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 which returns a vector perpendicular to the two input vectors. The magnitude of this vector is the product of the magnitudes of the input vectors and the sine of the angle formed between the vectors.

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).