OptiFine HD — Reference
Blocks & Connected Textures (CTM)
OptiFine enhances the appearance of blocks through the Connected Textures Mod (CTM) system. This allows textures to connect seamlessly when placed next to each other, removing the grid-like appearance of blocks like glass, bookshelves, and sandstone.
| Method | Description |
|---|---|
| ctm | Standard 8-way connection (47 tiles) used for glass and seamless surfaces. |
| ctm_compact | A more efficient 5-tile version of the 8-way connection. |
| horizontal | Connects blocks only on the left and right (e.g., bookshelves). |
| vertical | Connects blocks only above and below. |
| random | Picks a tile at random from a set to break up repetitive patterns. |
| repeat | Repeats a large pattern over a grid of blocks. |
| overlay | Overlays a texture onto neighboring blocks for smooth transitions (e.g., grass to sand). |
Better Grass & Snow: * Better Grass: Extends the top grass texture to the sides of the block if the adjacent block is also grass. * Better Snow: Adds snow textures to the sides of transparent blocks (like fences or grass) when they are surrounded by snow.
Mobs & Custom Entity Models (CEM)
OptiFine allows for extensive customization of mobs and creatures through two primary systems: Random Entities and Custom Entity Models (CEM).
Random Entities
This feature allows resource packs to assign multiple different textures to a single mob type. These textures can be chosen randomly or based on specific conditions.
Customization Properties: * Biomes: Assign specific textures to mobs spawning in certain biomes (e.g., white wolves in snowy biomes). * Height: Change textures based on the Y-level of the mob. * Health: Change textures as a mob takes damage. * NBT Rules: Use specific entity data (like names or equipment) to trigger unique textures.
Custom Entity Models (CEM)
CEM allows resource packs to completely replace the 3D model of any entity. This can be used to add new limbs, change proportions, or create entirely new creature designs using .jem and .jpm files.
Items & Custom Item Textures (CIT)
Custom Item Textures (CIT) allow items to change their appearance based on various criteria defined in .properties files within a resource pack.
CIT Trigger Criteria: * Item Name: Change the texture of a sword if it is renamed to "Excalibur" in an anvil. * Enchantments: Apply unique textures or glints based on the enchantments present on the item. * Stack Size: Change the appearance of a stack of items as it grows (e.g., a pile of gold coins). * Damage/Durability: Visually show an item breaking as its durability decreases.