What is the difference between a texture pack and a shader?

Question

Everyone knows what texture packs are. They make blocks look different, as set by the author of the texture pack. But now, I'm hearing about something new called a shader.

1. What is a shader?
2. How is it different from a texture pack?

Answer 1

Textures define what an object's surface will look like: Take a wire-frame cube on which you put your own surface (texture). In context of graphics, each point is called a vertex, so a cube/block is made of 8 vertices and 6 faces.

Imagine that you have foldable tent in real life: the texture will be like the fabric that is put on the wire-frame.

Shaders on the other hand, in 3D graphics, are a description language which defines how to change texture color, lightness and other things dynamically. In graphics it is used to simulate lighting effects, depth, other things.

If you want to find out about them more and have more technical details good start is Wikipedia: http://en.wikipedia.org/wiki/Shader or any 3D graphics tutorial, because texture and shaders are some of the most fundamental things in 3D object rendering.

They are very different things.

What does that mean in context of Minecraft?

• Now you could not only have high quality textures on blocks, but those blocks could react to lighting (for example they could be only half-lit), or they could cast shadows on each other.
• Shaders allow for more realistic lighting modifications (imagine a colored lamp which colors the room, except where the player casts a shadow).
• It also allows more realistic water surfaces and various effects such as lens flares, depth of view, blur effects, depending how the shaders are implemented.

So in a nut-shell the answers to your questions are:

1. Shaders are short scripts that many games use to enhance their graphics, make light behave more realistically, objects change color, simulate refraction, add stylistic chocies (e.g. Borderlands' black outlines), etc.

2. No, they are not comparable. Textures are pre-rendered images applied to the faces of 3D models (in this case, blocks), while shaders work with and affect what the textures will ultimately look like on your screen, depending on various conditions, such as nearby light sources. In other games it is what makes swords shine and water look realistic.