pencelab

a    b    cc     dd     e e   
    bb   ccc    ddd    eeee   
         ccc    ddd   eeeee   
               dddd    eeee   
                      eeeee   

pencelab

z*aa    y  * bb b    x   *  ccc cc     w     *   dddd  dd     v      *    eeeee  e e   
        y ***bbbb   xxx *** cccccc    www   ***  dddd ddd    vvv    ***   eeeee eeee   
                     x *****cccccc    www  ***** dddd ddd   vvvvv  *****  eeeeeeeeee   
                                       w  *******dddddddd    vvv  ******* eeeee eeee   
                                                              v  *********eeeeeeeeee   

pencelab

panel {
    repeat(5) {
        composed {
            val rhombus = rhombus {
                lines = it + 1
                char = 'z' - it
            }
            val triangle = triangle {
                lines = it + 1
            }

pencelab

    a       bbbbb   ccccc     d     eeeee        
   aaa      bbbbb   ccccc    ddd    eeeee      d 
  aaaaa     bbbbb   ccccc   ddddd   eeeee     ddd
 aaaaaaa    bbbbb   ccccc    ddd    eeeee    ddd 
aaaaaaaaa   bbbbb   ccccc     d     eeeee     d  

pencelab

panel {
    val shapes = mutableListOf<Shape>()
    
    repeat(5) {
        shapes.add(when ((1..3).random()) {
            1 -> square {
                lines = 5
                char = 'a' + it
            }
            2 -> triangle {

pencelab

a    b      c        d          e            f              g                h                  i                    j            
    bbb    ccc      ddd        eee          fff            ggg              hhh                iii                  jjj           
          ccccc    ddddd      eeeee        fffff          ggggg            hhhhh              iiiii                jjjjj          
                  ddddddd    eeeeeee      fffffff        ggggggg          hhhhhhh            iiiiiii              jjjjjjj         
                            eeeeeeeee    fffffffff      ggggggggg        hhhhhhhhh          iiiiiiiii            jjjjjjjjj        
                                        fffffffffff    ggggggggggg      hhhhhhhhhhh        iiiiiiiiiii          jjjjjjjjjjj       
                                                      ggggggggggggg    hhhhhhhhhhhhh      iiiiiiiiiiiii        jjjjjjjjjjjjj      
                                                                      hhhhhhhhhhhhhhh    iiiiiiiiiiiiiii   

pencelab

panel {
        
    for (i in 0..9) {
        triangle {
            lines = i + 1
            char = 'a' + i
        }
        space()
    }

pencelab

inline fun panel(init: (@ShapeDsl Panel).() -> Unit): Panel {
    return Panel().apply { init() }
}

inline fun Panel.square(init: SquareBuilder.() -> Unit): Square {
    return SquareBuilder().apply { init() }.build().also { this.addShape(it) }
}

inline fun Panel.triangle(init: TriangleBuilder.() -> Unit): Triangle {
    return TriangleBuilder().apply { init() }.build().also { this.addShape(it) }

pencelab

panel {
    square {
        lines = 8
        char = 'd'

        this@panel.triangle {
            lines = 10
            char = 'x'
        }
    }

pencelab

@ShapeDsl
abstract class ShapeBuilder {

    private companion object {
        const val DEFAULT_CHAR = '*'
    }

    var char = DEFAULT_CHAR
    var lines = 0