refactoring to get middle/center, possibly more

docs/args/wh.rst

@@ -9,4 +9,4 @@ width
 height
   default: ``:deck`` (the height of the deck)
 
-  the height of the box. Supports :doc:`/units`.
+  the height of the box. Supports :doc:`/units`. Also can be ``:center`` or ``:middle`` for half the height of the deck. Supports :doc:`/units`.

docs/args/xywhbox.rst

@@ -0,0 +1,16 @@
+.. :orphan:
+
+x
+  default: ``0``
+
+  the x-coordinate to place, relative to the upper-left corner of the card and moving right as it increases. Supports :doc:`/units`.
+
+  Also can be ``:center`` or ``:middle`` for half the width of the deck.
+
+
+y
+  default: ``0``
+
+  the y-coordinate to place, relative to the upper-left corner of the card and moving downward as it increases. Supports :doc:`/units`.
+
+  Also can be ``:center`` or ``:middle`` for half the height of the deck.

lib/squib/args/box.rb

@@ -1,17 +1,20 @@
 require_relative 'arg_loader'
+require_relative 'xywh_shorthands'
 
 module Squib::Args
 
   module_function def extract_box(opts, deck, dsl_method_defaults = {})
-    Box.new(deck, dsl_method_defaults).extract!(opts, deck)
+    Box.new(deck, dsl_method_defaults, opts).extract!(opts, deck)
   end
 
   class Box
     include ArgLoader
+    include XYWHShorthands
 
-    def initialize(deck = nil, dsl_method_defaults = {})
+    def initialize(deck = nil, dsl_method_defaults = {}, opts = {})
       @deck = deck
       @dsl_method_defaults = dsl_method_defaults
+      @opts = opts # e.g. value of x can depend on the value of width
     end
 
     def self.parameters
@@ -29,16 +32,22 @@ module Squib::Args
       parameters.keys # all of them
     end
 
+    def validate_x(arg, i)
+      apply_x_shorthands(arg, @deck.width)
+    end
+
+    def validate_y(arg,_i)
+      apply_y_shorthands(arg, @deck.height)
+    end
+
     def validate_width(arg, _i)
       return arg if @deck.nil?
-      return @deck.width if arg == :deck
-      arg
+      apply_x_shorthands(arg, @deck.width)
     end
 
     def validate_height(arg, _i)
       return arg if @deck.nil?
-      return @deck.height if arg == :deck
-      arg
+      apply_y_shorthands(arg, @deck.height)
     end
 
     def validate_x_radius(arg, i)
@@ -49,7 +58,7 @@ module Squib::Args
     def validate_y_radius(arg, i)
       return radius[i] unless radius[i].nil?
       arg
-    end
+    end   
 
   end
 

lib/squib/args/unit_conversion.rb

@@ -13,6 +13,8 @@ module Squib
           arg.rstrip[0..-2].to_f * dpi * INCHES_IN_CM
         when /mm$/ # ends with "mm"
           arg.rstrip[0..-2].to_f * dpi * INCHES_IN_CM / 10.0
+        when /deg$/ # ends with "deg"
+          arg.rstrip[0..-3].to_f * (Math::PI / 180.0)
         else
           arg
         end

lib/squib/args/xywh_shorthands.rb

@@ -0,0 +1,35 @@
+module Squib
+  module Args
+    module XYWHShorthands
+
+      def apply_x_shorthands(arg, deck_width)
+        arg_s = arg.to_s
+        case arg_s
+        when 'middle'
+          deck_width / 2.0
+        when 'center'
+          deck_width / 2.0
+        when 'deck'
+          deck_width
+        else 
+          arg
+        end
+      end
+
+      def apply_y_shorthands(arg, deck_height)
+        arg_s = arg.to_s
+        case arg_s
+        when 'middle'
+          deck_height / 2.0
+        when 'center'
+          deck_height / 2.0
+        when 'deck'
+          deck_height
+        else 
+          arg
+        end
+      end
+
+    end
+  end
+end

lib/squib/dsl/units.rb

@@ -23,5 +23,10 @@ module Squib
       @dpi * Squib::INCHES_IN_CM * n.to_f / 10.0
     end
 
+    # DSL method. See http://squib.readthedocs.io
+    def deg(n)
+      n.to_f * (Math::PI / 180.0)
+    end
+
   end
 end

lib/squib/layout_parser.rb

@@ -1,9 +1,11 @@
 require 'yaml'
+require_relative 'args/xywh_shorthands'
 
 module Squib
   # Internal class for handling layouts
   # @api private
   class LayoutParser
+    include Args::XYWHShorthands
 
     def initialize(dpi = 300)
       @dpi = dpi
@@ -67,6 +69,9 @@ module Squib
     end
 
     def handle_relative_operators(parent_val, child_val)
+      unless has_digits?(parent_val) && has_digits?(child_val)
+        raise "Layout parse error: can't combine #{parent_val} and #{child_val}"
+      end
       if child_val.to_s.strip.start_with?('+=')
         add_parent_child(parent_val, child_val)
       elsif child_val.to_s.strip.start_with?('-=')
@@ -104,6 +109,13 @@ module Squib
       parent_pixels / child_float
     end
 
+    # For relative operators, it's difficult for us to handle 
+    # some of the shorthands - so let's just freak out if you're trying to use 
+    # relative operators with words, e.g. "middle += 0.5in"
+    def has_digits?(str)
+      str.match? /.*\d.*/
+    end
+
     # Does this layout entry have an extends field?
     # i.e. is it a base-case or will it need recursion?
     # :nodoc:

samples/shorthands/_shorthands.rb

@@ -0,0 +1,30 @@
+require_relative '../../lib/squib'
+
+# Lots of DSL methods have shorthands that are accepted for 
+# x, y, width, and height parameters. 
+Squib::Deck.new(width: '0.5in', height: '0.25in') do
+  background color: :white
+
+  text str: 'xymiddle', font: 'Sans Bold 3', hint: :red, 
+       x: 'middle', y: :middle
+       
+  # 'center' also works
+  rect width: 30, height: 30, 
+       x: :center, y: 'center'
+
+  # Layouts apply this too.
+  use_layout file: 'shorthands.yml'
+  rect layout: :example
+
+  # The x and y coordinates can also be "centered", assuming the 
+
+  # HOWEVER! Shorthands don't combine in an "extends" situation, 
+  # e.g. this won't work: 
+  # parent:
+  #   x: middle 
+  # child: 
+  #   extends: parent 
+  #   x: += 0.5in
+
+  save_png prefix: 'shorthand_'
+end

samples/shorthands/shorthands.yml

@@ -0,0 +1,7 @@
+example: 
+  x: 0.15in
+  y: middle
+  stroke_color: blue
+  width: 30
+  height: 30
+

samples/units/_units.rb

@@ -23,10 +23,15 @@ Squib::Deck.new(width: '1.5in', height: '1.5in') do
   	   width: safe_width, height: safe_height,
        radius: '2 mm '
 
+  # Angles are also automatically converted to radians if you use deg
+  svg file: '../spanner.svg',
+      x: 100, y: 100, width: 40, height: 40, angle: '30deg'
+
   # We can also do stuff in layout. Check out the yml file...
   #  (even cleaner in Yaml since we don't need quotes!)
   use_layout file: 'using_units.yml'
   text str: 'Hello.', layout: :example
+  svg file: '../spanner.svg', layout: :angled
 
   save prefix: 'units_', format: :png
 end

samples/units/using_units.yml

@@ -8,3 +8,10 @@ example:
   y: -= 5mm
   width: 1.25in
   height: 300   # pixels
+
+angled:
+  x: 220
+  y: 300
+  width: 30
+  height: 30
+  angle: 100deg

spec/args/box_spec.rb

@@ -122,6 +122,19 @@ describe Squib::Args::Box do
       expect(box).to have_attributes(x_radius: [3], y_radius: [3])
     end
 
+    it 'listens to middle' do 
+      args = { width: :middle, height: 'middle' }
+      box = Squib::Args::Box.new
+      box.extract! args, deck
+      expect(box).to have_attributes(width: [61.5], height: [228.0])
+    end
+    it 'listens to center' do 
+      args = { width: 'center', height: :center }
+      box = Squib::Args::Box.new
+      box.extract! args, deck
+      expect(box).to have_attributes(width: [61.5], height: [228.0])
+    end
+
   end
 
 

spec/args/unit_conversion_spec.rb

@@ -30,5 +30,9 @@ describe Squib::Args::UnitConversion do
     expect(subject.parse('1mm  ')).to eq(11.81102361)
   end
 
+  it 'does deg' do
+    expect(subject.parse('30deg')).to be_within(0.0001).of(0.523599)
+  end
+
 
 end

spec/data/samples/units/_units.rb.txt

@@ -36,6 +36,17 @@ cairo: stroke([])
 cairo: restore([])
 cairo: save([])
 cairo: new_path([])
+cairo: translate([100, 100])
+cairo: transform([Matrix])
+cairo: rotate([0.5235987755982988])
+cairo: scale([0.3125, 0.3125])
+cairo: rounded_rectangle([0, 0, 128.0, 128.0, 0, 0])
+cairo: clip([])
+cairo: translate([0, 0])
+cairo: render_rsvg_handle([Rsvg::Handlenil}])
+cairo: restore([])
+cairo: save([])
+cairo: new_path([])
 cairo: set_source_color(["black"])
 cairo: translate([134.05511805, 166.24488195])
 cairo: rotate([0])
@@ -54,5 +65,16 @@ cairo: show_pango_layout([MockDouble])
 pango: ellipsized?([])
 pango: ellipsized?([])
 cairo: restore([])
+cairo: save([])
+cairo: new_path([])
+cairo: translate([220, 300])
+cairo: transform([Matrix])
+cairo: rotate([1.7453292519943295])
+cairo: scale([0.234375, 0.234375])
+cairo: rounded_rectangle([0, 0, 128.0, 128.0, 0, 0])
+cairo: clip([])
+cairo: translate([0, 0])
+cairo: render_rsvg_handle([Rsvg::Handlenil}])
+cairo: restore([])
 surface: write_to_png(["_output/units_00.png"])
 surface: finish([])