bugle-error — detect errors in OpenGL calls
This filter-set does not take any visible action on its own, but provides a service to other filter-sets. It calls glGetError(3) after every OpenGL call to detect OpenGL errors (it does not detect X errors).
Usually you will not need to explicitly load this filter-set; if
you want to be informed of OpenGL errors, either use the
showerror filterset, or
gldb-gui(1). However, you may
occasionally see the message
An OpenGL error was detected but will be lost to the application.
This means that bugle's internal
error-checking code accidentally collected an error caused by one
of your calls, and thus if your application later called
it would not be informed of the error. However, if you add the
error filter-set, it will catch the error
first and your application will be correctly informed of the
Because the error reporting semantics of OpenGL are not completely defined (in particular, an implementation may choose how many error flags it has), it is impossible to guarantee that this filter-set is completely transparent to the application. However, the first call to glGetError(3) always return an error, and in practice this is all that is necessary.