*Algo... oummph, I swallowed my tongue!*

[toolpot462]

Algodoo is unable to reproduce a simple arc. I upped the friction and varied the density. I staggered the round bricks. I placed two blocks at the base and fixed them to keep the foundation from sliding. Amazingly, I cannot get a simple arc to even stay up.

I also tried to reproduce a simple orbit scenario. Two small orbs orbiting a larger orb, starting in perfectly simetrical positions and velocities. The system breaks every time. Sometimes the two orbs revert to the same direction of orbit. Sometimes they even end up bumping into each other. The system never carries on as it should mathematically.

Collision detection is laughable. I'm sorry, but at this point this software should be much better. I'm sad to see that almost no effort has gone into improvement after the initial milking of the cash cow. A big hand to the developers.



By the way, the sensorship on this forum is shameful. Can't even say doo doo as one word without it being replaced with idiocy.

[toolpot462]

Scratch that, you can say doodoo, just as long as algo doesn't go before it. That's pathetic.

[electronicboy]

Before you start slating a program, at least give us the scene you are having problems with.

There is censorship on the forum, as to protect any younger members of the website.

Ps, double posting is pathetic, there is a edit button there for a reason.

Are simulations in Algodoo accurate and correct, or is this just a toy?

Algodoo is indeed a digital toy, and nevertheless simulations are of very high quality, using cutting edge scientific methods for multiphysics simulation. However, there are some things to keep in mind:
The time step in Algodoo is fixed to 1/100 second (100 Hz), so any modeling of real-world physics happening at shorter time scales will be hard to reproduce. Typically this also means that the physics occuring on very short length scales is hard to resolve with this timestep, so we don't recommend sub-centimeter physics at all. This scale limitation also holds for fluids.
When simulating a scene, Algodoo is solving a large system of equations using numerical methods. In order to ensure interactivity, the solution is approximate and this may lead to artefacts in certain cases.
The simulation engine in Algodoo is rather complex, and as with all software it may contain bugs. If you have found an inconsistency in the simulation that you believe should not be there, you should report this!
We do our very best to make sure Algodoo has high fidelity physics, but legally Algoryx has to issue the usual statement that: The software is provided as is, without warranty of any kind, express or implied, including but not limited to the warranties of merchantability, fitness for a particular purpose and noninfringement of third party rights. In no event shall the authors or copyright holders, Algoryx Simulation AB, be liable for any claim, damages or other liability, whether in an action of contract, tort or otherwise, arising from, out or in connection with the software or the use or other dealings in the software.

However, if you check on Algobox, there are sevaral orbital scenes, and they work fine.
I suggest you post the scene so we can get an overall community review.
We can't look into the issue if you don't provide all the relevant details.

And, if you had any brains, you would understand that collision detection while in real-time motions won't be brilliant anywhere for a long time. I don't know ANY software out there that has perfect collision detection, and still has reasonable performance with many objects.

[Kilinich]

Rude trolling detected.
Leave him alone, electronicboy, don't waste your time.

[Kilinich]

By the way, the sensorship on this forum is shameful. Can't even say doo doo as one word without it being replaced with idiocy.

oh... I've just re-read post about your contest ( I guess your attack is related with it).
I think it's really a shame for algodoo community to answer newbies like it was. Too rude, too unfriendly.
Sorry for that, toolpot.

[jon_joy_1999]

There is censorship on the forum, as to protect any younger members of the website.

we both know that's a bunch of bullogna. I've seen posts that contain words, which would make my grandmother cringe, from the very people you are claiming to protect.
so don't. just don't.
you can say "yes, we censor that combination because, really, that's an offensive and disgusting method of referring to Algodoo."
or
"if you want to use that term to refer to Algodoo, we don't want to hear what you have to say, and the censor lets you know that."
but don't couch the censorship in "protecting youth" when the censorship is ineffective at blocking worser words

[electronicboy]

Okay, I was in a depression filled rage, which I guess I released in a rant post.

The censorship is mainly in-place in places other then the living room, that is really the only area where I let the rules down a lot, but, that's like a tradition with the Algodoo/Phun forum admins.

But, I like to keep the other sections of the forums looking more professional, I guess I'm not exactly great at enforcing it all the time in the other areas.
My main admin skill is removing all the spam on here, which is actually more sucessful since I've started then it was, I'd say over 90% of spam posts are actually blocked, you guys only ever see the small amount that escapes past the set up.

But, let's get back on topic.

[jon_joy_1999]

right, back on topic, arches seem to work fine for me, http://www.algodoo.com/algobox/details.php?id=67851 but I'm a bit rusty on my orbital mechanics, and I'd bet dollars to donuts that yours are just as bad as mine.

[toolpot462]

By the way, the sensorship on this forum is shameful. Can't even say doo doo as one word without it being replaced with idiocy.

oh... I've just re-read post about your contest ( I guess your attack is related with it).
I think it's really a shame for algodoo community to answer newbies like it was. Too rude, too unfriendly.
Sorry for that, toolpot.

It's pretty typical to call someone like me, who is complaining about how shitty a software still is, a noob. But I was here since the days of Phun. I used to love this software. I even know a tiny bit about thyme. Then I was turned off from it for a while, and now that I've returned, I am sorely disappointed to see how unsuccessful the software is at reproducing actual phenomenon. I get that it's a toy, but I'm just not too interested in experimenting with elements in an environment that doesn't really make sense.

As for that contest, it was a reprise of a contest I opened in the Phun forums BEFORE paradigm (i think it was paradigm) opened his. I was only moderately active, but I was coke5 then.

[jon_joy_1999]

It's pretty typical to call someone like me, who is complaining about how shitty a software still is, a noob.

considering that your Here2There Contest was your very first post on this forum, you are a newbie.
considering your nonconstructive complaining, whining, and being a pretty much a sissy at the beginning of this thread, you also are a noob. if you are indeed this coke5 guy you claim to be, it's your fault you are being called a newbie.

[toolpot462]

It's pretty typical to call someone like me, who is complaining about how shitty a software still is, a noob.

considering that your Here2There Contest was your very first post on this forum, you are a newbie.
considering your nonconstructive complaining, whining, and being a pretty much a sissy at the beginning of this thread, you also are a noob. if you are indeed this coke5 guy you claim to be, it's your fault you are being called a newbie.

You've really got to out yourself as a non-constructive complainer to complain about someone else's non-constructive complaining.

[jon_joy_1999]

You've really got to out yourself as a non-constructive complainer to complain about someone else's non-constructive complaining.

oooo a tu quoque argument. fail.
either admit that you're not smart enough to figure out the limitations of Algodoo and ask for help,
or go away with your tail between your legs like you did before.

[TC42]

If collisions are bothering you, turn up the sim.frequency to 10K, and there is one other variable to change, but I forget its name.

--mildly-constructive-passive-agressive-moderate-complainer attempting to aid non-constructive argument about non-constructive complaining--

[toolpot462]

You've really got to out yourself as a non-constructive complainer to complain about someone else's non-constructive complaining.

oooo a tu quoque argument. fail.
either admit that you're not smart enough to figure out the limitations of Algodoo and ask for help,
or go away with your tail between your legs like you did before.

I haven't done that at all. That would denote shame or defeat. I withdrew in the frustrated realization that, much like now, the conversation was turning into a pissing contest. The fact remains that I have evaluated the limitations of the software and am simply not interested in using it anymore, because it sucks. So far, as a response, you've called me sissy, noob, mentioned that I "fail", referred to me as "not smart", and, best of all, implied that I am as a dog submitting to a superior. Bravo, kid, you're not half-bad at being an insulting dickhead. You'll go far on these forums, since that seems to be a prerequisite for seniority.

[toolpot462]

If collisions are bothering you, turn up the sim.frequency to 10K, and there is one other variable to change, but I forget its name.

--mildly-constructive-passive-agressive-moderate-complainer attempting to aid non-constructive argument about non-constructive complaining--

Thanks, I might try that.

[Kilinich]

I am sorely disappointed to see how unsuccessful the software is at reproducing actual phenomenon. I get that it's a toy, but I'm just not too interested in experimenting with elements in an environment that doesn't really make sense.

Arch: Open /lessons/arch.phz
Collision problems:
1) try to increase simulator frequency sim.frequency = 200
2) try set direct solver for collisions (it will remove penetration) sim.directContactSolveAll = true
3) give me scene so I can see what's wrong

[jon_joy_1999]

I haven't done that at all. That would denote shame or defeat. I withdrew in the frustrated realization that, much like now, the conversation was turning into a pissing contest. The fact remains that I have evaluated the limitations of the software and am simply not interested in using it anymore, because it sucks. So far, as a response, you've called me sissy, noob, mentioned that I "fail", referred to me as "not smart", and, best of all, implied that I am as a dog submitting to a superior. Bravo, kid, you're not half-bad at being an insulting dickhead. You'll go far on these forums, since that seems to be a prerequisite for seniority.

to set the record straight, I didn't call you a sissy, I didn't say you fail, for the former, I said you were being one, which implies the ability (and the suggestion) to not be one; and for the latter your tu quoque argument is fail; if you feel that means you fail, well that's your opinion to make, and finally I gave you the option of admitting that you're not smart and asking for help, or going away like a dog who is being ejected from the pack.

it is apparent that your statements of "I cannot get even a simple arc to stay up" are caused by your own inability to use the software appropriately, by the number of people who successfully use Algodoo, myself included. finally, the fact that your very first post referenced your inability to directly insult Algodoo in a derogatory manner, the fact that you have only made statements that are not cooberated by actual scenes where you display the failures that you experience, and the one scene that I offered that proves arches work, and went completely ignored by you, leads me to conclude that you don't want help, and you don't want things to work, you just want to troll, and be a douche; and, if it were up to me, you would be, at the very least, removed from the community for being unproductive

consider that when judging me on how I treat you

[toolpot462]

to set the record straight, I didn't call you a sissy, I didn't say you fail, for the former, I said you were being one, which implies the ability (and the suggestion) to not be one; and for the latter your tu quoque argument is fail; if you feel that means you fail, well that's your opinion to make, and finally I gave you the option of admitting that you're not smart and asking for help, or going away like a dog who is being ejected from the pack.

it is apparent that your statements of "I cannot get even a simple arc to stay up" are caused by your own inability to use the software appropriately, by the number of people who successfully use Algodoo, myself included. finally, the fact that your very first post referenced your inability to directly insult Algodoo in a derogatory manner, the fact that you have only made statements that are not cooberated by actual scenes where you display the failures that you experience, and the one scene that I offered that proves arches work, and went completely ignored by you, leads me to conclude that you don't want help, and you don't want things to work, you just want to troll, and be a douche; and, if it were up to me, you would be, at the very least, removed from the community for being unproductive

consider that when judging me on how I treat you

Great speech, chief.

[scene]67889[/scene]

By the way, your sig doesn't make sense. Without mentioning binary, you might as well be saying you don't know 10 from 2.

[Kilinich]

Nothing to complain, really.
Well-known limitation of any physics sim.
Same for Box2d and others.

1) Perfect geoms stack - to avoid it you can just select object and press righ/left arrow, that will move geom a little bit (half of pixel). It will never happened during sim time, it's only works then you specially arrange geoms. No problem here.

2) Arch - that's just your fault. It should fall in the way you construct it. If you google it and find some pictures, you will see it's not so opened.

3) Piston - Too thin, will penetrate deep and break, no doubt. To avoid it - increase sim.frequency (like I did) or make better piston. You can add big invisible borders for example.

[scene]67890[/scene]

[toolpot462]

Nothing to complain, really.
Well-known limitation of any physics sim.
Same for Box2d and others.

1) Perfect geoms stack - to avoid it you can just select object and press righ/left arrow, that will move geom a little bit (half of pixel). It will never happened during sim time, it's only works then you specially arrange geoms. No problem here.

2) Arch - that's just your fault. It should fall in the way you construct it. If you google it and find some pictures, you will see it's not so opened.

3) Piston - Too thin, will penetrate deep and break, no doubt. To avoid it - increase sim.frequency (like I did) or make better piston. You can add big invisible borders for example.

[scene]67890[/scene]

Maybe you're right about the arch, and I'll admit I was overreacting. I guess I'm overly picky about little issues (e.g. I don't care for Skyrim because characters repeat their lines too much). As for the stacking, I know that perfect geometries stack, and they should. The problem is that the circle on the square doesn't. It falls off almost immediately, or at least it did with me.

[jon_joy_1999]

the circle falls off because it has a non-zero velocity, at load it's velocity is -0.000013516803, 0.000021194341
and it's position doesn't help things, the circle is at -4.0, 0.66411269, and the square (or diamond) is at -3.9999995, -0.29289329, 0.0000005 meters off center.
for the arch, Kilinich is right, if you want a freestanding arch you may be interested in a parabolic arch.
as for my signature, the first time I saw it was in a FORTUNE cookie, in it's original binary form, and I didn't get it. years later I was enlightened by someone who was/is smarter than I am and I felt so stupid I laughed, thus I wrote it this way

[jon_joy_1999]

for extra giggles, if you set up the circle exactly on the peak of the diamond and zero it's velocity, it will still rotate on the tip (albeit slowly, changes apparent only over periods of tens of minutes)

[Kilinich]

Well, if you want to solve "perfect stack" problem once at all - add following script in console:

Code: Select all

Sim.airSwitch = true;
Sim.windAngle = {(system.time*10) % (math.pi*2)};
Sim.windStrength = {math.sin(system.time*10)}

That will add tiny wind force which breaks any stack.

[toolpot462]

the circle falls off because it has a non-zero velocity, at load it's velocity is -0.000013516803, 0.000021194341
and it's position doesn't help things, the circle is at -4.0, 0.66411269, and the square (or diamond) is at -3.9999995, -0.29289329, 0.0000005 meters off center.
for the arch, Kilinich is right, if you want a freestanding arch you may be interested in a parabolic arch.
as for my signature, the first time I saw it was in a FORTUNE cookie, in it's original binary form, and I didn't get it. years later I was enlightened by someone who was/is smarter than I am and I felt so stupid I laughed, thus I wrote it this way

The circle has velocity because I accidentally let the scene run a little before uploading. I noticed that when I saw the arch was a little warped. If you delete the circle and put one in the same spot using the grid to make sure it's in the right place, it falls to the left every time (for me)... even when I replace the square. If the culprit is that the square shifts its center position when I rotate it, that would still be the software - placing a square in a grid and rotating it exactly 45 degrees should produce a pefrect balance point for the circle, not something that's .0000005 meters off. I doubt that's the case, anyway - since the circle gained velocity it must have moved about that much.

edit - I actually got it to work. The same exact process. Not ten minutes ago, I put a square on a point in the grid, rotated it 45 degrees, and placed a circle directly above it. The result was that it would fall to the left every time. So I took the square and repositioned it to see if rotating it did in fact displace the center. It worked. What I actually find irritating is that I can't reproduce the same faulty result with the same exact process (rotate square, place circle above). It works every time now. I don't get it, honestly.

[Kilinich]

edit - I actually got it to work. The same exact process. Not ten minutes ago, I put a square on a point in the grid, rotated it 45 degrees, and placed a circle directly above it. The result was that it would fall to the left every time. So I took the square and repositioned it to see if rotating it did in fact displace the center. It worked. What I actually find irritating is that I can't reproduce the same faulty result with the same exact process (rotate square, place circle above). It works every time now. I don't get it, honestly.

You've done pretty hard job to find those issues maybe better to put that energy into good scenes?
Stack with boxes not always working because of contact position calculation precision.