turtle documentation, and some little "API" change

Fela Winkelmolen · Fela Winkelmolen · commit 623abbaf919b · 2010-07-06T23:34:24.000+02:00
diff --git a/h-ety-h/turtlescript.rb b/h-ety-h/turtlescript.rb
@@ -2,8 +2,8 @@
 
 class Shoes::TurtleCanvas < Shoes::Widget
   # default values
-  WIDTH = 400
-  HEIGHT = 400
+  WIDTH = 500
+  HEIGHT = 500
   SPEED = 4 # power of two
   
   include Math
@@ -12,6 +12,7 @@ class Shoes::TurtleCanvas < Shoes::Widget
   # para with the next command written on it
   attr_writer :next_command, :pen_info
   attr_accessor :speed # powers of two
+  attr_reader :width, :height
 
   def initialize
     @width = WIDTH
@@ -87,15 +88,15 @@ def pendown
     is_step
     @pendown = true
   end
-  def isdown?
+  def pendown?
     return @pendown
   end
-  def go x, y
+  def goto x, y
     is_step
     update_position(x, y)
   end
   def center
-    go(200, 200)
+    go(width/2, height/2)
   end
   def setx x
     is_step
@@ -115,7 +116,9 @@ def getposition
     [@x, @y]
   end
   def getheading
-    @heading
+    degs = @heading/DEG
+    degs += 180
+    degs % 360
   end
 
   ### user commands already in shoes (the first two with another name ###
diff --git a/samples/turtle_barbwire.rb b/samples/turtle_barbwire.rb
@@ -5,7 +5,7 @@
   background yellow
   pencolor brown
   pensize 2
-  go 30, 200
+  goto 30, 200
   setheading 180
   1000.times do
     forward 20
diff --git a/samples/turtle_stars.rb b/samples/turtle_stars.rb
@@ -5,12 +5,12 @@
   pensize 2
   pencolor yellow
   30.times do
-    go rand(400), rand(400)
+    goto rand(width), rand(height)
     setheading rand(360)
     len = 5 + rand(30)
     5.times do
       forward len
       turnleft 180-360/10
     end
   end
-end
+end
diff --git a/turtle-graphics b/turtle-graphics
@@ -0,0 +1,79 @@
+Turtle Graphics support (http://en.wikipedia.org/wiki/Turtle_graphics)
+
+Turtle code can be run from the HacketyHack editor, two modes are available:
+
+1. interactive mode, allowing step by step execution
+
+Turtle.start do
+  # turtle code here
+end
+
+
+2. drawing mode that execute the whole code at once
+
+Turtle.draw do
+  # turtle code here
+end
+
+
+== Available Commands ==
+penup
+after this command gets called the pen is up and nothing is drawn
+
+pendown
+after this command the pen is dawn and lines are drawn as the turtle moves
+
+pendown?
+returns true if the pen is down, (default is true)
+
+pensize x
+set the width of the line drawn by the turtle to x
+
+pencolor c
+set the color of the line drawn by the turtle to c, use the shoes color system
+
+background c
+set the background color to c, use the shoes color system
+
+forward x
+moves the turtle forward by x pixels
+when no options are given a default argument of 50 pixels is used
+
+backward x
+moves the turtle forward by x pixels, equivalent to forward -x
+when no options are given a default argument of 50 pixels is used
+
+turnleft a
+turns the turtle heading a degrees to the left, default heading is 0 degrees
+when no options are given a default argument of 90 degrees is used
+
+turnright a
+turns the turtle heading a degrees to the right, equivalent to turnleft -a
+when no options are given a default argument of 90 degrees is used
+
+setheading a
+sets the current heading to a
+
+getheading
+retuns the current heading in degrees
+
+setx x
+moves the turtle horizontally to (current_y, x)
+doesn't draw anything
+
+sety y
+moves the turtle vertically to (y, current_x)
+doesn't draw anything
+
+goto x, y
+moves the turtle to (x, y)
+doesn't draw anything
+
+getposition
+retuns [x, y] (as an array)
+
+clear
+removes all content (but does not change the turtle attributes)
+
+reset
+removes all content and resets all attributes (including turtle position)
