Copyright | (c) Archibald Neil MacDonald 2020 |
---|---|
License | BSD3 |
Maintainer | FortOyer@hotmail.co.uk |
Stability | experimental |
Portability | POSIX |
Safe Haskell | None |
Language | Haskell2010 |
This module is a collection of all the commands used to manipulate a turtle!
Synopsis
- data Turtle
- makeTurtle :: TurtleCommand Turtle
- makeTurtle' :: Point -> Float -> Color -> TurtleCommand Turtle
- type Point = (Float, Float)
- forward :: Float -> Turtle -> TurtleCommand ()
- fd :: Float -> Turtle -> TurtleCommand ()
- backward :: Float -> Turtle -> TurtleCommand ()
- bk :: Float -> Turtle -> TurtleCommand ()
- left :: Float -> Turtle -> TurtleCommand ()
- lt :: Float -> Turtle -> TurtleCommand ()
- right :: Float -> Turtle -> TurtleCommand ()
- rt :: Float -> Turtle -> TurtleCommand ()
- circle :: Float -> Float -> Turtle -> TurtleCommand ()
- goto :: Point -> Turtle -> TurtleCommand ()
- setPosition :: Point -> Turtle -> TurtleCommand ()
- home :: Turtle -> TurtleCommand ()
- setHeading :: Float -> Turtle -> TurtleCommand ()
- setSpeed :: Float -> Turtle -> TurtleCommand ()
- stamp :: Turtle -> TurtleCommand ()
- representation :: Turtle -> TurtleCommand Picture
- position :: Turtle -> TurtleCommand Point
- heading :: Turtle -> TurtleCommand Float
- speed :: Turtle -> TurtleCommand Float
- penColor :: Turtle -> TurtleCommand Color
- penDown :: Turtle -> TurtleCommand Bool
- penSize :: Turtle -> TurtleCommand Float
- visible :: Turtle -> TurtleCommand Bool
- setPenColor :: Color -> Turtle -> TurtleCommand ()
- setPenDown :: Bool -> Turtle -> TurtleCommand ()
- setPenSize :: Float -> Turtle -> TurtleCommand ()
- setRepresentation :: Picture -> Turtle -> TurtleCommand ()
- setVisible :: Bool -> Turtle -> TurtleCommand ()
- clear :: TurtleCommand ()
- east :: Float
- north :: Float
- west :: Float
- south :: Float
Setting up a turtle.
The Turtle that is drawn on the canvas! Create a new turtle using
makeTurtle
.
makeTurtle :: TurtleCommand Turtle Source #
Creates a new Turtle
and displays it on the canvas. This turtle can then be
manipulated! For example, to create a turtle and then move the turtle forward:
main:: IO () main = runTurtle $ do t <- makeTurtle forward 90 t
The default turtle starts at position (0, 0) and is orientated North
.
:: Point | Initial position of the turtle. |
-> Float | Initial heading of the turtle. |
-> Color | Color of the turtle and the turtle's pen. |
-> TurtleCommand Turtle | The generated turtle. |
This variant of makeTurtle
takes a starting position, a starting
orientation, and a color to apply to the turtle and the turtle's pen.
myCommand :: TurtleCommand () myCommand = do t1 <- makeTurtle' (0, 0) 0 green t2 <- makeTurtle' (0, 0) 90 red forward 90 t1 <|> forward 90 t2
See makeTurtle
.
Movement commands.
:: Float | Distance to move the turtle. |
-> Turtle | The turtle to move. |
-> TurtleCommand () |
Move the turtle forward by the specified distance
, in the direction the
turtle is headed.
:: Float | Distance to move the turtle. |
-> Turtle | The turtle to move. |
-> TurtleCommand () |
Move the turtle backward by the specified distance
, in the direction the
turtle is headed.
:: Float | Rotation amount to apply to turtle. |
-> Turtle | The turtle to rotate. |
-> TurtleCommand () |
Turn a turtle left by the given degrees amount.
:: Float | Rotation amount to apply to turtle. |
-> Turtle | The turtle to rotate. |
-> TurtleCommand () |
Turn a turtle right by the given degrees amount.
:: Float | Radius of the circle. |
-> Float | Angle to travel in degrees.
For example: |
-> Turtle | Turtle to move in a circle. |
-> TurtleCommand () |
Draw an arc with a given radius
. The center is radius
units left of the
turtle
if positive. Otherwise radius
units right of the turtle
if
negative.
The arc is drawn in an anticlockwise direction if the radius is positive, otherwise, it is drawn in a clockwise direction.
:: Point | Position to warp to. |
-> Turtle | Turtle to modify. |
-> TurtleCommand () |
Warps the turtle to a new position. The turtle jumps to this new position with no animation. If the pen is down then a line is drawn.
setPosition :: Point -> Turtle -> TurtleCommand () Source #
Alias of goto
.
home :: Turtle -> TurtleCommand () Source #
Warps the turtle to its starting position (0, 0)
and resets the
orientation to North
(90 degrees). No line is drawn moving the turtle.
:: Float | Heading to apply. |
-> Turtle | Turtle to set. |
-> TurtleCommand () |
Sets the turtle's heading. See heading
.
:: Float | New speed. |
-> Turtle | Turtle to modify. |
-> TurtleCommand () |
Sets the turtle's speed.
See speed
.
Styling commands.
:: Turtle | The turtle with the shape to be copied. |
-> TurtleCommand () |
Stamp a copy of the turtle shape onto the canvas at the current turtle position.
:: Turtle | Turtle to query. |
-> TurtleCommand Picture |
Gets the turtle's representation as a Gloss Picture
.
Tell turtle's state.
:: Turtle | Turtle to query. |
-> TurtleCommand Point | Returned current point. |
Returns the turtle's current position.
Default (starting) position is (0, 0)
.
:: Turtle | Turtle to query. |
-> TurtleCommand Float | Returned heading as angle in degrees. |
Returns the turtle's heading.
0
is along the positive x-axis, going anticlockwise. So:
- East is
0
degrees. - North is
90
degrees. - West is
180
degrees. - South is
270
degrees.
The default heading is North (90
degrees).
:: Turtle | Turtle to query. |
-> TurtleCommand Float |
Returns whether the turtle's current speed.
Speed is is distance
per second.
A speed of 0 is equivalent to no animation being performed and instant
drawing.
The default value is 200
.
:: Turtle | Turtle to query. |
-> TurtleCommand Color | Returned current pen color. |
Returns the turtle's pen color.
The color of the turtle's pen.The default color is black
.
:: Turtle | Turtle to query. |
-> TurtleCommand Bool | True if pen is down, false if not. |
Returns whether the turtle's pen is down.
When the turtle's pen is down it will draw a line when it moves.
The default value is true
.
:: Turtle | Turtle to query. |
-> TurtleCommand Float | Size of turtle's pen. |
Returns the turtle's pen size.
Defaults to 2
.
:: Turtle | Turtle to query. |
-> TurtleCommand Bool | True if turtle is visible,false if not. |
Returns whether the turtle is visible.
The default value is true
.
Drawing state.
:: Color | New pen color to apply |
-> Turtle | Turtle to modify. |
-> TurtleCommand () |
Set the turtle's pen color.
See penColor
.
:: Bool | New state for pen flag. True for down. False for up. |
-> Turtle | Turtle to modify. |
-> TurtleCommand () |
Sets the turtle's pen to down or up.
See penDown
.
:: Float | New size for turtle's pen. |
-> Turtle | Turtle to modify. |
-> TurtleCommand () |
Sets the turtle's pen size.
See penSize
.
:: Picture | |
-> Turtle | Turtle to mutate. |
-> TurtleCommand () |
Sets the turtle's representation to a Gloss Picture
.
See representation
.
For example, to set the turtle as a red circle:
import Graphics.WorldTurtle import qualified Graphics.Gloss.Data.Picture as G myCommand :: TurtleCommand () myCommand = do t <- makeTurtle setPenColor red t setRepresentation (G.color red $ G.circleSolid 10) t forward 90 t
:: Bool | New state for visible flag. |
-> Turtle | Turtle to modify. |
-> TurtleCommand () |
Sets the turtle's visibility.
See visible
.
Canvas commands.
clear :: TurtleCommand () Source #
Clears all drawings form the canvas. Does not alter any turtle's state.