Movement speed

A modification to the way movement speeds work, depending on the surface the player (or monster) is on. It disables speed potions and causes player speed to instead depend on the "roughness" of material underfoot. It encourages the building of roads to allow fast travel, since grass is not a favorable material.

It provides the following tweaks:

• Movement across hard surfaces or materials used in roads (cobble, brick, gravel, planks, wool, iron, etc.) is faster
• Soft surfaces (grass, dirt, etc.) is the usual speed
• Materials that you would expect to slow you down (tall grass, snow, crops, Groth, reeds, etc.) reduce speed.
• Soul sand reduces speed the most.
• Potions of swiftness have had their recipe and effect removed
• Note that materials in the same class will provide the same bonus or detriment to movement - travel across cobble is equally as fast as travel across gravel, and travel across crops is equally as slow as travel across sand.
• Snow applies a movement penalty in addition to whatever modifier the block beneath it applies. This means for example that you will move faster on snow above cobble than you will on snow above leaves.