ACAR Miscalculates Victory With Complex Force Layouts

by Alex Johnson 54 views

Introduction

In this article, we delve into a peculiar issue encountered within the MegaMek/MekHQ environment, specifically concerning the Automated Combat Analysis Report (ACAR). The ACAR system appears to struggle with accurately assessing the chances of victory when dealing with complex force layouts, particularly those involving parent forces and child forces within a combat team. This can lead to significant discrepancies in the reported probabilities, potentially affecting strategic decision-making during gameplay. The problem manifests when a combat team contains units both in the primary force and in a subordinate force. In such cases, ACAR seemingly fails to account for all units, leading to an underestimation of the team's combat effectiveness. This issue was observed in a scenario involving a complex team structure and was further investigated using different savegame configurations to highlight the inconsistencies in ACAR's calculations. This article aims to provide a comprehensive understanding of the issue, including steps to reproduce it, attached files for further analysis, and relevant version information for the software in question. Understanding these nuances is crucial for players seeking to leverage ACAR effectively in their MegaMek/MekHQ campaigns.

Problem Description

The core issue lies in how ACAR interprets and calculates combat probabilities when a combat team's composition is spread across both a parent force and a child force. Instead of aggregating the strength of all units within the team, ACAR seems to overlook some units present in the child force. This results in a lower overall assessment of the combat team's capabilities, leading to a significantly reduced probability of victory being reported. For instance, in the specific example provided, a combat team with units distributed between a parent and child force was perceived by ACAR as having a very low chance of success. However, when the same units were reorganized into a single-level combat team structure, ACAR's assessment drastically changed, indicating a 100% chance of victory. This stark contrast underscores the inconsistency in ACAR's calculations and highlights the potential for misrepresentation of combat readiness. The attached image further illustrates the complexity of the team structure that triggered the issue, providing a visual reference for understanding the arrangement of units within the parent and child forces. This problem can be particularly misleading for players who rely on ACAR to gauge their combat effectiveness and make informed decisions about troop deployment and engagement strategies. It's essential to recognize this limitation when using ACAR in scenarios involving intricate force hierarchies.

Steps to Reproduce

To replicate this issue, follow these steps:

  1. Load the provided savegames into MekHQ.
  2. Examine the combat team force layouts in each savegame.
  3. In the first savegame ("layered combat team"), observe the sub-force structure within the combat team.
  4. Run ACAR on this combat team and note the reported chance of victory.
  5. In the second savegame ("flat combat team"), observe that all units are in the same-level combat team.
  6. Run ACAR on this combat team and note the reported chance of victory.
  7. Compare the ACAR results between the two savegames. You should observe a significant difference in the reported chances of victory, despite the same units being present in both scenarios.

Attached Files

These files provide concrete examples that demonstrate the issue and allow developers and users to further investigate the problem. The savegames represent the same game state with only the combat team force layouts differing, making it easy to compare ACAR's assessments under different organizational structures. The customs.zip file contains any custom units or configurations used in the savegames, ensuring that the issue can be reproduced accurately across different environments. By examining these files and following the steps outlined above, you can directly observe the discrepancy in ACAR's calculations and gain a better understanding of the conditions under which this issue arises. This hands-on approach is invaluable for both confirming the bug and for developing potential solutions or workarounds.

Severity

The severity of this issue is classified as Medium (Gameplay Limitation). While the core functionality of MekHQ remains operational, the impaired accuracy of ACAR can lead to suboptimal gameplay experiences. Players relying on ACAR for strategic decision-making may be misled by the inaccurate victory chance assessments, potentially resulting in poor tactical choices and unfavorable outcomes in battles. Although the game is still playable, this limitation affects a non-core functionality that provides valuable insights and guidance to players. The inaccurate reporting can undermine the trust in ACAR as a reliable tool for evaluating combat readiness, forcing players to rely more on manual assessments and intuition. This can be particularly problematic for new players or those unfamiliar with the intricacies of force composition and combat dynamics. Therefore, while the game is not broken, the impaired functionality of ACAR significantly diminishes the overall user experience and introduces a degree of uncertainty in strategic planning. Addressing this issue would greatly enhance the reliability and usefulness of ACAR, making it a more valuable asset for players in MegaMek/MekHQ.

Environment Details

  • MekHQ Suite Version: 0.50.10-nightly-2025-11-11
  • Operating System: Windows 10
  • Java Version:
Java Vendor: Eclipse Adoptium     Java Version: 17.0.15

These details are crucial for identifying the specific environment in which the issue was observed. The MekHQ Suite version pinpoints the exact build of the software being used, allowing developers to trace the codebase and identify any potential bugs or regressions introduced in that version. The operating system provides context for the platform on which the software is running, as certain issues may be specific to particular operating systems or configurations. The Java version is particularly important, as MegaMek/MekHQ is a Java-based application, and compatibility issues or bugs in the Java Runtime Environment (JRE) can sometimes affect its behavior. In this case, the Java version is Eclipse Adoptium 17.0.15, which is a widely used and supported distribution of Java. Having this information readily available helps developers to reproduce the issue in a similar environment and to ensure that any fixes or patches are compatible with the specified Java version.

Verification

  • [x] I confirm this is a single, unique issue that hasn't been reported before
  • [x] I have filled and provided all necessary information above
  • [x] I have included any and all logs, custom units, and CPNX (save) files
  • [x] I have asked on MegaMek Discord about this issue
  • [x] I have confirmed this issue is being opened on the correct repository: MegaMek, MegaMekLab, or MekHQ

These confirmations serve as a checklist to ensure that the issue has been thoroughly investigated and documented before being reported. By verifying that the issue is unique, the reporter avoids duplicating existing bug reports and wasting developers' time. Providing all necessary information ensures that developers have sufficient context to understand and reproduce the issue. Including logs, custom units, and save files allows developers to examine the specific conditions under which the issue occurs. Asking on MegaMek Discord helps to gather input from other users and potentially identify workarounds or alternative solutions. Finally, confirming that the issue is being reported to the correct repository ensures that it reaches the appropriate development team for resolution. These steps collectively contribute to a more efficient and effective bug reporting process, increasing the likelihood that the issue will be addressed promptly and thoroughly.

Conclusion

In conclusion, the ACAR system in MekHQ exhibits a notable flaw when assessing combat teams with hierarchical force layouts. This issue leads to inaccurate victory chance predictions, potentially impacting strategic decision-making during gameplay. By providing detailed steps to reproduce the problem, along with relevant savegames and environmental information, we hope to facilitate a swift resolution. Addressing this limitation would significantly enhance the reliability and usefulness of ACAR, benefiting the MegaMek/MekHQ community. For further information on MegaMek, you can visit the official MegaMek website.