Mobile Bases Preview

So, based on the previous poll, you guys mostly wanted to see NWO mobile bases. Good news is I do have a working preview of that, the bad news is current engine limitations means it will be pretty janky, for the time being.

As you can see, there is some strangeness going on visually, namely odd shadow alignments, and the fact that the hull doesn't bob up and down with the leg movements. To get into greater detail, the engine's current method of rendering shadows is extremely basic - shadows are just a separate series of frames that are overlaid onto the ground. This might work in a more simple 2D RTS, but given the 2.5D nature of DORF - where all assets are 2D sprites, but the game world itself is 3D - this won't really work. I've mentioned it before but we do plan on eventually implementing a total revision of the way light and shadows in the engine work, which will allow for lights to cast shadows onto other objects realistically, despite the 2D graphics, though this is a little ways off. The bobbing effect will be much easier to implement, seeing as the engine already includes a way to do this, however it needs some slight tweaking. Currently the bob effect will affect the entire object, so if it were used here, the legs would dip up and down along with the hull, which isn't useable. 

An additional note is that the legs are rendered separately from the hull. This allows use to reduce the sprite sheet size, since the four legs in the structure above are part of the same sprite sequence. These legs will also be used for all NWO mobile structures, to avoid the massive workload of having to create new animations for every single building, and (once again) to avoid further bloating the game's already large sprite sheet.

Of course, there will also need to be revisions to how the engine handles things in regards to walking structures deploying and creating units when static. To give some gameplay insights, NWO production structures, while mobile, will still need to be constructed via worker units, and will need to deploy to function properly. Think of them like Terran buildings from Starcraft, except they walk instead of fly. Also note that you can't just park these next to the enemy base and start pumping out units, since you will need to establish a supply chain to them to ensure that they actually have the resources to pump out units in the first place.

As you may have guessed, there's not just visual issues, but also some jank with the actual functional mechanics of walking bases. Pathfinding logic will need to be reworked to allow for units that are multiple tiles in size - currently, while infantry are smaller than a single tile (each tile can contain five infantry units, using subcell logic), vehicles can be no bigger than a single tile, in terms of collision size. So these massive walking structures (as well as other large units, such as Heavy Tanks and naval warships) will often clip through eachother and other objects during gameplay, until this new multi-tile unit collision logic is implemented.

There's a few other issues, too:

As you can see, the infantry seems to just slide down the ramp when created. This is due to an oversight that units granted a ZOffset when moving in or out of buildings (in case you want them moving up or down stairs, or in this case, a ramp), which results in them being considered as airborne by the game, and thus no animation is played until they reach the ground level. While not a massively complex issue, this is just one of many problems that will have to be overcome to get these walking bases working.

One more thing to note is not *every* NWO structure will be mobile. Their arsenal will include things such as walls, gates and static defensive structures, as well as a few support structures meant to be built quickly and cheaply.

That's all for this update, but look out for additional updates regarding implementing more NWO base buildings and structures.

- Henske