Developed by G3P with Unreal Engine 5, using art assets from the Unreal Marketplace. Styled using the Gamemakin UE5 Style Guide
Every NPC in the game is controlled by their own behavior tree and has an assigned home building and a workplace building. Each NPC tries to find, reserve, navigate to, and work on their own tasks from a list of available tasks around them filtered by rules defined by their workplace.
This system is core to the balancing of the game. Each NPC belongs to a house and each house has a limited number of attachable NPCs. There is also a limited number of houses and thus a limited amount of workers. House will be upgradable at the expense of resources, and the requirements will be more and more demanding/rare as the game progress.
NPCs handle:
- Building of game objects
- Harvesting of mature crops
- Picking fruit from trees
- Watering of crops
This system is a personal trial of implementing complex AI systems in factory management games. Although it is not as efficient in finding and operating non-random farm tasks compared to centrally controlled AI traditionally used in management games, this system offers great scalability, modularity and customizability since all action definitions are individually separated in each behavior (work/task) and available behaviors for each worker are filtered by each workplace's rules. This creates a boilerplate system that enables mod creators to extend the AI system easily.
- The task management system in-game uses one of Unreal Engine 5's newest features in beta testing - "Smart Objects"
- An actor that contains a Smart Object component is spawned by Game Objects like farm tiles with matured crops. The Smart Object component contains a Smart Object Definition that contains a Gameplay Behavior Config which contains a Gameplay Behavior Class that offers tasks and can be discovered by AI agents based on their workplace's given filters (e.g. agents working at a farm building can execute behaviors (work/task) that involve a nearby farm tile)
- Available agents scan around them with a filter provided by their workplace and locate a random but closer object, and tries to reserve the slot. A slot can be claimed by multiple agents but only one reservation will be valid
- If the reservation succeeded, the AI agent will navigate to the slot and get information from the Smart Object about how to operate it ("behavior")
- After the AI agent completed the behavior, or during the behavior when a notify completes the behavior early, additional code is triggered to make changes to the world as a result of the "behavior" of the AI agent
- After a successful task search and completion, the AI agent searches again in 2 seconds to allow animations to complete etc. If the task searching or completion failed, the AI agent waits for 5 seconds to start another round of searching, to reduce the average performance impact of the search
- Place down objects in grid cells
- Object will occupy cell preventing another placement
- Temporary: Select objects/crops to place with 1-9 keys
- Show placement preview in placement mode
- Hints if placement is valid/invalid
- When planting crops, preview shows coresponding crop products instead of planted crops
- Placement verification different for different Game Object types
- Placement preview accuratly show validity and position
- Hover mouse over a placed object to highlight it
- WIP: showing corresponding stats
- Click a placed object to select (different highlight) it, click again to unselect
- Press backspace to delete selected objects
- WIP: showing available actions
- Line trace for placement target each tick if in placement mode
- No actions if no change in calculated grid position
- Grid Manager contains array of
generated grid cell actorsGame Objects which index is the grid coordinates, Grid Count per row/column, and Cell Width - Grid Manager also acts like a function library for functions like getting closest Grid Cell position or converting grid coordinates to world coordinates
Each Grid Cell keeps:Whether it is occupiedLinked Game Object type enumLinked Game Object referenceNeighboring Grid Cell referencesGrid Cell X and Y coordinates
- Each Game Object keeps:
Linked Grid Cell reference- Game Object type enum
- Sizes in each direction
- Grid Coordinates
Clickable component for Game Objects, if added, manage mouse hover and click(migrated to Game Object Base)In Placement component for Game Objects, added to object placement previews, validifies object placement based on selected object/crop, changes mesh materials to hint valid/invalid placements(migrated to Player Controller)
- Place down crops on farm tile objects
- Can only plant on empty farm tiles
- Dictinct types of crops has:
- Customizable number of stages
- Different mature time requirement
- Auto-calculated required time for each stage
- Randomized growth rates
- Individual plants generated with random position, scale, and rotation to reduce repetitiveness
- Plants moves with wind
- Show planting preview of each plants
- Crop Manager keeps array of currently occupied farm tiles
- Increments groth progress randomly each second, notify the farm tiles to update crop meshes as groth process increases
- Crop details stored in customizable data table, adding a crop variant is less than 1 minutes of work
- Used animated material based on render position and time to calculate transforms for vertex positions
- Very easy-to-expand datatable for introducing new types of plants or altering plant properties
- Included fields are:
- crop name
- number of growth stages
- meshes for each growth stage
- maximum "matureness"
(Crop Manager increment similar amount for each crop types, but each crop type have different max matureness causing them to mature quicker/slower and have shorter/longer stages if they have the same stage count)
- Included fields are:
- Save current game
- Grid properties
- Basic Game Objects
- Planted Crops and Crop growth
- NPC locations and linked building coordinates
- Player transformations
- Automatically load saved game
- Deleating saved game
- WIP: Save games to different slots
- Restart level with saved game
- Data being saved:
- Grid width and Cell width for Grid population
- Array of Placed Game Objects
- Game Object Class
- Linked Grid Cell's X and Y coordinates
- Array of placed crops
- Crop Type Enum
- Current Matureness
- Linked Grid Cell's X and Y coordinates
- Player transformation - not including zoom level etc., yet
- When repopulating world:
- Spawn Grid Manager
- Re-create Grid and neighbor connections based on stored values
- Spawn Crop Manager
- Re-spawn new Game Objects with Grid Cell's transformation
- Re-plant crops and grow to recorded matureness, manager registration and stages calculation done by same function
- Re-apply player transforms
- Start Crop Manager growth
- Each crop plant's random transformation will be regenerated randomly
- Save file versioning for forward-compatibility
- Move camera with WASD
- Orbit and Pitch camera with QE, RF, and mouse right drag
- Zoom in with Left Shift, zoom out with Space
- Dynamic move speed based on zoom level