It is now optional to give a Camera object when constructing a View. If
a Camera is not specified, one is automatically set up by calling
ResetToBounds on the spatial bounds of the scene.
This makes it even easier to set up a view.
Also implement pan and zoom for 2D cameras.
Update the rendering tests to do these camera rotations. This matches
better the viewpoint used before the previous camera changes.
Affine transformations of homogeneous coordinates using 4x4 matrices are
quite common in visualization. Create a new math header file in the base
vtkm namespace that has common functions for such coordinates.
Much of this implementation was taken from the rendering matrix helpers.
Render interface consistency
These changes mostly represent changing the interface to some of
the rendering classes to be more consistent with the reset of VTK-m.
In particular, several exposed class members become private and
are accessed through methods.
There are some other changes to make the interface simpler to
use. One example is consolidating the width/height of the image
to the Canvas. (All other classes refer to the Canvas for the
width/height). Another example is removing the template from
the View class.
See merge request !442
I do not have OSMesa on my main development platform, so I missed updating
some of the code when I changed the interface.
Also removed some inline statements on pure virtual functions that GCC
was complaining about.
Most of the time, you just match the WorldAnnotator with the canvas of
the same type. Rather than make the user specify it every time, add a
method to the canvas that creates a "good" WorldAnnotator to use with
it. Then, if a WorldAnnotator is not given to the View constructor, one
is automatically created from the Canvas.
The template parameters on vtkm::rendering::View are unnecessary. All
three of the templated classes are polymorphic (with virtual functions).
Thus, you just have to specify them at the constructor. Removing the
template parameters makes the syntax a bit cleaner and removes some
unnecessary duplication in the executable.
Removing the template does mean we cannot optimize in the future.
However, I expect us to start using more virtual methods rather than
less, so I think this is a move in the right direction.
With only a few exceptions for simple structures, we do not expose the
members of classes. Instead, we provide accessor methods. Do this for
Camera as well as add some helper methods.
The width and height are maintained out of necessity by the canvas. A
second copy was maintained by the camera, which was only used for
computing the aspect ratio and similar metrics for projections.
Having to maintain the width/height in two places is a bit of a hassle
and provides the opportunity for bugs if they get out of sync. Instead,
have the width/height managed in one place (the canvas) and pass them as
parameters as necessary.
Move some of the management of the width, height, and buffers to the base
Canvas class. Also, when it makes sense, get the width and height from
the rendering system.
Also changed the color buffer to be a Vec so that you don't have to
manage array offsets by hand.
All of these changes snowballed from the observation that the glut
example did not properly enable the depth buffer.
Generally we try not to expose the implementation details of how things
are stored in objects.
Also changed some arguments that should have been declared const to
actually be const.
Fix use of uninitialized invSpacing value in volume raytracing
The SamplerRect worklet had an error where it was possible that the
invSpacing stack-local values could be used uninitialized. On the first
iteration of the loop in the SamplerRect operation, it calls LocateCell,
which is supposed to set invSpacing. Under most conditions it does, but
if one of the ray directions is 0 (which can happen with axis-aligned
views), one of the invSpacing dimensions was skipped, leaving the value
to whatever garbage happened to be on the stack. Later, the invSpacing
value was used to interpolate a scalar, which under some circumstances
could cause an array index error when looking up a color in the color
map.
This fix changes the condition for when the ray direction is 0 to still
initialize invSpacing.
See merge request !441
The SamplerRect worklet had an error where it was possible that the
invSpacing stack-local values could be used uninitialized. On the first
iteration of the loop in the SamplerRect operation, it calls LocateCell,
which is supposed to set invSpacing. Under most conditions it does, but
if one of the ray directions is 0 (which can happen with axis-aligned
views), one of the invSpacing dimensions was skipped, leaving the value
to whatever garbage happened to be on the stack. Later, the invSpacing
value was used to interpolate a scalar, which under some circumstances
could cause an array index error when looking up a color in the color
map.
This fix changes the condition for when the ray direction is 0 to still
initialize invSpacing.
There was an error in the CMakeLists.txt in the rendering tests where
the include directory was linked in instead of the OSMesa library.
It was a simple mistake of typing the wrong CMake variable.
Rename rendering classes
Per our discussion in our last technical meeting, we are renaming several
of the rendering classes to be more clear and consistent with other
software products.
See merge request !437
Without a working directory specified, the executable will be output
to what-ever working directory cmake-gui was launched from. In most cases when
CMake is the 'system' version, this is a directory that you don't have write
access to.
The word surface is more often used for something like a polygonal mesh,
so this name is quite confusing. Canvas is consistent with a
conventional name in GUI widget APIs.
The rendering classes do not actually manage windows, and window was not
descriptive of what this class was doing. We decided that the class was
mostly analogous to what we call a "view" in ParaView.
For header files, this only adds the file to IDE file lists, which is
convenient but not critical. However, the test did find a ligit error in
the hello_world example where the TBB build was actually using the
serial device adapter.
The benchmarking header files were not listed. Not a huge deal since
these files do not need to be installed, but they should be listed
anyway. Changed the vtkm_save_benchmarks CMake macro to be able to list
headers.
Also moved everything from BenchmarkDeviceAdapter.h to
BenchmarkDeviceAdapter.cxx. Since this code shouldn't need to be
included by anything except this benchmark, there is no need to have it
in a header file. Plus, the build changes would mean that any change in
the header (where most of the source was) could cause all code in this
directory to recompile. I do not want to set that precedent.
The test is a simple CMake script that finds all files in the build
directory with certain extensions (.h, .cxx, etc.) and makes sure that
the filename is listed somewhere in the CMakeLists.txt file of the same
directory. If the filename is listed in the CMakeLists.txt file, then
there is a good chance it is being addressed by the build.
This should help catch when header files are not being installed. It also
should help verify that test builds are being done on all files. It will
also highlight dead source files.
Not all systems put their OpenGL headers in a directory named GL. (In
particular, OSX decides to be different.) The vtkm/rendering/internal/
OpenGLHeaders.h header takes care of including the OpenGL header on all
platforms.
This is required for installing the files. It is also useful for
developers because it adds the files to IDEs and creates test builds for
the header files. Those test builds highlighted some missing includes.
Adding text annotations to rendering
This adds bitmap font support and two types of text annotations - screen space text and world-space billboard text - as well as enables the labels in the axes.
See merge request !423
