktop version which is quite large compared to the embedded OpenGL ES versions supported on the OMAP 2 and 3 platforms.
OpenGL ES 1.1
This is the fixed-function version of the OpenGL ES standard for doing vertex shading on embedded devices. This is the most widely used 3D graphics interface for embedded and mobile devices today. It is a subset of the OpenGL standard used widely on desktop systems. OpenGL ES also supports 2D graphics features for antialiased text, geometry and raster image processing. This embedded version is royalty-free and the complete specifications are publicly available at:
www.khronos.org/opengles/
There are two profiles of OpenGL® ES 1.1, Common and Common Lite. The Common Lite profile is for devices with no floating-point capability. Since all OMAP 2 and 3 devices have floating-point capabilities in hardware, only the Common profile is supported. Supported OSes include embedded Linux, Windows® Embedded® CE and Symbian OS™.
OpenGL ES is the most widely used 3D graphics interface on these platforms. Porting to other operating system platforms is available through TI approved graphics partners. Although this version of OpenGL ES is designed primarily for vertex shading, there is also support for a type of DOT3 per-pixel lighting known as bump mapping. Refer to the ChameleonMan example program in the software development kit (SDK) for an example of this. OpenGL ES 1.1 was preceded by version 1.0. The new functionality includes better support for multitexturing, automatic mipmap generation, vertex buffer objects, state queries, user clip planes and greater control over point rendering.
This is the original version of the OpenGL standard interface for 3D graphics on desktop systems. Microsoft also offers a similar standard, Direct3D® (D3D) interface. Both are commonly used on Windows® platforms, but Direct3D® is available only on Windows, where it’s dominate. OpenGL is the dominant standard on all other operating system platforms. OpenGL is known for its architectural stability. There have been several minor revisions, as the standard has evolved, but only one major revision, 2.0. Prior to the 2.0 version, OpenGL supported only vertex shading. Version 2.0 added pixel-shading capabilities. OpenGL has always required floating-point support, which is usually available on desktop systems.
OpenGL is essentially a library of functions which are designed so that they can be ported to any graphics-acceleration hardware without changing the application code that uses these functions. This library of functions is contained within a device driver known as the Installable Client Driver. Hence, OpenGL implementations are often referred to as “drivers” or “libraries”.
One of the great strengths of OpenGL is the abundance of quality resources for learning how to use it, including books, tutorials, online coding examples and classes. In particular, there are two essential books that every developer should have as a starting point – often referred to as the Red and Blue books. These are the official OpenGL Reference Manual and Programming Guide:
• The OpenGL Reference Manual
• The OpenGL Programming Guide
The complete specifications for OpenGL are also available publicly at:
www.opengl.org/
These are great resources for learning OpenGL and for reference during development, but keep in mind that they cover the desktop version which is quite large compared to the embedded OpenGL ES versions supported on the OMAP 2 and 3 platforms.
OpenGL ES 1.1
This is the fixed-function version of the OpenGL ES standard for doing vertex shading on embedded devices. This is the most widely used 3D graphics interface for embedded and mobile devices today. It is a subset of the OpenGL standard used widely on desktop systems. OpenGL ES also supports 2D graphics features for antialiased text, geometry and raster image processing. This embedded version is royalty-free and the complete specifications are publicly available at:
www.khronos.org/opengles/
There are two profiles of OpenGL® ES 1.1, Common and Common Lite. The Common Lite profile is for devices with no floating-point capability. Since all OMAP 2 and 3 devices have floating-point capabilities in hardware, only the Common profile is supported. Supported OSes include embedded Linux, Windows® Embedded® CE and Symbian OS™.
OpenGL ES is the most widely used 3D graphics interface on these platforms. Porting to other operating system platforms is available through TI approved graphics partners. Although this version of OpenGL ES is designed primarily for vertex shading, there is also support for a type of DOT3 per-pixel lighting known as bump mapping. Refer to the ChameleonMan example program in the software development kit (SDK) for an example of this. OpenGL ES 1.1 was preceded by version 1.0. The new functionality includes better support for multitexturing, automatic mipmap generation, vertex buffer objects, state queries, user clip planes and greater control over point rendering.
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