The UpgradeTreeNodeDef is a fundamental building block in the talent tree system.

It represents individual nodes within a talent tree that players can interact with to gain upgrades and progress through different paths of development.

<Talented.UpgradeTreeNodeDef>
    <defName>NodeIdentifier</defName>
    <type>NodeType</type>
    <upgrades>
        <li>UpgradeDefReference</li>
    </upgrades>
    <sequential>true/false</sequential>
    <connections>
        <li>ConnectedNodeDefName</li>
    </connections>
    <hide>true/false</hide>
    <prerequisitesToShow></prerequisitesToShow>
</Talented.UpgradeTreeNodeDef>

There are three distinct types of nodes in the system:

1. Start Nodes (<type>Start</type>)

   • Represent the entry points of the talent tree
   • Can have multiple start nodes for different starting locations (experimental feature)
   • Must be properly connected to subsequent nodes in the tree

2. Branch Nodes (<type>Branch</type>)

   • Special nodes that define the beginning of new branching paths
   • Hold information about newly formed branches in the talent tree
   • Used to create divergent progression paths

3. Normal Nodes (<type>Normal</type>)

   • Standard nodes that make up the majority of the talent tree
   • Connect to other nodes to form progression paths
   • Not specialized like Start or Branch nodes

The upgrades field contains a list of UpgradeDef references that determine what benefits the player receives when investing talent points in the node:

<upgrades>
    <li>UpgradeDefOne</li>
    <li>UpgradeDefTwo</li>
    <li>UpgradeDefThree</li>
</upgrades>

The sequential field determines how multiple upgrades in a single node are handled:

• Upgrades replace previous ones as the node levels up
• Only one upgrade is active at a time
• Example: Basic → Advanced → Final, where each tier replaces the previous

<upgrades>
    <li>BasicMetabolismUpgrade</li>
    <li>AdvancedMetabolismUpgrade</li>
    <li>FinalMetabolismUpgrade</li>
</upgrades>
<sequential>true</sequential>

• Upgrades stack with each level
• All previous upgrades remain active
• Example: Level 3 would have all three upgrades active simultaneously

<upgrades>
    <li>BasicMetabolismUpgrade</li>
    <li>AdvancedMetabolismUpgrade</li>
    <li>FinalMetabolismUpgrade</li>
</upgrades>
<sequential>false</sequential>

The connections field defines how nodes link together in the talent tree:

<connections>
    <li>NodeDefName1</li>
    <li>NodeDefName2</li>
</connections>

• Each connection represents a possible progression path
• Multiple connections allow for branching paths
• Connections are used for both visual representation and progression logic
• It is very important these connections are set correctly.

Nodes can be hidden or shown based on certain conditions:

<hide>false</hide>
<prerequisitesToShow>
    <!-- Add prerequisites here -->
</prerequisitesToShow>

• The hide field determines if the node is visible by default
• prerequisitesToShow can be used to define conditions for revealing the node

1. Naming Convention

   • Use clear, descriptive defNames
   • Follow a consistent naming pattern for related nodes

2. Tree Structure

   • Ensure all nodes are properly connected
   • Avoid creating isolated nodes or dead ends
   • Test all branching paths for proper progression

3. Upgrade Design

   • Choose sequential vs non-sequential carefully based on intended progression
   • Balance upgrade power levels across different paths
   • Document upgrade effects clearly

4. Performance Considerations

   • Minimize the number of prerequisite checks
   • Keep upgrade lists reasonably sized
   • Consider the impact of many simultaneous non-sequential upgrades