The Powder Toy news & patch notes

Version 99.4 (build 393) 2026-04-01:

After a painfully long wait, the new TPT version has arrived! The game seems to have been abandoned for so long, that it's in a bit of a ... mess. The element labels have all worn off with time. We hope you'll be able to sort it out

- Fix gravity leaking through gravity wall for a frame when undoing - Fix infinite pressure / velocity bug in the bottom right corner - Fix missing elements and spurious warning in certain saves made between versions 78.1 and 96.0 - Cap VIBR .tmp and explosion .temp - Fix prop sampling ignoring temperature scale - Fix !set commands defaulting to Kelvin, instead of to current temperature scale - Fix possible game crash when using invalid coordinates in !bubble - Fix rx/ry arguments to sim.toolBox - Fix compatibility sim.TOOL_* constants - Make gravity mask accessible from Lua - Fixed a typo in the rules (via ClayStan404 #994) Since there were so many bugfixes this month, we decided to do another minor release. Some of the bugs are very old, like gravity wall leaks while undoing, or an infinite pressure bug in the corner. Others are new, like elements being missing in certain older saves.

- Fix update check not processing when simulation is paused or when manually triggered - Fix PIPE rendering garbage data as elements when carrying PIPE with PIPE - Stop displaying 0 FPS when the sim is paused - Fix an issue where fire effects rapidly jump to their end results in high refresh rate monitors, when pausing - Fix some UI animations running faster in high refresh rate monitors This is a small update to fix bugs from version 99.1. It brings the fps display back in line with how it was before, and fixes some other bugs on high refresh rate monitors

Version 99.1 - 2025-01-25 Allow disabling the automatic update check at startup Add DEBUG_AIRVEL for drawing lines showing air velocity at the cursor's position FPS cap now only applies during main sim and not other interfaces Make ambient heat drag effects weaker Give visual indication of vote/fav requests being in progress Fix some particles flickering when SRT is enabled Fix occasional crash involving overflowing menu sections Fix crash on exit while there are Lua components visible Fix photons sometimes being created with weird colors Fix "far away" air heat and velocity code working correctly only in one direction Prevent heat convection in liquids looking farther than 1px away Fix LITH breaking temperature limits Fix custom elements not showing up when loading saves via ptsave: links This is a minor version that fixes a lot of bugs and leftover issues from 99.0, including some crashes and issues with SRT (Separate Rendering Thread). It also fixes some old Simulation oddities. The FPS cap now only applies to the main window as well, no more rapidly spinning spinners and janky scrolling when you turn off the FPS cap.

You wake up in the morning, and rush downstairs to your tree. Instead of wrapped presents, you find GLAS containers. What is this? DUST? WATeR? PLUTonium? And a stocking full of COAL? That's right, it's a new version of The Powder Toy, just in time for the holidays. This version adds some new options to the save browser to improve searching, and puts rendering into a separate thread, which can really boost the framerate in certain scenarios with fancy effects on. There's also now in-game credits, a new tools api for creating Lua tools, and various simulation / crash fixes. Full changelog below: - Add an option to render the simulation on a separate thread. This may increase framerate when fancy effects are in use - Add day/week/month/year selector in the search - Add documentation on new advanced search (press F1 in save browser) - Add credits UI (accessible from options menu) - RSST/RSSS now sets its .tmp from the .ctype of nearby BCLN/PBCN - Add !get console command - Improve heat convection in ambient heat - FIRE from HYGN+OXYG now creates WTRV, not DSTW (via jm211-tpt #979) - STOR can absorb radiation particles (via jm211-tpt #978) - Make BGLA PROP_DEADLY (via ChromicQuanta #964) - Add CtypeDraw for VOID / PVOD (via Onestay42 #953) - Make paste previews follow the current renderer settings - Clicking "Submit" comment with an empty textbox reloads comments - Show placeholder text in text fields even when focused - Don't complain about missing elements that aren't actually used - Ctrl+q - don't trigger quit dialog if alt is also held - Make global quit shortcut optional - Fix RSST/RSSS not respecting the CarriesCtypeIn field - Reset GEL's tmp field when it turns into RSST - Fix saves that abuse extreme spark effects to lag the game - Fix chance of NEUT spawning PHOT in GLAS and of PHOT multiplying in GLOW - Reaction bounds fixing for EMP and VIBR (via jm211-tpt #980) - CRMC low pressure - preserve .temp when breaking - Fix unnatural stacking near powers of 2 positions - Fix stamp browser refusing to show stamps sometimes - Stop scrolling in ScrollPanels on mousedown - Fix result of "Large Screen" dialog on first launch being ignored, causing scale to reset back to 1 on the second launch - Fix automatic HiDPI scaling, TPT is now in full control of its own scale (via dxgldotorg #956) - Fix crash when drag-and-dropping drives from My Computer into TPT - Fix crash involving invalid SOAP properties - Fix crash when navigating away from a save while voting on it - Implement Lua tools (tools. api) - Add sim.listDefaultGol - Expose sim.canMove constants - New property PROP_PHOTPASS that allows PHOT to pass through an element - Fix gfx.drawPixel being unable to draw in event.AFTERSIMDRAW - Fix NUM_PARTS being wrong almost all the time - Track custom elements inside SNOW/ICE ctype when saving - Remove CRACKER and CRACKER2 menusections

Today marks an important milestone - TPT is now playable through Steam! We've dreamed of this for years, but it was always so elusive. Thanks to the efforts of Sylvi and the rest of the TPT staff we finally made it a reality. The steam release supports all major platforms on PC, and should even run on steam deck! Launching through steam gives you Steam Overlay support, and your local saves are synced via Steam Cloud. Otherwise, it's exactly the same game you know and expect. TPT is and will always remain free. We will still distribute it on our website, but we hope also having Steam download links can help grow our community. TPT has been an open source game since 2010, meaning it's developed by the community and will never have any DRM or other restrictions on it. Discuss the game in the Steam community, or on our forums Information on elements, guides, and scripting / modding documentation is available on the wiki TPT is Open source. Contribute to its development on GitHub