Forging on Sandbox

oO HYPH Oo · Dec 16, 2009

I can guarantee this is not only me, but when ever you forge on sandbox then save and end, when you start the game up again are objects slightly lifted on one side? (most noticeably Double Walls and most of the Block choices) I would love to know if there is anyway to keep this from happening. Its extremely annoying and I would like to know if anyone else is experiencing this annoying problem.

Thanks for viewing

AceOfSpades · Dec 16, 2009

oO HYPH Oo said: ↑

I can guarantee this is not only me, but when ever you forge on sandbox then save and end, when you start the game up again are objects slightly lifted on one side? (most noticeably Double Walls and most of the Block choices) I would love to know if there is anyway to keep this from happening. Its extremely annoying and I would like to know if anyone else is experiencing this annoying problem.

Thanks for viewing
Read More ...

This happens with any kind of wall piece, though I have never seen it happen dramatically with anything other than wall pieces. Unfortunately, there is no very easy way to solve it.

Bungie posted an explanation to it a while ago:

Bungie said:

Quantum Mechanical Rules Rule!

Those prone to flipping and rotating Forge's building blocks around their various axes have noticed that after a save and quit, the blasted slabs, partitions, and chutes occasionally end up shifting around and gettin' all "jiggy with it" (to invoke the parlance of 1998). So, just what maniacal and twisted conspiracy scheme have you unwittingly stumbled into, both literally and figuratively? Step into our office.

Well, "our office" is a bit of a stretch. We roped Jon Cable into it, our resident really smart guy who can do maths and such. The next portion of the update is on him. If you're interested, here's the explanation of exactly what's going on, and what you can do to smooth out your Forge experience with Sandbox.

Enter the Engineer

The Problem

When using double walls (or some other objects) to create a "floor," sometimes the objects become "bumpy" after saving and reloading the map.

The Cause

There are a near-infinite number of possible orientations that an object can be placed in. While you are editing a map, the objects are allowed to be in pretty much any orientation. When we save the map, we quantize the orientation in order to save space in storage. What this means is that the orientation you get when you load the map might not quite be what it was when you saved it.

Specifically, we store what direction the object's 'up' vector is pointing, and a rotation around that vector from its default position. When you first create an object in forge, its up vector is pointing straight up, and its rotation is zero. If you leave the object in a straight-up position, we use a special quantization method that preserves more precision for the rotation.

But if you tilt it (on its side, for example), then more of the storage space has to be used for that direction, and the rotation can lose precision. What this means is that when you are creating a floor out of walls, it's using the less precise method. The good news is that it's usually easy to predict which way the quantization error will go.

"Why can't you fix this?"

This problem is really inseparable from the way we store Map Variants on the disk. If we change the way the maps are encoded, then all the content saved in the old method could become invalid. It's a complex problem, and complexity means high risk. And risky changes are not something you want to make in a patch to a console game.

The Forge engine was built before we ever knew that maps like Foundry and Sandbox would exist. And this problem, of course, has been present since day one. It only now became apparent because people are building truly amazing maps and demanding more fidelity out of Forge.

"How about some good news?"

As outlined above, you should leave objects pointing 'up' if you can. If possible, create your floor out of double boxes instead of double walls. No effort, no bumps!

If you must use double walls for the floor, pay close attention to the location and direction of the helper gizmo (the blue/white orb that shows the origin of the object). When saved, walls placed horizontally tend to rotate such that the "forward" end of the gizmo is pointing slightly downward. You can use this to your advantage by placing walls that are end-to-end rotated 180 degrees from each other, so that both edges will be either high or low. Walls placed side-by-side should have the same gizmo orientation. See the following diagram:

Blame Stosh

Again, this is an issue that only crops up when you are rotating objects around their Z-axis, and most commonly, when shifting objects out of their initial orientation (i.e. laying a wall onto its side). The easiest solution is to make such shifts to orientation as sparingly as possible, or if you must, to simply follow the diagram Cable has laid out, juxtaposing the objects based upon the "gizmo," so that any variation you come across becomes uniform and therefore, less noticeable to players who traverse your map.

Yanking the network cable from the back of your Xbox 360, as some have suggested, does not resolve this issue.
Read More ...

Rorak Kuroda · Dec 16, 2009

That was a nice read. And now it makes sense! It only happens on sandbox because of it's massive size! If they had released each level of sandbox as an individual map, so that there was less data space used in the map. Then it would be more accurate, like foundry. Well, at least now I know. And it sounds like if you save often, the problem is less severe.

I sure hope this is fixed in Reach...

oO HYPH Oo · Dec 16, 2009

Thanks this helped a lot

Forging on Sandbox

oO HYPH Oo Ancient

AceOfSpades Talented
Forge Critic Senior Member

Rorak Kuroda Up All Night
Forge Critic Senior Member

oO HYPH Oo Ancient

Share This Page

Forging on Sandbox

oO HYPH Oo Ancient

AceOfSpades Talented Forge Critic Senior Member

Rorak Kuroda Up All Night Forge Critic Senior Member

oO HYPH Oo Ancient

Share This Page

AceOfSpades Talented
Forge Critic Senior Member

Rorak Kuroda Up All Night
Forge Critic Senior Member