Gravity effects just about everything, including light. Being the nut
that I am, I enjoy messing around with super masses (when writing) which
has lead me to ask thus if anyone has had parallel thoughts. Would most
likely cause the average PC to melt to create the effects in real time.
Anyway, just a bit of random thought, tear it to shreds.
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It’s not too clear what your idea is. Are you talking about simulating
the bending of light due to gravity?
If so, you may be able to use shaders and postprocessing to get a rough
approximation, in some cases, of what an observer would see in terms of
However, a proper simulation of global illumination with gravitic
lensing and such would probably mean simulating individual photons as
actual particles that do not travel instantly, instead of rays… Or
perhaps turn the rays into parametric curves in space, if there’s a way
to easily know the trajectory a photon will take when subjected to
gravitational sources of different shapes and intensities.
It’s been done, though not in real time:
With a raytracer this is a trivial problem, but with rasterization it
sounds pretty complex, if not impossible.
As a fake solution, I suppose if you treat each pixel on the screen as
an atom (a single, floating particle), then you could manipulate (twist,
swirl, and stretch) those atoms around your gravity wells. Draw the
scene once normally, then again to manipulate the frame buffer results
in a fragment shader. You could calculate the distance of each pixel to
the gravity well (whose positions are supplied as fragment parameters)
and then given some time T (another parameter), you could project where
the pixel should have been (distortion). This is very simple at best,
with a lot of issues still to be addressed (such as missing gaps
Wow, it seems I was answered. I can sort of see how this would work for
something such as the black hole/superstar orbit near starburst galaxy
M82, I guess my real question is the possibility of an object with a
gravitational field moving (in relation) at high speed past what could
said to be (in relation) spot lighting.
Why might you ask? The theory of existents of life forms living within a
high gravity well, who with being able to surmount the barriers of this
well, have found them selves in a such relatively low-gravity realm that
their DNA structure begins to crystallise in the relative micro-gravity.
Thus following with weaponry to be of such compressed mass that the
projectile would bend light in its passing.
There are “light-bending” effects in several recent Valve games - for
instance, if you’ve played Portal, there is a slight (hard to notice)
bending effect when you open a portal, also in the Half-Life 2 games
when a strider fires its big laser gun (not its normal gun) there is
first a “sucking” effect where light appears to be bent around the
strider. Maybe other games have something similar, too. So it’s possible
to do some light bending effects in real time, but it’s not anything
like an actual general-relativistic simulation, just a hack that looks
good. Still, I bet you could implement your projectiles this way and no
one would know the difference.
It seems that I have never played the games thus mentioned. For your
examples. are they both from stationary objects? If so, then question is
how it would react whilst in movement; I need a Steven Hawkings
incarnate, does anyone have one that I could barrow for this?
it also sounds like a general warp effect, my thoughts go along lines
such as the effects seen when experiencing a solar eclipse, the bending
of light such that it brings into view object that have once been
blocked by such said light bending mass.
They were called “Striders” in Halflife. Here’s a You Tube video on one.
Scroll to the 25th second. The effect simply “sucks in” the surrounding
area and then the projectile is fired off. It’s not really what you’re
after, but it’s a start I suppose.
I don’t see that there would be any technological difference between
doing it on a stationary or on a moving object.
In reading through that which my mind can handle; it seems that it
matters a large amount on the numbers side, something about angle.
Any real physics nuts around here? It looks like we have a hunt.
Oh, and here is a old discussion about something similar that I found:
Okay, if you’re going the full monty and doing a general-relativistic
simulation, then yes it does matter whether the observer and the source
of gravitation are moving relative to one another, or not. However, the
degree to which a gravitational field’s shape changes under motion
depends on how close to the speed of light the motion is. But you want
your light-bending projectiles to move at a slow speed, or the player
can’t possibly see them moving. Thus the effects will be negligible.
Well, I am not sure what the point would be of a gravitational mass
traveling in a parabolic arc; so it should be near enough to the light
speed horizon that the object itself cannot be tracked by the human eye,
only the trailing gravitational effects.
Also, just something to throw out, lets say this object would be moving
at 30% of the speed of light, how much of a Doppler shift would that be?
I know it would be a visible when throwing around such large speed such
as 30% of light, but I am not sure of the effected area.