qmap: Mapping coordinates
In qtpaint: Qt-Based Painting Infrastructure

Description Usage Arguments Value Author(s)

Transforms X and Y coordinates with a Qt-style transformation matrix. The advantage over direct use of Qt is vectorization.

1	qvmap(m, x, y)

`m`	A matrix encoding the transformation, or something coercible to a matrix, like a C++ `QTransform` instance
`x`	X coordinates; if `y` is missing, should be something coercible to a numeric vector or matrix. If the vector coercion succeeds, the vector is coerced to a matrix with `matrix(x, ncol = 2, byrow = TRUE)`. The first column is taken as X, the second as Y.
`y`	Y coordinates, optional

The mapped coordinates, as a two column (X, Y) matrix, unless y is missing, in which case an attempt is made to coerce the result to the class of x, if any.

Michael Lawrence

qtpaint documentation built on May 2, 2019, 4 p.m.