All Images © Niall Horn VFX
Hi Guys,
I posted a Work In Progress of the shot last month, Its been a super fun perosnal project to work on, in the past 2 months on and off (Mainly after work). This project got pushed into my Inactive folder through January, As I properly started the project in February again I got an amazing offer from a big VFX Studio, sadly I cant take it due to other concerns but it made me want to go back and turn this RnD into a finished shot, I am trying to do this a lot., I love doing FX RnD in my spare time, but I have been trying to find a niche for myself where I aim to put my RnD into a Production Shot, which is where my generalist skills come in handy for Lighting/Rendering/Comping. Plus I got loads of RnD and FX Notes out of this shot!Shot Production-
Making Of Meteor Vs Building (Destruction of the NHVFX Office's!!)-The First WIP is on the end of my 2014 Reel, as I say the idea came to me because i've been doing lots of fluids recently and wanted to do some Destruction RnD, also I knew I was going to be using thinkingParticles (TP) in production this year and hand't used it for a while. The Amazing thing with TP is the actual main setup for the Shot layout and early RBD Setup was done in one night!
Reference for this project was looking at Scanlines shot in Battleship with the Bank of China Destruction (One of my personal favourite shots/sequences,) I watched this frame by frame many times, theres so much little details put in there when you watch it frame by frame you don't notice in realtime. Also my hobby of watching lots of building demolition videos on YouTube. The Real life ref was used for the RBD/TP Sim Reference, wheras these did not serve aswell for the FumeFX Sims Reference.
The Modelling of the building is pretty simple, not based on any real building in paticular, the thing I added more time into was the interior details of the buildings break section which get torn apart and hidden by the dust! I modelled some tiny computer monitors in there, also office chairs, a few bookcases and desks are also in there! I even added a banner which flies out around frame 75 which says "Offices For Rent" for a bit of a laugh :) , but again its covered by the dust and explosions so you cant see it very well! (I'll talk more below about this, I added lots of Papaer and Extra Glass and Concrete Debris).
Office Objects^^
Now try and find them with all the Debris ontop!
The TP System is using SC (ShapeCollison), I spent a bit of time experimenting with Pre fraging vs VolumeBreaker (VB), in the end I used VB to Procedurally Fracture the Concrete and Glass. All the Objects and extra debris were pre fragged. The Activation from the Meteor collision was in the end using an Omni Light which activates the First level of breaking, a frame before the metor collides with the building. Looking back I should/could of done this via Distance Threshold of the Building to the Metor, which is a more procedural approach. However the Omni light only activates a path of destruction led by the Meteor which then spreads to the whole buidling break section (By testing the velocity of the fragments in the first group (Break Level 1) and then if the exceed the threshold they go to a new group which breaks them again (Secondary Fragmentation).
Omni- Parented to Metor Activates Level 1 VB Fragmentation
Once Level 1 Fragments Exceed Vel Threshold, They Get Secondary Fragged
The Final sims were ran in a day why I adjusted settings, one thing with SC with is kins of a blessing and a curse is the high amount of friction you get. This is great when needing cheap bending/clustering of fragments (although ideally you'd use a Joint Setup). So I turned the Friction right down as Concrete and Glass needs mass to show the scale. The Glass VolumeBreakers Fragmentation is using a more Radial Voronoi pattern whereas the Concrete VolumeBreaker is using a more standard Voronoi Pattern. The Level 2 break has less gravity on them, as they are smaller and thus lighter. Same for the office objects they have less gravity. The bigger fragments have more spin on them however as the samller frags dont have spin which is deliberate, because I initially planned to emit dust from these and spinning frags would mean needing high substep sims. Once the sims were tweaked I used XMesh (I luckily got on a previous project an am loving it for caching!). I cached each group out to separate caches as changing topology in one cache is a nightmare to work with, especially when doing Fume and extra debri sims ontop. This means more HDD Space, but worth it.
The Final TP Destruction Sim/s
Becuase I find it easier and a more smooth workflow, I decided to add all the Paper, Extra Concrete and Glass Debries in using PFlow. Using PFlow particles been born on Xmesh Caches can be a bit slow however, due to the geometry not actually been in the scene and is reading in from a cache. I mainly used Lock and Bond to lock particles onto the cache and then speed test them so if they exceed a speed (Just like in the main TP Setup) they emit Concrete debris, and paper etc.I then matched gravity in PFlow which was easy, and used Spawn and Age test to birth more debris needed in the slower areas and also delete them have a set amount of time so they debris will stop emitting on the frags and then fall to the ground. These PFlow Systems were then themselves Xmeshed and I setup a Final RBD Scene with all the caches together and checked they were working. I did delete some and key-frame some fragments/debris that fell to quickly or exploded, but this was easy. I added a sign ontop of the building a basic asset saying NHVFX (NiallHornVFX) for fun, I keyframed this reacting to the impact.
PFlow Debris Playblast Running
Viewport Preview of the Final Destruction Sims
I decided to render a WIP/Clay Render with V-Ray of the Building Destruction out, because I knew I was not going to be able to work on it for a while again due to getting a job on The Sea Serpents Song Project. Note I changed the camera, this was the original camera, but I changed it to a low angle shot to give more scale.
I resumed production on the shots, on my nights off late Feburary and worked on the shot, most mights for a few hours (Including sim and test render time). So next was onto the FumeFX Sims.
I wanted to go all out on the Fume Sims, I first started on the Meteor Fire/SmokeTrail sim. I've done long burning object smoke trails on 3 projects now, from Warthunder's B17 Engine Explosion. As any FX Artist/TD knows doing Fluid sims that need to trail over a long distance is a pain! Luckily the camera is quite tight so the grid didn't have to be a long as it could of been. I first went to Fumes N-Sim, However becuase I was using 3 grids, the sim time and turnaround time for iterations even at Lowres for testing sims was too high, so I decided to stick with one grid, and switch this project over to my more powerful machine, therefore I could only work on this project a few hours a day once I'd finished work, I used ObjSrc Emission from the Metor, I wanted dual coloured smoke mixing on the trail so my plan was to use to noise maps on each side of the metor and use these as emission maps in the Obj Src, this kinda worked, but I ended up needing really dense smoke emitting otherwise it was really think, so I ended up using no maps, just diffrent sides of the metor to emit Dark Grey/Black smoke and also a Lighter coloured grey smoke on the other side.I actually didnt use Fire Creates smoke as I wanted control over the amount more easily, so I used Fuel,Temp,Col and Smoke emission all in the Obj Sources (Using Colour Caching in the Fume Grid). I also used Wind to push the smoke backwards a bit and to have it expand more, I did NOT want the typical Straight Meteor Smoke trail!On the other end of the spectrum I didn't want it to be too turbulent and thin fire and smoke. I used an Effector to control the turbulence based on the fire strength.
Fume- Meteor Grid WIP
Meteor- Mid Res Test Renders
The Dust was actually emitted from particles birthed on the secondary fragments XMesh Cache (No SpeedTest) I just had particles born on them for a few frames when the Meteor hits and then keyframe the smoke (Dust) emission to die down. I also used a low velocity multiplier so when the dust particles died they did not leave big mushrooms, to hide the low velocity I used wind and high gravity in the dust sims to push it following the fragments. I managed to get away with using no collisions between the Fume Voxels and Fragments/Debris at all for the Dust Sims. There was a little bit of stair stepping present in the dust sim due to the Xmesh Frags having such a high velocity from the Meteor Collision, this was hidden anyway with MotionBlur.
HighRes-Dust Sim Front
All the Grids- Voxel Preview's
Impact and Exit Explosion and Trails- RAM Player Test Render
I didn't use much mutliscattering here as for One the shots in daylight, so there would be not as much scatter from the fire to the smoke, Two the camera would be exposed properly so there wouldn't be much visbile light coming through the smoke anyway, and Three its not the look I was going for! The Impact Explosions and Trails were rendered togheter, then the Meteor Grid by itself, then the Dust by itself, for more control in comp. Each of these rendered, Beauty,Fire,Smoke,Velocity and Z-Depth passes for later use in Comp.
The Building,Meteor and Debris were rendered in V-Ray in a Single Pass, (Beauty,Vel,Z-Depth,Refraction). I rendered a Refraction pass so in comp I could use it to pull a luma matte on the glass and convert to an alpha matte which would be use to fake the sky reflection on the windows for more realistic reflections, then off the HDRI only. I also used a few other V-Ray lights on the building, I dont think I ever light only using a HDRI! The XMeshed Caches carried the UV's from TP so I added Procedural concrete textures of fractal noise and bump fractal noise aswell. Also the Glint on the Glass is done in comp with an animated lens flare, I felt that was a good idea and helped sell the shot as been more real, its a subtle thing not many people notice which is exactly what its meant to do!
Building Beauty Render- With Motion Blur and Z-Depth DOF
Basic AE, Creating Luma/Alpha Matte for Glass Through Refraction Pass
All the Fume Passes were rendred with Holdouts/Mattes for all of the debris, becuase the XMesh's are cached they wont change position so aslong as you match the motion blur on all passes you cant see the mattes of each fragment. (They are nearly 10,000 frags, all with mattes). The Skydome was rendered and the background buildings are 3D Layers using a 3D Camera matching the camera in Max. There was a small amount of ColCorrection done on the building but not much.
Building Comp WIP
The FumeFX renders were comp'd smoke first, then fire. I wanted to make sure the fire stayed saturated, on previous projects I've ended up taking a lot of the saturation and contrast from the fire, to help blend it to the show, but this is a bad habit as fire needs to be saturated in a shot like this with sunny environment/lighting. The fume sims were lit using Spot Lights to match the HDRI however I deliberately added a bounce light/second sun at behind the grids so theres nice light shining through the smoke. I also rendred a GI pass of all the Fume sims fire casting onto the building and used this in comp. I did some minor masking to get softer edges on some parts of the smoke, but due to fire and smoke been sperate not much of this was needed. I added a small grade and sharpened the final renders deliberately.
Fume Passes Comp'n WIP
Once I finished the shot after quite a few iterations, mainly from tweaking the fume passes I made a few breakdowns, I love breakdowns, mainly watching them, creating them can be more time consuming than the actual shot, as alot of people know! But its worth it to show the work you put in.
More Comp WIP!
Overall I spent 2 Months ish on and off working on this shot, Its been good fun! I plan to step up my personal projects to more epic ambitious FX Shots this year!
FINAL SHOT AND BREAKDOWNS
One another note, Please dont reupload screenshots or the final shot without permission (PM Me , i'll respond ASAP) and ofcourse do not duplicate. I had work stolen earlier this year and then used as promotional material, I caught all persons involved and named and shamed. Stealing work is pretty sad and Its a frustrating experience in our industry.
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