Portable Building Cannon — 1.2

Latest development revision: September 9, 2026

The latest changes are currently marked as unreleased. The build version remains 1.2

New Features

Building Shapes

• Added 15 shapes: Flood Fill, Single Block, Row, Column, Grid, Circle, Sphere, Box, Rock Scatter, Checkerboard, Line, Fill Area, Shapeless Mining, Blast, and Precise Mining.
• Exchange supports compatible shapes, excluding Box and mining shapes.
• Circle, Sphere, and Box support solid and hollow variants.
• Line and Fill Area use two-point selection.
• Flood Fill, Single Block, Row, and Column are unlocked by default. Additional shapes can be purchased.

Upgrade System

• Added five independently upgradeable statistics, each with five purchasable levels.
• Upgrades are purchased using Create Experience Nuggets and saved individually on each cannon.
• Shape unlocks are shared between compatible building modes.

• Intermediate Schematic limits are 128, 256, 512, and 768 blocks.
• Stat upgrades start at 128 nuggets, with a default 77% price increase per level.
• Additional shapes cost 128 nuggets, 256 for Sphere, Box, and Rock Scatter, or 384 for mining shapes.
• Server configuration can disable progression, apply configurable fixed levels, and unlock all shapes.

Schematic & Quill

• Added support for using Schematic & Quill from the cannon’s internal slot.
• Added capture previews and conversion of the selected area into a Schematic stored inside the cannon.

Controls

• Short middle-click: cycle through unlocked shapes.
• Hold middle mouse button: open the radial shape selector.
• H: toggle solid/hollow geometry for supported shapes.
• U: open the upgrade screen.
• X: switch Exchange between matching blocks and all valid exposed blocks.
• Middle-click now controls shapes instead of toggling Exchange scope.

Fuel and Storage Changes

• The internal fuel magazine holds up to 64 items.
• Gunpowder supplies 100 fuel units per item.
• Fire Charges supply 200 fuel units per item.
• Fuel costs use the efficiency multiplier and are rounded per operation.
• External-storage restrictions now apply only to filled Building Packages. Empty packages remain usable in storage inventories and crafting recipes.

Bug Fixes — Latest Revision

• Fixed serialization errors when saving cannons containing more than 20,000 fuel units. Fully upgraded reservoirs now support saving all 28,000 units.
• Fixed the Wand/Exchange action limit incorrectly blocking 768- and 1,024-block Schematics.
• Upgrade payments now count nuggets that can actually be extracted from the same inventory slots used for payment.
• Fixed insufficient accessible funds causing partial payments without granting an upgrade.
• Payments now use the quantity actually extracted, preventing unpaid upgrades when containers refuse or partially fulfill extraction.
• Incomplete payments return the items already withdrawn.
• Schematic and Relocation fuel checks now account for efficiency and per-target rounding.
• Failed placements caused by missing materials now refund the full fuel amount charged.
• Zero-cost actions remain free during preliminary fuel checks.

Building Package Fixes Included in 1.1.5

• Fixed structure data being lost or corrupted during save/load cycles by using vanilla-compatible integer-array storage while retaining support for the previous format.
• Fixed relocated multiblock machines, including Immersive Engineering structures, remaining invisible until a block update.
• Fixed Immersive Engineering multiblocks breaking after rotated placement because their facing was not transformed correctly.
• Preserved Immersive Engineering multiblock data in compact previews of packages containing more than 256 blocks.
• Interrupted or cancelled package launches now return the filled package to the player.
• Small Schematic and Package placement confirmation now checks the targeted or locked anchor, matching the preview’s placement range.

Testing

• Updated the Gunpowder regression test for the 64-item magazine.
• Fixed incomplete test-area preparation that caused intermittent shape-test failures.
• Added regression coverage for nested upgrade payments, failed-placement fuel refunds, upgraded fuel persistence, and 1,024-block Schematic limits.
• All 13 required GameTests passed, including a repeated validation run.
• Build completed successfully, and the release JAR passed the verification script.

Known Issues and Upgrade Notes

• Back up existing worlds before updating. Older cannons still require a defined migration policy for fuel or ammunition exceeding the new base limits.
• Super Glue durability handling in nested containers and component-sensitive material availability still require further work.
• The held-cannon materials HUD has a remaining Schematic-selection issue.
• Efficiency is rounded per operation: a nominal one-unit placement costs two units at level 0 and one unit at subsequent levels.
• Portable Stock Ticker/Schematic Request behavior and optional backpack integrations still require testing in the actual modpack.