Sep 26, 2022

Engineer Alpha - aaronworcester

As you may have noticed there was no log last week. This was because it was international talk like a pirate day and I was off being minorly injured on a sailboat (these two events are entirely unrelated). So this week I have a Megalog for you all about one of my favorite areas, fluids.

When I first started planning out what I wanted the features for version 0.4 to be fluids didn’t even make it onto the list. There were many other things I wanted instead, but as I started making those features, I realized that I needed to sure up fluids before I could go any further on all the other things. Using the lessons (and code) from the rotation system, I set out to make a fluid system.

When I first started making Engineer Alpha a couple years ago, I conceptualized and started implementing a system for fluids. This original system was complicated, unintuitive and very messy. It was a system that I could not make sense of how it worked as the programmer so there was no way the average player could. I decided to throw that system out and start, essentially, from scratch.

If have been following these logs you may have guessed that I did not study Computer Science or Software Engineering in college or even Game Design. I studied Mechanical Engineering, with an emphasis on Fluids and Thermals. So fluids is an area of the game that is very important to me and I would not be happy if it didn’t work the way I wanted. There was a fair bit of fighting my own nature to make it something the average player would understand and I may have pulled out the old textbooks at one point, but in the virtual world I make all the rules.

When making any complicated game system it is a good idea to set some design goals to help guide you, here are some of the things I wanted for the fluid system.

Pressure gradients not "blocks"
No sloshing
Easy to understand when/how much fluid will flow and when it won’t
Fluid higher up/closer is more valuable
All fluids are incompressible
Pre-compute as much as possible to ease CPU load
Work with the other systems already in the game (e.g. rotation)

In my original design for fluids a pipe would simulate pressure by assuming that all fluid within it was at the same pressure. Creating what I would call a "block". If two pipes were connected that had different pressures fluid would flow from high pressure to low pressure. This is a seemingly intuitive model but not how things work in the real world when it comes to pipe flow. I am not particularly strict about making sure things match up exactly with the real world as that might make them unfun, but I do like them to be grounded in reality. In the real world pressure is lost over a distance as a gradient and where two pipes meet their pressures will be equal. This is how I made it in game. If you connect pipe B to pipe A the pressure at the beginning of B will be set to the pressure at the end of A. The pressure at the end of B will then be calculated based on a number of factors: length of the pipe, change in vertical height of the pipe, the material the pipe is made of, the fluid in the pipe, etc. Every pipe or building that has a fluid input and output will have these properties and calculate its own output pressure based on all of these factors.

Pressure is displayed to the player as a single numerical value and if a tank has multiple outputs all of them will have the same pressure. If there are multiple inputs it will use the smallest non-zero value for the input pressure when it calculates the output pressure. To keep fluids from sloshing back and forth all flow is monodirectional meaning it must always go from output to input. I have tried to simplify fluid flowing as much as possible so any pressure above 0 will cause fluid to try and flow at the maximum possible rate.

Pipes and other fluid transfer related buildings come in many different materials. Every material has its own properties for max pressure, distance pressure loss, and flow rate. Pressure is simply clamped to the maximum value and if you build a system that exceeds the max there is no penalty. There was going the be a leaking system or pipe breakage but much like the rotation system before it these penalties were found to be unnecessary and just hindered the gameplay experience while not adding anything while increasing CPU load.

Here are some early screenshots and info for the buildings related to fluids. Please know that all of these buildings are not using their final assets and their size and appearance will likely change before they are released.

Pipes are built exactly the same as shafts. All of the functionality in building a shaft is also part of building a pipe. I have updated the building hologram for shafts so it now has the proper corner gears and pipes use their own model for straight and corner sections.

For now the only fluid you can gather is water. Unfortunately, with this update there will not be any fluids spawning in the world as that is not a simple thing. Don’t worry there are big plans for a world update happening in the future but more on that on another day.

Water can be collected via the Well which requires a rotation input and produces a small amount of pressure.

When most people think of a pump, is in fact an electric motor and a pump combined together. And the engineer who designed that product matched the motor with the pump based on the specs of each and the desired pressure and flow rate. One of my goals when I was creating Engineer Alpha was to recreate that process of connecting parts together that would work well together. The pump in Engineer Alpha does not just get connected to the electrical grid, it has a rotation input that can be connected to any source of rotational power and the pressure rise scales with the input torque.

The pipe merger can be used to combine up to 3 pipes together into 1. Also the splitter can be used to make a single pipe go into up to 3. Both look like this as of now, marked inputs/outputs coming soon.

Tanks will come in 2 varieties small and large and will be a place to store your excess fluid.

As you may have noticed the Stirling engine from tier 1 could use a replacement when you start getting into iron buildings and parts. The second engine in the game is actually 2 parts the boiler and the steam engine. They are not quite ready to show off yet but I would assume you can guess how they will work for the most part. I will be talking more about these soon, hopefully next week.

This concludes the look at the second type of connector in Engineer Alpha, there is planned to be a third type and you can see a sneak preview of it here.

Sep 26, 2022

Update Build 1.0.0.2 - Partial Update

Project Gunship - Sklor

It has been overwhelming to see the interest and support from everyone for the project since early access release and it continues to provide me with vindication on the work being done.

Jumping into early access, I was motivated to establish an aggressive update schedule and cadence to set users expectations, allow greater transparency in development, as well as to push myself. As we all can relate to the analogy in our lives, when it decides to rain it usually pours, many life events seem to collide consuming much of the anticipated development time. Because of this, I haven't been able to complete everything I wanted to in time for this particular release.

As of now, a partial update has been released granting a tutorial in the training mode. It is pretty barebones and simplistic at this point, but it should give players a better understanding of the HUD elements, as well as how to operate the weapons. I'll revisit this tutorial and make appropriate changes to make it more robust in the next few months.

The other big piece I was hoping to have done by now, is the new game mode that takes infestation to a new level. All this work is in preparation for the upcoming campaign modes as systems are developed to be utilized later; while at the same time, providing more playable content for you. I anticipate this will take another week to be completed. I'll push this release as soon as I possibly can.

Overall, there is still a lot more to be done, but I'll be sure to crank through it as quickly as possible. The feedback I've received has been extremely helpful in making the game better and I encourage everyone to continue reaching out with ideas, issues, and bugs.

Feel free to join our discord (https://discord.gg/rYXRxN2ESu) and communicate with me directly on anything. I think this type of open communication from player to developer is critical in making great games.

As I've mentioned before, I appreciate all your support and will continue to work hard on providing you with the very best. Thanks!

Change log

Added a small tutorial in the training mode that gives a run-down of the HUD and weapons
Added extra weapon details on the HUD (weapon and ammo types displayed for quick reference)
Added +10 AI button in the training mode options
Added additional HUD elements to declare camera lock and weapon misalignment with the camera
Incrementally increased the zoom amount of the camera
Improved the impact dispersion system to display more accurate ranges
Increased the total amount of AI that can spawn during waves in Infestation
Bug fix - Solved issue in infestation when firing weapons between round completion, it'd cause the weapons to continue to fire non-stop
Bug fix - Solve issue causing the aircraft to "miss" its nav target, resulting in it dropping speed to 0

Sep 26, 2022

Abyss Protection Update 1.5b

Abyss Protection - Exbyte Studios

AP 1.5b Update

1) Changes to the balance.

1.5b affects in-game balance a lot. We tried to make the first waves a bit easier, as the monsters were very strong and did not give players a chance.

All changes related to the balance:

Towers

The damage of the defense towers has been changed.
The range and attack speed of the defense towers have been changed.

Monsters of the abyss.

Monsters variation in the waves was rebuilt
HP of monsters were changed.

The speed of world generation has been reduced.

We have changed the generation of the world to balance the forces of both the player and the monsters.

Visual changes

Added shields above the Guards. Now it will be easier for players to visually track where the boss is.

Destroyed structures have been added

If your tower is to be destroyed by a bomber, you can't put a new tower in its tile. You can fix the broken tile by either using a card in the market, or spending 100 coins by clicking on the tile itself.

New types of towers

We are introduced to Mercenaries in 1.5 Patch.

Hire mercenaries for as many waves as you wish, to help fight monsters from the abyss. Mercenaries will appear in the forest and their location can be determined by the indicator.

Bank.

The bank serves as a limiter of the number of accumulated coins. With each new bank built, your limit will increase.

The Royal Mint.

The royal mint produces 25 coins every 10 seconds. Build more mints to improve your defences.

5) Sound processing.

Almost all sounds of defense towers have been redesigned.

The musical theme has been worked out.

Now the soundtrack is variable and will not let you get bored.

6) Key bindings

Added the keybindings tab for binding the necessary keyboard keys.