Added ICO and MIX libraries

lib/ico.rb

@@ -0,0 +1,144 @@
+require "stringio"
+
+module W3DHubLauncher
+  class ICO
+    PNG_IDENT = "\211PNG\r\n\032\n".force_encoding("ASCII-8BIT").freeze
+
+    IconDirectory = Struct.new(:reserved, :type, :image_count)
+
+    IconDirectoryEntity = Struct.new(
+      :width,
+      :height,
+      :palette_size,
+      :reserved,
+      :color_planes,
+      :bit_depth,
+      :image_size,
+      :image_offset
+    )
+
+
+    def initialize(file:)
+      @file = StringIO.new(File.binread(file))
+
+      @images = []
+
+      parse
+    end
+
+    def directory
+      @icon_directory
+    end
+
+    def images
+      @images
+    end
+
+    # SEE: https://en.wikipedia.org/wiki/ICO_(file_format)
+    def parse
+      # Parse IconDirectory
+      @icon_directory = IconDirectory.new(
+        read_u16, read_u16, read_u16
+      )
+
+      @icon_directory.image_count.times do
+        @images << IconDirectoryEntity.new(
+          read_u8,
+          read_u8,
+          read_u8,
+          read_u8,
+          read_u16,
+          read_u16,
+          read_u32,
+          read_u32
+        )
+
+        @images.last.width  = 256 if @images.last.width == 0
+        @images.last.height = 256 if @images.last.height == 0
+      end
+    end
+
+    def read_u8
+      @file.read(1).unpack1("C")
+    end
+
+    def read_u16
+      @file.read(2).unpack1("v")
+    end
+
+    def read_u32
+      @file.read(4).unpack1("V")
+    end
+
+    def select_pngs
+      @images.select do |image|
+        image_png?(image)
+      end
+    end
+
+    def image_png?(image)
+      @file.pos = image.image_offset
+      buf = @file.read(8).unpack1("a*")
+
+      buf == PNG_IDENT
+    end
+
+    def select_bmps
+      @images.select do |image|
+        image_bmp?(image) && image.palette_size.zero? && image.bit_depth == 32
+      end
+    end
+
+    def image_bmp?(image)
+      !image_png?(image)
+    end
+
+    def to_rgba32_blob(image)
+      @file.pos = image.image_offset
+      buf = StringIO.new(@file.read(image.image_size))
+
+      raise NotImplementedError "Cannot parse png based icons!" unless image_bmp?(image)
+
+      raise NotImplementedError "Cannot parse #{image.bit_depth}" unless image.bit_depth == 32
+
+      blob = "".force_encoding("ASCII-8BIT")
+
+      width  = image.width
+      height = image.height - 1
+
+      image.height.times do |y|
+        image.width.times do |x|
+          buf.pos = ((height - y) * width + x + 10) * 4
+
+          blue  = buf.read(1)
+          green = buf.read(1)
+          red   = buf.read(1)
+          alpha = buf.read(1)
+
+          blob << red
+          blob << green
+          blob << blue
+          blob << alpha
+        end
+      end
+
+      Gosu::Image.from_blob(image.width, image.height, blob)
+    end
+
+    def image_data(image)
+      @file.pos = image.image_offset
+      StringIO.new(@file.read(image.image_size)).string
+    end
+
+    def save(image, filename)
+      puts filename
+      if image_bmp?(image)
+        puts :gosu_image
+        to_rgba32_blob(image).save(filename)
+      else
+        puts :png
+        File.open(filename, "wb") { |f| f.write(image_data(image)) }
+      end
+    end
+  end
+end