Phone Camera and PhotoScan

I was interested to see how good the results would be to use my phone camera (Sony Z1) for Photogrammetry (with PhotoScan).

It turns out the results were pretty good! The final meshes are rough, and the textures are pixelated, but the results are usable in production.

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Flip Fluids: Mud and Water

This is a test to see how 2 liquids of different densities would interact. Each fluid also has separate viscosity settings.

To get this working I created a volume in sops, scattered points inside the volume, and then gave them custom point attributes to describe density, and viscosity. The water and mud were each assigned point groups, and then it was possible to separate them and assign the correct point attributes.

The mud has a varying viscosity from 100 to 1000,000 which creates the clumps within the mud. This is set in an attribute VOP in sops, and is driven by a random noise.

In dops the particles are fed into a Flip Object node, and the initial data input type is set to Particle Field to pick up the points created in sops. I also matched the particle separation value in the Flip Object node to the Points from Volume node used to created the points.

The liquids were meshed in Houdini and exported to Max using alembic.

The scene was rendered with Vray using a single dome light set to image based lighting with an HDR used for lighting and reflections.

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Houdini Flip Fluid Viscosity by age

Quick test to change the viscosity of a flip fluid by particle age.

A point attribute called birthframe is made in Sops so that each particle knows when it was born. Then in Dops a Popvop is used to read the birthframe attribute, and subtract it from the current frame of the sim which gives the particle’s age. This age is then passed to a fit range node which fits the value of 0 to 40, to 0 to 5000. This is the value written to the viscosity attribute on each frame.


This is what the flip section of dops looks like. The popvop is placed after the source volume for the flip fluid.


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Houdini Flip Fluids in Max test

Krakatoa Particles playback in Max viewport

This is a first test of getting a Houdini Flip Fluids sim into Max for rendering in V-Ray.

I used the Krakatoa PRT Rop driver available from this site:

Which is pretty awesome. Drivers are available for Houdini 13 and 14. The version I tested was for 14.0335. The driver is easy to install, and is then available under a custom section of the Output drivers.

As well as baking out the particles to PRT files, the Rop driver can also write out the particle velocities, which are read by Frost back in Max. V-Ray is able to use the velocity data for in-camera montionblur.

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Thinking Particles Breakable Joint Tests

A series of tests varying the breakable velocity value for joints. The strength of the joints is also effected by a distance test to the center of the force that’s used to exploded the boxes. In some of the tests I add a random multiplier to add some variation to the effect.

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Nightclub Visuals

I worked on some nightclub visuals recently, which was a great change from my usual work. This was more a motion graphics type job, and involved a cloth like material streaming off a dancer as they performed traditional Chinese dancing.

I ended up simming about 8000 frames of particles, and then meshed the streams in Frost. Render times were pretty large, as the client required double HD. This is a small sample of the final result. I’ve changed the V-Ray shader in this version, as I wanted to try something else.

This is a render test at the double HD size, there are some Frost meshing issues with this test.

The particle count had to be increased to remove these holes in the mesh, but it was still a problem in the final render. This is partly down to the thin nature of the cloth like structures, as its not possible to increase the thickness of the mesh in Frost without changing the look of the streams. The only way to remove the holes is to massively increase the particle count.

Bluestone 42 Game Graphics

I was asked to provide the graphics for a video game in the TV show Bluestone 42. This is a quick breakdown showing the level building process I went through.

The brief was that I provide realistic current gen game graphics, so it was important for me to keep this in mind while building the level. I kept poly counts reasonably low, and used normal maps for extra detail. V-Ray was used to render the scenes, with cached GI. A game look for the shadows was achieved by using V-Ray shadow maps on a low setting

I delivered 17 shots for the show, based in 3 environments. The desert level shown above, a village level, and finally a recreation of the Bluestone 42 base.

I’ll upload some more videos showing my work on the show when I have a bit more time.

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Coke Building Commercial

Very pleased to have worked on this Coca-Cola ad for Nexus. I was responsible for all the hair and fur in the commercial.

There were 14 separate character hair setups, all sculpted in Hair Farm, and rendered in V-Ray. We were going for a photo real stop motion look, so the hair is designed to look more like nylon dolls hair than human. The scale of the styling and the hair strand thickness were designed to achieve this look. Hair Farm dynamics didn’t work at this small scale, so we used a Hair Farm link mesh, which was then rigged to drive any required motion for the hair. This also suited the hand stop animation feel we’d designed for the characters.

Nazi Mega Weapons: Super Tanks FX

A selection of shots from Nazi Mega Weapons: Super Tanks.

Didn’t have much time to get these explosions delivered. Just one day of setup, and then 1/2 a day per explosion for more setup, sim and render.

The fume sim is driven by a particle flow system. I wanted to have a strong petrol based explosion type, with an initial large blast, followed by multiple secondary explosions as other sources of fuel are effected by the heat of the first explosion.

To achieve this I used multiple fume particle sources with different settings, and could adjust the amount of fuel and heat I was adding to the explosion with each blast.

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Deadbeats Ghost – V-Ray Hair Test

So this is the same creature as shown previously, but I’ve spent some time working rendering the hair fully in V-ray rather than using a separate light rig, and the Hair Farm Renderer.

The hair is generated in Hair Farm, and then brought fully into V-Ray using the VrayHairFarmMod. The Hair Farm renderer is turned off and only V-Ray is used to render it. The V-Ray hair shader was used, with the white matted preset as a starting point. I still used Hair Farm’s Color Variation material in the diffuse which adds an individual colour to each stand. The Hair was also set to be opaque for GI, and shadows. Simplify for GI was also set.

Rendering hair can be problematic because of its potential to create noise in the image if the sampling is too low. The aliasing filter can also cause issues, so it took a bit of fine tuning to get this right.

Here’s the settings I used in the test:

Image Sampler: Adaptive DMC
Antialiasing Filter: Cook Variable set to 2.5

The DMC noise threshold is not as low as it could be, but I didn’t notice any major noise issues, so was set to 0.01

The scene is lit with 2 area spots, and an HDR dome light. Primary GI was Brute Force, with secondary set to Light Cache. Render times were pretty high using the HDR, but it was worth it for the final image quality. Without the HDR, and still using GI, render times were reduced by 3/4.

View fullscreen in HD for best results.

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