Help with cloud like platforms

[GingaNinja]

Hi, I am desperately trying to figure out how to make cloud like platforms where you jump up through them but don't actually land on them until you start falling again.

Could anyone help - I can post code if you would like and also I don't want it to be tile based either.

Thank you for any help in advance.

[ImprisonedPride]

If your jump speed is negative (sending you up) and you collide with the platform, do nothing.

If your jump speed is positive (sending you down) AND your 'feet' are above the platform, land on it, otherwise, do nothing.

[the--flash]

Dunno whether your game is tile-based, but tonypa did a whole series of tutorials on tile based games, and one of the sections is about clouds.

http://www.tonypa.pri.ee/tbw/

ImprisonedPride's method works, though.

[GingaNinja]

Sorry, I don't want any tile based and i've already seen Tonypa's and it wouldn't work with my engine.

I've tried the other suggestion and it works fine - however, when you reach the arc of your jump and just happen to be touching the top of the platform; it automatically snaps onto the platform and looks quite crude. I want it to be smoother if possible.

[ImprisonedPride]

You mean the frame where the sign of the fall speed changes from negative to positive? I suppose you could add a check to see if "adding" the amount of change in fall speed from the previous frame changes the sign back to what it was, and if so, you could ignore the hitTest on the platform.

Alternately you could also check to see if fall speeds NEXT frame will be crossing the top of the platform and react accordingly.

Finally, you could not check the top of the platform, but maybe a few pixels higher than that (like adding a 5px buffer above to check the "top" of the platform) which might reduce the snapping issue when the fall speed is near zero.

[GingaNinja]

Here is my .fla if it helps. Would you be so kind as to have a look at it for me please. If not then that's fine

http://www.sendspace.com/file/wuzpcx

[mr_malee]

http://soap.com.au/chris/attachments...CHARACTER9.zip

- changed it to the position of the player is defined by a number, not screen position. I'm pretty sure the accuracy of using the _x and _y of objects is much less than a Number object.
- added a checkCollision function to all objects instead of giving them their own enterFrame. This way you can control the execution of your code. Process player first (get updated positions) then process collisions, then render player to correct position.
- put all collision objects into an array.
- the cloud collision function uses a rectangle to define the collision boundaries, you then check the old position of the player and new position and see if the object passed through. If so, set the players position to the top of the platform.

[GingaNinja]

http://soap.com.au/chris/attachments...CHARACTER9.zip

- changed it to the position of the player is defined by a number, not screen position. I'm pretty sure the accuracy of using the _x and _y of objects is much less than a Number object.
- added a checkCollision function to all objects instead of giving them their own enterFrame. This way you can control the execution of your code. Process player first (get updated positions) then process collisions, then render player to correct position.
- put all collision objects into an array.
- the cloud collision function uses a rectangle to define the collision boundaries, you then check the old position of the player and new position and see if the object passed through. If so, set the players position to the top of the platform.

Wow thats overwhelming compared to what i have done - i only have one problem with it though - I wasnt really planning on having an array for the collision objects - I wanted all of the code contained within the movie clip so I could just drag and drop it on the stage and it will function correctly. I am trying to edit your code to accomplish this but gotta learn what a lot of it does first lol

[ImprisonedPride]

Turn the array of objects into an empty one arrayName = []; and then give all on screen objects a variable called objectType. For platforms, on their code frame you'd have objectType = "platform";. Then call this function once right at the start of the level:

function findCollisions() {
     for (i in _root) {
          if (     (typeof(i) == "movieclip")     && i.objectType == "platform") {
               arrayNameMaleeUsed.push(i);
          }
     }
}

It's not tested so I think it works, but it may require some adjusting. Replace the reference to _root with the name of clip that contains all your platforms, walls, etc. Basically this will allow you to use Malee's code and still be able to drag and drop platforms and walls onto the stage. Remember to only call it once, because calling it every frame will probably kill the player with a lot of obstacles on stage.

[mr_malee]

Wow thats overwhelming compared to what i have done - i only have one problem with it though - I wasnt really planning on having an array for the collision objects - I wanted all of the code contained within the movie clip so I could just drag and drop it on the stage and it will function correctly. I am trying to edit your code to accomplish this but gotta learn what a lot of it does first lol

I can say right now, that is not the best approach to creating a platform game, you will soon find yourself in trouble (performance wise and management wise)

IP has a good solution, maybe you could also add a "addCollisionObject" function to the root and then within the movieclips they call that function and pass themselves to it.

so your movie would have 3 frames:

1 - initialize base objects, arrays, variables
2 - movieclips on stage are added to arrays
3 - onEnterFrame starts and game runs.

[GingaNinja]

Turn the array of objects into an empty one arrayName = []; and then give all on screen objects a variable called objectType. For platforms, on their code frame you'd have objectType = "platform";. Then call this function once right at the start of the level:

function findCollisions() {
     for (i in _root) {
          if (     (typeof(i) == "movieclip")     && i.objectType == "platform") {
               arrayNameMaleeUsed.push(i);
          }
     }
}

It's not tested so I think it works, but it may require some adjusting. Replace the reference to _root with the name of clip that contains all your platforms, walls, etc. Basically this will allow you to use Malee's code and still be able to drag and drop platforms and walls onto the stage. Remember to only call it once, because calling it every frame will probably kill the player with a lot of obstacles on stage.

I can see what you are tying to do but it doesnt seem to be working -I just fall straight through!

Sorry if Im being too much of a n00b - I ain't used flash for time and a lot of this is quite new to me

EDIT:
And Mr Malee - im making a fighting game so i wouldn't really have to worry about performance and maintenance because the levels are only really small.

[ImprisonedPride]

Make sure you are correctly referencing both the array malee used AND the mc containing the platforms.

[GingaNinja]

Make sure you are correctly referencing both the array malee used AND the mc containing the platforms.

Well i've changed the array name that malee used and all my platforms are on the _root so that shouldn't need to change right?

Ive also put objectType = "platform"; in the code for the platforms.



Like I said I can see what you are trying to do but it just isn't adding the platforms to the array - it is not recognizing the typeof bit as far as I can see

[mr_malee]

it needs to be:

for (i in _root) {

	var ob = _root[i];

	if (ob.objectType == "platform") {
		platforms.push(ob);
	}
}

no need to check typeof.

[ImprisonedPride]

it needs to be:

for (i in _root) {

	var ob = _root[i];

	if (ob.objectType == "platform") {
		platforms.push(ob);
	}
}

no need to check typeof.

potatoe potatoh

[GingaNinja]

it needs to be:

for (i in _root) {

	var ob = _root[i];

	if (ob.objectType == "platform") {
		platforms.push(ob);
	}
}

no need to check typeof.

Okay it seems to work when I put findCollisions(); in the onEnterFrame functoin but as mentioned - this causes it to mess up and it runs really slowly. However if I put that function call elsewhere then it doesn't work at all.

[ImprisonedPride]

Okay it seems to work when I put findCollisions(); in the onEnterFrame functoin but as mentioned - this causes it to mess up and it runs really slowly. However if I put that function call elsewhere then it doesn't work at all.

Remember to only call it once, because calling it every frame will probably kill the player with a lot of obstacles on stage.

[GingaNinja]

That's what I did and it never worked - it only worked when I did what you told me not to do but after a while it lagged terribly.

Where should I be putting it?

[mr_malee]

like I said, you need 3 frames. Whats happening is the objects don't have the objectProperty when that loop is called. Their properties are set after the root code has executed. So, they must exist and be put into memory before the root code executes.

http://soap.com.au/chris/attachments...CHARACTER9.zip