Using pasture in your code

In this section we will look at how the pasture library is structured and how you can include it in your code.

The structure of pasture

pasture consists of several related libraries:

• pasture-core contains all core data structures: Point buffer types, the PointLayout type, predefined attribute definitions, as well as common math code for vectors and bounding boxes
• pasture-io contains code for doing point cloud I/O, i.e. reading and writing files in common formats
• pasture-derive contains the #[derive(PointType)] macro, which auto-generates a PointLayout from a Rust struct
• pasture-algorithms contains algorithms for working with point clouds. It is currently in a very early stage of development and contains only a limited set of algorithms. If you want to contribute, pull requests are welcome!

Using pasture in your code

For most projects, you will typically include pasture-core, pasture-io, and pasture-derive by adding the following code to your Cargo.toml:

pasture-core = "0.4.0"
pasture-io = "0.4.0"
pasture-derive = "0.4.0"

If you have your own I/O code, you probably won't need pasture-io.

Looking at the example shown in the Overview section, we can understand the basic include structure:

use pasture_core::{
    containers::{BorrowedBuffer, VectorBuffer},
    layout::attributes::POSITION_3D,
    nalgebra::Vector3,
};
use pasture_io::base::{read_all};

The two main modules that you will include from in pasture-core are containers and layout. containers contains all traits and implementations for the various point buffer types that pasture supports. They are explained in detail in the point buffers section of this tutorial. layout contains the PointLayout type and all its associated types, such as the predefined attribute definitions, which are explained in detail in the point layout section of this tutorial.

Since point clouds are spatial data, they require a bit of linear algebra, for which pasture uses the nalgebra crate. pasture-core re-exports nalgebra so that you can interface with its types while using pasture.

For doing I/O, pasture-io contains several built-in types. The simplest one is the read_all function included in the example, but the base module of pasture-io also contains traits for types that read from a point cloud file or write to a point cloud file. Point cloud I/O is explained in depth in another section of this tutorial.