With the major revision 2.0 of VTK-m, many items previously marked as
deprecated were removed. If updating to a new version of VTK-m, it is
recommended to first update to VTK-m 1.9, which will include the deprecated
features but provide warnings (with the right compiler) that will point to
the replacement code. Once the deprecations have been fixed, updating to
2.0 should be smoother.
There were apparently some fields copy/pasted from the 3D version were
not used in the 2D version (probably because they had no meaning). In
one case, one was erroneously normalized, and could cause a floating
point exception.
The timer class now is asynchronous and device independent. it's using an
similiar API as vtkOpenGLRenderTimer with Start(), Stop(), Reset(), Ready(),
and GetElapsedTime() function. For convenience and backward compability, Each
Start() function call will call Reset() internally and each GetElapsedTime()
function call will call Stop() function if it hasn't been called yet for keeping
backward compatibility purpose.
Bascially it can be used in two modes:
* Create a Timer without any device info. vtkm::cont::Timer time;
* It would enable timers for all enabled devices on the machine. Users can get a
specific elapsed time by passing a device id into the GetElapsedtime function.
If no device is provided, it would pick the maximum of all timer results - the
logic behind this decision is that if cuda is disabled, openmp, serial and tbb
roughly give the same results; if cuda is enabled it's safe to return the
maximum elapsed time since users are more interested in the device execution
time rather than the kernal launch time. The Ready function can be handy here
to query the status of the timer.
* Create a Timer with a device id. vtkm::cont::Timer time((vtkm::cont::DeviceAdapterTagCuda()));
* It works as the old timer that times for a specific device id.
Rather than force all dispatchers to be templated on a device adapter,
instead use a TryExecute internally within the invoke to select a device
adapter.
Because this removes the need to declare a device when invoking a
worklet, this commit also removes the need to declare a device in
several other areas of the code.
Prevously, the x field of view was computed by scaling the y field of
view by the aspect ratio of the canvas. However, this is wrong because
the field of view angles do not scale linearly with the aspect ratio.
Fix this issue by using trig functions to convert the angle to distance,
scale the distance, and then convert back to angle.
The raytracing code has its own version of camera that maintains two
field of view (fov) parameters: one for the x direction and one for the
y. The standard vtkm::rendering::Camera contains only one fov. As is
consistent with OpenGL's gluPerspective and VTK's camera, the fov is
specified in the y direction. However, the raytracing code was
incorrectly using it in the x direction. That caused it to do a weird
rescaling when the aspect ratio was not 1.
Sandia National Laboratories recently changed management from the
Sandia Corporation to the National Technology & Engineering Solutions
of Sandia, LLC (NTESS). The copyright statements need to be updated
accordingly.
