Coordinate spaces

**Coordinate System: **Left handed, Z-Up, X-axis is forward, Y-axis is right

Matrix

Row addressable M[RowIndex][ColumnIndex]
Matrix stored as row major m[0]-m[3] = first row, m[4]-m[7] = second row
Matrices are post multiplied (x * M * V * P)
Which basically just means you can treat everything as column addressable, column major and pretending matrices are pre-multiplied

Space in Unreal	Other Names	Description
Tangent		Orthogonal (can deviate after interpolation), can be left or right handed. The TangentToLocal transform contains rotation only, so it is OrthoNormal (can be inverted by transposing).
Local	Object Space	Orthogonal, can be left or right handed (triangle cull order needs adjustment). The LocalToWorld transform contains rotation, non-uniform scaling (including negative non-uniform scaling which can change the winding order), and translation.
World		The WorldToView transform contains only rotation and translation, so distances in View space are the same as in World space.
TranslatedWorld		World TranslatedWorld - PreviewTranslation TranslatedWorld World + PreviewTranslation
View	CameraSpace	The ViewToClip transform contains scale on x and y, but no translation (which would be an off center projection). It scales and translates z. It also applies a projection to convert into the homogeneous ClipSpace.
Clip	HomogeniousCoordinates, PostProjectionSpace, ProjectionSpace	After the perspective projection matrix was applied. Note that W in Clip space is the same as View Space Z.
Screen	NormalizedDeviceCoordinates from OpenGL	After the perspective divide: left/right -1,1 top/bottom 1,-1 near/far 0,1 (OpenGL RHI needs to transform this to -1,1)
Viewport	ViewportCoordinates, WindowCoordinates	In pixels: left/right 0,width-1 top/bottom 0,height-1

Transformation between spaces should always be named using the form X To Y.

Examples: