It's a minecraft mod.
https://www.curseforge.com/minecraft/mc-mods/immersive-portals-mod
- Import the project, enable auto import and let gradle tasks finish
- Download this jar https://github.com/qouteall/ImmersivePortalsMod/blob/master/minecraft-1.14.4-mapped-net.fabricmc.yarn-2.jar and use it to replace C:\Users\username\ .gradle\caches\fabric-loom\minecraft-1.14.4-mapped-net.fabricmc.yarn-2.jar (It contains OptiFine stuff)
- Run
gradlew ideagradlew genSources
A portal entity is one-way and one-faced. A normal nether portal contains 2 portals in overworld and 2 portals in nether.
You can create a portal by command
/summon immersive_portals:portal ~ ~5 ~ {width:4,height:4,axisWX:1,axisWY:0,axisWZ:0,axisHX:0,axisHY:1,axisHZ:0,dimensionTo:-1,destinationX:0,destinationY:129,destinationZ:0}
immersive_portals:monitoring_nether_portal is the portal entity that can disappear when nether portal breaks.
When lighting a nether portal, it will firstly try to link to the obsidian frame with same size and direction in 128 range in the other dimension. You can control the destination of nether portal by building an obsidian frame.
Portal rendering takes place before translucent block rendering. It uses stencil buffer and does not use additional frame buffer when rendering without shaders.
It firstly draw the portal view area. (the view area mesh is not a quad. It's a concave box with 5 faces.)
Drawing view area will increase stencil value by one. Then it will move the player to another dimension, switch objects for rendering and render the world in stencil limitation. It will then render nested portals.
ChunkRenderDispatcher stores an fixed size array of ChunkRenderer s. I changed it into a map.
Client chunk manager uses an fixed size array to store chunks. I changed it into a map.
In server side, it will send redirected packet to players to synchronize world information. If the packet is not redirected, a chunk data packet of nether may be recognized as overworld chunk data in client.
In vanilla if a player is faraway from a chunk, it will be immediately unloaded. But with this mod, it has to wait for 15 seconds to unload.