Fix build on QNX

There is std::isnan and friends, but math.h also defines isnan as macro,
so std::isnan expands to std::whateverthemacrois and that fails to build.
So include math.h early on, get rid of the macros and then we can continue
to use std::isnan throughout the code base safely.

Change-Id: Ifee580fa2adff396eb6d6f064d4c095a896fb022
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>
Reviewed-by: Fabian Bumberger <fbumberger@rim.com>
Re-enable JIT

Ooops, an earlier commit accidentally disabled it.

Change-Id: I7b732e0addba8b6403e0d6818d784f267711af42
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>
Fix QSGSimpleTextureNode's dirty signals for atlas textures

When used in an atlas, changing the texture also changes the
geometry.

Change-Id: I744eb0ef58aed9f3a5e51ea89c4da1fad5824633
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
Public API for creating atlas textures, when available.

Atlas textures are currently only used when scenegraph is
combined with the customcontext from the playground/scenegraph
module.

Change-Id: I42f62abdad42e97cc1dcdc05bfb16ecf2839dc0e
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
Don't set opacity when we are not told

Change-Id: I8addc16f37ad9ce431a3b7b2fd1a4884693d7e38
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>