My final project for VEF1 Class. I intended on having a catapult launch a cannon ball at the castle below. But the catapult completely miss the castle and the cannon ball overshoot the castle and lands onto a field next to the castle. I created a soft body on the field where the cannon ball lands, so the field will deformed. I used the gravity and the drag fields from Maya to achieve my effects. The gravity field is so the ball will fly at a nice arc when being launch from the catapult. The drag field is so my cannonball will come to a stop when land in the grass field. I used Lambert and Mia Material X as my shaders, and I created all my textures in photoshop. I used the Maya physical Sun and Sky as my lighting, to give the scene a natural outside lighting system. Then I rendered it out with Maya Mental Ray and composited my shots into After Effects. Due to the limited time, I wished I could have work on this project for another week to really polish it up, maybe changing the field into a forrest.
VISUAL EFFECTS 2
Project #1
I want to create a flamethrower simulation into Maya.
Flame comes forward and upwards when coming out of the
flamethrower.
I plan on creating a 3D container with emitter
I want to test the 3D container by setting up the base
resolution to be around 50 or 60. Then I plan on setting up the container to be
long lengthwise
For the flame, I want the flame to be coming out from one
side of the bounding box to the other.
When flames come out of a flamethrower, it comes out bright
yellow, almost white. Then the flame becomes bright yellow, to orange, and
finally to red just at the end. Finally, at the end of the flame, black smoke
appear but just very brief.
FluidShape -> Dynamic Simulation -> Viscosity
-
Look up Reynolds Number
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Reynolds number is 0: Viscosity is 1
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Reynolds number is 10000: Viscosity is 0
I found no help on internet to the solution of finding the
Reynolds Number for flames coming out of a flame thrower, it looks like the
nerds at NASA hasn’t figured everything out yet. I ended up using .020 since
that was what most online tutorials used for flames in the fluid simulation.
When setting up the flames in the fluid effect, These are
the biggest adjustments that I have used to achieve the results of my flame.
Substeps: – to
improve the quality of my simulation
Solver: Use
Navier-Stokes (Best solver to be used for fluid simulation)
Density – Scale,
Buoyancy, Dissipation: (the movement of the fluids)
Velocity – Swirl:
(create some stability for my simulation)
Turbulence – Strength:
(the amount of force applied to my turbulence)
Temperature –
Buoyancy, Dissipation: (motion of the simulation, how much pressure and
when the simulation fades away)
Fuel – Reaction Speed
(how quickly the flame shows up in the simulation)
Shading – Glow
Intensity (gives it that glow, only applied small amount)
Shading – Incandescence
(Color of the flame)
I ran into a lot of issues with my fluid simulation, here
are some of the biggest issues I ran into and how I solved them:
Problem/Issue #1:
the demonstration of the flame that was done in class has the flame going
upwards. When flames come out of a flamethrower, it goes forward not upwards.
Solution: I was
able to solve this by just rotating the boundary box sideways. I figured out
this method before the flamethrower demo in lecture 2. I decided to keep this
method because the flames in a flame thrower goes straight in a quick burst and
then faded away, while using emitters in the demo has the flames going
downwards. I probably could’ve made it work, but I figured since it already
working for me, no need to re-do everything to achieve the same results.
Problem/Issue #2:
Flame was coming out of the flamethrower in little puffs; it wasn’t a stream of
flame. The fire appears to be coming from a baby dragon that was just learning
how to breathe out fire.
Solution: After
spending an hour trying to adjust the speed, I realize that all I needed to do
was just adjust the rates inside of the fluid emitter tab
Problem/Issue #3:
I was struggling to get the flame colors to appear. I had the correct flame
colors in the Incandescence box, but it just wasn’t looking saturated enough.
Solution: After
looking around Google for tutorials on realistic flames in Maya, I noticed that
almost all of them start out with setting up simple lights into the scene. So
once I put in a point light and changed the color to a light yellow, that
solved my problem right away
Problem/Issue #4:
I noticed that when the flame comes out of the flame thrower, It would come out
as this weird mushroom shape, almost like a nuclear bomb mushroom shape smoke.
It didn’t look like the flames in my reference video
Solution: After
researching, I found that that keying the Turbulence strength from a starting
point of 3 at frame 1, and reducing it to .1 on frame 40 has somewhat eliminated
the mushroom shape flame.
Things that I could improve on my simulation, if had more
time:
Issue #1: Very
small area of the flame appears to be cut off. I didn’t noticed this until
after I fully rendered out my video.
Solution:
Increase the size of the boundary box
Issue #2: Flame
isn’t moving as fast as my reference
Solution: Could
increase my settings such as the buoyancy
Project #2
For project 2, I want to create flames coming out of a
dragon mouth.
The reason I decided on creating this effect is so I can
have something that is similar to the Flamethrower effect I created in Maya.
This will allow me to see which application I like better when it comes to
creating flames.
To save time, I plan on downloading a model of a dragon. I
have decided on using the Alduin Dragon model from The Free 3D Models (tf3dm)
website. Sadly, the model rig and animation is only done in Maxon Cinema 4D
program. If I have enough time, I will like to animate the wings and at least
the dragon head as he breathing flames.
To create my fire, I will try to create a sphere, and then
apply the fireball effect from Houdini Pyro Shelf and see if that work. After
playing around with Houdini Pyro, I have decided the Flame should work great
for this project. I also tried explosion and could tell right away that the
effect wasn’t going to help me, so that how I decided to go with the flame
preset.
My first effect that I wanted to achieve based on my
reference is to get the flame to build up in size as you can see in my
reference. I used the Gas Released inside of the Combustion tab in the pyro
solver node. What I did was set it up to 14, keyed it. Then I went ahead to
frame 85, changed the value to 100 and key it. Then I went to frame 105, and
change the value to 100 so the fire keeps getting bigger and bigger. Finally I
went to frame 130 and set the value to 0 and keyed it. However, due to limited
time, I wasn’t able to render out that many frames. I will explain in the
problems/solution area below.
To set this up, first I created a sphere, and then I applied
the Flame from Pyro to the sphere. Houdini automatically created some nodes for
me. So first thing I wanted to do was set up the container and the direction of
the flame. So inside of the pyro node, I set the size up to be 70 units long,
and the height and wide to 50 units. (After rendering out the scene, I have a
feeling that I made my boundary box way too big and it really killed my
rendering time; will have to research more into this) Next I went into the pyro
solver node, the simulation tab, and I set the buoyancy direction to 5/0/0 so
that the flame will go forward and not upwards. Then I set the buoyancy lift to
9 to give the flame some push. Next, I went to the combustion tab, and use this
tab to set up the flame simulation. As above, I used the gas release in this
tab as well as the burn rate. I set the burn rate to .99 to really get the fuel
to burn. Then, I went into the shape tab, which is used to adjust how the flame
looks. I checked on all the boxes except the confinement and made some
adjustment to each of different options to get the flame to match the reference
as close as I can. Finally, to get everything to look great, I went into the
shop mode. Inside there I was able to adjust the color of the smoke and the
flames. I wanted the smoke to be black and not so gray, so into the color tab,
and just change the ramp color on the right from white to gray. Next I went
into the density tab, and adjusted lookup ramp in the float setting to give the
smoke some sharpness. Next I went to the fire tab, into the color area, and
adjusted the ramp colors to make the flame look more realistic. I have added
about 15 colors into the ramp to really give it the flame look. However, at the
end of the render, my colors looked really blown out. I will have to research
more to find out why that happened.
I ran into a few issues with this project.
Issue #1: My
biggest issue happened on Friday night, my Houdini quick render preview decides
to stop working. For whatever reason, it wouldn’t render anything. When I press
the render icon, nothing happens. So I tried to set up a render node with
Mantra PBR and batch render a few frames and even that didn’t work. So I took
my laptop to a Professor and asked him if he knew what was wrong with Houdini,
but no luck he couldn’t figure it out. So I took my laptop to Ari, the lab
instructor and see if maybe she would know what wrong but she couldn’t figure
it out either.
Solution: So
finally, I figured the problem out late last night on Saturday. It turns out
that I had to manually enter in my License keys in the license administer tool
inside of Houdini. I wasn’t sure what happened but this probably is the most
frustrated experience since I been attending to Full Sail, it took me over 2
days to fix the problem.
Issue #2: My
render take way too long. Everything would work smoothly until it gets to Frame
100 and then the simulation would really start chugging. Sometimes taking up to
20 minutes pre frame
Solution: None so
far, but I think it has to do with the gas release keep building up. I also
think it has something to do with the boundary box size as well.
Since Houdini License issues have really held me up, I
didn’t have much time to work on this project. So since the rendering took
forever, I have decided to just render out the flames, and then take the dragon
and rendered it out in Maya and import both of the renders into Nuke and
composite them together. I figured since I was already in Nuke, I would add a
background.
Overall, I have learned a ton about Houdini Pyro; I just
didn’t have much time to show for it. If I could just have an extra day or 2, I
really could polish this thing and end up with a much better looking fire, or
at least a higher quality. I am considering taking up VFX as my career, so that
why I am just so disappointed in this project, just because I can’t figure out
how people can achieve very realistic results and I can’t even figure out how
to render. No one going to want to hire a VFX guy who can’t even do fire. But
in my spare time, I will be pushing myself to create the best realistic fire
and explosion that I can possibly create.
I can’t really say if I like Maya or Houdini better with the
flame since I ran into a lot of issues with Houdini license issues and it
wouldn’t be fair to say Maya is better. But since we have been using Maya for
over a year now and just touch Houdini last month, Maya is the more comfortable
option. But however, I seen some really cool videos of people using Houdini to
create some AMAZING explosions that I
doubt if Maya can even get close to that level of quality.
Final Project
For my final project, I want to
create green slime falling onto a helicopter. I got the idea from the TV
station Nickelodeon. They had a TV show called Figure it out where they dump
green slime on the contestants. There
really isn’t any reference on it. Here is an
idea of what I want to achieve, but with a helicopter instead of people.
First step is finding a really cool
helicopter for this project, which I found on The free 3d model website, http://tf3dm.com/3d-model/uh60-helicopter-47194.html
. Once I imported the Helicopter into Houdini, the first thing I wanted to do
is have the rotors blades rotate as the slime is falling on it. But when I imported this model into Houdini,
it was one solid object. Since my Houdini modeling skills isn’t great, I
decided to open up the helicopter in Maya and break it down into separate parts
so I can bring it back into Houdini. But to my surprise, the person that
created this model has already broken it into parts. So I brought the model
back into Houdini and decided to research and see if there is a way to break
this thing down. I did found a solution in my research, which involves using a
connectivity and partition nodes. How it works is first I attach the
connectivity node to the helicopter node, go to the attributes and named it
“blades_$class”. Next I attached the partition node into the connectivity node,
go to the rule and put in the same name as I did for the connectivity node
“blades_$class”. Finally, in the group menu, it has all the groups that were
created in the model by the creator. I used the “main_rotor” group, since this
is the blade that I want animate for my project. Finally, I attached a
transformed node, make sure that the group was set to “main_rotor”, and
animated the rotate. For frame 1, I had the rotate set to 0 and in frame 120; I
set the rotate to 2120.
Next, I want to get the green slime
added into the scene. I wasn’t sure how to get this effect to work, so I did
some research and determined that using a sphere would be the best solution. So
first, I created the sphere, and made sure that it was above the helicopter.
Next, I went to particles fluid shelf, and attached the emit particles tool to
the sphere. When I played out the simulation to see what happens, I noticed two
problems right away. One is that the fluid goes through the helicopter and the
other probably is that the fluid moves way too fast for slime. The first
problem is easy, just by making the helicopter a static object from the rigid
bodies shelf. The second problem took me some time and research. After
researching this problem, I found out that I could apply the viscosity to the
fluid emitter. I applied the make viscosity in the Auto Dop Network node,
connected it to the Flip Fluid Object node. This will give me the viscosity
control that will allow the fluid to be slower, similar to honey or slime.
When setting this project up, I
have learned my lesson from the Houdini Pyro and didn’t make the container so
huge. So at first, I made the container the same size as the helicopter, but
once I ran the simulation, the particles would disappear when going outside the
box. I want the box to be just big enough so it doesn’t kill my render time,
yet keep all the particles visible. The best way that I could think of to do
this is by moving the camera close to the helicopter and then make the boundary
box just big enough to cover the camera view but doesn’t go outside of the
view. Then I noticed that when running the simulation, the slime would hit the
helicopter and then keep going through the bottom, I thought about just leaving
it like that and taking the render files into Nuke and putting in a sky, but I
decided a ground plane would work better. For my settings, I went into the Flip
solver to set up the boundary box that I mentioned above. For the resolution,
of the particles, I went into the flip fluid object node and decreased the
particles separation. However for the simulation test, I increased the number
so that it doesn’t take a long time to see if the effect works or not. Next, to
even improve the simulation speed even more, I went into the Guides tab of the
Flip Fluid Object node, and went to the particles tab. Inside there, I changed
the visualization from sprites to particles. Then the last area I went into to
adjust my settings is into the Physical tab of the Flip Fluid Object node. I
reduced the bounce and the friction to zero, since this is suppose to be a
heavy slime. Then I upsize the density to 10,000 to make the slime more thick
and not so thin. Finally, I cranked up the viscosity setting to 10,000 as well
to give it the slow moving slime look.
Once I have my settings all set up
and I am happy with how the slime look, I noticed one more issue. It looks like
the slime was going through the blades as it was hitting the helicopter. I was
hoping that I could fix this issue inside the fluid settings, but I couldn’t
get it to work. After thinking about this issue, I realize that I could make
geometry invisible to render and also invisible to the viewport as well. So I
just created two different cubes, applied the transformer node. Inside the
transform node, I adjust the size of the cube to match the blades. I also added
a little thickness to the cubes as well. I also applied static object to both
cubes so that they will interact with the slime as it hit them. Then used the
same keys from the rotation inside the main rotors and applied them to the rotation
of the cubes. I did this by going to the main rotors, copy the rotation
parameters, and then went into the cubes rotation and pasted copied relative
references. That way if I make any adjustment to the main rotor rotations, it
will automatically applied my adjusts to the cubes as well. In my turn in
folders, you will see two flipbooks. One has the geo invisible and the other
you can see the geo.
Finally, once I was happy with the
look of the slime, and the helicopter rotors rotations, the only thing left to
do is apply some lights. I used three different lights for my scene. I used one
environment light and two spotlights. For the environment lights, I did use an
IBL but decided not to. For the light colors, I picked a light blue with about
.41 in the light intensity. For the spotlights, I used the same settings for
both lights. I picked a pure yellow color and really low in the light
intensity, I have them both set at .29
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