View Full Version : Tutorial 2.2 - Constructing a Dynamic Setpiece

Logic Pack
11-05-2009, 03:09 AM
Tutorial 2.2 - Constructing a Dynamic Setpiece
By ConfusedCartman (http://www.lbpcentral.com/forums/member.php?u=118)

A dynamic setpiece is essentially a section of a level that changes its form based on any number of inputs. A Creator named jackofcourse is famous for this kind of level-bending - nearly all of his levels contain complex moving parts that work together to help (or hinder) sackboy - so if you're interested in seeing this on a large scale, be sure to look him up. In the tutorial itself, we'll be using the logic you have at your disposal in order to craft a short dynamic setpiece.


Pause the physics and build something like this. The main portion is three layers thick. The background is one layer thick and placed so that it's in the back of the main portion, glued in. Sackboy should have two total layers to move around on, with the third being filled by the background.


To the right of that chunk, build a deep pit. Add three platforms, keeping in mind that they will need to be able to move vertically. If in doubt, use the screenshot as a guide.


Connect these three platforms to the floor by stiff pistons. Set their minimum length to about what you see in the screenshot. The platforms in this screenshot are in the same position as they were in the screenshot before it, so that should help gauge where they go.


Move all of the platforms up to about here, and match the maximum setting to the current length of the pistons. Extend the right cardboard up so that it is higher than the highest platform, but still low enough to allow Sackboy to jump up to it from said platform.


Move the platforms back to their original position. Add a checkpoint before the gap. Although you can't see it in the screenshot (LittleBigPlanet's screenshot tool doesn't capture horrible gas), the pit is filled with horrible gas, up to about right above the two lower platforms. The goal is to ensure Sackboy cannot stand on the two lower platforms but he can still use the middle platform to traverse the gap. This step is optional, but players would rather die than get stuck and have to pop themselves to escape, so be sure to include something at the bottom that can kill the player.


Now we'll make a small puzzle that will activate these platforms. To the right of the platforms, carve out an alcove like so. The specifics aren't too important as long as you get the general shape and size right.


Add a one-layer-thick background to this room, matching the interior shape. Glue it in.


On the right wall of this room, add a little "catcher". Keep in mind its purpose (to catch small cylinders of dissolve) while constructing it. Make sure it's glued in place.


Add a small ramp to the top-left of the room, gluing it in place. This ramp will allow the previously mentioned dissolve cylinder to pick up a bit of momentum as it rolls down.


Build this "T"-shaped platform with one small bit of polystyrene at the bottom to allow Sackboy to grab on. Now, at the height it's currently at, Sackboy should be able to grab it without leaving the ground. If not, you'll have to adjust the length of the bottom part of the "T" to compensate.


Build one thin layer of glass that is the same length and width as the top of the "T" shaped platform. Glue it to the back of the platform itself. To do this, move the glass strip directly behind the top of the platform. Hold down L1 (this pushes the glass strip against the back of the platform) then glue it down. It will only glue against the back of the platform. This is a very useful technique for precise gluing, so play around with it when you have some free time.


Add in a rectangle of one-thin-layer glass. The purpose of this shape is to restrict the movement of the platform while still allowing it to glide back and forth fairly easily, so make sure the glass isn't glued to anything except the back wall! If it is, it will likely cause more problems.


Build a small one-layer-thick cylinder of dissolve. Add a magnetic key switch to the center of it, set it to On/Off, and connect the wire to the dissolve itself. Set the Radius so that when the cylinder is sitting on the platform, the radius is about two small grid spaces from touching the ground of this room. Feel free to move the cylinder to test it out. Afterward, add in a magnetic key somewhere on the dissolve as well. Make sure the two items are set to different colors so they don't interfere with each other. You may also want to pick a color that you don't usually use, to avoid conflicts later on. Capture this object into your popit - we will be using it in an emitter in the next step.


Set the emitter to emit the cylinder of dissolve somewhere over the ramp we built earlier. Make sure Max Emitted is set to ∞ and Max Emitted at Once is set to 1.


Place a grab switch on the platform's polystyrene. Set it to One Shot and connect it up to the emitter. Now, every time Sackboy grabs the platform, one of those cylinders will be emitted. If he releases and grabs again, the previously-emitted cylinder will be removed and another one will be re-spawned.


Close to the floor, add two magnetic keys of the same color as the magnetic key switch on the cylinder. Make sure that the radius of the cylinder does not detect these keys while the cylinder is on the platform. This is to ensure that if the cylinder falls from the platform, it will dissolve away instead of rolling off and interacting with the rest of the level.


In the previously-mentioned "catcher", add a magnetic key switch of the same color as the magnetic key on the cylinder. Make sure its radius is set to be just big enough to encompass the entire interior of the "catcher", without extending too far.


Add one of our permanent switches under the catcher and connect the blue magnetic key switch to it. Set the permanent switch to "directional", then connect it up to each of the platforms' pistons.


To help visually, I added a couple of LEDs. This isn't necessary, but it does help the player better see what's going on, so it might be a good idea.


Carve out a long slot in the floor of this room. This may look destructive, but we'll fix it in the next couple of steps.


Fill the slot with a two-layer-thick piece of cardboard, making sure its positioned so that the front layer is still free. Glue it in.


Add a little one-layer-thick "cap" to the right end of the slot, making sure it's glued in. We'll be adding a piston soon, and without this, the piston would disappear into the two-layer-thick cardboard behind this slot. It's just for aesthetics, but it helps players better understand what's going on in your level, so it's a good idea to include it.


Build a one-layer-thick "sliding floor" that stretches from the left part of the gap to the very edge of the floor that sticks out under the "catcher". It can be longer than that if you'd like, but no shorter or you risk the player falling into the slot.


Connect the cap to the "sliding floor" with a stiff piston. Set the piston's maximum length to the length it is currently extended to.


Move the "sliding floor" over until its left side is flush with the wall. Set the piston's minimum length to that distance. Connect the permanent switch (the one by the "catcher") to the piston that is responsible for moving the "sliding floor".


Unpause the physics. The platforms and the "sliding floor" should be retracted, looking something like the above. Keep in mind: when two objects are flush with each other and one is required to move past another (like our "sliding floor" and the slot it moves in and out of), sometimes they get stuck. We didn't run into any problems ourselves, but this issue is unpredictable. If you find that the "sliding floor" doesn't want to move in and out of the slot smoothly, try leaving just the tiniest bit of space on the top and bottom of the "sliding floor" by shrinking the square brush slightly before making it. This ensures that there will be enough room between the floor and the slot to have an effect, but not so much that the player will see a large gap.


Pause and unpause the physics (which adds a sort of "rewind checkpoint"), then solve the puzzle. To do so, you have to navigate the dissolve cylinder into the "catcher" by moving the "T"-shaped platform in sync with the momentum of the cylinder. If done correctly, the platforms should extend upward and the "sliding floor" should extend outward, covering the gap and allowing you to navigate up to the roof. After you've solved it, rewind until you get to the part right before you started solving the puzzle (so that everything is in its place).

At this point, you're done with the basic puzzle! Obviously, we only used one small piece of logic, but this tutorial was more about getting you to understand how to get moving parts to work the way you want them to. We do have a Tweak that you can tackle, if you're interested. It's recommended but optional, so whether or not you decide to tackle it is up to you.

Logic Pack
11-05-2009, 03:13 AM
Tweak #1 - Making Things More Difficult

For this tweak, we're going to be working on requiring the player to complete the task multiple times before the platforms extend upward. Adapting our current puzzle to this setup is surprisingly easy with our Dissolve-Based Counter, so lets get started!


First, pause the physics. Delete the Permanent switch and change the size of the "catcher" to make it seem as if the ball falls into an endless pipe. To enhance the effect, add a thin layer of cardboard in front of it so that the player doesn't see where the ball goes.


Drop in one of our Dissolve-based Counters. Make sure there are only three dissolve squares in the slot, so that once the task is completed three times, the switch will activate.


Change the blue magnetic key switch's output to one shot, then connect it to the Dissolve-based Counter's piston. Set the Dissolve-based Counter's magnetic key switch to directional, then connect that to the three vertically-moving platforms and the "sliding floor" we designed earlier.

Give it a try! If you followed our instructions, it will activate only after three dissolve cylinders were deposited. There are things we could do to improve this puzzle (as there almost always are) but that's another tutorial altogether. See if you can make improvements on your own.