arrows.rb in ctioga2-0.12

- old
+ new

@@ -33,11 +33,16 @@
           typed_attribute "#{e}_scale".to_sym, 'float'
           typed_attribute "#{e}_angle".to_sym, 'float'
           typed_attribute "#{e}_color".to_sym, 'color'
         end
 
-        def draw_arrow(t, x1, y1, x2, y2)
+        TiogaDefaults = {
+          'head_marker' => Tioga::MarkerConstants::Arrowhead,
+          'tail_marker' => Tioga::MarkerConstants::BarThin
+        }
+
+        def old_draw_arrow(t, x1, y1, x2, y2)
           dict = self.to_hash
           dict.rename_key('width', 'line_width')
           dict.rename_key('style', 'line_style')
           dict['head'] = [x2,y2]
           dict['tail'] = [x1,y1]
@@ -47,10 +52,145 @@
             end
           end
           t.show_arrow(dict)
         end
 
+
+        # Draws an arrow.
+        def draw_arrow(t, x1, y1, x2, y2)
+          dx = x2 - x1
+          dy = y2 - y1
+
+          angle = Types::Dimension.get_angle(t, dx, dy)
+
+          len = Types::Dimension.get_distance(t, dx, dy)
+
+          rs = symbol_size(t, "head")
+          ls = symbol_size(t, "tail")
+
+          x1n, y1n, x2n, y2n = *Types::Dimension::adjust_line(t, x1, y1, x2, y2, -ls, -rs)
+
+          # Must shorten the path first...
+          sv = t.line_cap
+          
+          # This has for effect to disable changing the line cap when
+          # there are now arrows to draw.
+          if ! (has_marker?('head') || has_marker?('tail'))
+            sv = Tioga::FigureConstants::LINE_CAP_BUTT
+          end
+          if sv != Tioga::FigureConstants::LINE_CAP_BUTT
+            t.line_cap = Tioga::FigureConstants::LINE_CAP_BUTT
+          end
+          draw_line(t, x1n, y1n, x2n, y2n)
+          if sv != Tioga::FigureConstants::LINE_CAP_BUTT
+            t.line_cap = sv
+          end
+
+          # Then, draw the arrow heads/tails
+          draw_symbol(t, 'head', angle, x2, y2)
+          draw_symbol(t, 'tail', angle - 180, x1, y1)
+          
+        end
+
+        protected
+
+        # Return the dimension of the arrow size
+        def symbol_size(t, name)
+          sz = Types::Dimension.new(:dy,self.send("#{name}_scale") || 1.0)
+          sz.value *= case just(name)
+                     when Tioga::FigureConstants::CENTERED
+                       0
+                     when Tioga::FigureConstants::RIGHT_JUSTIFIED
+                       0.5
+                     end
+          return sz
+        end
+
+        def just(name)
+          mkr = self.send("#{name}_marker")
+          if mkr == Tioga::MarkerConstants::Arrowhead or
+            mkr == Tioga::MarkerConstants::ArrowheadOpen
+            Tioga::FigureConstants::RIGHT_JUSTIFIED
+          else
+            Tioga::FigureConstants::CENTERED
+          end
+        end
+
+        def has_marker?(name)
+          mkr = self.send("#{name}_marker")
+          if ! mkr  or  mkr == 'None'
+            return false
+          else
+            return true
+          end
+        end
+
+        # Draw the arrow symbol for the given name (head or tail),
+        # with the given base angle and at the given position
+        def draw_symbol(t, name, angle, x, y)
+          hsh = {}
+          for k in %w(marker scale color angle)
+            tmp = self.send("#{name}_#{k}")
+            if tmp
+              hsh[k] = tmp
+            end
+          end
+          mkr = hsh['marker']
+          if ! mkr  or  mkr == 'None'
+            return
+          end
+
+          hsh['angle'] ||= 0
+          hsh['angle'] += angle
+
+          hsh['x'] = x
+          hsh['y'] = y
+
+          # Color defaults to line color
+          if @color and !hsh.key?('color')
+            hsh['color'] = @color
+          end
+
+          hsh['justification'] = just(name)
+          t.show_marker(hsh)
+        end
+
       end
+
+      # This class represents all the stylistic information necessary
+      # to draw a line parallel to a certain direction, indicated by
+      # an angle (default to horizontal)
+      class OrientedLineStyle < ArrowStyle
+        # The angle, in degrees.
+        typed_attribute :angle, 'float'
+
+        # The alignment of the line with respect to the point given.
+        typed_attribute :origin, 'justification'
+
+        # len is a dimension
+        def draw_oriented_arrow(t, xo, yo, len)
+
+          angle = @angle || 0.0
+
+          dx,dy = *len.to_figure(t, angle)
+
+          case @origin || Tioga::FigureConstants::LEFT_JUSTIFIED
+          when Tioga::FigureConstants::LEFT_JUSTIFIED
+            x1, y1 = xo, yo
+            x2, y2 = xo + dx, yo + dy
+          when Tioga::FigureConstants::CENTERED
+            x1, y1 = xo - 0.5 * dx, yo - 0.5 * dy
+            x2, y2 = xo + 0.5 * dx, yo + 0.5 * dy
+          when Tioga::FigureConstants::RIGHT_JUSTIFIED
+            x1, y1 = xo - dx, yo - dy
+            x2, y2 = xo, yo
+          end
+          
+          draw_arrow(t, x1, y1, x2, y2)
+        end
+        
+      end
+
     end
   end
 end
 