SuperFly volumetric breath/water vapour shader (Not clouds)?



  • I was just wondering if anyone had experience with SuperFly volumetric shaders for water vapour. I'm trying to illustrate and perhaps animate a person breathing, either on a cold day, when water vapour condenses from your breath in a "cloud", or as the result of panting after heavy exertion.

    I don't want obvious cloud shaders, this needs to be more of a tenuous puff of vapour near the face which expands and dissipates.

    The boundary could be a sphere or ellipsoid or even a torus, but I need a shader which looks like vapour and can be varied between translucent opacity and transparency.

    Any suggestions? I've used volumetrics for gem stones and fluids, but never achieved satisfactory partial translucency, as in a cloudy, semi-opaque liquid.



  • Well, maybe I've picked the wrong cloud to climb aboard. Volumetric absorption doesn't really seem to be what I'm trying for, if I think about it for more than 30 seconds. Perhaps what I'm looking for is primarily volumetric scattering, and trying to leverage a solution from what I'd done before is not helpful...

    Let's see, ... there's a cycles ScatterVolume node. Maybe that's where I should start...
    0_1520605212602_Screen Shot 2018-03-10 at 1.11.33 am.png 0_1520605229445_Screen Shot 2018-03-10 at 1.12.17 am.png 0_1520605239069_Screen Shot 2018-03-10 at 1.12.52 am.png 0_1520605250952_Screen Shot 2018-03-10 at 1.13.32 am.png
    Hmm, adjusting the ScatterVolume Density does seem to give a useful dissipation effect on the "smoke ring" (just a squashed sphere with an inverse square falloff z-scaled deformer). That might do, if I scale the puff of breath up as it moves away and dissipates.



  • Ok, maybe this isn't too bad...



  • @anomalaus I've tried this before. I made this prop in blender to start with.
    0_1520615227845_breath 1.jpg



  • @ghostship how does it render? Could you get the same effect from displacement of a simple, high-poly cone?



  • @anomalaus this is the first shader I tried.
    0_1520615924349_Breath mat.jpg



  • @anomalaus the shader looks like this when lit with Poser lights: The problem is that it looks different or you can't see it at all depending on the lighting situation with the scene.
    0_1520616005958_Breath 2.jpg



  • @ghostship remind me not to let Andy blow smoke in my face, that looks toxic ;-) (but quite believable for smoke). Thanks for sharing your shader.

    Despite what I called my render (really only based on the sphere/torus shape), I'm really trying to simulate breath condensation, rather than exhaled smoke, so apart from trying to increase the turbulent/cloudy appearance and displace the outline with larger, random amplitude, I think I'm pretty close. But, of course, as you mention, so far I have only one sample of view angle and lighting to judge by.

    So, off to try the prop effects in a real scene, or two... Oh, and not to forget the puff of breath needs to decelerate as it expands and dissipates, not maintain constant velocity.



  • You could also try this one. It's emissive so you can see it in all lighting.
    0_1520616652101_Emissive Breath mat.jpg
    0_1520616715947_Emissive Breath 2.jpg



  • Panting


    Parented the prop to a Grouping object, so scaling affects the size and distance of the breath vapour, and rotation of the grouping object changes the vector which the prop traverses, rather than just it's orientation.

    ValueOperations allow linear animation of a single parameter to run the entire breath cycle, including inverse square deceleration of the vapour as it spreads and increasing and decreasing density of the vapour as it condenses and re-evaporates.



  • @anomalaus Really nice! just need to deform it a little so it is less regular but you are almost there!



  • @amethystpendant thanks. Here's where I've got to. No major changes with the prop other than adjusting the density profile for a faster onset. I'm happy that it looks like I expect water vapour to, rather than particulate smoke.

    Chilly Tunnel


    Default SuperFly render settings to minimise render time, so lots of fireflies.



  • Here's the prop (grouping object for placement, direction and scaling, and morphing sphere with animating volumetric scatter material). It requires the Poser 11 grouping object and primitive ball, as well as SuperFly materials. Just animate the Breath parameter linearly from 0 to 1 for each breath cycle.

    an0malaus Breath Prop



  • @anomalaus Thank you so much for this, I doubt I woill make animations, though you never know, but I'm sure the shader will be used, boiling pan / kettle etc!

    Amanda



  • I'm giving some thought to applying these props to an animation sequence, and while it's absolutely obvious how to deal with an essentially static figure, with only expression and minor limb movements animated, I'm not really sure how to go about major figure movement or orientation changes, in terms of prop placement. Does anyone have experience with a series of constraints in animation?

    Given the possibility that a single breath cloud may not evaporate before a subsequent exhalation, multiple instances of the breath props would be needed. In my current scene, I'm not parenting the grouping object to the figure's head, though it's placement is initially dependent, as I realised a turn of the head should not have any influence on the vector the breath prop continues to follow (using the obviously invalid, yet expedient assumption that the entire breath is emitted instantaneously). If it were parented, turning the head during the breath cycle would illogically move the breath prop to follow the head and would just look blatantly wrong.

    Yet I would want subsequent breaths to commence from the appropriate world location relative to the figure's head at that frame, so I'm thinking about how to achieve that with constraints. I suppose I could just have one set of breath props for each breath, but that seems completely wasteful of resources, when an individual breath prop would only be visible for a single, or small number of breath cycles, and then never be used again, whereas relocating and recycling a few breath props seems the obvious solution.

    So, each grouping object for a breath cycle needs to constrain itself to the figure's head's position at the current frame, and then hold that world position for the remainder of that breath cycle, rather than continuing to follow the constrained, head-relative position in subsequent frames. Unless I'm mistaken (and happy to be advised if so), this implies to me that I would need a constraint object parented to the figure's head, which can be constrained to at the first frame of each breath cycle. What I'm having difficulty working out is how to release that constraint and have the grouping object remain in place.

    How can I acquire the current frame position of an object and then transfer that position to another, static object which will maintain that position throughout subsequent frames, without resorting to Python scripting? I know that I can use a parent, zero relative position, unparent workflow to acquire a parent object's position on a temporary child object, but that process will kill or corrupt all previously set keyframed positions during the parenting and unparenting. It feels like I should be able to do this with constraints, but I'm not sure if that will work.

    Comments or advice would be most welcome, please.

    0_1520768175601_Screen Shot 2018-03-11 at 10.00.15 pm.png


  • Poser Ambassadors

    My first thought would be a particle emitter parented to her mouth.
    To deal with a previous breath still visible when it's time for another breath, I think it would be easiest to use a second particle figure/emitter.



  • @seachnasaigh okay, so that means a python script then, since I'm not aware of any particle emission system bundled with Poser. Any you'd care to recommend, before I just bite the bullet and write one to make use of the single particle per breath system I'm using, with SF Volumetric Scatter replacing a myriad of infinitesimal water vapour droplets?


  • Poser Ambassadors

    @anomalaus Bite that tasty bullet! P11 could use a current particle system.0_1520773283429_giggle.gif

    The last time I had need of particles in P11Pro, I ran Particles 3 in P7, saved the simmed particle figure as a PZ3 (scene), then opened that scene in P11Pro. It worked. I was able to render the particle effect in Superfly with. However, you can't re-simulate the Particles 3 figure in P11.



  • @anomalaus What you want is a constraint object at the mouth and another one for each breath object you want to animate. So lets say you want 4 breaths. You would need 5 constraint objects (Targets), Mouth, B1, B2, B3 and B4. So the Constraint at the mouth will move with the head and you start a breath object (say #1) with a constraint set to 1 at the mouth and the other constraint for that breath B1 set to 0. As the animation plays along the time line you make the mouth constraint move towards 0 and B1 move towards 1. This will cause the breath object to move between these two points. The only issue you will run into is as the mouth constraint moves it will change the path of the breath object. You can get rid of this problem by making a total of 8 constraints, M1 & B1, M2 & B2 etc. Make your figure animated and place a Mouth constraint at the location the mouth is on the frame you want to start a breath. Do the same at each location and you will have 4 breaths that will move along their own paths without changing the tracking because the mouth moves. Downside to this is you have to plan out your action ahead of time, or be prepared to move the Mouth constraints if you change the animation.



  • @seachnasaigh unfortunately, nothing older that P8 (PPro2010) will even run on macOS Sierra 10.12.6, since Apple orphaned hybrid Motorola/Intel architecture binaries, so I can no longer run Particles 3 or Wierd Juice's Drops.

    @richard60 I like the idea of constraints. I just need to verify that my theory of how to acquire the current frame position of a parent object and apply it to a child before unparenting that child will preserve the parent's position on the child, and a one constriaint per breath cycle plus another for the animated mouth position should work and be calculable by a python script, which can then be re-executed if the animation is changed.