constructors: Convenience constructors
In qtbase: Interface Between R and 'Qt'

Description Usage Arguments Details Value Author(s) Examples

These functions construct some simple Qt helper objects. They offer convenience beyond that of the native constructor, largely because they might coerce from an R equivalent to a Qt object. Also, unlike C++, argument skipping is supported.

qrect(x0, y0, x1, y1)
qpoint(x, y)
qsize(width, height)
qpolygon(x = NULL, y = NULL)
qfont(family = baseFont$family(), pointsize =
      baseFont$pointSize(), weight = baseFont$weight(),
      italic = baseFont$style() == Qt$QFont$StyleItalic,
      baseFont = Qt$QApplication$font())
qpen(brush = qbrush(), width = 0L, style = Qt$Qt$SolidLine,
                 cap = Qt$Qt$SquareCap, join = Qt$Qt$BevelJoin)
qbrush(color = qcolor(), style = Qt$Qt$SolidPattern)
qcolor(red = 0, green = 0, blue = 0, alpha = 255)
qtransform(m11 = 1.0, m12 = 0.0, m13 = 0.0, m21 = 0.0, m22 = 1.0,
           m23 = 0.0, m31 = 0.0, m32 = 0.0, m33 = 1.0)

`x0`	Top-left X coordinate. If a vector of length two, taken as `x0` and `x1`. If a 2x2 `matrix`, the columns represent the X and Y positions. If missing, a "null" rectangle is returned.
`y0`	Top-left Y coordinate. If a vector of length two, taken as `y0` and `y1`.
`x1`	Bottom-right X coordinate.
`y1`	Bottom-right Y coordinate.
`x`	X coordinate. If a vector of length two, taken as `x` and `y`. For `qpolygon`, passed to `xy.coords`.
`y`	Y coordinate. For `qpolygon`, passed to `xy.coords`.
`width`	Width for the size. If a vector of length two, taken as `width` and `height`. If missing, a "null" size is returned. For `qpen`, width of the line.
`height`	Height for the size.
`family`	Font family name.
`pointsize`	Font point size.
`weight`	Font weight (bold).
`italic`	Whether font is italicized.
`baseFont`	The base font to use for the defaults. By default, this is the global application font.
`brush`	Something coercible to a `QBrush` object via `qbrush(brush)`.
`style`	Line dashing for `qpen`, pattern type for `qbrush`.
`cap`	Line cap style.
`join`	Line join style.
`color`	Something coercible to a `QColor` via `qcolor(color)`.
`red`	Red component, 0-255. If a string, taken as color name and converted. If a matrix, taken as output of `col2rgb`.
`green`	Green component, 0-255.
`blue`	Blue component, 0-255.
`alpha`	Alpha component, 0-255.
`m11`	Horizontal scaling factor
`m12`	Vertical shearing factor
`m13`	Horizontal projection factor
`m21`	Horizontal shearing factor
`m22`	Vertical scaling factor
`m23`	Vertical projection factor
`m31`	Horizontal translation factor
`m32`	Vertical translation factor
`m33`	Division factor

For structures with a F variant, like QSizeF, the variant is chosen based on the type of the input. If the values are double, a QSizeF instance is returned, otherwise an instance of QSize.

An instance, RQtObject

Michael Lawrence, Deepayan Sarkar

## notice the coercion chaining:
redColor <- qcolor("red")
redBrush <- qbrush("red")
redPen <- qpen("red")
blackPen <- qpen()

## Qt's constructor uses width/height, not x1/y1
rect <- qrect(as.matrix(Qt$QRectF(1, 1, 5, 5)))
as.matrix(rect)

## Creates 'QRect' not 'QRectF'; integer input
qrect(range(1:10), range(2:5))

qsize(as.vector(qpoint(5, 5)))

mono_it <- qfont("monospace", italic = TRUE)