Removed Functionality

The features that were removed from OpenGL are described in in Appendix E of the OpenGL 3.2 Core specification, and you should use that as the definitive guide for the changes you need to make in your application. Here is a summary of most significant areas that changed:

• If your application uses the fixed-function pipeline, it must be rewritten to use shaders instead.

• If your application uses shaders, you must rewrite your shaders to use OpenGL Shading Language 1.5; many built-in shader variables provided in earlier versions of the OpenGL Shading Language were explicitly removed from the OpenGL Shading Language 1.5 specification. Similarly, your application may no longer provide vertex data using the fixed-function routines; all vertex attributes are now specified as generic vertex attributes.

• Your application must explicitly generate object names using the OpenGL API.

• Vertex data must be provided to OpenGL using buffer objects.

• The built-in matrix stack functionality from earlier versions of OpenGL has been removed; you must recreate this functionality using shader inputs.

• Support for auxiliary and accumulation buffers has been removed; use framebuffer objects instead.

• Your application no longer fetches the list of extensions as a single string. Instead, you first fetch the number of extensions and then separately fetch each extension string.

Extension Changes on OS X

OpenGL 3.2 provides functionality that earlier versions of OpenGL provided through extensions. Other extensions that were previously supported on OS X are no longer supported when your application uses the OpenGL 3.2 Core profile. Table B-1 lists extensions described elsewhere in this guide; use this table to determine whether the extension is supported, and if not, what equivalent functionality is supported.