Bottle breaking, a Glu3d tutorial by G'rar...
This is a pretty advanced Glu3d tutorial, I will do this taking in considering you have a knowledge of 3dsmax but not Glu3d.
First we need to have all our 3d elements
ready, in this case it will be a beer bottle.
It will be filled with a liquid of course.
So we need a bottle with thickness, using
the outside part of the bottle you will make
an object that we will use to create the
pieces of the bottle, from the inside of the
bottle we will make the liquid inside that
we will use for when the bottle ain't broken,
it will be a bit bigger then the inside so it
fits in between the inside and outside of the
bottle (this is the way you have to place
elements when doing liquid in finalRender
the renderer I use), and we will have a cap
and a cylinder about the same size we will
use for reaction with the liquid since the
cap as to many faces an would make the
liquid calculation insane, so make sure you
use objects with low poly count.
Now that we have our basic elements we
will take care of breaking the bottle apart,
first make a copy of the outside bottle cause
we will need later as a container for the
Glu3d liquid to settle in. We will now create
a PArray and use the copy of the outside
bottle as a Based Emitter. make nice big
pieces, around the neck of the bottle the
pieces will be smaller as long as the main
body of the bottle are big since beer bottle
often break in big pieces, and the smaller the
pieces the longer the liquid will take to
calculate. Once you have what you want, take
a snapshot of the pieces at frame 0 so they are shaping the bottle and not exploding, cause we only use the PArray to do our fragment
and not for the actual animation cause PArray is to limited. We will use Reactor, I just gave the pieces some dynamic properties and then
let them fall to the ground, changing a few things until I got something I liked. I'm not going in details since this is a Glu3d tutorial.
So you will get something like this, now our animation is almost
finish we need to have the bottle intact for a few frames, so for
around 15 or 30 frames our bottle will stay intact, so add a visibility
track and make the bottle visible for that amount of time, and then
make it disappear when the animation starts, do them same for the
liquid since we will replace it with a Glu3d liquid. Now we need one
last thing before we can start the liquid part of this tutorial, we
need to link the beer cap ref to the actual cap so it follows the same
movement. For the liquid part we will need the cap ref, the outside
bottle and the pieces that appear white on the image, the rest you
can hide cause we won't need them.
Ok now we will start the glu3d part so I will try to go in details for this section, and try to explain as much as I can as I go.
First we need to fill our outside bottle part so lets keep only that for now, make sure you name your selection of big pieces, the white
part in the previous image. Now go in create/glu3d pouring system and click the glu3d button, it will make our glu3d elements appear
and a new menu bar, the glu3d toolbar.
Now we will prepare our Glu3d elements to fit with
our scene, first of all press the Enable/Disable the
Glu3D Clip-box, we need to resize it to be around our
bottle explosion, all particles coming out of this box
will disappear. Then select the floorGlu3D and resize
it to be around the same size as your Glu3d Clip-box
and move it just under the bottle outside object so
you get something like the image on the right. Now
unhide your bottle pieces selection and your beer
cap ref, select them with the Outside bottle and
press the Open the Object Manager it will open a
new window, and you will press the Add selection
to list button, in the list select all the pieces of broken
bottle and the beer cap ref, and enter the following
in the Dynamic params. Under Collision GAP enter
0.001 this controls how far particles collide with the
pieces and cap sides. Enter 0.3 in the Bounce, this
controls how particles bounce when colliding with
interacting objects. Enter 3.0 under Friction, this
like it says controls the friction. And under Adherence
enter 0.0 this controls the "glueness" effect of the
.
Object, I left it at 0 cause beer doesn't really sticks to glass. Put the Bounce at 1 and Friction at 3 for the floorglu3d. Leave the Outside
bottle as is. Here's the object manager so you can understand better.
Now that the dynamic parameters of our objects is all set close the object manager and we can fill up the Outside bottle. First select
the glu3dparticle, keep the radius and rate, since it controls the number of particles and the speed of the particles we don't need to
change it since we are filling up an object, so leave them as is, change the LOD to 3, this is the resolution of the solver the higher the
resolution the more details you will get in your liquid but the longer it will take to calculate, 3 should be more then enough and quick
enough to calculate, I prefer to leave this one lower and raise the one on the surface. Then change the thickness to 6.5, this is a kind of
viscosity parameter for the liquid, the higher you put this the more your liquid will become like jello. You
might change these setting often before you get the effect you want. Now we will fill the Outside bottle,
under the source type select Object filled, it will open a selection window, select the outside bottle object,
I normally save at this point. It will fill your object with particles, set the FIlling % to 97 so the outside bottle is
not full to the top otherwise particles might escape, then you need to settle it, so press the HOLD TIME button
it will open a new window and start calculating, when you are satisfy with the result you can press the stop
button. I normally let it settle for 20 to 30 frames before you press the stop button it, but in this case 1 frame
is more then enough since we use visible tracks to pass from the mesh liquid to the glu3d surface. So once
this is done hide the outside bottle, and unhide the beer cap ref, the broken pieces selection we did before,
the floorGlu3D and the Glu3D Clip-box in other words all objects interacting with the glu3dparticle, cause
hidden objects don't interact even if they have dynamic parameters set to them. You should get something
like the image below. Now would be another very good time to save since the next step takes long to
calculate. Now that everything is ready we will press the Calculate glu3d button and be patient or even go
take a coffee this is long. All depending on your parameters.
Back from my coffee, the calculation is over and we have our particle animation. You can stop the calculation anytime if you see it's not at all
what you wanted, while it calculates you can move the slider to see frames that were calculated already, the advice I give you is make test
with LOD of 1 to give you a rough idea of how stuff is reacting, the particle part of glu3d is very long but very impressive results. Now that
it's done we will start the glu3d main node part, the surface in the scene known as the Glu3d_# (normally 01) this will be our surface mesh
of the liquid, to see a preview of the present frame press the Hide/Show the polygon surface mesh button, that way you can play around
with its Surface Parameters before making the final calculation this time of the surface mesh animation. So here we will put the Surface
LOD at 14, the higher the value the more polygons you have and of course longer to calculate but nicer at render, Drop Size we will lower
at 3.5 this we get smaller details since it's the radius of particle, Melting treshold is how particle blend together depending on their spacing,
the higher this value the further apart particles will blend together and will give the illusion of making the drop size bigger, you will also get
different effects depending on the Drop Size to, here we will set it at 6 and the Shrink Wrap at 0.55, this value varies from 0 to 1, 1 given a
more pointy effect to the mech while 0 will make the mesh rounder.
Now that you know exactly what your liquid will look like you can test a few frames to be sure, or if you're not satisfied you can always
press the flush/delete particles button that will delete your particle calculation and then change your dynamic parameters in your glu3d, or
even change your gravity in the main node (glu3d_# object), and then recalculate until you get what you want, in this case we are satisfied
so we will once again save, and then press the Build Surface button, it will pop a window like for particle calculation but now it's much
faster to calculate. And then voila! you are done.
Here is the animation with, lighting and labels, 5.2mb in QuickTime: