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Do anyone know how to make the effect in the falling sand example https://dl.dropboxusercontent.com/u/...andexample.mfa
But without pasting the objects into backdrops?
I want the sands to be actives all the time so if you would want to start moving them again you could, but they would also stack up like this if falling on each other.
I tried to never paste them as backdrops but then they dont stack on top of each other. Do anyone know? https://dl.dropboxusercontent.com/u/...sandactive.mfa
In your example you aren't testing for overlapping between sand particles which is why they don't stack on top of each other. Despite noticing this issue, I still haven't figured out a way to solve your problem.
Keep in mind that your program will have to check every particle of sand every 1/50th of a second to see if there is still an obstacle below it. If you can think of a way to limit this and only check when the sand actually needs to fall I'd definitely do it.
Yes I tried to check for overlap but that just made them act strange, like stopping in midair.Quote:
Originally Posted by gkinfinity
Maybe it would be possible to use some flag that turns on if a sand lands on the ground, then if a sand is overlapping a sand that has this flag on it also stops.. so sand only falls when it is not touching another sand that has its flag on.. i dont know. This mostly makes me confused. It should be doable though? I could maybe just use box2d instead but I really would want this to be compatiable with other runtimes besides exe and flash.
MMF's physics object should be able to do this for you. It can handling objects on top of objects and all of them constantly active to changes in their environment. Unfortunately it's an object I never could wrap my head around, it's a bit complex, but if you can suss it out it should be able to do all this for you.
Wow, that was beautiful, but I can see how it could get out of hand.
The only thing I can think of is to find a way to detect clusters of grains in certain patterns. Then, delete all the grains in a cluster and replace them with an active object that looks like the cluster of sand. If the sand has to move again, replace the large active with the tiny ones again.
There has to be some sort of limit in place or it will slow things down. Is this a vital part of the game? Is there anyway to make this look good through animation alone?
Quote:
Originally Posted by Outcast
Is there anyway to make this look good through animation alone?
Hmmm, if the level is tile-based, and the tile slopes have set angles, it might be possible to make realistic animations portraying sand flowing from one tile to the next.
But basically it is not possible to do this exact things without using the paste to backdrop thing?
Yes i would think it could be possible, but i believe the core problem her is the sheer number ofQuote:
Originally Posted by Outcast
A) Objects on screen ( Slowdown? Upper limit? )
B) Collision checks per frame ( i think there actually is a limit to how many checks can be made at the same time, and the collision checks are demanding )
Maybe an constant ForEach loop through the SandParticles might be feasable and work?
If not allready on, using Box Detection instead of Fine Detection might improve performance also.
It would be nice to get it to work first, performance can come later :)Quote:
Originally Posted by King_Cool
Are you familiar with the built in 'Collision Mask Lag' problem?Quote:
Originally Posted by Outcast
That is waht is causing them to float in mid air im 99,9% sure.
The 'Collision Mask Lag' problem only happens with Object to Object collisions/ overlaps, not with Object to Backdrop.
...
However ther is a nice solution to this.
The Sand Particles are Pixels...
What you need to do is, do custom 'Box Coordinate Collisions' ( or in this case even simpler, custom 'Single Pixel Collisions' ) instead of the built in collision system.
This was there is no 'Collision Mask Lag' at all and collisions are pixel perfect and accurate.
...However this introduces another problem...
'Instance on Instance Collision', how to differentiate between the instances...?
Maybe this might not be a problem with the ForEach, i dont know i havent tried...
However it is the 'Collision Mask Lag' which is the problem, assuming you are using built in collision/ overlap checks.
It is possible, the Physics Object can do it. There is an example in there which uses it which has loads of objects all colliding off each other and fully functional.Quote:
Originally Posted by Outcast
Do you mean box2d? The point is I am trying to do it without any object that is not supported by all runtimes :/Quote:
Originally Posted by Paul_Boland
I am still wanting to do this, but with bigger objects. Like instead of sand it could be stones. So when one stone hits another it needs to drop to the side if there is space. Do anyone know of a formula to use for this? I would like to just use Box2D really, but not if that is not planned to be ported in the near future.. :/
1
If you want the particles to NOT be pasted as Obstacles ( which disables them from moving ever again ), you will have to handle the Collision Mask Lag issue, to make the Particles correcly interact so that the basic system works.
Fortunately, someone ( dont remeber who ) did find a solution to the collision mask lag problem.
The solution to the CML problem is to ( 1 ) move the Particles ( 2 ) Destroy them and create new Particles in their place ( this will uppdate all collision masks to the Objects current possitions ) ( 3 ) Do collision checking
Once you have done this you will have a system, exactly like the example mfa, where each single pixle Particles move through a Grid System and interact/ react to eachother.
2
Now that you have a working system where Particles progress through a 1x1 based grid system, you need to resize the grid system to, lets say, a 32x32 based grid system.
So instead of using 1x1 Square Particles, you use 32x32 Square Particles as collision masks, and you can super impose/ attach different graphics ( like round rocks ) ontop of the Masks.
However with this new 32x32 based grid movement system, the Object or Particles will move in increments of 32x32 kinda ( if you can visualize it ), which doesnt look to good.
At this point you simply, as the Particles move, store the Particles old and new coordinates in the 32x32 Grid System and create a smooth movement from point A ( old position ) to B ( new position ) inbetween each MovementStep/ each time all particles move 1 step.
...
Sorry for being confusing.
Hm I am not sure I understand how to execute this though :/Quote:
Originally Posted by King_Cool
OLD. You can look at the example on my website. After you see the example you will know.
Marv
I uploaded an example in the first post. I basically want the falling sand but to be able to interact with it. But I dont really need those small sand corns. Hm you could say I want to achieve what you can achieve with Box2D in simulating stones. They dont need to have the same fancy physics, but if there are 20 stones they should at least be able to be dropped down and stacked and falling to the sides if there are room. It seems so simple, but I have no idea how to do it even half good without Box2D :SQuote:
Originally Posted by OldLongDragon