Scalar Evolution

Scalar Evolution is a Minecraft mod about computer technology and electronics. Each placeable computer block runs its own real Linux on an emulated RISC-V CPU; framebuffers stream to clients as H.264, audio as Opus, terminal blocks render through a JNI port of mlterm for full xterm-class VT fidelity (Sixel, ReGIS, the lot).

This is the 1.21.1 / NeoForge continuation of LekKit's original (Minecraft 1.7.10), maintained jointly by @pufit and @SolAstrius.

The underlying VM is RVVM, also by LekKit, used here through pufit's fork which carries the JNI bridge and a handful of patches the mod depends on.

Alpha quality — hic sunt dracones.

Why the Fork?

LekKit's Scalar Evolution targets Minecraft 1.7.10 and hadn't been brought forward. We didn't fork because of any disagreement — pufit started the port to bring it to a current Minecraft, and Sol joined for co-development.

In practice "port" undersells it. The only code carried verbatim from upstream is the lekkit.rvvm.* JNI binding package (~30 files, ~280 LOC) that talks to RVVM. The Minecraft side — blocks, block entities, menus, screens, network, recipes, datagen, rendering, peripheral bus, componentry, codecs, machine integration — is a from-scratch Kotlin reimplementation of roughly 31k LOC across 270+ files. The mod's conceptual DNA (in-world emulated computers, real guest Linux, customisable hardware, persistence) is LekKit's; the actual shipping codebase is overwhelmingly new.

What's in it today

Emulation core

• Real RISC-V Linux per computer. Buildroot or Alpine boots inside RVVM; persistent disks travel with NVMe items between cases. Disk images are GC'd when no longer referenced.
• CPU tier 1 / 2 / 4 hart progression with branded part names; SoC items expose tier as part of their type.
• RAM tier 5 at the top end of the memory ladder.
• Audio sync — guest audio is anchored to a PTS wall-clock so aplay doesn't drift against the framebuffer over long sessions.

Display & terminals

• VT100 / VT220 / VT340 / VT420 / VT520 terminal blocks driven by a JNI port of mlterm (mlterm-fb-embed). Full xterm-class fidelity: ReGIS and Sixel both render. Period-correct BootRom Setup pages (SET-UP A / B / CRT FX / MOD) on F3.
• CRT FX shader with scanlines, phosphor bloom, chroma shift, vignette, and slight curvature on the in-world block face.
• Framebuffer streaming as H.264 via a vendored OpenH264 build (libscev_h264, cross-built with zig cc).

Audio

• Sound card end-to-end: HDA → Opus → OpenAL. Guest aplay reaches every nearby player through the Minecraft network layer with per-listener spatialisation.

Peripherals & I/O

• Peripheral bus with a typed component API; compat modules can declare components against the upcoming /sys/scev/ filesystem via annotation + DSL.
• GPIO, I²C, and an MCU board for tiny SoC + flash workflows. Bare-metal blinky firmware (RISC-V assembly) ships as the hello-world recipe.
• CC: Tweaked integration, scev-as-computer: the guest Linux can enumerate, introspect, and call CC peripherals over /dev/ttyS1 — including peripherals attached through wired modems.

In-world progression

• Processing-machine chain for paper / ink / ribbon production feeding a teletype that prints the kernel console as it boots.
• Sectioned creative tab with computing / motherboards / storage / expansion / cases & peripherals / crafting buckets.

Client & integration

• owo-ui screens for the computer case, motherboard, and other configurators.
• Jade HUD providers for at-a-glance machine state without opening the GUI.
• Zig guest agent (tools/scev-guest-zig/) — a small RISC-V Linux userland that speaks RPC over a serial port for host↔guest introspection and orchestration.

Building

./gradlew build

The build clones pufit/RVVM and the mlterm-fb-embed fork, compiles librvvm, libscev_h264, and libscev_term for the host platform via zig cc, fetches a sys-install Alpine image from scev-alpine's rolling release, and ships everything inside the mod jar.

If you want to help

• File issues at SolAstrius/ScalarEvolution2/issues.
• Models and textures could use love. Open a PR; be aware that proposals might be rejected on art-direction grounds.
• The peripheral / component API is open for compat modules — the lekkit.scev.component package documents the annotation + DSL for declaring components against the upcoming /sys/scev/ filesystem.
• Consider contributing to RVVM or [pufit's fork].

Platform

• Minecraft 1.21.1
• NeoForge 21.1.226+
• Java 21

License

LGPL-3.0-or-later, matching upstream.