Niall Horn VFX's Blog- Making Of My Work & RnD

Monday, 27 April 2015

Underwater Naval Base Destruction FX Work

All Images © Niall Horn

So this is a look at the FX work/RnD I did for what was supposed to be a 10 shot sequence with me as the lead FX TD! However the project got scrapped 3 days before my turnover due to budget problems on there end. As Stressful as this was I already am on a new gig and have all this fun FX RnD to show. I worked on the FX Setups/RnD from Mid March to 21st April. I also did all the Lighting/Rendering/Comping You See. The Idea for the project is an Underwater Naval Base That has epic destruction in 10 shots. I was brought on very early after the previs stage, and stayed on until the cancellation of the sequence. I've worked with someone who was in a similar situation as this, and he was not allowed to show any of his RnD, so still happy I can show my work on my reel!

Making Of-

My First part of production was reference, I knew I'd be alone doing all the FX (And Finishing) due to the budget and I wanted to try and bring a high budget/feature look in the FX to these shots. This was not a generalist project, I had to get high end FX setups and RnD done in a very short amount of time. Reference Wise I was looking mainly at MPC's work in GI-Joe Rise Of Cobra with the epic Naval Base Destruction. MPC Did lots of work with Flowline (Scanlines Fluid Sim Tool) to simulate Underwater Pressue in an Explosion, aswell as Destruction. Other good refernces were Scanlines Iron Man 3 underwater Shots (And there breakdown) and Pixomondo's work on Journey 2 (Underwater Submarine Escape Sequence). I studied these shots frame by frame I wrote nearly 10,000 Notes aswell as looking at US Navy underwater Explosion Studies. In the end it comes down to how much time did I have (Not much) to make the FX looks Physically Accurate vs Cinematically Epic. And that is what I love about FX !

The Naval Base Asset was based on a central building with 6 "Arm" Buildings most of the RBD FX RnD was based on these guy''s destructions! The Asset was sent un-named and in 10'000s of objects so I spent nearly a week just prepping the asset for destruction even having to re-UV some of the parts. Aswell as correct touching vertices. I hate Modelling/Model prep and usally dont have to do it, but in this case I did. 

Doing underwater destruction is hard, not only are underwater physics very different but everything that has velocity underwater creates bubbles, meaning the creation of Various Bubble systems/Tools was needed, aswell a highres Hero Bubble Fluid Sims. The Main System was one made for the static geometry (IE non RBD Sim'd) This was using PFlow to create random debris instances the fall and some rise using random values through Split Amount operators. These Debris they get checked for speed/vel and when they pass a defined threshold they spawn bubbles, as the debris sinks they bubbles rise and delete out of frame. There is also random "Dumb" Bubbles that fill up the scene. More on the Hero bubble sims later. Becuse I was using VRAY I worked on a fully Alembic Proxy Pipeline for rendering all the Bubbles,Instances and Meshed Bubble Clouds. I ended up with some hefty 10's Millions Poly Bubble Clouds per FX Asset however these were rendered as proxies in just minutes thanks to VRay 3. I also did some RealFlow Gas Globes RnD, however these were not used sadly as we went for a more firbeall look rather than shockwave explosion.

Mix Of Bubble Methods, From Instances to Fluid Sims.

RealFlow SPH and Hybrido Gas Globes RnD- Faking Velocity (SPH Has Pressure Settings!)

RBD- As stated above the main RBD work was on Blowing up 6 Command/"Arm" Buildings, There was no room for faking these, I wanted full destruction. Not only are these supposed to be huge, but there also made from steel, breaking/tearing metal is hard to look right. For the pre fragging it was a lot of Manual Work, IE Manually chopping/cutting the geo, There was an Inital pre frag stage to define invidual objects, these were then split into Hero Objects and Non Hero Objects. Some of the fracturing was done using a custom Voronoi  method to get rid of that Voronoi look. I also modelled basic internal destruction elements like bent wires and pipes.

Command Building C's Pre Frag Stage (In Sections)

My Tool For Destruction Was Thinking Particles (TP) right now there is no other tool that can handle geometry with not so great mesh in large quantities so well, while maintaing accurate collision detection aswell as iterative speed. The Shape Collision Solver although old now is still  one of  my favourite solvers for RBDs out there and I think i'll be using it for a while! Also with TP I could work procedurally when needed aswell as setup custom constrain systems via procedural joints. I made a two pretty big TP Setups where using a Bomb Force that defines its radius with a raster of particles I could position it anywhere in the scene and have it affect the fragments. From this joints were created and broken depending on the force, plus lots of friction. The Gas Tanks Destruction were also Sim'd in TP I did plan to do these via mParticles however TP was better. All the TP sims were exported through TP (No Budget For XMesh) and from there I manually added deformation to the hero parts and more debris were added as instances through PFlow. 

Gas Tanks Destruction Sims
                                                                       TP Base Sim (Using Lowres Parts)^

The RBD Side was a lot of work and a lot of fun. The Helicarrier Destruction In Cap America 2 served as good reference for how metal hulls break, aswell as my favourite ever film Battleship! The Systems/Workflows I made here will be used in my Epic Summer Personal Project I keep going on about!

 Command Building D RBDs (WIP)
Shot FX Layout with RBD Sims (WIP)
Command Building B Destruction + Debris WIP

The Non Hero Destructions were keyframed using modifiers to fake the deformation as they fall. The Main RBD Sims were then used in my Bubbles Systems to Spawn bubbles. The two hero command buildings use there own Fume Sims that uses smoke with temperature thats then advected, meshed using Frost to create bubble clouds.

Fume+Frost+PFlow- Bubble Emission Sims (Command Building A)

TP and PFlow Working together! TP Main RBD Sim, PFlow Debris and Fume/Bubble Emission.

Underwater Explosions-

This is where the main FX Assets were created. Using FumeFX and PFlow as the main tools here. I needed a good way to fake pressure aswell as keep the explosions looking epic. The pressure was faked by using keyframed values and forces to get the explosions to Expand/Explode then Implode as they would underwater this implosion pressure lasts barely 3 frames which then is turned off quickly causing the nice looking underwater swirling look, and then neg gravity so they rise up. This meant that i setup around 12 different explosion grids using this method to populate the shots. I didn't have the luxury of a pressure solver/mixing liquid and gas sims to get proper underwater explosions. However due to the time and buget the focus was on cinematiclly epic rather than physically accurate.

A Selection Of the Best sims!

The Next stage is all underwater explosions create Bubble Clouds which refract the smoke. These explosions I went with were more fireball like than gas cloud/shockwave. All the explosions were made as FX Assets theres, the hero sims all were meshed using FumeFollow/Smoke and Frost to there own alembic caches, so an Artist could add these (Or me in the end!) to any scene. The what were to be background explosions/ population grids, these were not frost meshed, they each had there own PF System using FumeFollow and instancing bubble geometries.To make things easier I setup a system where I could open one of the scenes sim it and merge it into my main FX Scenes very quickly, and then quickly load the alembic proxie bubbles in.

Most of the explosions were simple srcs driven by velocity IE No particle voxel emission, becuase for one it makes nicer emissions for this case, also I can let the velocity particles live longer and actually drive the motion of the src's emission. You get much nicer bursting explosions than with particle emission. However it takes longer to setup, and is not very controllable and you cant have velocity particles driving the sims all the time as it'd be impossible to calcluate how the velocity is been advected aswell as how much does Fume influence this into the sims. So in some cases I might use a mix of Particle emission and fire some velocity particles into the grids to mix up the emission a bit. Some of the sims have smoke trails (This would be not realistic underwater, as smoke trails are burning debris in most cases which the water would either extinguish or slow down due the the pressure, however smoke/firey trails look awesome) and these were emitted via particles.

Command Building B Main Explosion Sim (4 Emitters)


Due to the sad cancellation of the sequence, I knew i'd be making an FX Reel of all my work and wanted to render a shot with some of my favourite FX Setups/Assets in. I like to do finishing on shots You kinda have to know how to finish into nice shots when your from a smaller studio background which is good because I can do FX projects and do the Light,RenderComp myself I know my skills are a heavy WIP, but with the ability to showcase my FX in a shot I think really helped show the work I put into this project. Would of been nice to have a lighting department here, but I am looking around and theres only me sat here!! I knew I was started a new project next week so did not have time for enviro fog and proper caustics and proper underwater lighting, so I did most of it in comp just showcase the FX in a finished shot. With VRay is really quick to be able to put Materials/simple shader setups on for iterative dailies, gives more of a clear example of how the FX Sims/Renders will be used and will look.

Lighting/Rendering of the "FX Showcase Shot" !

Overall I really enjoyed the work I did for this project, has defiantly been my biggest yet, sad that the sequence got cancelled but that was out of my hands. I learnt a lot on this project and have some great FX Setups for future use. I really enjoyed the underwater FX Side! Right now I am on a new project smaller scale, but have some more RealFlow 2015 RnD in the works aswell as prepping for my summer VFX Personal Project in my free time which will be lots of FX with full shot finsihing I am amining to do a really super ambitious (And Probably stupid) personal FX project! I am also working on a StarWars Game doing an FX Shot! (Dont worry its not confidential!)

So Just big thanks for reading, supporting my work. 2015s brought some awesome projects so far, I hope to get more awesome projects soon! Thanks- Niall

Underwater Naval Base Destruction FX Reel

Saturday, 18 April 2015

Zombie Head Destruction - FX RnD Fun Project

Hi Guys!

This was a fun little FX RnD done over 4 Nights after work. Last week I was re-watching 300 Rise Of An Empire  and seeing the awesome blood sims done by Scanline and MPC, aswell as the awesome blood fluid sims in TheWalkingDead I came up with this FX RnD.

The first stage was the actual head destruction, This was done by getting a head asset from Turbo squid, I used mParticles/Box#2 in 3DS Max for the destruction, I created a proxy  of the head and brain using RayFire Voxels, these were then sim'd using mParticles to break apart on collsion from the saw. They were glue'd using mPGlue. with Distance Binding and breakable by max force. The Brain was also sim'd using this setup, the brain model was just a Deformed Sphere using a cellular displacement map to create the bumps/veins on it. With the sims I did look into using some drag, but I really wanted to keep the tearing feel you get with mParticles.

Voxelised Head and Brain mParticles Sim
Using glue, plus extra deflectors, to joint the glue to.

I then used a 3rd PFlow System to throwout extra brain debris which you will see in the final RnD, these were just PFlow instances of spheres with noise that bounced off the ground/wall.
The mParticles Brain and Head sims were cached using the Cache Data Operator, and then re skinned to there original high res (Non voxelised) assets. Particle skinner would usally crash my Max around 5-20 times a night! I could have added more detail/debris to the head destruction like eye balls and teeth etc! Maybe next time!

Glue Bindings test with Skinned Particles
Final Skinned Brain and Head.

The Original plan was to cache with Alembic and Export the Voxels to RealFlow and use them as the proxy collsions in there, however the latest build of Crate I am using right now is really buggy, so I ended up using now interaction, but just exporting the head's start pos as reference, to Realflow.. To make sure the blood was behaving the same speed/directions as the skinned head, I got playblasts from RealFlow and max, and compared them on every major sim.

The Setup in RealFlow was using the Standard SPH Emitters, theres two blood emitters, one with lower viscosity/density to create the nice blood burst, and a second with higher density and viscosity to create the more heavy blood, like you see the tendril of blood hit the ground. I setup some Noise Fields to actually drive the blood sims through there velocity rather than just be forces. Noise + Gravity and Direction Gravity was they key to getting the blood tendrilling nicely, like the blood in 300. There was stickyness on the back wall/ground aswell as KSpeed that would slow all the particles down if they were in an area near the back wall/ground with some falloff. I didnt use any attractors, just each emitter had its own gravity (Y Gravity) aswell as having directional gravity to drive the velocity, there were two noise fields for the emitters mainly to get the blast/stringy look from the blood on emission.

RealFlow And Head Destruction Sims- Previews 

The meshing was done with Particle Legacy meshing and some relaxation filter to get rid of the metaball look and get more realistic tendrilly/web like mesh.

The Rendering was done in V-Ray with V-Ray 3's Progressive renderer which is awesome, I like to render my FX Tests rather than just showing play blasts. The blood shader was quite good fun, blood needs to be really dark and a bit desaturated, if you look at some of the 300 work, especially the scanline shots you see the blood is nearly black. The Head was using VRay's Fast SSS2 Skin shader and the brain was using a basic shader with displacement on for more surface details which you dont see in the end as its covered in blood! The Brain debris used this same shader. As this was just FX RnD, everything was rendered in one beauty pass. With some basic AE Comping.

V-Ray Render WIP


Thanks For Looking, 

I am finishing an epic shot for a project right now and will have some breakdowns/RnD to show for it. I am also working on a Star Wars Game doing an FX Heavy Cinematic shot, which is not only FX also doing the finishing, however the focous is on the epic FX Sims (Standby for more info soon) aswell as more RnD Planned, in Both Bifrost Maya 2016, and RealFlow 2015, a second large scale splash shot I will be doing to promote the 2015 Release. And that personal project I keep pushing back !! Gonan be an epic few months!

Wednesday, 8 April 2015

RealFlow 2015 Alpha Demo- VDB Meshing- Pyramid Water Gush

With RealFlow 2015's release on the Horizon and more and more exciting features been added to it, I wanted to make a new demo video of RealFlow 2015's VDB Meshing.

*NOTE Any screenshots of RealFlow 2015s UI are from the current Alpha Build and subject to change. Also I wont be showing too much here, so stay tuned for Next Limit at FMX 2015 For more info on new features in RealFlow 2015 !

The Demo Shot- 

I decided a Pyramid Gushing water looked quite cool! So I used this as a small scale production style test shot, of a large scale fluid sim to test the VDB Meshing. I thought it'd be nicer rather than just showing clay rendered mesh! On the other had, in production a lot of the fluid mesh here would be culled out due to the velocity of the fluid it would be a lot more spray rather than mesh, however I ignored this fact due to showing the mesh is the purpose of this shot.

Note this was sim'd on my second machine (specs below), over easter due to taking a few days off (Not had a proper day off for a long time!Ha!) and due to my main machine working on more awesome shots for The Sea Serpent's Song, Stay tuned for those, I also plan to make a breakdown reel when I am done on that project!

The Sim itself is pretty simple, Using RealFlows Hybrido Solver (FLIP) using two emitters inside the pipes, that have animated speed to have an initial burst of fluid which then turns into a stream of fluid. The particles Die on collision with the ground. I used Noise Fields and Vorticity Boost in the domain itself to get more Air/Turbulence in the fluid rather than a perfect stream of fluid. No Viscosity was used.

Core Fluid (Hybrido FLIP) Sim- Peak 7M Particles

I decided to do secondary sims, RealFlow 2015 includes a Bubbles only emitter so rather than doing Bubbles and Foam in one emitter for this test I did them as Separate Emitters. The Bubbles sim was HY-SPH and the Foam was dumb particles. The bubbles sim will come into play at render time a lot.

Rather than doing Colour By Velocity/Vorticity becuase I am meshing in RealFlow to Alembic and have not found a method to render a grey scale velocity map for comping (Like the method with Krakatoa and Frost, with VRays ExtraTex Vertex Colour render pass). I rendered the Bubbles with fluid mesh, and thus the bubbles are refracted through the fluid to get the White/Translucent Water Colour By Velocity look. This is actually what Colour By Velocity Mimics in the real world anyway, Bubbles refracting through fluid when fluid is move at high vort/velocity!

Bubbles to Refract Through Fluid Mesh

I used Dumb Particles for the foam sim just so I could have more of them and because the foam doesnt need to be as stringy as it would if its surface foam, its gonna break apart into droplets pretty quickly in this sim so thats why I went for Dumb Foam over doing an SPH or FLIP sim.

All sims and Info, VDB Meshing At the Bottom

The Meshing is very simple, Rather than using standard Hybrido meshing I added the new VDB Meshing node into my scene. VDB Meshing breif history- developed by Dreamworks in 2010/2011 VDB (OpenVDB) is way of using/storying Sparse Volumetric Data. Meshing is just one of its uses. Sony Picture Imageworks developed there own similar type called Field3D (.F3D) however VDB has taking over, theres lots of FX support for VDB all around now!

The RealFlow VDB Mehser does not only include the speed and versatility of VDB Meshing but also includes filters such as Erode, and Boolean operations. More info on LuisMs Blog Check it out It also features the "Splash Thinning Filter" as in the standard Hybrido Mesher, which is great for refining the mesh. So the final meshing was done in a few hours, I left it overnight and woke up to check on it, and it was done already :) Really Loving the VDB Meshing, the amount of detail and speed it can mesh from particles for high res sims is amazing, I cant wait to use it in production.

VDB Mehser "View As Points" Feature

Meshing Detail, Meshed this frame within a minute

Both the Mesh and the Secondary Sim particles were cached out as Alembic sequences and stitched together so they could be rendered through V-Ray Alembic Proxies. The Advantage of caching them out in a seq as frames rather than as one file means if something goes wrong like a system crash, you wont loose the whole cache, only the frame the sim/system crashed on. If you were to cache/wrire to one alembic file and had a system crash or powercut then you've just wasted hours of sim time, down the drain... Literately :)

 RealFlow Stitcher Tool  For Alembic Sequences
VDB Mesh Vray Proxy back in Max. (Viewport Preview)

The Pyramid/pipes was a very simple model a 5 minute job, all the detail/stone comes from V-Ray Displacement Modifier using a Standard Max Tiles Procedural Map,  UV Map'd onto the Pyramid, The additional stone detail comes from Fractal Noise Bump maps ontop of the Displacement.   The Lighting was done with Two V-Ray lights and a HDRI Map, as you can see in the final. The water shader I wanted was muddy water pretty simple setup using a standard VRayMtl with Fog to colour the refractions/water.

Muddy Water Shader WIP

The trees were added in to add more completion to the shot, aswell as hide the mesh kill on collison with the ground, they are basic trees (From Maya Paint Effects Actually) using PFlow to scatter them, and then baked into an Alembic file using Exocortex Crate and rendered through VRay Alembic Proxy also. 

Compositing was very simple in AE as all passes apart from the foam were beauty passes, I also rendered the mesh on its own as a claymesh pass.

Final Comp Of The Test Shot^

Big Thanks to Next Limit, Especially Gus,Luis and Dan aswell as the awesome RealFlow Developers lead by Angel Tena! 

Final Demo Video - RealFlow 2015 VDB Meshing- Pryamid Water Gush

Thanks For Looking, Be Sure to check back for more of my work, and Checkout RealFlow 2015 at FMX :) - Niall

Wednesday, 18 March 2015

Meteor Vs Building FX Shot

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

For the Impact Explosions and Firey Smoke Shooters/Trails I took advantage of something i've been working on since late last year. My own FX Asset Libary, becuase a lot of the work I do doesn't need every explosion, every smoke plume every watersplash etc, to be hero sim'd in the scene file (Although many do!). So Every Fume setup I do I save in there, so If I need to drag in an explosion or smoke trails I can just sim them, and merge them rather than having to setup Fume sims/particle emission for every sim in the scene. Both the Impact Explosions and firey shooters were made for this project, however I can re use them, readjust and re sim them in the future now. The Explosions are basic blasts using particle emission, quick burn rate, animated timescale etc. The Firey trails are PFlow particles that spawn trails and are deleted after a few frames to get the nice firey tips (Like you see in many Michael "Bayhem" Explosions both Real and CG!). So these were sim'd in there own file, I then merged each of the two trails grids and the explosions, Positioned them in the scene and set which frame they start. Of-course theres no interaction, which is not needed, if it was this approach would not work.

 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!


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.

Thanks For Looking! I've Got More Projects Coming Soon! -Niall