Use M_PI (and friends), where possible, in favor of hand-coded
approximations of various (in)accuracies. Where that's not available
(e.g. fragment shaders), use the same value that qmath.h uses for
M_PI, for consistency. Replaced math.h with qmath.h in places that
defined a fall-back in case math.h omits it (it's not in the C++
standard, although M_PI is in POSIX); or removed this entirely where
it wasn't used.
Reworked some code to reduce the amount of arithmetic needed, in the
process; e.g. pulling common factors out of loops. Revised an
example's doc to not waste time talking about using a six-sig-fig
value for pi (which we no longer do) - it really wasn't relevant, or
anything to be proud of; nor did the doc mention its later use.
Task-number: QTBUG-58083
Change-Id: I5a31e3a2b6a823b97a43209bed61a37b9aa6c05f
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Also make the fragment shader a bit simpler
Change-Id: Ie50940da0a4f896504c9f5962cdb6c455983302f
Reviewed-by: Laszlo Agocs <laszlo.agocs@theqtcompany.com>
On systems that give alpha configs by default writing alpha values of
less than 1.0 is a bad idea since it will lead to the content behind the
window becoming visible, even though this is not the example's intention.
Change-Id: I23cdfc1fb78d77b1cbc192d2aba5d6665a7acfcc
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
[ChangeLog] Added QOpenGLWindow. This serves as a convenience class for
creating windows showing OpenGL content via an API similar to QGLWidget
and without any widget dependencies.
Done-with: Jorgen Lind <jorgen.lind@digia.com>
Task-number: QTBUG-36899
Change-Id: I52e9bc61acb129dbfd3841b3adeffab2dbcf7f05
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
