The new 4JLibs CaptureThumbnail produces all-black 64x64 PNGs because
its internal m_backBufferTexture copy fails silently. Bypass it entirely
and capture from the swap chain backbuffer using the same proven approach
as our F2 screenshot, with center-crop and downsample to 64x64 PNG.
Includes fixes and some modernizations compared to the original 4J
library binaries. Also introduces functionality to support stuff like
F2 screenshots, etc. This is basically the beginning of modernizing the
codebase.
Add version string (branch/version) to the debug overlay when F3 is active.
Also add a new keyboard shortcut (B key while F3 is held) to copy the
version string to the clipboard and show a confirmation message. This
improves debugging and support by making version information easily
accessible.
Before this change, turning VSync off did not actually uncap your frame rate. The game ran in borderless fullscreen, where Windows' desktop compositor owns the display pipeline and applies its own VSync regardless of what the game asks for. So on a 240Hz monitor with a GPU that could draw 800fps, you still only saw 240 frames per second and the other 560 were thrown away. Worse, the frames you did see were up to a refresh cycle stale by the time they hit your eyes, which is input latency you can feel when moving the camera or aiming.
Fullscreen now uses true DXGI exclusive mode, where the compositor is out of the way and the swap chain writes directly to the display. Every frame the GPU produces lands on screen as soon as it is ready, so "VSync off" actually does something. Expect FPS to climb well past your monitor's refresh rate and the mouse to feel noticeably more responsive.
Exclusive fullscreen also displays at your monitor's native resolution with no driver-side scaling or filtering. The backbuffer is grown to match the monitor exactly before the transition, and the display mode is pinned to the backbuffer size so nothing in the output pipeline resamples your pixels on the way to the screen. The result is a crisp 1:1 image with none of the softening or greyish filter that stretched output can introduce.
Yes, this is the mode where screen tearing can happen. Tearing gets a bad reputation but it is a visual tradeoff, not a bug, and many players prefer it over the latency VSync causes. If you want to avoid tearing, just turn VSync on in the settings and the game will cap cleanly to your refresh rate. You now have a real choice between the two instead of "off" quietly being broken.
Under the hood, F11 and the saved fullscreen preference both route through a new ApplyExclusiveFullscreen path that does Microsoft's recommended transition: grow the window to cover the monitor, ResizeTarget with no scaling so the display mode is pinned to the backbuffer size, SetFullscreenState(TRUE), SetColorSpace1(sRGB), then a second ResizeTarget so picky drivers actually apply the mode. Exit forces a real decorated windowed state so F11 cycles cleanly between windowed and exclusive fullscreen. ResizeD3D skips its swap-chain-recreate path while in exclusive mode so it does not fight DXGI for ownership.
The swap chain's RefreshRate changes from a hardcoded 60Hz to 0/0 so DXGI matches the current display mode. Fixes an "input signal out of range" error that could happen on high-refresh monitors after entering fullscreen, where the monitor was being asked to renegotiate timing off of 240Hz down to 60Hz on every launch.
The previous FLIP_DISCARD swap chain configuration was producing broken rendering and a stretched aspect ratio on startup and after window resize, because the closed-source 4J Renderer library holds hidden backbuffer references that prevent ResizeBuffers from succeeding in flip mode. Switches the swap chain to the legacy bitblt DISCARD model with BufferCount=1, which lets the "destroy old, create new" resize path in ResizeD3D work cleanly. In-world rendering and aspect ratio are now correct at launch and across window resizes.
Known regression from this change: screen tearing no longer works when VSync is off. On Windows 10 and 11, bitblt swap chains always go through the DWM compositor, which locks presentation to the monitor refresh rate regardless of the SyncInterval parameter we pass to Present. Every frame the renderer produces above the refresh rate is silently dropped by DWM, which hurts input latency compared to a true uncapped-fps presentation path. The next iteration will reverse-engineer the 4J Renderer struct layout to find where those hidden backbuffer references are stored, release them before ResizeBuffers, and switch back to FLIP_DISCARD with ALLOW_TEARING so real tearing is possible again.
Also removes the dead SwapChainVSyncProxy COM wrapper. The proxy was originally intended to intercept Present calls from the Renderer library for VSync control, but the library hardcodes SyncInterval=1 and does not dispatch Present through the proxy vtable, so it was never actually doing anything useful.
Matches the packet size limit used by the plugin-api fork. Our 512KB
limit caused "Connection lost" when their server sent large packets
(e.g. chunk data) that exceeded our cap.
Implement Book & Quill:
- IUIScene_WritingBookMenu and UIScene_BookAndQuillMenu for UI
- Edited UIControl_Label to add direct editing (quite hardcoded to my needs right now)
- Reimplement scrapped custom payload packets for books and signing
- Other misc changes
TODO:
- Coloured and scambled text
- Book copying
- Clean up code
Bypass the 4J RenderManager's hardcoded SyncInterval=1 by calling
the DXGI swap chain directly with Present(0, ALLOW_TEARING) when
VSync is disabled. Falls back to the library's Present on failure.
Relocate VSync/Fullscreen setting flags from bits 18-19 to bits 24-25
to eliminate overlap with the render distance byte (bits 16-23).
Sync the Fullscreen game setting when F11 is pressed so the graphics
menu checkbox stays accurate.
Remove tracked DumpSwf.class (already covered by tools/*.class gitignore).
Move screenshot capture from Minecraft::tick() (which requires an
active player) to the Windows64 main loop alongside other global
key handlers (F1/F3/F11). F2 now works from the main menu, pause
menu, settings, inventory, crafting, and all other screens. Chat
message still shown when in-game.
Replace the XOR obfuscation cipher with AES-128-CTR using the Windows
BCrypt API. Key material grows from 16 to 32 bytes (16 AES key + 16 IV).
All callers auto-adjust via StreamCipher::KEY_SIZE. No handshake or
protocol changes needed beyond the larger MC|CKey payload.
Comprehensive security system to protect against packet-sniffing attacks,
XUID harvesting, privilege escalation, bot flooding, and XUID impersonation.
- Stream cipher: per-session XOR cipher with 4-message handshake via
CustomPayloadPacket (MC|CKey, MC|CAck, MC|COn). Negotiated per-connection,
backwards compatible (old clients/servers fall back to plaintext).
- Security gate: buffers all game data until cipher handshake completes,
preventing unsecured clients from receiving any XUIDs or game state.
- Cipher handshake enforcer: kicks clients that don't complete the handshake
within 5 seconds (configurable via require-secure-client).
- Identity tokens: persistent per-XUID tokens in identity-tokens.json,
issued over the encrypted channel, verified on reconnect. Prevents XUID
replay attacks. Client stores server-specific tokens.
- PROXY protocol v1: parses real client IPs from playit.gg tunnel headers
so rate limiting, IP bans, and XUID spoof detection work per-player.
- Rate limiting: per-IP sliding window (default 5 connections/30s) with
pending connection cap (default 10).
- Privilege hardening: OP requires ops.json, live checks on every command
and privilege packet. Host-only server settings changes.
- XUID stripping: PreLoginPacket response sends INVALID_XUID placeholders.
- Packet validation: readUtf global string cap, reduced max packet size,
stream desync protection on oversized strings.
- OpManager: persistent ops.json with XUID-based OP list.
- Whitelist improvements: whitelist add accepts player names with ambiguity
detection, XUID cache from login attempts.
- revoketoken command: revoke identity tokens for players who lost theirs.
- server.log: persistent log file written alongside console output with
flush-per-write to survive crashes.
- CLI security logging: consolidated per-join security summary with cipher
status, token status, XUID, and real IP. Security warnings for kicks,
spoofing, and unauthorized commands.
Resolve _minecraft._tcp.<hostname> SRV records before connecting,
matching Java Edition behavior. Players can connect using just a domain
name and the client will look up the actual server address and port
from DNS. Falls back to the original hostname/port if no SRV record
exists or the address is a numeric IP.
Replace the boolean-flag-based async join system with a clean state machine
(eJoinState enum) and move connection progress handling from UIScene_JoinMenu
into UIScene_ConnectingProgress as a dedicated UI class.
Combines the best of two approaches: non-blocking sockets with select()
timeout and SO_RCVTIMEO clearing (prevents random disconnects) with the
upstream's state enum, FinalizeJoin separation, and ConnectingProgress UI.
JoinGame() now returns JOINGAME_PENDING on Win64, and
PlatformNetworkManagerStub::DoWork() polls the join state to finalize
the connection when the background thread succeeds.
Loki Rautio
piebot