Grid unit width and font face

I think you are doing this in the wrong order. You need to set the gpar
on the viewport, then compute the grid.rect.

grid.rect(width=unit(1,'strwidth','Some text'),draw=T, gp=gpar(font=2))
grid.text('Some text',y=0.4,gp=gpar(font=2),draw=T)

is one way to do it: pushing a viewport is another.

The factor does depend on the font, family, pointsize, but see e.g.

strwidth('Some text', units='in')

[1] 0.7503255

strwidth('Some text', units='in', font = 2)

[1] 0.7965495


On Fri, 12 Aug 2011, S?bastien Bihorel wrote:

Dear R-users,

When one defines a grid unit object using the 'strwidth' dimension, it
seems that the default plain font is assumed as the following example
illustrates. Is there a way to either make use of a font option when
creating a unit object or to know the factor that exists between the
width of the same text printed in plain and in bold? This might be
dependent on the font, though...

require(grid)

grid.rect(width=unit(1,'strwidth','Some text'),draw=T)

grid.text('Some text',draw=T) # fits
nicely in the box
grid.text('Some text',y=0.4,gp=gpar(font=2),draw=T) # partially
outside the box

Thank you in advance for your input on this issue.

Sebastien