Added gif-to-c converter.

tools/gif2c.rb

@@ -0,0 +1,138 @@
+#!/usr/bin/env ruby
+require 'rubygems'
+require 'rmagick'
+require 'pp'
+
+###
+# Converts a gif file to c code to enable displaying animations.
+#
+# The data format is described in animations.h
+###
+
+def compress(data, use_cutoff=true)
+	cutoff = 3
+	escape = 255
+	last = data[0]
+	result = []
+	count = 0
+	data.each do |x|
+		if x == last
+			count += 1
+		else
+			if use_cutoff
+				if count <= cutoff
+					count.times { result << last }
+				else
+					result << escape << count << last
+				end
+			else
+				result << count << last
+			end
+			count = 1
+			last = x
+		end
+	end
+	if use_cutoff
+		if count < cutoff
+			count.times { result << last }
+		else
+			result << escape << count << last
+		end
+	else
+		result << count << last
+	end
+	return result
+end
+		
+unless ARGV[0] && ARGV[1]
+	puts "Usage:"
+	puts "#{$0} <gif_file> <variable_name>"
+	puts "e.g. '#{$0} mario.gif mario'"
+	puts
+	puts "Resulting data format is described in animations.h"
+	exit 1
+end	
+
+image_file=ARGV[0]
+name=ARGV[1]
+frames = Magick::ImageList.new(image_file)
+
+puts "Found #{frames.count} frames."
+
+print "Getting colors..."
+colors = []
+frames.each do |frame|
+	frame.columns.times do |x|
+		frame.rows.times do |y|
+			color = frame.pixel_color(x, y).to_color(Magick::AllCompliance, true, 8, true)
+			colors << color
+		end
+	end
+end
+colors = colors.uniq
+
+puts " Found #{colors.count} colors."
+
+transparent = colors.select{|c| c.end_with? "00"}
+
+puts "#{transparent.count} color(s) being transparent."
+
+colors = (["#00000012", "#000000FF"] + (colors - transparent)).uniq
+puts "Using #{colors.count} colors."
+raise "Number of colors has to be 255 or less!" if colors.count>255
+
+puts
+puts
+puts "uint32_t #{name}_colors[] = {#{colors.map{|c| "0x" + c[1, 6]}.join(", ")}};"
+
+p_frame = nil
+frames_data = []
+frames.each_with_index do |frame, index|
+	data = []
+	if index==0 # first frame
+		frame.rows.times do |y|
+			frame.columns.times do |x|
+				color = frame.pixel_color(x, y).to_color(Magick::AllCompliance, true, 8, true)
+				if transparent.include? color
+					data << 0
+				else
+					data << colors.index(color)
+				end
+			end
+		end
+	else
+		frame.rows.times do |y|
+			frame.columns.times do |x|
+				color = frame.pixel_color(x, y).to_color(Magick::AllCompliance, true, 8, true)
+				p_color = p_frame.pixel_color(x, y).to_color(Magick::AllCompliance, true, 8, true)
+				
+				if color==p_color
+					data << 0
+				elsif transparent.include? color
+					data << 1
+				else
+					data << colors.index(color)
+				end
+			end
+		end
+	end
+	frames_data << data
+	p_frame = frame
+end
+
+data = frames_data.map{|d| compress(d, true)}
+
+puts "uint8_t #{name}_data[] = {\n  #{data.map{|d| d.join(",")}.join(",\n  ")}\n};"
+s=0
+puts "uint16_t #{name}_offsets[] = {#{(data.map{|d| t=s; s+=d.count; t} + [s]).join(",")}};"
+
+puts "AnimationData #{name} = {&#{name}_colors[0], &#{name}_data[0], &#{name}_offsets[0], #{colors.count}, #{frames_data.count}, 16, 16};"
+puts
+puts
+puts "Space usage:"
+puts "  Colors:      %6d bytes." % [s1=colors.count * 3]
+puts "  Data:        %6d bytes." % [s2=data.flatten.count]
+puts "  Offsets:     %6d bytes." % [s3=data.count * 2]
+puts "  TOTAL:       %6d bytes." % [s1+s2+s3]
+puts "Original size: %6d bytes." % [s4=File.new(image_file).size]
+puts "Difference:    %6d bytes." % [s1+s2+s3 - s4]