Rmagick custom text width/padding using annotate method - ruby-on-rails

Question

As per the documentation on Rmagick we can set the width of the rectangle within which our text is placed.
http://www.simplesystems.org/RMagick/doc/draw.html#annotate
Below is the code that we are using but we are unable to set the padding or a custom width for the text in the annotate block.
For a use case we wanted to have a custom padding for the text that we give in the annotate block.
img=Image.new(1500,600)
b=Magick::Draw.new
b.annotate(img,120,10,120,120,"5"){ |txt|
txt.pointsize = 58
txt.undercolor= "blue"
}
b.get_type_metrics(img, "5")
img.write("undercolor3.gif")
Have tried a ton number of things but couldn't make it work.Any ideas?

Answer 1

Draw a block of the desired undercolor on the image, then annotate the image such that the text is over the block.
To determine the desired size of the block, use get_type_metrics or get_multiline_type_metrics to get the dimensions of your text, then add in how much padding you want.

Answer 2

Annotate in ImageMagick does not have any option to pad the undercolor. But you can trick it. The simplest ways is to put spaces on the left and right side of your text using "\ ". But that will only pad on the left and right. In label: you can add newlines, but that does not work in annotate. You could add -interline-spacing, but that will only pad on the bottom. But here is a trick. Create text in the undercolor with a slightly larger pointsize, then write over it with your desired color text. For example:
Without padding:
convert logo.jpg -gravity center -undercolor pink -pointsize 24 -fill black -annotate +0+0 "This Is Some Text" result1.jpg
With padding:
convert logo.jpg -gravity center -pointsize 34 -undercolor pink -fill pink -annotate +0+0 "X X" -pointsize 24 -fill black -annotate +0+0 "This Is Some Text" result2.jpg
Alternately, you could just draw a pink rectangle in the center of the image of the desired size.