NoCubes is a mod by Cadiboo for 1.12.2+ that creates smooth terrain in Minecraft. It is the spiritual successor of the NoCubes mod by Click_Me for 1.7.10.
No Cubes Reloaded is a mod made by FellFromTheSky and LeBossMax2 that is another way to create smooth blocks in Minecraft.

Important: Read BEFORE you download!

• NoCubes is currently under development. It is not fully stable or completely finished.
• Bug reports/Issues should go on GitHub or in the appropriate channel on the discord server.
• Visit the official website of NoCubes here and join the discord for pre-releases, development updates and much, much more!
• No Cubes Reloaded is pretty stable if configured correctly.

Thats all the super-important stuff, feel free to download and play the mod now. Enjoy!

About NoCubes and NoCubes Reloaded:

NoCubes and NoCubes Reloaded are NOT the exact same mod. They are developed by different authors. NoCubes is aimed at a more photorealistic and survival-playable experience that continues the trend of NoCubes 1.0 while NoCubes Reloaded aims more at re-creating the original 0.8 NoCubes experience with a slightly less smooth and more video-game type feel. Both mods currently have their home on this single page though. Read more about NoCubesReloaded here.

About NoCubes

No Cubes is a completely unique mod that aims to add an exceptional twist to normal Minecraft gameplay and is the first mod in Minecraft history to fully transform and improve Minecraft’s terrain. NoCubes drastically transforms Minecraft’s traditional blocky terrain into smooth, rolling landscapes complete with circular caves, flowing mountain ranges and jaw-droppingly realistic scenery while leaving your painstakingly curated buildings untouched.

The mod is entirety multiplayer compatible, so you can adventure and enjoy the experience of re-exploring all that Minecraft’s abundant landscape has to offer in the company of your friends. Furthermore, the mod has an endless range of customisable options that the player can tweak to their hearts content in order to achieve the perfect experience. Additionally, NoCubes has built-in compatibility with other mods, most notably BetterFoliage, OptiFine, Dynamic Lights and Shaders so that you can view Minecraft in its full glory.

NoCubes is exceptional for a number of reasons. Firstly, it does all its modifications without affecting your FPS at all. It is also so optimised that, when used on certain configurations, it is faster than Vanilla’s rendering system. Finally, it functions in a way that doesn’t actually modify the way the game works. Blocks, while their appearance and collisions may have been changed, are still square at heart. The mod merely makes the existing cubes have more polygons in a way that makes sense for their environment.

At first glance the world may seem to have been drastically changed, but this strange new world actually feels quite similar once you explore it for a little bit. After traveling around your world for a while, you will realise that the vista you are inside is still the same familiar landscape you know and love. And, though the ground is smoother and the trees are round; the magical and unique way the world unfolds, generates and interacts with you hasn’t changed.

The latest update to the mod features new renderers - such as OldNoCubes and SurfaceNets - to better suit individual players preferences, smooth lighting, liquid bodies that reach all the way to the shoreline, accurate collisions, rounded trees, smooth biome color transitions, enchanted multiplayer capabilities, many performance improvements and speed upgrades, RAM optimisations, texture randomisation, particle integration, leaves separation, faster lighting, texture improvement, emissive lighting support, increased mod compatibility and a multitude of other user-customisable options.

This isn’t all that this mod has in store though, with even more mod compatibility, texture blending, even more performance optimisations, tree branch and trunk tweaks, placement previews, 3d minimaps, community configuration presets, higher resolution renders, more translations and more renderers all being worked on, and scheduled to be added in an upcoming update.

Bonus Features in NoCubes

This mod includes fixes for a number of vanilla fluid rendering bugs. These fixes are enabled separately from the main mod, so you can play without smooth terrain and only the improved fluid rendering. These features include Smooth Fluid Lighting, Smooth Fluid Biome Color Blending and Natural Fluid Textures.

About No Cubes Reloaded

NoCubes is currently being ported to 1.15.2 and will be merged with the No Cubes Reloaded project by FellFromTheSky and LeBossMax2. More info on the discord server.
Any changes made to No Cubes Reloaded requires a lot of time and effort. So please be patient and comprehensive.

NEVER USE NO CUBES RELOADED WITH NO CUBES INSTALLED.

How to configure No Cubes Reloaded TO AVOID RENDERING BUGS

To ge best results with shaders and / or parralax occlusion mapping or if you get void lines between blocks or bizarre snow :
1- Stop the game
2- Open nocubesreloaded-client.toml config file.
3- Find the line named texture_mode.
4- Use FULL_TEXTURE option instead of the default option, especially if you're using shaders.
5- Restart the game, and you're ready to go.
THEN, IF YOU'RE USING OPTINE
- DISABLE BETTER GRASS
- (OPTIONAL) DISABLE CONNECTED TEXTURES.

FEATURES :

- An entirely alternative rendering model.
- No Core mod dependency
- Natively compatible with Optifine and other mods that use core mods (because of the lack of coremod).
- Better management of lighting/brightness and shadows.
- Custom model shape for leaves and snow.
- Better smooth models for the smooth blocks that touch fully cubical vanilla blocks.
- Better smooth models for the smooth blocks that touch non fully cubical vanilla blocks (example : flowers, grass, tall grass, fern, ...).
- Fixing the lighting and shadows of the models according to them x,y,z pos and angle of the facings and the lighting sources (sun torches).

BUGS TO FIX :

Going too far in the world makes certains blocks textures render as "ghost". See it here.
It can be fixed by reloading the world, which means disconnecting and reconecting to it.
Some entities, like skeleton, are not able to move on any smooth blocks. It definitly needs to be fixed.
Those bugs can't actually be fixed.

TO DO :

- Fix bugs.
- Make the smooth leaves more smart*.
* This means that leaves follow the pattern of the tree, so the leaves of two different trees not touch themselves.
- Smooth the fluids* and block around them.
- Compatibility with blocks and fluids* from other mods. (e.g. fluids from the Applied Energetic's mod).
* Fluids in this case means air, water, lava and similar blocks from other mods
- Smooth models for fluids.
- A better pattern for exclusively the leaves of the tree (to avoid they touch blocks that are not part of the actual tree).
- Replacing a lot of dynamic code of the mod with static code. For coders - Replacing as much of (if not all of) the if statements and for loops. This might result in longer code, but it will be a lot faster (so higher fps).
- Partial Modification Loader port.
- 1.12.2 rewrite* and downgrade to previous versions.
* This rewrite would make the mod not require the CTM mod anymore in 1.12.2 less.
- 1.13.2 downgrade.
- 1.15.2 upgrade.

PICTURES :

They were took in macOS Catalina 10.15.4 on a hackintosh, using Forge, Optifine and Sildurs Vibrant Shaders v1.27 Extreme-VL*.
* Parralax Occlusion Mapping also add a 3d depth effects to block textues.
In this case VL means Volumetric Lightninh.
See them in the spoiler.

Credits