Simple text effects for cairo/pango rendered text

cairo-pango-fancy-text.rb

require 'cairo'
require 'pango'

width, height = 600, 600

surface = Cairo::ImageSurface.new(:argb32, width, height)
cr = Cairo::Context.new(surface)

cr.save do 
	cr.set_operator(Cairo::OPERATOR_CLEAR)
	cr.set_source_rgba(1.0, 1.0, 1.0, 0)
	cr.paint(1.0)
end

def grad_vl(y1,y2,col1=nil,col2=nil,&block)
	pattern= Cairo::LinearPattern.new(0, y1, 0, y2)
	{0=>col1,1=>col2}.each do |offset, col|
		next unless col
		case col.size
		when 3
			pattern.add_color_stop_rgb(offset, *col)
		when 4
			pattern.add_color_stop_rgba(offset, *col)
		end
	end
	yield(pattern) if block_given?
	pattern
end

text = "Birthday"

font = Pango::FontDescription.new("Droid Sans Bold 104")

layout = cr.create_pango_layout

layout.font_description = font
layout.set_text(text)
	

ink, log = layout.get_pixel_extents

cr.save do
	cr.pseudo_blur(5) do
		cr.set_source_rgba(0,0,0,0.3)
		cr.show_pango_layout(layout)
	end
end

cr.set_source(grad_vl(ink.y, ink.height, [0,0.4,0.8], [0,0.2,0.5]))
cr.show_pango_layout(layout)

x,y = ink.x+ink.width, ink.y+ink.height/2
x2 = ink.x+(ink.width/2)
x3 = ink.x
ywave_factor = ink.height / 12.0
xwave_factor = ink.width / 6.0

cr.save do
#cr.rectangle(ink.x,ink.y,ink.width, ink.height/2.0)
cr.new_path
cr.move_to(ink.x, ink.y)
cr.line_to(ink.x+ink.width, ink.y)
cr.line_to(ink.x+ink.width, ink.y+ink.height/2)
cr.curve_to(x - xwave_factor, y-ywave_factor, x2 + xwave_factor, y-ywave_factor, x2, y)

cr.curve_to(x2 - xwave_factor, y+ywave_factor, x3 + xwave_factor, y+ywave_factor, x3, y)
#cr.line_to(ink.x, ink.y+ink.height/2)
cr.line_to(ink.x, ink.y)

cr.clip


cr.set_source(grad_vl(ink.y, ink.height, [1,1,1,0.1], [1,1,1,0.3]))
cr.show_pango_layout(layout)
end

if false
cr.set_source_rgba(1,0.7,0,0.5)
pts =[x,y,x3,y,x - xwave_factor, y-ywave_factor, x2 + xwave_factor, y-ywave_factor, x2 - xwave_factor, y+ywave_factor, x3 + xwave_factor, y+ywave_factor]
until pts.empty?
	x = pts.shift
	y = pts.shift
	cr.rectangle(x-4,y-4,8,8)
	cr.fill
end
end



surface.write_to_png('birthday-text.png')