dimitri/lsystems
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Add new instruction: draw forward without drawing a line

Browse source
This commit is contained in:
Dimitri Lozeve 2018-02-01 22:05:45 +00:00
parent 217ebcf8f6
commit 61fd4963f1
2 changed files with 31 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

27
examples/cantor.json Normal file
View file

@ -0,0 +1,27 @@
{
"name": "cantor",
"alphabet": "AB",
"axiom": "A",
"rules": [
[
"A",
"ABA"
],
[
"B",
"BBB"
]
],
"angle": 60.0,
"distance": 10.0,
"representation": [
[
"A",
"Forward"
],
[
"B",
"ForwardNoDraw"
]
]
}

4
src/Lib.hs
View file

@ -43,6 +43,7 @@ instance (ToJSON a) => ToJSON (LSystem a) where
-- | Instructions for displaying the L-system -- | Instructions for displaying the L-system
data Instruction = data Instruction =
Forward -- ^ move forward Forward -- ^ move forward
| ForwardNoDraw -- ^ move forward, do not draw a line
| TurnRight -- ^ turn right by angle | TurnRight -- ^ turn right by angle
| TurnLeft -- ^ turn left by angle | TurnLeft -- ^ turn left by angle
| Push -- ^ push a position on the stack | Push -- ^ push a position on the stack
@ -54,6 +55,8 @@ instance FromJSON Instruction where
parseJSON = withText "Instruction" $ \s -> parseJSON = withText "Instruction" $ \s ->
if s `elem` ["Forward", "forward", "F", "f"] then if s `elem` ["Forward", "forward", "F", "f"] then
pure Forward pure Forward
else if s `elem` ["ForwardNoDraw", "forwardnodraw", "FN", "fn"] then
pure ForwardNoDraw
else if s `elem` ["TurnRight", "Turnright", "turnright", "Right", "right", "R", "r"] then else if s `elem` ["TurnRight", "Turnright", "turnright", "Right", "right", "R", "r"] then
pure TurnRight pure TurnRight
else if s `elem` ["TurnLeft", "Turnleft", "turnleft", "Left", "left", "L", "l"] then else if s `elem` ["TurnLeft", "Turnleft", "turnleft", "Left", "left", "L", "l"] then
@ -94,6 +97,7 @@ turtle angle distance = go 90 (Line [(0,0)]) (Pictures []) []
go theta (Line path) (Pictures ps) stack (x:xs) = go theta (Line path) (Pictures ps) stack (x:xs) =
case x of case x of
Forward -> go theta (Line (p:path)) (Pictures ps) stack xs Forward -> go theta (Line (p:path)) (Pictures ps) stack xs
ForwardNoDraw -> go theta (Line [p]) (Pictures (Line path : ps)) stack xs
TurnRight -> go (theta + angle) (Line path) (Pictures ps) stack xs TurnRight -> go (theta + angle) (Line path) (Pictures ps) stack xs
TurnLeft -> go (theta - angle) (Line path) (Pictures ps) stack xs TurnLeft -> go (theta - angle) (Line path) (Pictures ps) stack xs
Push -> go theta (Line path) (Pictures ps) ((head path, theta):stack) xs Push -> go theta (Line path) (Pictures ps) ((head path, theta):stack) xs