Related: de
sign,
hard,
host,
mass,
pressure,
source,
space, speed,
temp,
time,
virtual, visco, volume
The
physical
universe is dualistic:
virtual/
physical
spiritual/
temporal
de
sign/
build
type/
instance
code/
host
DNA/
dust
Physical
sources are the
rivalrous,
material aspects of
reality such as
space,
time,
mass and
energy required to
host (store and express) virtual
things.
OpenSourcePhysics.org
* The de
sign of a table may be held in a brain, then probably written on paper or with
CAD software, and eventually constructed with
tools,
wood, and
skilled
labor.
* A
play writer ex
presses
ideas onto paper with ink and
skilled
labor.
* Paper, ink,
light and
reading ex
press a
play to an
actor.
* An
actor, his
skill and
labor and the
food he ate ex
press a
play to an
audience.
Changing a
virtual re
source usually implies you are
changing a *
copy* of it.
Copying
virtual re
sources is never zero
cost, but a the ease and speed
make it seem
unim
portant.
Changing a
physical re
source usually implies you are
changing this specific
instance, so must be more carefully considered.
Material and
Virtual
objects
differ a
cross the
actions of
Consuming,
Changing and
Copying:
Rivalrous: Does this
action diminish the
freedom of others?
(seating)
Exclusive: Does this
action eliminate this
freedom of others?
(eating)
In
finitely repeatable?
(copying organisms or software)
Gravit.SlowChop.com >>Gravit is a gravity simulator which runs under Linux, Windows and Mac OS X. It's released under the GNU General Public License which makes it free. It uses Newtonian physics using the Barnes-Hut N-body algorithm. Although the main goal of Gravit is to be as accurate as possible, it also creates beautiful looking gravity patterns. It records the history of each particle so it can animate and display a path of its travels. At any stage you can rotate your view in 3D and zoom in and out. Gravit uses OpenGL with Lua, SDL, SDL_ttf and SDL_image.
Impulse-Based.de >>The impulse-based dynamic simulation is a new method for the simulation of articulated rigid body systems that I have developed during my PhD. The impulse-based method has some advantages compared to classical methods like the Lagrange multiplier method or the simulation with reduced (or generalized) coordinates. First of all it is easy to understand and easy to implement. It can handle all kinds of joints, velocity constraints, collisions and contacts with friction. The iterative method can even simulate models containing closed kinematic chains without additional effort. The simulation provides accurate results just depending on the used tolerance values. Since the computation of impulses is very easy the simulation runs very fast and even complex models can be simulated in real-time. The Lagrange multiplier method has a drift problem and therefore needs an additional stabilization method like e.g. the one from Baumgarte. The impulse-based method targets a valid joint state directly and so it has no drift problem and no additional stabilization is required.