#!/usr/bin/env ruby
# $Id: starter_color.rb,v 1.1.2.2 2008/02/28 14:49:59 rjs Exp $
# Starter color:
# Demonstrate the basic use of supported color spaces
#
# Apply the following color spaces to text and vector graphics:
# - gray
# - rgb
# - cmyk
# - iccbasedgray/rgb/cmyk
# - spot
# - lab
# - pattern
# - shadings
#
# Required software: PDFlib/PDFlib+PDI/PPS 7
# Required data: none

require 'PDFlib'

# This is where the data files are. Adjust as necessary.
searchpath = "../data"
outfile = "starter_color.pdf"
title = "Starter Color"

y = 800
x = 50
xoffset1=80
xoffset2 = 100
yoffset = 70
r = 30

begin
    p = PDFlib.new

	p.set_parameter("SearchPath", searchpath)

	# This means we must check return values of load_font() etc.
	p.set_parameter("errorpolicy", "return")

	# we use "utf8" as textformat, this allows to use unicode encoding
	p.set_parameter("textformat", "utf8");

	if (p.begin_document(outfile, "") == -1)
        raise "Error: " + p.get_errmsg()
    end

	p.set_info("Creator", "PDFlib Cookbook")
	p.set_info("Title", title + " $Revision: 1.1.2.2 $")

	# Load the font
	font = p.load_font("Helvetica", "unicode", "")
	if font == -1
        raise "Error: " + p.get_errmsg()
    end

	# Start the page
	p.begin_page_ext(0, 0, "width=a4.width height=a4.height")

	p.setfont(font, 14)


	# -------------------------------------------------------------------
	# Use default colors
	#
	# If no special color is set the default values will be used. The
	# default values are restored at the beginning of the page.
	# 0=black in the Gray color space is the default fill and stroke
	# color in many cases, as shown in our sample.
	# -------------------------------------------------------------------


	# Fill a circle with the default black fill color
	p.circle(x, y-=yoffset, r)
	p.fill()

	# Output text with default black fill color
	p.fit_textline("Circle and text filled with default color {gray 0}",
		x+xoffset2, y, "")

	p.fit_textline("1.", x+xoffset1, y, "")

	# -------------------------------------------------------------------
	# Use the Gray color space
	#
	# Gray color is defined by Gray values between 0=black and 1=white.
	# -------------------------------------------------------------------


	# Using setcolor(), set the current fill color to a light gray
	# represented by (0.5, 0, 0, 0) which defines 50% gray. Since gray
	# colors are defined by only one value, the last three function
	# parameters must be set to 0.

	p.setcolor("fill", "gray", 0.5, 0, 0, 0)

	# Fill a circle with the current fill color defined above
	p.circle(x, y-=yoffset, r)
	p.fill()

	# Output text with the current fill color
	p.fit_textline("Circle and text filled with {gray 0.5}",
		x+xoffset2, y, "")

	# Alternatively, you can set the fill color in the call to
	# fit_textline() using the "fillcolor" option. This case applies the
	# fill color just the single function call. The current fill color
	# won't be affected.

	p.fit_textline("2.", x+xoffset1, y, "fillcolor={gray 0.5}")


	# --------------------------------------------------------------------
	# Use the RGB color space
	#
	# RGB color is defined by RGB triples, i.e. three values between 0 and
	# 1 specifying the percentage of red, green, and blue.
	# (0, 0, 0) is black and (1, 1, 1) is white. The commonly used RGB
	# color values in the range 0–255 must be divided by 255 in order to
	# scale them to the range 0–1 as required by PDFlib.
	# --------------------------------------------------------------------


	# Use setcolor() to set the fill color to a grass-green
	# represented by (0.1, 0.95, 0.3, 0) which defines 10% red, 95% green,
	# 30% blue. Since RGB colors are defined by only three values, the last
	# function parameter must be set to 0.

	p.setcolor("fill", "rgb", 0.1, 0.95, 0.3, 0)

	# Draw a circle with the current fill color defined above
	p.circle(x, y-=yoffset, r)
	p.fill()

	# Output a text line with the RGB fill color defined above
	p.fit_textline("Circle and text filled with {rgb 0.1 0.95 0.3}",
		x+xoffset2, y, "")

	# Alternatively, you can set the fill color in the call to
	# fit_textline() using the "fillcolor" option. This case applies the
	# fill color just the single function call. The current fill color
	# won't be affected.

	p.fit_textline("3.", x+xoffset1, y, "fillcolor={rgb 0.1 0.95 0.3}")


	# --------------------------------------------------------------------
	# Use the CMYK color space
	#
	# CMYK color is defined by four CMYK values between 0 = no color and
	# 1 = full color representing cyan, magenta, yellow, and black values
	# (0, 0, 0, 0) is white and (0, 0, 0, 1) is black.
	# --------------------------------------------------------------------


	# Use setcolor() to set the current fill color to a pale
	# orange, represented by (0.1, 0.7, 0.7, 0.1) which defines 10% Cyan,
	# 70% Magenta, 70% Yellow, and 10% Black.

	p.setcolor("fill", "cmyk", 0.1, 0.7, 0.7, 0.1)

	# Fill a circle with the current fill color defined above
	p.circle(x, y-=yoffset, r)
	p.fill()

	# Output a text line with the CMYK fill color defined above
	p.fit_textline("Circle and text filled with" + \
		" {cmyk 0.1 0.7 0.7 0.1}", x+xoffset2, y, "")

	# Alternatively, you can set the fill color in the call to
	# fit_textline() using the "fillcolor" option. This case applies the
	# fill color just the single function call. The current fill color
	# won't be affected.

	p.fit_textline("4.", x+xoffset1, y, "fillcolor={cmyk 0.1 0.7 0.7 0.1}")


	# --------------------------------------------------------------------
	# Use a Lab color
	#
	# Device-independent color in the CIE L*a*b* color space is specified
	# by a luminance value in the range 0-100 and two color values in the
	# range -127 to 128. The first value contains the green-red axis,
	# while the second value contains the blue-yellow axis.
	# --------------------------------------------------------------------


	# Set the current fill color to a loud blue, represented by
	# (100, -127, -127, 0). Since Lab colors are defined by only three
	# values, the last function parameter must be set to 0.

	p.setcolor("fill", "lab", 100, -127, -127, 0)

	# Fill a circle with the fill color defined above
	p.circle(x, y-=yoffset, r)
	p.fill()

	# Output a text line with the Lab fill color defined above
	p.fit_textline("Circle and text filled with {lab 100 -127 -127}",
		x+xoffset2, y, "")

	# Alternatively, you can set the fill color in the call to
	# fit_textline() using the "fillcolor" option. This case applies the
	# fill color just the single function call. The current fill color
	# won't be affected.

	p.fit_textline("5.", x+xoffset1, y, "fillcolor={lab 100 -127 -127}")


	# ---------------------------------------------------------------
	# Use an ICC based color
	#
	# ICC-based colors are specified with the help of an ICC profile.
	# ---------------------------------------------------------------


	# Load the sRGB profile. sRGB is guaranteed to be always available
	icchandle = p.load_iccprofile("sRGB", "usage=iccbased")
	if icchandle == -1
        raise "Error: " + p.get_errmsg()
    end

	# Set the sRGB profile. (Accordingly, you can use
	# "setcolor:iccprofilergb" or "setcolor:iccprofilegray" with an
	# appropriate profile)

	p.set_value("setcolor:iccprofilergb", icchandle)

	# Use setcolor() with the "iccbasedrgb" color space to set the current
	# fill and stroke color to a grass-green, represented
	# by the RGB color values (0.1 0.95 0.3 0) which define 10% Red,
	# 95% Green, and 30% Blue. Since iccbasedrgb colors are defined by only
	# three values, the last function parameter must be set to 0.

	p.setcolor("fill", "iccbasedrgb", 0.1, 0.95, 0.3, 0)

	# Fill a circle with the ICC based RGB fill color defined above
	p.circle(x, y-=yoffset, r)
	p.fill()

	# Output a text line with the ICC based RGB fill color defined above
	p.fit_textline("Circle and text filled with {iccbasedrgb 0.1 0.95 0.3}",
		x+xoffset2, y, "")

	# Alternatively, you can set the fill color in the call to
	# fit_textline() using the "fillcolor" option. This case applies the
	# fill color just the single function call. The current fill color
	# won't be affected.

	p.fit_textline("6.", x+xoffset1, y,
		"fillcolor={iccbasedrgb 0.1 0.95 0.3}")


	# --------------------------------------------------------------------
	# Use a spot color
	#
	# Spot color (separation color space) is a predefined or arbitrarily
	# named custom color with an alternate representation in one of the
	# other color spaces above this is generally used for preparing
	# documents which are intended to be printed on an offset printing
	# machine with one or more custom colors. The tint value (percentage)
	# ranges from 0 = no color to 1 = maximum intensity of the spot color.
	# --------------------------------------------------------------------


	# Define the spot color "PANTONE 281 U" from the builtin color
	# library PANTONE

	spot = p.makespotcolor("PANTONE 281 U")

	# Set the spot color "PANTONE 281 U" with a tint value of 1 (=100%)
	# and output some text. Since spot colors are defined by only two
	# values, the last two function parameters must be set to 0.

	p.setcolor("fill", "spot", spot, 1.0, 0, 0)

	# Fill a circle with the ICC based RGB fill color defined above
	p.circle(x, y-=yoffset, r)
	p.fill()

	p.fit_textline("Circle and text filled with " + \
		"{spotname {PANTONE 281 U} 1}", x+xoffset2, y, "")

	# Alternatively, you can set the fill color in the call to
	# fit_textline() using the "fillcolor" option. This case applies the
	# fill color just the single function call. The current fill color
	# won't be affected.

	p.fit_textline("7.", x+xoffset1, y,
		"fillcolor={spotname {PANTONE 281 U} 1}")

	# or
	p.fit_textline("7.", x+xoffset1, y, "fillcolor={spot " + spot.to_s + " 1}")


	# ----------------------------------------------------------
	# For using the Pattern color space, see the Cookbook topics
	# graphics/fill_pattern and images/background_pattern.
	# ----------------------------------------------------------


	# ---------------------------------------------------------
	# For using the Shading color space, see the Cookbook topic
	# color/color_gradient.
	# ---------------------------------------------------------


	p.end_page_ext("")

	p.end_document("")

rescue  PDFlibException => pe
  print "PDFlib exception occurred:\n"
  print "[" + pe.get_errnum.to_s + "] " + pe.get_apiname + \
		": " + pe.get_errmsg + "\n"
rescue  Exception => e
  print e.backtrace.join("\n") + "\n" + e.to_s
ensure
  p.delete() if p
end

# vim: sw=4
