Glossary

AABB :

Axis-Aligned Bounding Box (AABB) - A bounding box aligned with the axes of the coordinate system.

Buffer :

A section of memory used for temporary data storage.

BVH :

Bounding Volume Hierarchy (BVH) - A tree-based acceleration structure containing primitive 3D objects that speeds up ray-casting and various algorithms.

Camera Space :

(Also known as; View Space, Eye Space) - 3D coordinates projected relative to the camera, including relative depth.

Cross Product :

An operation between two vectors that returns a vector perpendicular to the input vectors. The magnitude of this vector is the product of the magnitudes of the input vectors and the sine of the angle between them.

Lerp :

Linear Interpolation.

Depth Buffer :

An additional screen-space buffer that provides depth information.

DOF :

Depth of Field (DOF) - The distance between the nearest and the furthest objects that are in acceptably sharp focus in an image captured with a camera.

Dot Product :

An operation between two vectors that returns the product of their magnitudes and the cosine of the angle between them.

Epsilon :

A very small value, mostly used to prevent floating-point inaccuracies and to set ray marching limits.

Focal Length :

A camera property that indicates how strongly it converges or diverges light. It is inversely proportional to the Field of View (FOV).

FOV :

Field of View (FOV) - The angular extent of the world that is seen. It is inversely proportional to the focal length.

Length :

The magnitude of a vector.

Magnitude :

The length of a vector.

Mesh :

A collection of faces, edges, and vertices that define an object's shape.

Model Space :

(Also known as; Object Space, Local Space) - 3D coordinates relative to another point of reference, typically used to store meshes of individual models or objects.

Surface Normal :

A vector perpendicular to the surface of an object.

Pen :

A vanilla Scratch extension used to draw on the screen.

Procedural :

Defined by code.

Rasterizer :

An algorithm that draws objects to the screen by filling in shapes pixel-by-pixel.

Ray :

Defined by its origin (a position in 3D space where the ray starts) and its direction.

Screen Space :

(Also known as; Clip Space) - 2D information of 3D coordinates projected to the screen, without depth information.

SDF :

Signed Distance Field (SDF) - A function defining distance to the surface of an object, with interior points being negative and exterior points being positive.

Vector :

An object having direction as well as magnitude, used to determine the position of one point in space relative to another.

Vertex :

A point with a coordinate vector.

Viewing Frustum :

The region of space in the modeled world that may appear on the screen.

World Space :

3D coordinates relative to the center of the world, typically (0, 0, 0).