This example is still awful and messy, but it's better than what was there... Needs chunky_png and skrift gem's installed

example/test.rb

@@ -1,4 +1,5 @@
 require 'rubygems'
+require 'skrift'
 require 'bundler'
 require 'chunky_png'
 Bundler.setup(:default, :development)
@@ -8,95 +9,164 @@ $LOAD_PATH.unshift(File.dirname(__FILE__))
 
 require 'X11'
 
-display = X11::Display.new
+
-screen = display.screens.first
+dpy = display = X11::Display.new
+screen = dpy.screens.first
 root = screen.root
 wid = display.new_id
-display.write_request(X11::Form::CreateWindow.new(
+
-  screen.root_depth,
+dpy.create_window(
-  wid,
+  screen.root_depth, wid, root,
-  root,
+  0, 0, # x,y
-  0,  #x
+  1000, 600, # w,h
-  0,  #y
-  1000,#w
-  600,#h
   0,
   X11::Form::InputOutput,
   X11::Form::CopyFromParent,
   X11::Form::CWBackPixel |
     X11::Form::CWEventMask,
-  [0xff8844, # RGB background
+  [0x0, # RGB background
    X11::Form::SubstructureNotifyMask |
-#   X11::Form::StructureNotifyMask    | ## Move
+   X11::Form::StructureNotifyMask    | ## Move
    X11::Form::ExposureMask           |
    X11::Form::KeyPressMask           |
    X11::Form::ButtonPressMask
   ]
-))
+)
+
+def set_window_opacity(dpy, wid, opacity)
+  dpy.change_property(
+    X11::Form::Replace,
+    wid, dpy.atom(:_NET_WM_WINDOW_OPACITY),
+    X11::Form::CardinalAtom, 32,
+    [(0xffffffff * opacity).to_i].pack("N").split(//).map(&:ord)
+  )
+end
+
+
+set_window_opacity(dpy, wid, 0.8)
+#p dpy.display_info
+
+#reply = dpy.query_extension("XKEYBOARD")
+
+$kmap = nil
+def update_keymap(dpy)
+  reply = dpy.get_keyboard_mapping
+
+
+  if reply
+    $kmap = reply.keysyms.map do |c|
+      if c == 0
+        nil
+      elsif X11::KeySyms[c]
+        X11::KeySyms[c]
+      elsif c < 0x100
+        c.chr(Encoding::ISO_8859_1)
+      elsif c.between?(0xffb0, 0xffb9)
+        "KP_#{c-0xffb0}".to_sym
+      elsif c.between?(0xffbe, 0xffe0)
+        "F#{c-0xffbe+1}".to_sym
+      elsif c.between?(0xff08, 0xffff)
+        # FIIXME:
+        raise "keyboard_#{c.to_s(16)}".to_s
+      elsif c.between?(0x01000100, 0x0110FFFF)
+        (c-0x01000100).
+        chr(Encoding::UTF_32) rescue c.to_s(16)
+      else
+        raise "unknown_#{c.to_s(16)}"
+      end
+    end.each_slice(reply.keysyms_per_keycode).to_a
+    #ks = ks.map {|s| s.compact.sort_by{|x| x.to_s}.uniq }.to_a # This is for testing/ease of reading only
+    p $kmap[47-dpy.display_info.min_keycode]
+  end
+end
+
+
+def lookup_keysym(dpy,  event)
+  update_keymap(dpy) if !$kmap
+  p $kmap[event.detail-dpy.display_info.min_keycode]
+end
+
 puts "Mapping"
-display.write_request(X11::Form::MapWindow.new(wid))
+dpy.map_window(wid)
-# Creating GC
-gc = display.new_id
-display.write_request(X11::Form::CreateGC.new(
-  gc, screen.root,
-  X11::Form::ForegroundMask,
-  [0xff0000,  # RGB foreground
-  ]
-))
 
-$gc2 = display.new_id
+$gc = gc = dpy.create_gc(wid, foreground: 0xff0000)
-display.write_request(X11::Form::CreateGC.new(
+$gc2 = dpy.create_gc(wid,foreground: 0xffffff, background: 0x444444)
-  $gc2,
+$gc3 = dpy.create_gc(wid)
-  screen.root,
-  X11::Form::ForegroundMask|X11::Form::BackgroundMask,
-  [0xffffff,  # RGB foreground
-   0x444444,
-  ]
-))
-
-$gc3 = display.new_id
-display.write_request(X11::Form::CreateGC.new(
-  $gc3,
-  screen.root,
-  0, []
-))
 
 
 puts "Main loop"
-p gc
 
-# This will wait for a reply
+#p dpy.list_fonts(10,  "*7x13*").names.map(&:to_s)
-p display.write_sync(X11::Form::ListFonts.new(10,  "*7x13*"),
-  X11::Form::ListFontsReply).names.map(&:to_s)
 
-fid = display.new_id
+fid = dpy.new_id
-display.write_request(X11::Form::OpenFont.new(fid, "7x13"))
+dpy.open_font(fid, "-misc-fixed-bold-r-normal--13-120-75-75-c-70-iso10646-1")
-display.write_request(X11::Form::ChangeGC.new($gc2, X11::Form::FontMask, [fid]))
+#"-bitstream-courier 10 pitch-medium-r-normal--0-0-0-0-m-0-iso10646-1")
+dpy.change_gc($gc2, X11::Form::FontMask, [fid])
 
 $png = ChunkyPNG::Image.from_file('genie.png')
-p $png.width
-p $png.height
 
-def redraw(display, wid, gc)
+$data = ""
-  p [:redraw, gc]
-  display.write_request(X11::Form::PolyFillRectangle.new(
-    wid, gc,
-    [X11::Form::Rectangle.new(20,20, 60, 80)]
-  ))
-
-  display.write_request(X11::Form::ClearArea.new( false, wid, 30, 30, 5, 5))
-  display.write_request(X11::Form::ImageText8.new(wid, $gc2, 30, 70, "Hello World"))
-
-  depth = 24
-  # FIXME: The colors are wrong
-  #  pixels.pack("N*")
-  data = ""
 $png.pixels.each do |px|
   str = [px].pack("N")
-    data << str[2] << str[1] << str[0] << str[3]
+  if str[3] == "\x00"
+    $data << "\0\0\0\0".force_encoding("ASCII-8BIT")
+  else
+    $data << str[2] << str[1] << str[0] << str[3]
   end
-  display.write_request(X11::Form::PutImage.new(
+end
-    X11::Form::ZPixmap, wid, $gc2, $png.width, $png.height, 80, 80, 0, depth, data))
+
+#$f = Font.load("/usr/share/fonts/truetype/tlwg/Umpush-BoldOblique.ttf")
+$f = Font.load("/usr/share/fonts/truetype/tlwg/Garuda.ttf")
+#$f = Font.load("resources/FiraGO-Regular.ttf")
+
+$sft = SFT.new($f)
+$sft.x_scale = 15
+$sft.y_scale = 15
+$glyphcache = {}
+def render_glyph(display, wid, x,y, ch)
+  gid = $sft.lookup(ch.ord)
+  mtx = $sft.gmetrics(gid)
+  data = $glyphcache[gid]
+  if !data
+    img = Image.new(mtx.min_width, mtx.min_height) #(mtx .min_width + 3) & ~3, mtx.min_height)
+    if !$sft.render(gid, img)
+      raise "Unable to render #{gid}\n"
+    end
+ #   p img
+    data = img.pixels.map {|px|
+      "\0\0"+px.chr+"\0" #+ "\0\0\0"
+    }.join.force_encoding("ASCII-8BIT")
+    $glyphcache[gid] = data
+  end
+  depth = 24
+#  p data
+#p img
+#  p ch
+ display.put_image(
+    X11::Form::ZPixmap, wid, $gc2,
+    mtx.min_width,mtx.min_height,
+    x, y - mtx.y_offset, 0, depth, data
+  )
+  mtx.advance_width
+end
+
+def render_str(display, wid, x,y, str)
+  str.each_byte do |ch|
+    off = render_glyph(display, wid, x, y, ch.chr)
+    x+= off
+  end
+end
+
+def redraw(dpy, wid, gc)
+  dpy.poly_fill_rectangle(wid, gc, [X11::Form::Rectangle.new(20,20, 60, 80)])
+  dpy.clear_area(false, wid, 30, 30, 5, 5)
+  dpy.image_text16(wid, $gc2, 30, 70, "ΑΒΓΔΕΖΗΘΙΚΛΜΝΞΟΠΡΣΤΥΦΧΨΩ")
+  #"\u25f0\u25ef Hello World")
+  dpy.put_image(
+    X11::Form::ZPixmap, wid, $gc2,
+    $png.width, $png.height, 80, 120, 0, 24, $data
+  )
+  render_str(dpy, wid, 30,90, 'HelloWorld')
 end
 
 loop do
@@ -104,5 +174,9 @@ loop do
   if pkt
     p pkt
     redraw(display, wid, gc) if pkt.is_a?(X11::Form::Expose)
+
+    if pkt.is_a?(X11::Form::KeyPress)
+      lookup_keysym(dpy,pkt)
+    end
   end
 end