Use a simple script to achieve powder pile | Maya nParticle简单脚本实现粒子堆叠

10,573 Replies


Youtube

Maya nParticle only calculates friction/stickness between particles and rigid bodies, not friction is encountered between particles. My guess is the algorithm complexity is too high. Anyway there is two relative easy ways to fake the effect, according to my searching.

想要用一个一包糖粒堆在物体（对又是它..）上的片段，发现Maya的nParticle只计算粒子和Rigid body的摩擦力不计算粒子和粒子间的摩擦力（想来是算法复杂度太高了），所以不管怎么搞最终都会摊成大烧饼，并且还会不停的抽搐.. 查了下大概有两个相对简单的方法

1. hold particles with a invisible rigid body. 2. Use RealFlow, which seems to have much more handy control over particles

I’m not happy with either. 1 is lame. 2 too much trouble, have to get hang of another environment. If I must do scripting, I choose to learn mel.

So the algorithm is:

It’s unlikely to mess with friction as I guessed above. I tried to modify per particle mass to let them stuck in the space. Yea that works but they tend to be headbutted by other particles and flying around.. for science. Later I googled out it’s possible to control force field per particle, with attribute named “Field name”_”option name”. That is to say adding attribute “gravityField1_magnitude” to nParticle2 will grant you control over per particle gravity from the field.

On creation:

[php]
global int $freezeCap=5; //be completely frozen after the cap rounds
global int $gravityPP=500;
global float $dragPP=100;
global float $accelerationTrigger=15; //the speed parameter to trigger ‘I’m free again!", which leads to free droping.
global int $n[100000]; //how many times have the particle been locked
global int $preVel[100000]; //velocity of last frame
global int $locked[100000];

nParticleShape4.dragField1_magnitude=0;
nParticleShape4.gravityField1_magnitude=$gravityPP;

global int $init=1;
if($init==1) {
int $i;
for($i=0;$i<100000;$i++) {
$n[$i]=0;
$locked[$i]=0;
}
$init=0;
}
[/php]

Before dynamics:
[php]
int $id=nParticleShape4.particleId;
float $vel=abs(nParticleShape4.velocity);

//print("nParticleShape2.velocity "+$nParticleShape2.velocity+"\n");

if($vel>$preVel[$id]+$accelerationTrigger) {
$n[$id]=0;
nParticleShape4.dragField1_magnitude=0; //If it’s free again, unlock and erase record
}
else {
$freezeFact=$n[$id]/$freezeCap; //progress bar of locking
if($freezeFact>1)
$freezeFact=1;
$n[$id]+=1;
nParticleShape4.dragField1_magnitude=$freezeFact*$dragPP; //increase drag force depending on locking level
nParticleShape4.gravityField1_magnitude=$gravityPP*(1-$freezeFact)*(1-$freezeFact); //parabola is better according to experiment
nParticleShape4.velocity=<<0,0,0>>;
}

$preVel[$id]=nParticleShape4.velocity;
[/php]

The script is not bad to me.. adjustable parameters are handy. Time efficiency is acceptable (as a former ACMer, I can confirm this is O(n), can’t be better). 20 million particles * 100 frames cost my i7 half an hour. Not perfect but enough for bragging.
1. 弄个透明的动画的rigid body来把粒子圈起来。 2. 用RealFlow，我只用RealFlow模拟水，但是显然那它对粒子的控制比Maya厉害得多。

两个方法我都不高兴，1太不屌爆，2太麻烦，要做很多熟悉另一个环境的工作，且要写脚本，所以不如来学下mel。下了本书叫Maya Python — for Games and Film，翻了一百页发现Python在Maya上基本是庞大的workflow中工程师为了其他人方便写的maya程序，并且也要有mel基础，不是我要的。

总之，思路是：

想要计算摩擦力显然是不现实的，说过了。我先通过改质量的途径让粒子满足条件时失去质量以停在原地不受重力影响，停是能停住但是会被别的particle撞飞.. 非常科学。后来查到可以使用 <力场名>_<属性名> 的方式控制Per Particle的行为，即，给nParticle2添加名为gravityField1_magnitude的attribute程序就会使用它来控制它受到重力场1的magnitude。然后通过DragField让particle稳定。我在注释里详细说。

粒子生成时脚本：

[php]
global int $freezeCap=5; //be completely frozen after the cap rounds
global int $gravityPP=500;
global float $dragPP=100;
global float $accelerationTrigger=15; //the speed parameter to trigger ‘I’m free again!", which leads to free droping.
global int $n[100000]; //how many times have the particle been locked
global int $preVel[100000]; //velocity of last frame
global int $locked[100000];

nParticleShape4.dragField1_magnitude=0;
nParticleShape4.gravityField1_magnitude=$gravityPP;

global int $init=1;
if($init==1) {
int $i;
for($i=0;$i<100000;$i++) {
$n[$i]=0;
$locked[$i]=0;
}
$init=0;
}
[/php]

动态前的脚本：

[php]
int $id=nParticleShape4.particleId;
float $vel=abs(nParticleShape4.velocity);

//print("nParticleShape2.velocity "+$nParticleShape2.velocity+"\n");

if($vel>$preVel[$id]+$accelerationTrigger) {
$n[$id]=0;
nParticleShape4.dragField1_magnitude=0; //If it’s free again, unlock and erase record
}
else {
$freezeFact=$n[$id]/$freezeCap; //progress bar of locking
if($freezeFact>1)
$freezeFact=1;
$n[$id]+=1;
nParticleShape4.dragField1_magnitude=$freezeFact*$dragPP; //increase drag force depending on locking level
nParticleShape4.gravityField1_magnitude=$gravityPP*(1-$freezeFact)*(1-$freezeFact); //parabola is better according to experiment
nParticleShape4.velocity=<<0,0,0>>;
}

$preVel[$id]=nParticleShape4.velocity;
[/php]

个人感觉这个还不错，有很多参数可以控制，效率也还行（前ACMer表示这个就是O(n)..不能再低了），200万粒子100帧i7跑半个小时。显然不完美，蒙人没问题。

10,573 thoughts on “Use a simple script to achieve powder pile | Maya nParticle简单脚本实现粒子堆叠”

  1. Marissa

    Please let me know if you’re looking foor a writer for your weblog.

    You have sokme really good articles and I feel I would be a good asset.
    If you ever want to take some off the load off, I’d absolutely love to write some material for your blog in exchage for a ljnk back to
    mine. Please send me an email if interested. Cheers!

    Reply ↓
  4. what is billiards

    Oh my goodness! Awesome article dude! Thank you, However I am encountering problems
    with your RSS. I don’t know why I cannot join it.
    Is there anyone else getting similar RSS issues? Anyone who knows the solution can you kindly respond?
    Thanks!!

    Reply ↓
  8. pepek gratis

    Excellent goods from you, man. I have understand your stuff previous to and you are just extremely magnificent.
    I actually like what you have acquired here, certainly
    like what you are stating and the way in which you say it.
    You make it entertaining and you still take care of to keep it sensible.
    I can not wait to read much more from you. This is
    really a terrific site.

    Reply ↓
  9. Stella

    OMT’s area forums enable peer ideas, wһere shared mathematics insights spark love аnd cumulative drive for test excellence.

    Enroll tօday іn OMT’ѕ standalone е-learning programs and seе y᧐ur grades soar
    through limitless access t᧐ top quality, syllabus-aligned material.

    Іn a systеm wһere mathematics education һas evolved to promote innovation аnd worldwide competitiveness, enrolling іn math tuition mɑkes ѕure trainees гemain ahead bʏ deepening theіr understanding and application оf
    essential ideas.

    Eventually, primary school math tuition іs crucial fοr PSLE quality,
    as it gears uр trainees wth tһe tools to achieve leading bands and protect preferred
    secondary school placements.

    Comprehensive protection οf the ѡhole O Level syllabus in tuition guarantees no subjects, fгom collections to vectors, ɑre ignorｅd in a student’ѕ modification.

    Fⲟr thοsｅ pursuing Η3 Mathematics, junior college tuition ⲟffers innovative advice օn rеsearch-level topics
    tо master tһis difficult extension.

    Ꮤhat collections OMT aрart іs its custom-made curriculum tһat aligns
    with MOE ѡhile supplying flexible pacing, enabling sophisticated pupils tо accelerate thеir knowing.

    OMT’ѕ on-lіne math tuition lеts yοu change at youг own speed lah, so no mоre
    hurrying and your mathematics grades ѡill ceгtainly skyrocket gradually.

    Tuition programs іn Singapore offer simulated exams ᥙnder timed conditions, simulating
    genuine test scenarios fоr better performance.

    Review my webpage math tuition singapore (Stella)

    Reply ↓
  10. mostbet_momn

    Беттеры, отзовитесь кто откуда. То вообще доступ к аккаунту без причин закрывают, Денег слил на всяком говне и нечестных букмекерах пока чисто случайно не протестировал единственное место, где реально не кидают начиная от удобного интерфейса и заканчивая официальной лицензией. Всё летает как часы в любое время суток,

    Кому тоже актуально найти проверенное место для игры, обязательно сохраняйте себе этот официальный ресурс регистрация мостбет [url=https://mostbet-cwg.com.kg]регистрация мостбет[/url] Не ведитесь на дешевые лохотроны из рекламы, обязательно перешлите этот пост тому, кто тоже сейчас ищет нормальную контору!

    Reply ↓
  11. sex việt

    If you are going for most excellent contents
    like myself, only go to see this site every day since it offers
    feature contents, thanks

    Reply ↓
  13. Adrovia.Eu

    Rzeczowy tekst. Dużo praktycznych porad. Dziękuję że dzielisz się wiedzą.
    Zapisuję do ulubionych.
    Masz rację – sprawa aranżacji jest niełatwa. Przydatne podejście.

    Naprawdę przydatne. Szukałem podobnych porad właśnie tego.
    Super robota!

    Also visit my web blog :: Adrovia.Eu

    Reply ↓
  17. desitube.cc

    South hunsly adultBi hett mdom feom cons anal story multBoiswe adlt supr storeWatch hbbo documetaries ral sexIndependznt escorts surreyMusang c syrip 68Traci lords adul dvdCoboy gaay heayh ledgerBigg boob halloweenHaand
    bas thumb spica splintNaturally haiy thumbsRacxhel bigg boobsParaplegic fuckFreee lesbian aian sexx torture pornAtk natural
    annd hairy 14Africaan wojen hving sexAusralia aadult sexx toysBriney pusswy hoot spearWiife neeeds cumHoow to make bottfom uup roman shadesRetr bandeau bikini18th cebtury pornReed riover drag stripOffticial height off
    a midgetEigh tube prn frese vidsDoug huey is an assholeFree cunt poweredd byy vbulletinFreee
    chubby chasder bsar pics3d maturee animeReporrts bbisexuality teen boysWifes a cuum slut onn tubesHajry puussy picsNormql
    peni ldnght girthRouseau and pleasureSmalleszt penios contest howaard sternFrenchh nude modelPeeing iin diaperSex stylke varianceAtgractive miolf fucked oon sofaBoyy caftoon sexXxx sex pictuyre movieToop tewen stars picsAlewsandra ambrsio nudeAtlanta transexal escorrt annd backpagesMatture jspanese
    porno movieCrtoon ssex vidoePhoos oof nakeed meen andd womenBaii ling playbky nudeGroup ggirls blog nakedRoock
    vinttage teesNuude chihese manYouhng women havig sexTurrured clitPissiong shemape movies foor
    freeSex annd tthe othr womanAustralian handd jobLadette sex tapeClips oof
    faat women fuckedHailey young facialCrrazy gay maleGaay clubs llos angels
    caLatiha bbww analGayy film clihk clickWwww fre
    spanizh assBdssm ball injeUnderater handjobSpanked
    inn comicsSwollen guks vagimal discharye uteruis crampsFree interracxial sexx
    cartoonFogy bottom wichita ksBiig cocck shemae tbe videoFacial foor acxne skinBottolm liv wikiTooll free seex educationSunraa nudeMyths iin sexual dysfunctionsMature best friednds and sexTorrent hand job bunniesVaginhal renuvenation pk24Teenn
    lillianBikiuni custlmer videoAsss gqpe measureDeseene pornoFreee indtructional ssex videoPhhotos nudess womenPlumpers
    and biig cockDouuble headd vibratorGrls nudfe in texas ofvd9wuapt6ydcqyjnwi

    Reply ↓
  24. math tuition singapore

    OMT’s multimedia sources, ⅼike engaging video clips, mɑke mathematics сome alive,
    assisting Singapore students fаll passionately crazy ԝith it for test success.

    Discover tһe convenience of 24/7 online math
    tuition ɑt OMT, ѡhere engaging resources mɑke learning enjoyable and efficient fօr all levels.

    In Singapore’s rigorous education ѕystem, wһere mathematics іs mandatory ɑnd consumes аround 1600 hourѕ of
    curriculum time in primary and secondary schools, math tuition ƅecomes impoгtant to help trainees construct а strong
    foundation fоr lifelong success.

    Tuition emphasizes heuristic analytical аpproaches,
    crucial fօr dealing with PSLE’s challenging worⅾ issues that neeԀ multiple steps.

    By supplying considerable experiment ρrevious O
    Level documents, tuition furnishes pupils ѡith familiarity ɑnd thе capacity tо expect question patterns.

    Вy providing extensive exercise ᴡith past Α Level examination papers, math tuition familiarizes trainees ԝith
    inquiry formats аnd marking systems for ideal efficiency.

    OMT sticks οut with іts exclusive mathematics curriculum,
    diligently designed tо complement tһe Singapore MOE syllabus by completing theoretical spaces that standard school lessons mіght neglect.

    Gamified components make revision fun lor, motivating
    еvеn more method ɑnd causing grade enhancements.

    Tuition centers іn Singapore focus ⲟn heuristic methods, crucial for dealing witһ the tough ԝοrԀ pr᧐blems іn math tests.

    Feel free tօ visit mү homｅpage :: math tuition singapore

    Reply ↓
  26. live sex

    It is appropriate time to make some plans for the future and it’s time to be happy.
    I’ve read this post and if I could I desire to suggest you few interesting things or
    tips. Perhaps you could write next articles referring to this article.
    I want to read more things about it!

    Reply ↓
  27. Renate

    Wirklich guter Artikel. Jede Menge nützliche Hinweise. Großes Lob dass du
    dein Wissen teilst. Ich werde öfter reinschauen.
    Volle Zustimmung – die Frage des Wohnstils kann nicht einfach.
    Endlich mal Klartext.
    Echt inspirierend. Ich habe schon nach ähnlichen Tipps genau
    danach gesucht. Klasse gemacht!

    My site Renate

    Reply ↓
  28. Hassan

    Wertvoller Inhalt. Reichlich nützliche Informationen. Grüße dass du dein Wissen teilst.
    Ich warte auf mehr.
    Treffend formuliert – der Bereich der Wohnungsgestaltung kann anspruchsvoll.
    Hilfreicher Ansatz.
    Aufrichtig inspirierend. Ich suche schon nach solchen Informationen lange gesucht.

    Klasse gemacht!

    Here is my web page – Hassan

    Reply ↓
  32. evisa

    Fascinating blog! Is your theme custom made or did you download it from somewhere?
    A theme like yours with a few simple tweeks would really make my
    blog shine. Please let me know where you got your theme.
    Thanks a lot

    Reply ↓
  34. Bobby

    Bardzo dobry tekst. Mnóstwo wartościowych informacji. Dzięki za
    ten materiał. Polecam innym.
    Zgadzam się – sprawa wystroju potrafi być wymagająca.

    Przydatne podejście.
    Szczerze przydatne. Szukałam podobnych porad już jakiś czas.
    Pozdrawiam!

    My blog post Bobby

    Reply ↓
  35. Https://wiki.Rettungsdienstblog.eu/

    Hej, szukałem informacji o aranżacji i chcę powiedzieć, że temat jest świetnie opisany. Sama od jakiegoś czasu urządzam mieszkanie i takie porady bardzo się przydają. Pozdrawiam forumowiczów.
    Dobry temat. Z mojego doświadczenia dobór mebli ma ogromne znaczenie. Lepiej raz a dobrze.

    Review my website https://Wiki.rettungsdienstblog.eu/index.php?title=Jak_urz%C4%85dzi%C4%87_wn%C4%99trza_w_stylu_glamour,_kt%C3%B3re_naprawd%C4%99_dzia%C5%82aj%C4%85_na_co_dzie%C5%84

    Reply ↓
  37. A Levels math

    Thrօugh real-life study, OMT ѕhows math’s influence, assisting Singapore students сreate ɑn extensive love and exam inspiration.

    Established іn 2013 Ьy Μr. Justin Tan, OMT Math Tuition һas ɑctually helped countless students ace
    exams ⅼike PSLE, O-Levels, аnd Α-Levels with proven problem-solving strategies.

    Αs mathematics forms thе bedrock of logical thinking ɑnd vital
    analytical іn Singapore’seducation ѕystem, expert math tuition ρrovides the customized guidance essential tо turn obstacles іnto victories.

    Ꮃith PSLE mathematics contributing ѕubstantially tо total ratings, tuition supplies
    extra resources ⅼike model responses for pattern acknowledgment аnd algebraic thinking.

    Secondary math tuition lays ɑ solid groundwork fоr post-O Level гesearch studies,
    ѕuch аs A Levels or polytechnic courses, Ƅy mastering fundamental subjects.

    Junior college tuition оffers access to extra resources ⅼike worksheets ɑnd video descriptions, enhancing A
    Level syllabus protection.

    OMT establishes іtself aⲣart ѡith a curriculum tһat enhances
    MOE syllabus usiong collaborative ߋn-ⅼine forums fоr talking
    about exclusive math obstacles.

    With 24/7 accessibility t᧐ video clip lessons, үou can catch
    uρ ᧐n harԁ subjects anytime leh, aiding ｙou rack uр much
    bеtter in exams witһoսt tension.

    In ɑ hectic Singapore class, math tuition ցives the
    slower, іn-depth descriptions neеded to construct confidence fоr exams.

    Review mү web page – A Levels math

    Reply ↓
  38. Rogelio

    Hallo, ich bin zufällig auf dieses Thema gestoßen und ich stelle fest, dass das Thema hervorragend beschrieben ist. Ich renoviere seit kurzem mein Zuhause neu zu gestalten und jeder Hinweis ist Gold wert. Viele Grüße.
    Wertvoller Beitrag. Ich kann aus eigener Erfahrung sagen, dass die Raumgestaltung eine enorme Rolle spielt. Gut Ding will Weile haben.

    Reply ↓
  42. virtual

    Hello to all, how is the whole thing, I think every one is getting
    more from this web site, and your views are pleasant in favor
    of new users.

    Reply ↓
  44. 수원출장마사지

    Do you have a spam issue on this site; I also am a blogger, and I was curious about your situation; we have created some nice practices and we are looking to swap strategies with others, why not
    shoot me an email if interested.

    Reply ↓
  46. u888

    Definitely imagine that which you said. Your favorite justification appeared to be at the internet the simplest factor to be aware of.
    I say to you, I certainly get annoyed at the same
    time as other people think about concerns that they plainly don’t
    recognise about. You managed to hit the nail upon the top and outlined out the entire
    thing without having side effect , other people can take
    a signal. Will likely be back to get more. Thank you

    Reply ↓
  47. ataşehir Çıtır Escort

    Thanks for your marvelous posting! I truly enjoyed reading it, you
    happen to be a great author. I will ensure that I bookmark your blog and will come back in the foreseeable future.

    I want to encourage that you continue your great job, have a nice evening!

    Reply ↓
  48. Top rated online casino australia

    Amazing! Your site has quite a few comment posts. How did you get all of these bloggers to look at your site I’m envious! I’m still studying all about posting articles on the net. I’m going to view pages on your website to get a better understanding how to attract more people. Thank you!

    Reply ↓
  49. http://daoqiao.net/copydog/home.php?mod=space&uid=5352391

    Guten Tag, ich bin beim Stöbern hier gelandet und mir ist aufgefallen, dass es hier viele wertvolle Inhalte gibt. Ich gestalte gerade die Einrichtung neu zu und ich suche nach Inspiration. Grüße an die Forengemeinde.
    Spannender Thread. Aus meiner Erfahrung die Raumgestaltung nicht zu unterschätzen ist. Gut Ding will Weile haben.

    Reply ↓
  50. 19야동

    Hey there! Do you know iif they make any plugins to assist with SEO?
    I’m trying to get my blog to rank for some targeted keywords but I’m not seeing very good gains.
    If you know of any please share. Kudos!
    19야동

    Reply ↓

Leave a Reply

Your email address will not be published. Required fields are marked *