--- Imports ---


-- Goal --

import Pendulum

import Goal.Core
import Goal.Geometry
import Goal.Simulation


--- Globals ---


qdq0 = fromList (Bundle pndl) [0,0]


--- Main ---


main = do

    let rnbl = toRenderable . execEC $ do

            vectorFieldLayout

            layout_title .= "Pendulum Vector Field"

            plot . fmap plotVectorField . liftEC $ do

                vectorFieldPlot $ opaque red
                plot_vectors_mapf .= sliceVectorField 0.1 0 f qdq0
                plot_vectors_title .= "Damped"

            plot . fmap plotVectorField . liftEC $ do

                vectorFieldPlot $ opaque blue
                plot_vectors_mapf .= sliceVectorField 0.1 0 fg qdq0
                plot_vectors_title .= "Conservative"

    void $ renderableToAspectWindow False 800 800 rnbl
    --void $ renderableToFile (FileOptions (400,400) PDF) "vector-field.pdf" rnbl