vec4s

vec4s are four-dimensional vectors typically composed of four floating-point components. In shader languages and graphics APIs, a vec4 usually represents x, y, z, and w components. While the term vec4s is plural, it is commonly used to refer to the data type consisting of four floats or to an array of such vectors. Each component is a 32-bit float in most implementations, yielding a 16-byte data structure.

In GLSL, vec4 is a built-in type for a vector of four floats. HLSL uses float4. Mathematically, a vec4 is a column vector that can be used to represent positions in homogeneous coordinates, directions, colors with RGBA channels, or quaternions. Operations are component-wise: add, subtract, multiply by a scalar, or by another vec4, etc. Swizzling allows access to components in different orders, such as vec4.x, vec4.yz, or vec4.rgb, depending on the language.

Common uses include transforming 3D points by a 4x4 matrix, where a point (x, y, z, 1) is multiplied to produce a new position in clip space, and colors in shaders are often handled as vec4s in RGBA form. vec4s may also participate in vector math like dot products, normalization, and linear interpolation.

Memory layout is typically tightly packed, and in performance-critical code compilers or engines may align vec4 data on 16-byte boundaries to suit SIMD units. In many APIs, vec4s integrate with textures, vertex attributes, and uniform blocks.