Cloth Sim for the Farmer's Coat

So manually animating the coat didn't go so well.  Instead I've created a low resolution version of the lower half of the coat mesh,  put the armature, then the sim on that, then a solidify modifier on top of that.  To connect the high resolution coat to the low resolution sim mesh I use the normal armature deform for the top half of the coat (arms etc), then use the low resolution mesh with solidify modifier as a mesh deform cage for the lower half of the coat.  You need to do all sorts of weight painting and multi-modifier tricks to get the two to play nicely together, then you need to have a doubled up copy of the armature for the coat with copy transforms otherwise you'll run into a dependency cycle (this depends on your rig of course).  If you're going to use cloth simmed objects linked into files as groups with proxied armatures you need to then link in the cloth sim object and the collision objects again after you've done your usual group linking.  Overly complex I know, but it works... just.

Rigging Done

He's multi coloured in proxy form to help me spot mesh intersections.  The coat was an absolute nightmare to rig but now I have a fairly nice fake wind effect using displacement textures and animated textures, all controllable at animation time.  Time to start animating.

Say What Again: Facial Rigging

I primarily designed this rig around subtlety of expression and emotional nuances, obviously.  First full 'stop staring' style rig I've built, quite happy with it so far.  I rigged his mop-top as well so I can push it out of the way when you need to see the brows.  Did the crow and the dogs facial rigs as well  and completed the bike rig yesterday (with moving chain) as well as working up a fake wind sim system using displacement modifiers.  Just the farmer to finish off with then animation with UV unwrapping on the side.

Click What? Wing Rigging Revisited

So a few weeks back I demoed a folding wing ring based on Jared Reisweber's notes.  It didn't look much like a crow though - it was more of a soaring wing type.  I spent most of today pushing verts around and working with shape keys to get the fold even better and solve the distortion problems at the extreme poses.  I'm using a solidify modifier post-armature on the feathers to take give them some thickness - I had to separate them out from the rest of the mesh after binding. Most of the above bones will be hidden at animation time leaving 4 main controls per wing and 8 tweaks for follow through and puffing out etc.  Not sure what I'm going to run with for simming yet - maybe just animated displacements.

Wing Rigging Revisited

Half a crow with a folding wing.  The animation is a quick pop from shape to shape but it does show that there are hardly any ugly intersections at long last!



I started off with Jared Reisweber's Excellent Wing Rigging Tutorial then subdivided each individual feather's bone into a chain to help animate follow through and flex in the wing.  I added some flex controls for each group (primaries, secondaries and tertiaries) and wrangled the rig into a folded up position, and a couple of tweak controls to manually adjust the angle bisection used to fold all the feathers up.  I baked the animation from open to folded out to 3 shapes (a half folded, three-quarter folded and fully folded) then spend a few hours vertex pushing to make sure there were no severe feather intersections.  I used the blend from shape tool to smooth out irregularities between shapes caused by my vertex pushing.  I've still got quite a lot of reshaping to do on the rest of the body. and head then finally some decisions to make about the rest of the rig.  When I get the whole rig completed I'll post it up on blendswap.

In other news Chris Perry's 'The Incident at Tower 37' has finally been released online. I had the pleasure of being an intern at BitFilms out in Western Massachusetts for three months last summer. I realised after watching 'Tower' on vimeo that in my three months at BitFilms I never found the time to sit down and watch the whole film end to end (I was busy working on Bassam Kurdali's production, 'Tube'). While the visual style isn't entirely to my own tastes, 'Tower' is certainly a very powerful and intelligent piece and it's great to see the play counts soaring - Chris' film deserves every bit of exposure it's getting. Evan's fantastic score really completes it so make sure you've got your speakers turned up!

Quick Walk Cycle and Python to Mirror a Cycle

I started out aiming for John Travolta's Saturday Night Fever walk to staying alive but I quickly ended up with far too many keys and too snappy and exaggerated an action for a cycle.  I realised I needed to change the rig a bit to get the movements I needed so I stripped it right down and worked up this basic walk cycle just to test the changes work.

I also wanted to work with only half a cycle and be able to have a script mirror it for me.  I coded this quick python timesaver.  Basically just select all the bones you have animation on and enter the start and end frames into the script.  Eg. You have a stride on frames 1 to 21 and you want the mirrored stride to be placed on frames 21-41 so you enter start_frame=1 end_frame=21.  Be warned the script will purge any modifiers you have on fcurves (its lazy at the moment) and replace them with a simple cycle modifier so your pair of strides (on 1-41 in the example) continue looping forever.

import bpy

start_frame=1
end_frame=21

def set_frame(sf):
    bpy.context.scene.frame_set(frame=sf)
    bpy.context.active_object.update(scene=bpy.context.scene)
    bpy.context.scene.update()

for each_fcurve in bpy.context.active_object.animation_data.action.fcurves:
    for each_modifier in each_fcurve.modifiers:
        each_fcurve.modifiers.remove(each_modifier)
each_frame=start_frame
while each_frame<=end_frame:
    set_frame(sf=each_frame)
    bpy.ops.pose.copy()
    set_frame(sf=each_frame+(end_frame-start_frame))
    bpy.ops.pose.paste(flipped=True)
    print('copying '+str(each_frame)+' to '+str(bpy.context.scene.frame_current))
    bpy.ops.anim.keyframe_insert_menu(type=-4, confirm_success=False, always_prompt=False)
    if each_frame==end_frame:
        break
    set_frame(sf=each_frame)
    bpy.ops.screen.keyframe_jump(next=True)
    each_frame=bpy.context.scene.frame_current
#kill fcurve mods and add a cycle mod
for each_fcurve in bpy.context.active_object.animation_data.action.fcurves:
    each_fcurve.modifiers.new(type='CYCLES')       

Au Soleil at the London Underground Film Festival (LUFF)

I'm really happy to have heard from the London Underground Film Festival that my short 'Au Soleil' will be screening at the Horse Hospital next Saturday the 4th December, as part of their programme Around the Compass Rose: Human Geographies on Film.  'Au Soleil' was nominated for the technical achievement award at CAM*ERA earlier in the year.  It seems like ages since I finished work on this film, and though with hindsight some of the technical work isn't as strong as I would have liked, I hope it goes some way to proving that as a medium animation has more to offer than just tired/banal overworked childrens' entertainment.  Tickets available here £5 or £3 concessions, showing with 'Wild West', 'Faith Hope and Greenland', and 'Those Who Live Off the Dead'.

In completely unrelated news, Campbell Barton did a terrific job last week of bringing blender's rigging tools slightly further out of the stone age by fixing the infamous bone roll bug (which has been in blender for nearly as long as I can remember).  It seems that all of the devs have been completely oblivious to it, and no riggers have ever got round to reporting it as it was fixed just hours after I reported it!  Not only that, but Campbell has also added a few more options to the menu giving a choice of which axis to align to (+Y for  a leg IK chain for example).  Commit notes are here for anyone interested: 1 2 3.

Rigging the Sidewinder Desert Snake

The desert snake basically has a continuous sine wave running throughout its body, apart from the tail and the head which are partially free - the head tends to stay fairly level but still inherits some of the rotation from the body wheras the tail flips loose.  For the continuous sine wave, rather than using a wave modifier on a curve and relying on keying the speed (clumsy at best - I'd rather key the offset but then with speed set to 0 the wave disappears and further adjusting wave width during the animation isn't possible, unless you choose to scale the curve to change the wave width but then you get into more problems!) I drew a simple sine wave with a path, arrayed it many times, curve deformed it into a circle then applied the circular curve deform and set the path to be cyclic (on U).  I then converted my circular wavy path to polygons and extruded it out (with shift-Z to constrain scale to X and Y only).  I built a simple FK armature each of whose bones began and ended on the wavy surface, running round with a slight circular bend.  Below the start and end of each bone I put an empty which was shrinkwrapped with Z project to the wavy surface.  Each bone then has a track to constraint aimed at the empty nearest its tail.

I then use a second of chains of bones to convert this wavy (but curved) motion into a wave in a wave in a leaning plane (roughly the XZ plane rotated 45 degrees about Y) by copying only their local X rotation and making sure the bones in my second chain have their Z axes pointing towards the vector (0,1,1).  Then a third chain of bones tracks to the tail of its double in the second chain with maintain Z up set.  A fourth chain is used to add a user specified rotation in the world Z to each bone (for example a curve in the snake).  This has to be done in a separate chain containing copies of the third chain's bones rotations as rotating any bone in the third chain disrupts all of its children's track to constraints!)

A final few bones are used to add non-automated animation to the head and tail.  The width and height of the waves can be controlled by scaling (the parent of) the large rotating wavy disk in the world X or Z axis (there are some empties in between with maintain volume constraints to move the chain of empties which the first chain tracks to into the right position), and the rate of progress of the wave down the snake's body is controlled by rotating the wavy disk.

Now down to animating, at long last.



Birds and Fish

Quick Crow Flight Cycle

Might give it another go with a simpler setup when I get a moment.  Its still a struggle to get the wings completely folded up.  Rerigged the shark with a much simpler setup to get the simple sine wave propagating nicely, he's still a little dead for now though!

Updated - thanks to Frankie Swan for some great tips.

Bone Roll in Blender

It's well known that setting bone roll to Z-axis up in blender often doesn't work well, if at all.  If you find yourself having to set bone roll manually using Ctrl+R then this script might help you out.  Tab into bone edit mode, select the bones you want to roll, copy and paste the below script to a text editor, set your target roll vector as new_z_axis_vector in the script below (at the moment its set for z up) and hit run script.

import bpy,mathutils,math

new_z_axis_vector=mathutils.Vector((0,0,1))

for each_bone in bpy.context.selected_bones:
    new_x_axis=each_bone.y_axis.copy().cross(new_z_axis_vector)
    if new_x_axis.copy().angle(each_bone.x_axis)>90:
        new_x_axis=(-1)*new_x_axis
    previous_z_angle=each_bone.z_axis.angle(new_z_axis_vector)
    roll_adjust=each_bone.x_axis.angle(new_x_axis)
    each_bone.roll+=roll_adjust
    if each_bone.x_axis.angle(new_x_axis)>0.01:
        each_bone.roll-=2*roll_adjust

Of course the correct rigging practice is to make sure the bone roll of all the bones in a chain is such that the z axes vectors of all the bones are in the same plane so you might want to set new_z_axis_vector to something other than (0,0,1) or world z, for example a leg IK chain might need a value of (0,1,0) to make all the bone z-axes point forward.

Disco Guy - Character for the mood change walk exercise

Disco Guy: Rig and Wire

Some of the texture painting's not perfect but in the end I was pretty happy with how the rig turned out.  I have IK/FK switching on arms and legs, free/fixed hip choice, stretchy IK body with volume preservation and a nice B-bone torso, as well as clavicle deformers to keep the chest shape.  On the hands I have palm fan controls and finger spread/fist controls as well as individual finger curls.  Not too bad for half a days rigging and weighting.

Shape keys yet to come, only the eye controls are done for the face so far.  Not sure if I'll bother with custom bones as I know the rig inside out and spent a while sorting out layers.  Sadly the 32-bit PC in the studio can't cope with deep shadow buffers and hair without running out of RAM very quickly.



Painting the Fear and Loathing Fish

slowly going insane...

Spent the last 3 hours painting seamsless textures and bone weights (this ones an FK only rig... I'm running out of time).  At least the fish can now deform into shapes like this, and blow bubbles thanks to instanced metaballs on a particle system emitting from his cigarette!  He has a nice irradescent glow which changes colour as he turns round courtesy of blender's underused 'magic' texture mapped to the reflection channel.  Animation starts tomorrow!

Fish Modelling

Hunter S Thompson Herring

4 hours modelling

Great White Shark

3 hours modelling

(incl 1 hour of teeth vertex pushing!)

2 hours texture painting

(incl 1 hour of messing around with Photoshop 3D)

2 hours rigging and weighting

Some half cooked models I built in a rush for this weeks anim exercise (fishes with character).  The shark's got a nice spline IK rig (a spline for the back and for each of the big flippers), but thanks to blender's outgrown deps graph, it has more than twice the number of bones it would need in maya.  At least the modelling and texture painting in blender kicks the socks off maya.