type is supported at present. The attached osgparticleshader.cpp will
show how it works. It can also be placed in the examples folder. But I
just wonder how this example co-exists with another two (osgparticle
and osgparticleeffect)?
Member variables in Particle, including _alive, _current_size and
_current_alpha, are now merged into one Vec3 variable. Then we can
make use of the set...Pointer() methods to treat them as vertex
attribtues in GLSL. User interfaces are not changed.
Additional methods of ParticleSystem are introduced, including
setDefaultAttributesUsingShaders(), setSortMode() and
setVisibilityDistance(). You can see how they work in
osgparticleshader.cpp.
Additional user-defined particle type is introduced. Set the particle
type to USER and attach a drawable to the template. Be careful because
of possible huge memory consumption. It is highly suggested to use
display lists here.
The ParticleSystemUpdater can accepts ParticleSystem objects as child
drawables now. I myself think it is a little simpler in structure,
than creating a new geode for each particle system. Of course, the
latter is still compatible, and can be used to transform entire
particles in the world.
New particle operators: bounce, sink, damping, orbit and explosion.
The bounce and sink opeartors both use a concept of domains, and can
simulate a very basic collision of particles and objects.
New composite placer. It contains a set of placers and emit particles
from them randomly. The added virtual method size() of each placer
will help determine the probability of generating.
New virtual method operateParticles() for the Operator class. It
actually calls operate() for each particle, but can be overrode to use
speedup techniques like SSE, or even shaders in the future.
Partly fix a floating error of 'delta time' in emitter, program and
updaters. Previously they keep the _t0 variable seperately and compute
different copies of dt by themseleves, which makes some operators,
especially the BounceOperator, work incorrectly (because the dt in
operators and updaters are slightly different). Now a getDeltaTime()
method is maintained in ParticleSystem, and will return the unique dt
value (passing by reference) for use. This makes thing better, but
still very few unexpected behavours at present...
All dotosg and serialzier wrappers for functionalities above are provided.
...
According to some simple tests, the new shader support is slightly
efficient than ordinary glBegin()/end(). That means, I haven't got a
big improvement at present. I think the bottlenack here seems to be
the cull traversal time. Because operators go through the particle
list again and again (for example, the fountain in the shader example
requires 4 operators working all the time).
A really ideal solution here is to implement the particle operators in
shaders, too, and copy the results back to particle attributes. The
concept of GPGPU is good for implementing this. But in my opinion, the
Camera class seems to be too heavy for realizing such functionality in
a particle system. Myabe a light-weight ComputeDrawable class is
enough for receiving data as textures and outputting the results to
the FBO render buffer. What do you think then?
The floating error of emitters
(http://lists.openscenegraph.org/pipermail/osg-users-openscenegraph.org/2009-May/028435.html)
is not solved this time. But what I think is worth testing is that we
could directly compute the node path from the emitter to the particle
system rather than multiplying the worldToLocal and LocalToWorld
matrices. I'll try this idea later.
"
bool observer_ptr<>::lock(ref_ptr<T>&) to avoid the temporary ref_ptr<>'s
being created and destroyed on the stack along with the associated ref/unref() operations
META_OSGMANIPULATOR_Object macro to ensure these classes could work
with their wrappers, and a few naming styles should be changed as
well. Fortunately everything seems to compile fine under Windows and
my new Ubuntu system.
And I finally find the problem of the
serializers/osgTerrain/Terrain.cpp, it just missed an "osg::Group"
before "osg::CoordinateSystemNode" indicator. With the small fix
attached now VPB could generate terrain with osgt/osgb formats."
- compile errors on windows when compiled with UNICODE flag
- warnings for duplicate WIN32_LEAN_AND_MEAN. I think this should
better fixed by adding WIN32_LEAN_AND_MEAN to vcproj preprocessor
list."
modifications of the osgShadow header naming styles as well. The
osgDB::Serializer header is also changed to add new Vec2 serializer
macros because of the needs of osgShadow classes. It should compile
fine on both Windows and Linux. But I have only done a few tests to
generate .osgb, .osgt and .osgx formats with these new wrappers."
few headers and the osgAnimation sources are also modified to make
everything goes well, including:
A new REGISTER_OBJECT_WRAPPER2 macro to wrap classes like
Skeleton::UpdateSkeleton.
A bug fix in the Seralizer header which avoids setting default values
to objects.
Naming style fixes in osgAnimation headers and sources, also in the
deprecated dotosg wrappers.
A bug fix for the XML support, to write char values correctly.
A small change in the osg::Geometry wrapper to ignore the
InternalGeometry property, which is used by the MorphGeometry and
should not be set by user applications.
The avatar.osg, nathan.osg and robot.osg data files all work fine with
serializers, with some 'unsupported wrapper' warnings when converting.
I'm thinking of removing these warnings by disabling related property
serializers (ComputeBoundingBoxCallback and Drawable::UpdateCallback),
which are seldom recorded by users.
By the way, I still wonder how would we handle the C4121 problem,
discussed some days before. The /Zp compile option is set to 16 in the
attached cmake script file. And is there a better solution now?"
