Miniature is a OptiFine shader (but also works on newer versions of Iris). It offers blocky shadows and reflections in water, ice and other commonly reflective blocks, and a slight overhaul of emissive lighting; all in a very lightweight way. Its goal, above all else, is to keep with Minecraft's model-like appearance without compromising performance. It wasn't built with mod support in mind: that is, there's no code for specific mods, although its simplicity allows it to work with mods most shaders don't, like dimension mods.