The Flat Colored Blocks mod exists, yes, but they don't have that type of flawless solid color that is appealing for "infinity" type rooms... you know, like where the entrance looks like it's floating in an infinite space because the walls have no shading or texture. Those types of blocks are amazing for creative, sci-fi builds. I originally saw an item like this - lapis caelestis caesicius from ExU, but since that is outdated and the block was from a version 3-4 years ago, that one isn't an option. From what I can tell, there isn't really anything like that on the mod market, or not that I could find. It would be great if it could actually become something at some point for creative types.
If there is a need a vacuum is created, nature abhors a vacuum and it will be filled. I'm not sure we have an budding mod makers who want to try and push a flat colored block out there, but you've stated a need, perhaps nature will take its course.
I do believe Chisel2's Anti-blocks fit this description, if with black borders where they do not connect to another block of the same kind
Anti-blocks kind of fit, but they do have the problem with black borders on all sides. I have a solution for that though! Make a flat colored block of your choice, and then use the EnderIO Painting Machine to paint cobblestone/whatever with the antiblock texture. This will remove the border on the blocks, giving you a flawless flat color.
I was going to mention Antiblocks as they have no light maps or shading. But as mentioned as well, they have black borders. If I remember the pictures I saw of them, if a room were to be made completely out of white antiblocks, it probably still wouldn't be an immersive "infinity" like feel because the borders in the corners where connected textures can't continue. But I guess painting machine fixes that? I've never used the painting machine, but if I had a block like this for building, I'd probably make one finally.
It definitely does. Here is an example. The left block is an Antiblock, and the right is a cobblestone painted as antiblock: And here is a ceiling i made with them:
Update: Thanks to your suggestions, I tested the antiblocks (I actually didn't even know this is what they did before now) with the painting machine. At first, it didn't work as intended because cobblestone, even after painting with the antiblock texture, still carries light map and shading, so it definitely did not work for my needs, but it led me to try painting a light block such as glowstone, which actually worked, and... well. See for yourself. The only drawback to having blocks like these is how weird and trippy it is to build with them. You can 100% get lost without block highlighting to actually see where the block starts, otherwise, like intended, it looks like it goes on forever. Like this solid here: how deep does it go? who knows, jumping in is the only way to tell now.
