simple area graph

Author: v0dro

.gitignore

@@ -59,3 +59,5 @@ g++
 gcc
 mpicc
 mpicxx
+examples/rect.png
+examples/gr_wrapper/*.png

examples/gr_wrapper/polygon.rb

@@ -0,0 +1,11 @@
+# Filled polygon GR example.
+
+require_relative '../../lib/grruby.so'
+
+Rubyplot::GR.beginprint("polygon.png")
+Rubyplot::GR.setviewport(0,1,0,1)
+Rubyplot::GR.setwindow(0,100,0,100)
+Rubyplot::GR.setfillintstyle(1)
+Rubyplot::GR.settransparency(0.5)
+Rubyplot::GR.fillarea([1, 5, 25, 30, 50, 30], [1, 5, 25, 30, 25, 5])
+Rubyplot::GR.endprint

ext/grruby/grruby.c

@@ -244,6 +244,22 @@ static VALUE inqtext(VALUE self,VALUE a,VALUE b,VALUE c,VALUE d,VALUE e) {
   return Qtrue;
 }
 
+/**
+ * call-seq:
+ *   Rubyplot::GR.fillarea([1,2,3], [1,2,3]) -> true
+ *  
+ * Allows you to specify a polygonal shape of an area to be filled.
+ * 
+ * **Parameters:**
+ * 
+ * `x` :
+ * A list containing the X coordinates
+ * `y` :
+ * A list containing the Y coordinates
+ * 
+ * The attributes that control the appearance of fill areas are fill area interior
+ * style, fill area style index and fill area color index.
+ */
 static VALUE fillarea(VALUE self,VALUE x, VALUE y){
   int x_size = RARRAY_LEN(x);
   int y_size = RARRAY_LEN(y);
@@ -1720,9 +1736,21 @@ static VALUE setshadow(VALUE self,VALUE offsetx,VALUE offsety,VALUE blur){
   return Qtrue;
 }
 
+
+/**
+ * call-seq:
+ *   Rubyplot::GR.settransparency(alpha) -> true
+ *
+ * Set the value of the alpha component associated with GR colors
+ * 
+ * **Parameters:**
+ * 
+ * `alpha` :
+ * An alpha value (0.0 - 1.0)
+ */
 static VALUE settransparency(VALUE self,VALUE alpha){
-  double alphac = NUM2DBL(alpha);
-  gr_settransparency(alphac);
+  gr_settransparency(NUM2DBL(alpha));
+  
   return Qtrue;
 }
 

lib/rubyplot/artist/plot/area.rb

@@ -2,31 +2,25 @@ module Rubyplot
   module Artist
     module Plot
       class Area < Artist::Plot::Base
-        attr_accessor :sorted_data
+        attr_accessor :sort_data
 
         def initialize(*)
           super
-          @sorted_data = true
+          @sort_data = true
         end
 
         def data x_values, y_values=[]
           y_values = Array.new(x_values.size) { |i| i } if y_values.empty?
-          x_values.sort! if @sorted_data
+          x_values.sort! if @sort_data
           super(x_values, y_values)
         end
 
         def draw
-          poly_points = []
-          @normalized_data[:y_values].each_with_index do |iy, idx_y|
-            ix = @normalized_data[:x_values][idx_y]
-            abs_x = ix * @axes.x_axis.length + @axes.origin[0]
-            abs_y = iy * @axes.y_axis.length + @axes.origin[1]
-            poly_points << [abs_x, abs_y]
-          end
-          poly_points << [@axes.x_axis.abs_x2, @axes.origin[1] - @axes.x_axis.stroke_width]
-          poly_points << [@axes.origin[0], @axes.origin[1] - @axes.x_axis.stroke_width]
+          x_poly_points = @data[:x_values].concat([@axes.x_axis.max_val, @axes.x_axis.min_val])
+          y_poly_points = @data[:y_values].concat([@axes.y_axis.min_val, @axes.y_axis.min_val])
           Rubyplot::Artist::Polygon.new(
-            coords: poly_points,
+            x: x_poly_points,
+            y: y_poly_points,
             color: @data[:color],
             fill_opacity: 0.3
           ).draw

lib/rubyplot/artist/polygon.rb

@@ -1,16 +1,18 @@
 module Rubyplot
   module Artist
     class Polygon < Base
-      def initialize(coords:, fill_opacity: 1.0, color: :default, stroke: 'transparent')
-        @coords = coords
+      def initialize(x:, y:, fill_opacity: 1.0, color: :default, stroke: 'transparent')
+        @x = x
+        @y = y
         @fill_opacity = fill_opacity
         @color = color
         @stroke = stroke
       end
 
       def draw
         Rubyplot.backend.draw_polygon(
-          coords: @coords,
+          x: @x,
+          y: @y,
           border_color: @color,
           border_width: 1.0,
           border_type: :solid,

lib/rubyplot/backend/base.rb

@@ -48,17 +48,18 @@ def draw_markers(x:, y:, marker_type:, marker_color:, marker_size:)
         raise NotImplementedError, "not implemented for #{self}."
       end
 
-      # Draw a circle.
+      # Draw a circle.n
       def draw_circle(x:, y:, radius:, border_color:, fill_color:, border_width:)
         raise NotImplementedError, "not implemented for #{self}."
       end
 
       # Draw a polygon and fill it with color. Co-ordinates are specified in (x,y)
       # pairs in the coords Array.
       #
-      # @param coords [Array] Array containing pairs of co-ordinates in (x,y) pairs.
+      # @param x [Array] Array containing X co-ordinates.
+      # @param y [Array] Array containting Y co-ordinates.
       # @param border_width [Numeric] Widht of the border.
-      def draw_polygon(coords:, border_width:, border_type:, border_color:, fill_color:,
+      def draw_polygon(x:, y:, border_width:, border_type:, border_color:, fill_color:,
         fill_opacity:)
       end
     end # class Base

lib/rubyplot/backend/gr_wrapper.rb

@@ -188,8 +188,18 @@ def draw_lines(x:, y:, width:, type:, color:)
         end
       end
 
-      def draw_polygon(coords:, border_width:, border_type:, border_color:, fill_color:,
+      def draw_polygon(x:, y:, border_width:, border_type:, border_color:, fill_color:,
         fill_opacity:)
+        within_window do
+          draw_lines(x: x, y: y, width: border_width, color: border_color,
+            type: border_type)
+          if fill_color
+            GR.settransparency(fill_opacity)
+            GR.setfillintstyle(1)
+            GR.setfillcolorind(to_gr_color(fill_color))
+            GR.fillarea(x, y)
+          end
+        end
       end
 
       # Draw text on the canvas. Unlike other functions, this function does not
@@ -342,7 +352,7 @@ def within_window(abs=false, &block)
             @active_axes.x_range[1],
             @active_axes.y_range[0],
             @active_axes.y_range[1]
-          )          
+          )
         end
 
         block.call
@@ -353,6 +363,7 @@ def draw_axes
           axes = v[:axes]
           tick_length = transform_avg_ndc(axes.x_axis.major_ticks[0].length)
           within_window do
+            GR.settransparency(1)
             GR.setcharheight(0.018)
             GR.setlinecolorind(to_gr_color(:black))
             GR.axes(

spec/axes_spec.rb

@@ -119,7 +119,6 @@
         p.label = "Jimmy"
       end
       axes.title = "Visual simple area graph test."
-      axes.num_x_ticks = 5
       axes.x_ticks = ['0', '22', '44', '66', '88']
     end