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[Skyrunner]

I understood as much as you did. >.>

Still, my current status is:

That moment when you are struggling with some concept and suddenly it dawns on you. >_<

Of course, I still have a lot of other things to figure out, like how to find the limit in computer-world, or what the heck "split the fluid proportionally to the corresponding
difference ΔI_n and apply the respective directional derivatives from lower cells" means, or how I project a vector to ... another vector? And what's "integrating the amount of fluid in the definition of the function F(x,y)" supposed to mean? T_T Also, I think they're missing a variable definition.

So.... one.

[Siquo]

I understood as much as you did. >.>

Still, my current status is:

That moment when you are struggling with some concept and suddenly it dawns on you. >_<

Of course, I still have a lot of other things to figure out, like how to find the limit in computer-world, or what the heck "split the fluid proportionally to the corresponding
difference ΔI_n and apply the respective directional derivatives from lower cells" means, or how I project a vector to ... another vector? And what's "integrating the amount of fluid in the definition of the function F(x,y)" supposed to mean? T_T Also, I think they're missing a variable definition.

So.... one.

Integrating (and this is a metaphor:) is getting the area under a line or volume under a plane. It's the exact opposite of a derivative (as in, if you integrate and then derive you should arrive at the same function, give or take some constants ).

[Skyrunner]

I do know what integration and differentiation are. I just don't know what the author means by "integrate the amount of fluid in the definition of the function F(x,y)" and how it relates to fluid in adjacent cells interacting with each other. :<

[Siquo]

Assuming you have the height as some kind of wave-surface, integrating that wavesurface for a specific area gives you the amount of water in that area, and it's relevant to know that compared to the amount in the cell next to it?

I'm just guessing, I'll need the context

[Skyrunner]

(In case anyone's wondering, here is where I'm getting all my problems from. I wholly blame alway for introducing me to this...)

This part? xD I'm not quite understanding how the acceleration vectors obtained move the water from place to place, while avoiding the problem of local minima... The phrase in question is near Equation 13.

And I need to sleep soon D: Too little time for plumbing the depths of advancedish math and physics...

Also, since you're looking at it, do you know what the variable T might be in equations 14~16?

[alway]

Well, most of that paper seems to have entirely overly complicated equations. It could be a transpose operation. Entirely unnecessary for code, but it may make it technically more mathematically correct. As for programming, we don't care whether it's a row vector or column vector.

The delta (triangles pointing up) just means 'change in.' In those equations, I(x,y) = H(x,y) + K * F(x,y), where H is soil height and F is fluid height. Delta I in a grid is the difference between the I values between 2 points; in this case the current point and a neighbor.

For splitting the fluid proportionally, you find:

Code: [Select]

sum = 0
for each neighborPoint,
{
delta I = I(thisPoint) - I(neighborPoint)
if (delta I > 0)  //downward slope
sum += delta I
}
for each neighborPoint,
{
delta I = I(thisPoint) - I(neighborPoint)
if (delta I > 0)
proportion(neighborPoint) = delta I / sum
else
proportion(neighborPoint) = 0
}


[RedKing]

I like it when SMBC gets contemplative from time to time.

Spoiler (click to show/hide)

[miauw62]

The exchange went really well! Hell, *all* the teachers are complimenting our class because we did so well.

And the Walloons were friendly too. BUT HOLY FUCK THAT SCHOOL WAS HUGE.

[MonkeyHead]

The 6 Nations starts this weekend. Bye bye any kind of "doing stuff" weekends, hello a 6 week long binge of rugby  .

[Korbac]

The 6 Nations starts this weekend. Bye bye any kind of "doing stuff" weekends, hello a 6 week long binge of rugby  .

Were you the kind of bloke who went mad when we got the GSlam last year?

[MonkeyHead]

The 6 Nations starts this weekend. Bye bye any kind of "doing stuff" weekends, hello a 6 week long binge of rugby  .

Were you the kind of bloke who went mad when we got the GSlam last year?

Maybe a little  . I am old enough to remember the horrible 80's and 90's, and am more than familiar with the boom and bust that is Welsh rugby, so like to try and keep my expectations low.

[Bauglir]

It turns out Domino's has a built-in limit on the number of toppings you can put on a pizza online. My scheme to set every cheese to triple is a failure.

[Sirus]

It turns out Domino's has a built-in limit on the number of toppings you can put on a pizza online. My scheme to set every cheese to triple is a failure.

You're happy that your scheme failed?

[MonkeyHead]

I suspect that post was written by Bauglir's arteries.

[Bauglir]

Even if the scheme failed, there's still a lot of cheese. Triple mozzarella, feta, double parmesan/asiago, double provolone. There's also some anchovies and spinach in there.