Mini Destrucion Shot by Damiano Moltisanti

Damiano explains all necessary steps for Gg destruction in this complete report about his shot

Inspiration

Looking at the latest catastrophe films, particularly “2012”, I was fascinated by destruction effects of extreme realism with the use of real models and dolly cameras, so I embarked on this challenge to explore and experiment with different VFX techniques in Maya while testing Pulldownit plugin in large-scale destruction, considering all stages to the final shot.

Modeling

All the buildings were modeled from real images, using high-resolution “CG textures” as reference. I projected each texture in a simple “polyPlane” in Maya and I started to add edge loop tool outlining the shapes of the windows and metal structures, following by extracting them ( “extract tool”) from the rest of the plane in order to manage the extrusion of faces separately, thus obtaining a shape on which to work. Then I gave different thickness to walls, glass and windows frames, assigning a reflective shader to glass, a metallic shader for the windows frames and a stone texture for the walls. Once I got one floor done, it was as easy as duplicate it to decide the number of floors per building.

Shattering with Pulldownit

I applied initially an “uniform shatter” in 3 pieces to the walls and pillars of individual buildings, reshatering each big fragment in around 200 pieces again, checking “PDI cut” material option so as to be able to apply the same “stone texture” given to the original faces to the internal ones. Also I created a “quick selection set” to use this selection of faces in the future and made different groups with the fragments to can handle them independently in the PDI basic fractures panel.
For the windows I used “radial shatter” splitting each glass in 10 pieces and increasing the “Shatterit->noise” option to get a more realistic look. Windows frames were shattered in 5 pieces and grouped to be handled separately.

Dynamics with Pulldownit

At this point, I had diferent groups of fragments added to “Pdi basic fracture” panel, so the posibilities of making them break in diferent ways are many. After several experiments with a few pieces, I tried to control the activation of the fragments by placing different “volumeAxisFiels” along the walls and linking them to the PDI fracture groups, also disabling gravity in “PDI solver options” for tweaking the Maya fields only. I had to animate the fields’ magnitude to get a more organic look of destruction. After I was happy with the walls fracture I added the glass and windows frames groups to PDI basic fractures, assigning them a mass value much less than the one of the walls, and Pdi computed the whole destruction set in a short time indeed.

Emitting debris in Maya

After the simulation with Pulldownit was done I made a Maya cache of all geometry, in order to select only the inner faces I used the “quick selection set” I had created previusly. To generate debris only from the pieces that start to activate, I emitted a first stage of “goal nParticles” from the “inner faces” by adding the property “goal” to constraint nParticles to the geometry and subsequently make the “velocity” of the geometry affecting the “lifespanPP” of the particles via “PPexpression”, the “debris” are then generated by new “nParticles” emmited from the first “goal nParticles” and constrained by the attribute “ratePP” velocity of the goal particle.
For instancing the particles as geometry I used again Pulldownit to break a polySphere in 200 pieces, assigning them to nParticles randomizing the scale and the index via “PPexpression”. Finally I activated collision between “nParticle debris” and the outer faces of the cached geometry.

Maya fluids simulation

Maya fluids emission was made in a similar way to the debris. First, I created a fluid emitter from the “goal particle” attached to the “inner face” and constrained by “PPexpression” attribute “ratePP” of the fluid emitter to the “lifespanPP” of the particle goal. In order to prevent smoke from passing through the walls I activated collisions between “fluid container” and “external faces” of the cached geometry.
I did a “fluid cache” setting resolution to “500” for the “fluid container.” This method allowed me to save time in the final calculation because I got a large fluid simulation only with one fluid emitter inside the container.

Rendering & Compositing

This stage of the project was the most time consuming, because of the long rendering times of the buildings and storage space that was often not sufficient due to the large cache file of fluids, I used Mentalray render, illuminating the buildings using a typical “physical sun and sky” and I added glass reflections to the windows using plane projected textures. The explosions of Buildings were lit with an additional directional light.

The smoke of the first building was illuminated using a three-point lighting scheme.
I used Nuke to gather the various render passes and setting up a 3D space scenario around buildings by adding flat projected buildings images to generate a panoramic view of the city. I also corrected several artifacts of smoke rendering by adding more passes but maintaining the original smoke pass as a mask. I tweaked RGB channels to get a good mix of them,  I have to create two different precomp “buildings and simulation” and “background city”, I decide to stress more the second explosion by making a color correction on the two final-precomp nodes, modifying the color of the sky, and also adding a “reflection pass” in the two buildings involved in the explosion to stress the brightness of the glass fragments, and finally increasing overall glow strength.

Conclusions

Making of  “Mini destruction shot” was a great challenge for me,  specially because I had to deal with heavy dynamic scenes using Maya Dynamics and PDI, besides it was a  perfect scenario to learn the pros and cons of various choices that can lead to different results in different computation times, this knowledge will be very useful for me in the future when making bigger destruction sets professionally, I hope so. I think Pulldownit is an excellent plugin for collapsing buildings in Maya, it is fast and able to give satisfactory results in a short time allowing a good control of destruction in a few steps, this tool is evolving better and better really. Thanks to everybody for reading this article and watching my shot, remind to add a “Like” if you like it, of course you can ask me if you need more clarification.

Author: Damiano Moltisanti

damiano.moltisanti@gmail.com
http://it.linkedin.com/pub/damiano-moltisanti/56/400/b06
http://vimeo.com/user12851641

POSSESSED BED by Guillaume Hoffmann

Brief interview with Guillaume about his nice shot Possesed bed using Pulldownit

Why did you decide to make a possessed bed in CG? thats a crazy idea:)
I was looking for a new project involving fracturation/shattering. I had in memory a scene in The Conjuring where a rocking chair is thrown toward the characters, so I though an invisible demonic force would be a good reason to make an inanimate object move by itself and break apart while maybe hitting something.
I had the idea of a bed because it was interesting to mix rigid bodies simulation with cloth.

How did you model and rig the bed?
Actually all the furniture are free 3d models that I found on internet, but I had to re-model the bed because it was too high poly, the fracturation process as well as the simulation would have been too slow and buggy otherwise.
The rig is very simple : the wooden part is only animated with transform nodes : one when it levitates, and two for each part when it breaks. The transition is made simply by animating the visibility of objects.
The mattress, when kinematic, is skinned with two joints that follow the wooden parts, and there is a corrective blendshape.

How did you animate the mattress and the blanket?

The mattress is at first bound to the animation of the bed, the blanket becomes dynamic sooner but still have some points constrained to the same animation. After that it’s all a nCloth simulation with colliders.
Concerning the mattress, I tried a lot of settings trying to have the right behavior but nothing seemed to work. Then I had the idea of simulating only a thin sheet with a large collision distance, with a wrapped mattress model for the final render, and I think that was the best option, moreover it’s faster to simulate.

How did you setup Pulldownit dynamics?

For the long boards on the sides of the bed I used the wood splinters shatter style which was perfect for giving me a crack in the middle. For the front and back panels, I needed a more uniform shattering so I scaled down the panel in one axis, I applied a uniform shatter and then I scaled it back up, which gives similar long wood-looking fragments on all the model.
The piece in the center that breaks first is a fracture object, the two other parts are first a bunch of kinematic or dynamic objects, then it switches to two fractures bodies when it’s thrown at the door.
This last action is perform with a uniform field, it was neat to be able to use it for Pulldownit as well as for the nCloth.

How did you do the transition animation-dynamics for the bed?

Like I said in the rigging part, some objects that are 100% animated switches their visibility with simulated ones. It’s easy to do when the simulation starts when the object is at rest, but for the breaking parts at the top of the bed, I had to make a little script that keyed the state (kinematic to dynamic) of selected fragments at a given frame, as well as setting the initial velocities according to the animation( note: in Pulldownit v 2.7 and later the solver can do this effect by itself).

How did you do interaction between nCloth objects and Pdi objects?

Given that Pulldownit and nCloth can not mutually interact with each other in one solving, I had to proceed by steps.
First of all I made a pdi simulation with only the two remainings of the bed from when it falls back on the ground, and I converted it definely as keyed objects, to keep them for later.
Then I made two simpler models of the fractures and parented them respectively to a foot of the bed to match the overall animation. This is what I used as colliders for the cloth.
Finally I simulated all the smaller fragments, colliding with the geocached mattress, blanket, pillow and keyed / static objects.
To resume the heavier is influencing the lighter : halfs of the bed -> cloth -> small fragments.

Conclusions

The biggest challenge of the project to me was to make interact two solvers that doesn’t understand each other.
I lighted the scene with a portal and an area light but didn’t do a fully realistic render with everything shaded, because I only wanted to spend time on the effects part, which is what I want my speciality to be.
It was my first project using Pulldownit, but I have made some tests on other scenes and I really like the concept of fracture bodies with automatic clustering. There could be some improvements, for example I don’t like the fact that going on the first frame erases the cache, it happened to me a few time by mistake, but Pulldownit is still a young plugin and I’m sure there will be great new features to come.

Author:  Guillaume Hoffmann
https://vimeo.com/user8551736

Wineglass breaking and fluids by Jordi Alavedra

Jordi Alavedra explains how he combined Pulldownit and a fluids solver for breaking several glasses with wine.

I started this project with the aim of testing how Pulldownit behaves along with Cg fluids, and also as a practice in the use of  Pulldownit  plugin which was pretty new to me. I decided to make a 3 glasses shot for being more genuine than the usual “wineglass breaking” . Besides looking at the web I hardly found any good test of Pulldownit and fluids, so I was a little scary about doing it, but I have to say it was much easier than expected.


Shattering with Pulldownit

PDi counts with several patterns to shatter the  models,  fist I did was  testing them,  I started using “local” shatter style, because of the easy of setting the exact impact point, however I discarded it later because the fragments generated looked more like egg-shell  than broken glass, using “radial” style in around  200 fragments each glass and I got a high realistic look,  I found out that  I had only to adjust the pivot of the model to make cracks matching the impact point with the ball so it was perfect. However I needed the neck of the glasses to remain as one single piece so finally I splitted the glass in 2 parts using “Uniform” style before applying radial shattering.

My plot was breaking the glasses with Pdi, then add fluids in a second step, however I was worried about whether the weight of  liquids would affect the way the glasses breaks or not, so I decided to test it by filling the objects with Maya nParticles, and setting the fragments as Maya nBodies and Pdi Fracture Bodies at the same time, it was perfectly possible and I baked a couple of scenes with different Pdi Fracture settings in this way. I had computed the same scenes previously without nParticles and after looking at one and another, although different results, fragments motion was convincing in all of them, however the scenes including nParticles took at least double slower to compute so I decided to get rid of that approach and compute Pdi dynamics without adding particles.

Dynamics with  Pulldownit
So I set I fracture body for each glass and a Pdi body for the ball and make it break the glasses, that was easy and looked good, however I wanted the third glass to lean in addition to break, I had to try different things but finally it was possible using Pdi Advanced Fractures by increasing the hardness for the  area near the neck  of the third glass. I think PDi Advanced Fractures are  difficult to play with at the beginning, but once you understand it, they are very powerful to adjust details in fracture.
The computation time with Pulldownit alone was around 5 min,  pretty fast and I have to say very stable .I baked everything as Maya keys and saved the scene before going to  fluids simulation.

Mixing Pulldownit & fluids

Second step was computing fluids, for that I had to export the original scene with unbroken objects and the final one with fragments and animation to the fluids application, both files were imported without troubles.  I needed the original scene to fill the glasses with liquid, for that I created one emitter per glass, adding gravity I filled the glasses at the level I wanted, letting  the liquid  settle and setting this point at initial state for the fluids.
After that I had simply to replace all solid glasses for the broken ones, simply deleting them and importing the file with fragments and animation keys in its place, computing fluids took about 8 hours in my computer and meshing the liquids around 12 hours.

I imported the fluid meshes back in the Maya animation file,  I removed all Pdi dynamics data to let only Maya keys in the scene and really nothing more, for my pleasure fluids and broken fragments matches perfectly when playing the scene, so it left just rendering everything.

Render the scene

Once I have the simulation  of objects and fluids done, I had to set shaders and  lighting for rendering the scene. I used IBL with HDRI studio lights,  glass material was an easy one but  shading the fluids took me a lot more, I was playing around with dielectric materials and different Mental-Ray materials, but I didn’t like the look,  finally I made my own one, using  a blinn material as basis,  and adding ramps, surface info and so on to get the look I wanted.


I made some testing with different renders engines and finally decided to go with Mental-Ray because I got the best caustics using it, maybe because Im used to
it, I don’t know. It took 3 days to render both views, side and perspective, after that I did some color correction and deep of field adjustment in After Effects.

Conclusions

Im happy with the result I got, I know inst perfect, but quite believable I think,  my first experience with Pulldownit was very good, it is easy to understand and  a powerful plugin, my plot was breaking the glasses but two of them had to stand after collision with the ball  and the last one leaning  and fall,  Pulldownit lets me the ability to do it, that’s dynamics control 
Besides It was amusing to work with this plugin, fast response and stable, very nice.  The integration with fluids was much easier than expected, it would be great to get involved in  a professional project using both tools.

Author: Jordi Alavedra
http://www.linkedin.com/pub/jordi-alavedra/1b/709/659
https://vimeo.com/68601781

Destroy a horse cart by Andres de Mingo

For this shot I had to test new  features of Pulldownit 2.7, specially  transition animation-dynamics capabilities. I needed and animated model  made of diferent pieces and break it upon collision, Pdi wood shatter works very nicely so I decided to try with a cart, besides I had modeled a horse sometime ago so it was perfect for attaching the cart to it.

Animating the horse

The horse animation was made using a quadruped animation by layering techniques for the run-cycle instead the pose to pose or straight through techniques. You can find an amazing tutorial on how to animate a horse loop in this way here:

The hair of the horse was created with the Hair and Fur modifier in 3ds Max. The render mode of the hair was “geometry”, in order to get the depth of field of the Vray Camera rendered fine. The animation was made using the live mode dynamics.

Modeling and animating the cart

To build the cart I used some vintage photos as reference. The model is made of diferent pieces and single planks in order to not having issues when shattering it, the fence was built in the same way. The cart was rigged in two parts; one attached to the horse and another one more “free”, so I can introduce some noise in the animation when the cart is running fast over the irregular terrain. I used a couple of dummy objects attached to the geometry to drive the motion of the car straight toward the fence and secundary motion with the terrain slopes, the front and rear wheels where grouped  separately to make them spin around  its axis. I used some vray dirt in the material diffuse so that we can have a stronger ambient oclussion look. Vray ambient oclussion was checked too.

Shattering the cart

I needed different parts of the cart to break different, I mean, wheels should break different than the deck of the cart for example, so first thing I did was separate the parts of the cart in different layers, chassis, front wheels, rear wheels, seats, and  so on..then I started to shatter geometry per layer, making sure the active layer was the same of  the current shatter operation,  cart deck and footrest were shattered  using wood style the rest of  the cart was shattered using uniform style in a few fragments, 8 or so. Pdi 2.7 kept the animation of  the parts after shattering, that worked perfect.

Setting the cart  in dynamics

I created a fracture body per layer,  in this way I could control the fracture of each part independently, as the cart is animated I set each fracture body as static and activation at frame in order to force them following  the animation until colliding with the fence, I reduced clusterize to 0.0 and set local propagation far all pieces. Finally I used PDI advanced fractures to prevent some parts to break at all, the axis of the wheels, and most part of the deck and one of the rear wheels doenst break because of this.

Breaking the cart in dynamics

Despite the near 800 fragments involved in the simulation and the complexity of having 8 diferent fracture bodies in dynamics, Pulldownit computes the cart destruction very fast.  However at my first tries the cart started  to break  too early, far before reaching the fence; I found out that the issue was caused because the cart was colliding with the terrain when moving and also different parts with each  other,  using new parameter “unbreakable until frame” was the key to solve it, just setting this parameter at a frame near to the fence solved the issue. Both the cart and the fence should get broken so I shattered  the fence as wood splinters and created a new fracture body for  it, however I set the fence as fully unbreakable using the new parameter in v2.7 to concentrate in the cart fracture first, it was as easy as disabling this parameter for making the fence breaking aswell once I was happy with the look of the cart destruction, that is another interesting use of this

For fine tuning of fracture and adjunsting the strenght of impact I tweaked hardness and damping parameters of each  piece interactively, for doing it I hid all layers except the one I was computing, Pulldownit seems to get along very well with layers. When I was happy with  the way each piece was fracturing I simply unhid all layers to bake the final result.

Conclusions

I think I got a believable breaking of the cart, Pulldownit 2.7 behave stable and fast, transition animation-dynamics worked nicely and  new parameter “unbreakable until frame” was a must to get the pieces breaking at the right moment, using layers was key to can handle each piece separately

Author:Andres de Mingo
https://vimeo.com/user5590107

 

 

The Cave of Buddhas by Pedro Ivan de Frias

Pedro ivan de Frias kindly explains us how he did this appealing shot of ice blocks breaking in an ancient cave using Pulldownit plugin for shatter & dynamics. You can see the final shot here:

MODELLING

First I made the cavern, starting from a simple poly-plane with a bit of noise as ground, a thick wall on one side and several leaning pillars on the other. The pillars were sculpted from poly-boxes and adding noise later, there are also some sparsed stones over the ground made in the same way.  On the middle of the thick wall I managed to embed a velociraptor skeleton, I made the model some time ago and I thought it would be nice to include it in the cavern as a fossil, coming from the back of the scene there are several Budhas statues lined-up, I made it sometime ago aswell and I thought placing them on the entry to the cavern would make the set more mystic and bizarre, hope I got it.

In the middle of the scene I put 3 columns of ice, I made just one from extruded splines and smoothing the edges, as this object will be fractured later with PDi, I checked that topology  was correct, I mean, closed surface, normals pointing ouside and so on.. , then I cloned the column and translate it to create the other columns, and rotating it in different directions for simulating the columns are different and saving work. Finally the impact object was made modifying it from a poly box.

Texturing & Lighting:

Creating the materials of the scene wasnt easy, the cavern is cover of ice everywhere, and the columns are made of ice themselves, sadly there isn’t a button in mentalray to create an ice material automatically, so I started to play with fall off of reflectivity and transparency channels until achieving the desired look, adding some channels with custom bitmaps to get an uneven look in the transparency effect , finally adding a bit of glow and selflighting.

For the inner material of the fragments created by PDi, I increased the transparency and used fresnell reflection. For the impact object I set a material which emits green light with fall-off, so in this way it illuminates each ice-block with a green-coloured light right before breaking it, creating a nice light-trough effect I think.

There are quite a lot of lights in the scene. An skylight as ambient an a sunlight and volumetric lights for the entry of the cave outlining all the shadows, I placed also a few area skylights here and there.

SHATTER & DYNAMICS:

I wanted the columns breaking in little fragments in the impact area and generating big blocks of ice farther so PDi local shatter was perfect for it, making sure the “create pdi cut mat” option was set, I broke each column in 2200 shards, that’s a lot but PDi generated the shards in a few seconds and later it computed the dynamics of near 7000 fragments in scene quite well and pretty fast, amazing tool indeed.

I wanted the columns breaking in little fragments in the impact area and generating big blocks of ice farther so PDi local shatter was perfect for it, making sure the “create pdi cut mat” option was set, I broke each column in 2200 shards, that’s a lot but PDi generated the shards in a few seconds and later it computed the dynamics of near 7000 fragments in scene quite well and pretty fast, amazing tool indeed.

After shattering the columns, I set the PDi fracture bodies, by checking the “relative to mass” parameter little fragments break easier than bigger ones by default, just what I needed, in addition I wanted the top and bottom parts of the columns not to move, for getting it I used Pdi advanced fractures to set those parts static.

For the rest of the scene I simply set all objects to Pdi rigid body as “auto”, It worked fine for most objects however a few large stones of the environment have complex shapes and I had to set them as Pdi rigid “mesh” to get correct collisions  with them. The impact object is animated with keys, following a straight line and rotating around so I set it as rigid “mesh animated” so it kept the animation keys when moving and colliding,

Going into dynamics I set friction parameter very low to get the sliding motion of ice, that worked very well but sadly two other issues came up, when the impact object hit the first column the fragments were flaying away unexpectedly, by other side second column started to collapse before the rod even hits it . After researching on it , it seems the fast spinning motion of the rod was causing the increase of energy on the fragments making them fly away too much, reducing the Bounciness of the fragments and increasing linear damping of the fracture bodies I managed to control the blowup pretty well, for the other issue what happened was some fragments of the first column hit on the second one causing it to start breaking in advance, to fix it I simply set the new option “unbreakable until frame” for the columns and they stand up perfectly until being hit. Once those issues were fixed I played with hardness and clusterize parameters to get different looks of fracture and finally set hardness around 150 and high clusterize becouse the fracture looks nicer to me.

Pdi tooks around 3 hours with substep 15 to compute the whole destruction, pretty fast having in account the near 7000 fragments involved. After the computation was done I added jagginess to the fragments, a great, great option in PDi to get a less polygonal look, and it worked like a charm setting a resolution of 1 and low strenght, because ice blocks looks near polygonal I think.

Render & Composition:

I sent 14 diferent passes to render with mental ray using LPM manager for this. Rendering tooks much more than usual because the transparent and reflective shaders of the ice. I wanted a slow motion effect just when the rod hit each column, for getting it I had to change the time rate of the animation to 30*4 and render those passes separately and compose with those of normal speed later. All passes were composed together adjusting color and contrast in local areas,
I stressed light through the entry of the cave by setting a bright background outside and applying a lightwarp of it to the rest of the passes.

Author: Ivan de Frias
http://vimeo.com/pytonproducciones

 

 

Building Collapse by Ivan Khmel

Ivan Khmel has done this appealing shot of building destruction using Pulldownit plugin in Maya, he kindly explains details about production in this article

In creating this effect I wanted to make it as Hyper-real as possible. Looking for a high resolution photo online of a abandoned brick building. The reason I picked a abandoned building over a street image building image is because a street image has cars and people that would have to be taken out or replaced.

Camera Matching

After finding the photos that I wanted to use. There was a need to establish a Field Of View and camera angle. None of this information was available with the photo, so I used an Image Modeller Software to match and establish the camera in the scene and place locators to model around when imported into Maya.

modelling

Modelling

Importing the scene from the Image modelling software, the first things I did was to lock the camera in position, so you could not rotate or change its FOV. This was to be my render camera. After locking the camera in position I imported the original image as the Camera Image Plane. Using the position of the locators I quickly blocked out the shape of the building using Boxes and Primitives.

The after deciding which part of the building I wanted to destroy which was to be the Main Wall, I set out to model the to be destroyed Main Wall with great detail and in a manner that would lend it to shattering using the PDI  latter on. This meant the wall had to have very clean geo. This also included modelling the inside wall and floors of the building.

To finishing the modelling part of the project I modelled in mid level detail, the position and location of the other parts of the building to be used as collision, for the PDI simulation and later the fluids simulation.

Texturing

Texturing this building needed to be done in a way that would match the style of the original photo.  So after laying out the UVs for the Main Wall I created a shader and imported a textures as a projection, using the original camera as the camera to project the image  from.  After the textures is projected on its baked out using Convert to File Texture setting in Maya hypershade.

In Photoshop the baked out texture is painted on top of, only really used to get the correct colour pallet and some detail locations. Overall the baked out textures rapidly looses resolution on the furthest part of the wall, and that needs to be fixed.

Also the back facing side of the wall will not line up to the photo that was projected so the textures needs to be corrected in that respect.

UVing and texturing the inside walls and the floors using standard methods.

PDI Shattering

Having the Main Wall the Inside Walls and Floors modelled and textured, the wall is ready for shattering. Using the PDI Shatter It Button I broke up the Main Wall the Inside Walls and Floors into 64 pieces each. After which I select out and separated the parts of the Main Wall, Inner Walls and Floors that I wish to be static. Combining all the static geo into one object. Now we are left with a very low poly shattered wall to add variation to broken edge I went through and re-shattered each shattered bit on the edge by 10 or sometimes 20 if it was a rather large chunk. After which I would select the shattered chunk that would be touching the Static geo and Merged them with the static geo. This gives the edge more of a interesting detail.

I set the Static Geo, Ground Plane and other building parts as collision Bounding Body/Mesh/ Passive objects in Create PDI Body.
Then set the shattered parts as Body/Mesh. Separating some parts into a different groups to be easily selectable. The objects in this separate group was given a small velocity away from the walls normal direction, to create a weakness which would come out first.

PDI Baking

Now baking the simulation . This stage for me was a stage of trial and error. Looking in what way the shattered geo falls, making sure the speed and self collision between parts is working in a certain way. Also looking at a large amount of reference footage of bulldozers ripping down buildings. PDI allows to bake to keys in a very straight forward fashion. After the PDI parts are baked into keys
its ready for cleaning up the scene by removing PDI nodes leaving you with geo parts with baked in keyframes.

Adding Instance Particles

After the shattered geo was baked into keys it was time to added more debris flying down with the shattered chunks. Giving the illusion of more detail and a more realistic collapse. Considering that all the Main Wall parts, Inner Wall parts, Floor parts where separately grouped during the modelling and shattering process, that made it easier to select a number of parts and attach emitters to them. I had hundreds of emitters but only two particles systems. One particle system for instanced bricks and one for instanced concrete. To make the selection of emitters easier I used Mayas Quick Selection Set Shelf Button, so if say I wanted the Main Wall emitting parts to start emitting all at the same time I used the Quick Select Shelf Button which I set and change the values for all the selected emitters in the Channel Box. I set the particles to collide with all the static geo as was done with PDI simulation. Instead of baking the instanced particles into key frames with would blow the scene out in memory I used a simple “seed(id);” expression which is meant to play the instanced particle simulation the same way each time. I added custom expression for scale and rotation and random selection of particle ID with the brick and concrete objects instanced.

Adding Fluids

At this point what needed to be added was the dust. I want to have full control over how much dust comes out when falling and how much dust comes out on impact with the ground. After a few rounds of experimentation, I decided to go with having a new one particle system emitted from the emitters already created attached to the PDI baked parts. This new particle system will die and create a new second particle system on collision and that new particle will emit its own third particle system. This final third particle system would emit the fluids when the parts start to hit the ground. And the first particle system falling through mid air before the collision will emit dust fluids, simulating dust coming from the crumbling building. Using this set up I was able to make fine adjustments and tweak very minutely how much dust was coming out and when.

Lighting & Rendering
Lighting was basic. All that needed to be done was matching the overcast lighting of the original image plate. I used Vray and a directional light with a Geo dome and a light emitting material on that dome.

All the collision geo was set to Use background(Vray Mtl Wrapper), so in render image would alpha out all the non collapsing wall yet still receive shadows from falling objects.
The fluids are rendered using maya software because it was faster. On the pass of rendering fluids everything other then fluids was set to Use Background shader.

Final Comp

Putting it all together, adding the rendered wall collapse with the fluid render on top. After all this a slight color grade to match to the original plate and a overall addition of noise.

Shot Breakdown

 

About the Author

Hi everyone my name is Ivan Khmel. 3D generalist currently living in New Zealand. Originally my study was in illustration , photography, film making and 3d animation. And for the last 7 years I have been working as a generalist 3d artist in the games industry. As of a year ago I have taken up a personal hobby of learning Realistic Visual Effects and am currently working as VFX artist in a iPhone game development studio, which gets me dealing allot more with 2D animation, sprites particle effects and UV scroll animation.
You can see my website here

www.ivankhmel.com

 

 

Westminster Abbey Cg destruction

At Thinkinetic  we enjoy to destroy ancient buildings digitally :), this time was the turn of Westminster Abbey in the heart of London, destruction was integrally done in Maya using Pulldownit plugin and Maya fluids, in this review the team explain how we made it.

Shatter & Destruction

Our Abbey model was about 57000 faces, not too much really, but it wasn’t a single mesh rather  was made of about 1000 different objects; walls, columns, beams, turrets, windows, hallways, roofs, buttresses,.. everything was made of  independent objects, the first thing I did was checking all objects and close  those which were open to shatter them without artifacts. We wanted a large number of fragments for the  abbey destruction, but keeping it below 5000 shards, because above this  Maya viewport start to work much slower and also PDI dynamics takes longer to compute.

For creating the long crack over the front wall I used path-based style, drawing a spline over the surface and shattering the wall in about 1000 shards, most part of the fragments would belong to the towers though, so we set a count of 1500 shards each one, however the towers were made of many different objects, some of them were large as walls and columns and needed  more fragments while many others as trimmings were very little and needed just a few cuts. I grouped all large objects in one layer to shatter them with about 32 fragments per object  the selecting little ones to shatter them in about 4 fragments each one, after that there were  still some large pieces, I reshattered them taking care of not surpassing the 1500 shards count per tower, I used uniform style for all cuts. Finally I shatter the battlements row on the right side using uniform style with about 500 shards for all of them.

Destruction work was huge in this set so schedulled in three stages, the wall crack, towers destruction and battlements row collapsing. In order to save computation time, wall crack was computed first alone, then baking keys and removing all pdi data to start with a clean scene for the towers destruction, I set everything to convex hull and activate at first hit also create some clusters of fragments using fracture bodies, I placed a volume axis field for each tower near the clocks, animating magnitude to make the towers explode at different frames. In order to save performance I wrapped the abbey with some boxes set as static to make the fragments collide with it in place of using the original geometry, PDI took around 25 min to compute dynamics for near 3000 fragments, quite impressive. After the destruction was done, I bake keys and remove pdi data again before starting with the battlements collapse.  I started shattering the whole row of turrets with uniform style, then creating  a fracture body for all fragments adn using Pdi advanced fractures to make the turrets collapsing sequentially at diferent frames, I tweaked break energy several times until getting the desired look.

Maya Fluids Setup

My goal was to simulate dust and smoke using Maya fluids, and integrate it with the destruction previously done using Pulldownit plugin, first I had to decide from which fragments to emit, also I created some additional objects , making them invisible, to emit from. Once the emitters was set, I made a sketch of the moments when the objects would start to emit, finally I divided the task into 3 phases, the main wall crack, towers exploding and towers collapsing.

I modeled and object following the shape of the wall crack and split it in two to create an emitter at the first frame an another one some frames later, I chose to emit from surface and set keys for buoyancy  and particle rate in the emitter  so It emits for some frames and then progressively disappears. Additionally I combined some of the flying fragments to emit from them as well, in this way I had to create only one emitter for all of them at once.

Finally I set the ground and some parts of the structure as passive so the dust will collidewith them, leaving some parts unassigned so the dust could pass through it.

For the towers explosion I combined some of the flying fragments in a single object to emit from them, I did the same for several clusters of fragments of both towers, I had to set a high resolution for the containers, between 120 and 250 cells, because otherwise the smaller fragments would emit intermittently, I wanted the fluids to look like dust, the main difference between dust and smoke is dust tends to drop while smoke tends to rise, so I tweaked bouyancy and density of the emitter to get dropping wakes of fluids, finally I set keys for emission at different frames for both towers as I wanted them to explode with a delay.

The last stage was the collapse of towers, it was more difficult to be done, fragments didn’t fly away neither were falling smoothly, instead they were dropping a bit then stopping then dropping completely, I had to key the bouyancy, density and turbulence of the fluids so it started lighter and smoothly and when the tower fall completely I increased density and turbulence to speed up its motion and make it look more chaotic.
The original model was too complex for using it for collisions with fluids, so I modeled a proxy-object with the overall shape of the abbey, setting it to passive for making fluids collide;. I created again one container per tower in order to control fluids independently for each one, those containers were of high resolution as they had a long path towards the  ground, and extending quite a lot later over it. To create the feeling of the dust coming through the walls I emitted from inner fragments only.

Maya Fluids Render

Before going into render I cached all fluids to can distribute later the task in several computers. I order to integrate fluids passes with the rest, I created 3 render layers, one with the fluid alone, another with the fluid and fragments in alpha channel, and the last one with the shadow of the fluid projected over the ground. I used Maya software for the render layers and Mental ray for the shadow pass, per frame render time was quite long due to the high resolution of fluids. I used a ramp from white to dark beige for fluid density, and a couple of maps in texture and opacity;  there was only a directional light in scene so to prevent from the fluid looking too dark in hidden areas I added a fake lighting for it using ambient light parameters.

Shading & Texturing

The model counts with 10 different textures made from pictures of the real building,  taking parts of walls and windows pictures first thing I did was making seamless textures from them, after that dirt and wet traces were added for getting the look more realistic and gloomy,

We haven’t real pictures of the roof on a top view, so I decided to apply it a texture made from 4 different bitmaps of rusty and wet metal, I composed all of them in a single image adapted to the geometry of the model.
Although the environment around the abbey is only sketched, we wanted the ground to appear like burned and wasted so I made a noise mask for the ground composing different kind of stones and adding dust and burn filters.
The textures were applied using an unwrap modifier for the ground, roof and main walls, using a 6-sides mapping for the rest of the objects, always having in account the seam with nearby textures, really a surgeon work.

The abbey is featured in a realistic way while the environment is just conceptual, in this way the church clearly stands out from the rest, there are 17 lights in the scene, direct light is projecting a skewed shadow affecting buildings smoothly, ambient light affects everything though, a few lights are placed inside buildings around and behind the abbey to highlight the main model.

Render & Composition

Rendering was distributed  in 32 passes, environment and Abbey in different layers always, we needed another layer with 3 passes for gathering the reflective light of the Thames River behind. Shadows were rendered in two steps with AO and direct channels mixed to give some weight to the scene, there are some mist passes and finally Zdepth were balanced in composition to get more depth of the scene view.

it took 5 days to render 32 passes of 500 frames each one, in a few computers using png format. Postpro was done using color correctors and RGB masks, using 3 reference frames only for tweaking colors and shadows to enhance the abbey destruction, applying the result to all frames after that. Dust passes were composed balancing the alpha channel for cutting down the density and noise levels, making in this way the flying fragments more noticeable however we wanted to still keep the appealling look of dust clouds, for getting this effect I tweaked contrast level until getting the desired look between fragments and dust.

Credits:

Shatter & Destruction
Esteban Cuesta
https://vimeo.com/user1988932

Maya fluids setup & render
Roberto Martin
https://vimeo.com/user5582471

Lighting, Texturing, Shading & Composition
Pedro Ivan de Frias
http://www.pytonproducciones.com/

 

Atomium collapses!

No worries, Atomium building is still there ;),  it is just a great CG  job by our friend Przem Sacharczuck using Pulldownit plugin in Maya. He kindly explain some details about production in this article.

Well, Im not a theoretician about CG effects and instead talking, I want simple doing it!
I promise to write something about this video,  I`ll try to be brief.
This project its my personal challenge, last season I was  almost full time spending for testing wide range of simulations so called VFX. Im a fan of all present visual effects in movies, they are improving very fast in last years. I like to know how effects was made, all workshops and making-off`s are very helpfull specially for a begginer in the field.

Actually im training on Autodesk Maya, it is  an usefull software able to almost anything in 3D,  sadly Maya built-in shatter doesnt work  so Pulldownit plugin is a powerfull add-on to Maya for dynamics effects.  In last year I was looking for good plugins, but not many working as I wanted, some plugins generated very poor, unnatural shards, some others have issues when computing dynamics. I find Pulldownit is the best destruction tool for Maya so far, it is fast and stable and  what is interesting Pdi offers ways to make different ways of breakings, as wood, glass and concrete, it is very flexible for every kind of destruction needed!

About this Atomium project, I prepared it in few ways:
First of all- Im decided to make camera tracking to get more realistic result for scene- environment. I find it getting better result than building all scene from scratch, I needed  also some tools for motion tracking & camera tracking. Softwares which offers that possibilities are Matchmover, Boujou and CameraTracker. For best tracking and to avoid any issues in quality of recording scene, this was taken with Canon EOS mkII in full HD quality.
The rest of the project I made mostly In Autodesk –Matchmover, Maya and After Effects for final compositing and color correction.

Finally this scene tooks  me quite a lot of time to be done, about Pdi,  I had to simulate and check several times for the best way of simulation. About Pdi simulation in Atomium I made 3 levels of shards, meteor, top of Atomium and bottom level. Finally I used advanced Pdi fractures for adjusting breaking resistance in diferent levels.

The rest of effects in Maya also tooks me some time, especially make the cloud blasts. Maya fluids needs lots of Ram and fast graphic card! This scene have two fluid containers which working separately. 1st res. is about 70×3, and for shards very dense about 100x150x70. The flying meteor at the beginning of the clip was made in box~100x150x70 container with 3 different emitters: fire, burn and smoke, It took me some time to adjust emitters for getting  the final look I wanted for the wake of the meteor.

For now im freelancer and enthusiastically looking forward :)
Enjoy!

Tornado by Roberto Martin

Roberto Martin made this impressive destruction shot for his final Maya course project combining Maya particles, fluids and Pulldownit plugin, he tell us some details of production in this article.

Tornado( twister) shot is my final Maya Advanced course project at Trazos School in Spain. My teacher at Trazos warned me that if  I planned  to do a scene very heavy in terms of  “objects dynamics” then using Maya rigid bodies will be surely painful  because Autodesk has taken centuries without fix or update it and it takes kind of forever to calculate.  My teacher proposed me some plugins which I had seen before in internet, I tried them a little, sadly they were not entirely stable and had a thousand and one parameter to edit, besides I was looking for interaction with force fields like wind or newton, however using those plugins was maybe possible to demolish a wall-brick, but definitively not intended for blowing up a mill or a barn using Maya forces. So I searched Internet and then found Pulldownit , the web-site looked nice so I downloaded the demo version and after some testing I must say t was incredible stable, I’ve got good results very fast so I started to use it.

Regarding the twister itself I made it emitting particles from some NURBS cylinders, the particles moved around the cylinders using simple expressions, just displacing their UV position over the surfaces. After I got the motion I wanted for the particles, I made them emit fluid, the result was good but too uniform., so in order to generate chaos I finally used two different fluids, one of them was controlled by the particles and  have no density,  and the second was more chaotic but binded to the other, in this way I´ve got some control in its trajectory. I used a density ramp and self-shadow attribute to mix both fluids in render.

For breaking the buildings my first idea was to use a Volume Axis field affecting PDI objects, but after doing some testing I couldn’t  get the desired result, then I realized I needed more fields for the tornado effect, one for attracting fragments and another one for spreading them out. As I had near 25.000 objects in scene it was very difficult to adjust fields properly for all of them, so I decided to go little by little, I started with the house, leaving everything else as passive. After getting the house destruction done as I wished, I followed with the mill and then the barn. Finally there were two Volume axis fields for the house destruction and one Vortex and one Newton for the rest.

I made by hand the animation of the truck, because I wanted it to roll and go straight towards the viewer, I animated it independently in a different scene, in this way I avoided all the overhead of the rest of the scene, which was too heavy, then importing the keys into the tornado scene.
I used PDI advanced fractures to set some parts of the fracture bodies more solid and difficult to separate and other much weaker, specially the slates. I set the floor as passive so it doesn’t move, several large thin planks gave me some issues in dynamics, they were crossing the floor or got “hooked” on it, so I had to fix a few keys by hand or simply removing those planks from the scene, the rest went smoothly,  behaves quite real and was completely stable in such a heavy scene.

 

Roberto Martin is already working in the CG insdustry, looking forward new videos from you Roberto whenever you have time!

 

LMU Belltower destruction by John Bashyam

John Bashyam and friends made this stunning shot combining Pulldownit plugin in Maya and After Effects, he kindly share some details about production below.

I thought it would be fun to create a video of a meteor hitting the clock
tower at my school. So I went out and took some reference photos, and then
began to model the tower in Maya. Once I was finished, I added some basic
textures and then went out to shoot the actual video. After this, I
positioned the virtual camera in the same place as the camera in real life
in order to get the perspective right.

Now came time for the destruction. I was thinking about using the Rayfire
tool for 3ds MAX, but I figured it would be such a hassle to import my
geometry, run it through Rayfire, bake it, and export it back out to Maya.
That is when I came upon PullDownIt, which would do all of this inside of
Maya. I decided to give it a try, and it worked like a charm.

I selected all of the geometry to be destroyed, and fractured them using
the PDI basic fractures tool (I even further fractured a few pieces so that
I would have some tiny shards). I put a ball in the scene which I was going
to replace with a meteor later through compositing and then ran the
simulation, baked it, and rendered out a .png image sequence.

Next, I went into After Effects, imported my image sequence, put it on top
of my original footage, added some more debris, smoke, the meteor, lens
flare, color correction, and all of that good stuff. Note that it only
switches over to the CG tower upon meteor impact.

Since I enjoy using Maya over any other 3d program, it is so great to have
a destruction tool that opens right inside. PullDownIt does a nice job, but
it would be cool to have some dynamic destruction features (fracture on
impact).

I am currently studying Animation at Loyola Marymount University in Los
Angeles, CA.

 

www.savageanimation.com