Rainfall 1.3.0 — Connected Water

Rainfall now brings growing, connected puddles and terrain-following runoff to Minecraft 1.21.1 on NeoForge.

Water and rain

• Puddles grow and join neighboring water surfaces as rain accumulates.
• Water collects in low spots and flows over lower edges, creating streams along the terrain.
• Walls and raised ground guide the flow; new obstacles stop blocked channels.
• Choose Vanilla or Smooth independently for puddles and streams.
• Animated water surfaces and expanding rings respond to actual raindrop impacts.
• Water uses Minecraft's animated water textures, biome colors, and resource packs.
• Optional Iris support lets shaderpacks treat Rainfall surfaces as water. The final appearance depends on the shaderpack; no specific shaderpack was used for the screenshots.

Engine improvements

• Reused rendering buffers and bounded terrain/path caches reduce repeated allocations and lookups.
• Fair simulation budgets spread work across active chunks and limit work per update.
• Water exchange conserves the existing water amount instead of creating extra water while spreading.

Settings and compatibility

Press K, or run /rainfallclient settings, to change water styles, animation, rings, and quality settings.

Minecraft 1.21.1 · NeoForge · Client-side · Beta

This remains a shallow visual water simulation. It does not place vanilla water blocks. Dense water scenes and higher detail settings can still add rendering cost.

Validation

• Java 21 build completed successfully.
• All 42 automated tests passed.
• Tested in Minecraft with connected puddles, slopes, obstacles, streams, and actual drop-impact rings.

Screenshots are new, unedited in-game captures with Smooth puddles and streams and vanilla rendering.