Version 0.256 brings a number of minor changes and fixes along with two more parts that let you customize vehicles in new ways. I'll focus on the two new parts, with the full changelist below:

CAMERA MOD AND FIRST PERSON

First Person view is finally possible in Instruments of Destruction thanks to the new Camera Mod part. Has it been worth the wait? So far I'm going to say no. The game isn't really designed around FP view, so the effects don't look good from up-close. You can customize a lot about the First Person view, including the FOV, turning limits and speed, and where it appears relative to the part. In general I expect this to only be used for specific weapons/modes of a vehicle, and I don't plan to use it for anything else. Of the existing cabs, only the first 3 have decent interior models, with the Tall Cab and Standard Cab being the best ones. Not sure I'll add interior models to the other cabs. It depends on whether I need them, and when/if I add custom mesh overrides per part/type for vehicles.

Alternatively, you can use the part to offset or override the other camera modes, with different settings for both Follow (the first 5 values) and Iso/Orbit camera modes (the next 5 ISO values) If you set it to Override Cab Pos, it ignores the cab(s) and uses the part position/orientation instead. Otherwise it functions as an offset. If you set it to Always On, it ignores the input. Otherwise the strength value of the input can be used to modify how fast the offsets are applied once activated (this doesn't apply to FP view).

SOUND MOD

The vehicles in Instruments have 10 looping sound slots. Any part with a Sound Override setting (wheels, lasers, pivots, pistons, etc) affects one of those looping sounds, and changing the Sound Override changes which slot is affected by that part. That hasn't changed. But it's important to realize the 10 looping sounds exist, as they are what the Sound Mod part affects. Each Sound Mod can affect 2 looping sounds/slots. Let's break down 1 slot and the various parameters:

Slot 1 (or 2): This is the looping sound SLOT, named for the default sound that is played there and what normally affects that loop. There are always 10 slots, though the sounds are generally silent unless a part causes them to change in volume/pitch. This is the most important parameter because it affects what you are editing/changing. If you have 2+ Sound Mod parts modifying the same slot, only 1 of them will work.

-Sound Effect: This is the audio sample that is used for that slot. When you change the SLOT above, this will change automatically to the DEFAULT sound effect (the default pitch/volume will also be updated). There are 10 default looping sounds (same names as the slots), then 20 more looping sounds to choose from. A lot of them are similar, but I think that's ok because the pitch in particular affects the sound character more strongly than might be obvious at first.

-Pitch: This is the base pitch for the looping sound. 0 means it's played at the default pitch (100% speed) for the sample. At -0.75, it's playing at 25% speed (aka 2 octaves down), while the max pitch is 2.00 (aka 300% speed 2 octaves up).

-Dynamic Pitch: If there's an input set for the [+] value (top left for slot 1, top right for slot 2), that input is multiplied by the dynamic pitch and ADDED to the base pitch value. So how much it affects the pitch depends on the base pitch. If the total pitch value gets to -1 or lower, it essentially stops the sound.

-Volume: This is the base volume for the looping sound. This is straightforward compared to pitch, though volumes above 1 don't do anything by default. 100% is the max volume, but because the loops are affected by other parts or dynamic volume, values above 1.0 are still potentially useful.

-Dynamic Volume: If there's an input set for the [UpArrow] value (bottom left for slot 1, bottom right for slot 2), the dynamic volume is multiplied by the input strength, and then that adds to the part-based volume before multiplying by the base volume to get the final volume. If no part/etc is affecting the volume, then it's a bit simpler: Input Strength x Dynamic Volume x (base) Volume = Output Loop Volume.

There's also a TEST IT button for each slot. That'll play the whole loop once using the base Pitch/Volume settings. Some loops are longer than others, but in-game it's harder to tell that (because they loop).

NOTES: A couple of the slots (Engine1 and Engine2) are affected by the vehicle's speed and cab settings. Some of the slots also have their pitch affected differently based on the dynamic part parameters. There's too many variables to list them all here, but keep that in mind if you just using the Sound Mod to override the base loop sounds and not control them directly. Different slots will sound slightly different (and Engine1/2 are affected by speed and the Cab Engine Volume setting). There is also no default smoothing for the Sound Mod part input stuff, so you'll need Output Modifiers/etc on the inputs if you want to do that kind of thing.

VERSION 0.256 FULL CHANGELIST
Added new part: Sound Mod - customize the various sound loops the player vehicle uses (10 loops)
Added new part: Camera Mod - enable FP cam or offset/rotate the camera (based on the camera mode)
Added optional outputs to most weapons (except lasers)
Added F11 third mode for collision rendering (blue = normal, red = no_collide, green = treads, yellow = tread tracks)
Added 6 new particle type variations for Particle Effects part
Added two new regions for custom islands (and changed Compound + Test Island region)
- Also made it possible to affect exposure/saturation/contrast per region
Added material override on physics modifier and overlapper
Improved how highlighting works in build mode so it's easier to pick between 2 nearby parts (slight distance penalty for current selected one)
Allow small thruster and foot/foot xl to rotate
Added a function to select duplicate parts in build mode (Shift+Y by default)
Fixed low-speed bonus push (and gravity) no longer being used for powered wheels (all sizes)
Fixed: PgUp/PgDn not using new rot increments
Fixed last 4 colors not loading correctly on restarting in build mode
Added another check to remove duplicate selections of a single part in build mode
Fixed wave generator with loops disabled still essentially looping
Fixed not reselecting the right part when playing and returning to build mode (for close/overlapping parts)

The focus continues to be on building lots of unique vehicles for the upcoming campaign. I'm definitely burnt out to some extent, but feel compelled to keep working on vehicles (have around 50 at various stages). I want to start working on more maps soon, but need to add some new terrain generation tools first (hills/paths in particular are not fun to build currently) and I've been starting to think about how to rearrange build mode's UI more. Still don't have everything worked out in my head in that regard, so it probably won't happen yet.

At some point I'll need some beta testing on the new set of vehicles and maps, but that's still a month or more away. I had been hoping to get the campaign done before the Steam Summer sale, but that's looking less likely because good vehicles just take so long to do well, and I have no reason to believe maps will be much faster. On the plus side, I plan to polish about 10 vehicles to essentially final quality, and if I don't find anything significant to add/improve/change, I'll finally move on to non-vehicle work.