LambdaNetFigure.kt

package afield.examples.stdlib

import afield.geometry.path.FLine
import afield.ui.visualization.drawToSVG
import afield.ai.learning.*
import afield.ai.retrieval.*
import afield.animation.interpolation.*
import afield.animation.keyframes.*
import afield.animation.motion.*
import afield.app.commands.*
import afield.app.diagnostics.*
import afield.audio.analysis.*
import afield.audio.synth.*
import afield.data.collections.*
import afield.data.formats.*
import afield.data.graph.*
import afield.data.sorting.*
import afield.document.context.*
import afield.document.graph.*
import afield.document.properties.*
import afield.document.workspace.*
import afield.geometry.mesh.*
import afield.geometry.path.*
import afield.geometry.spatial.*
import afield.graphics.color.*
import afield.graphics.interaction.*
import afield.graphics.render.*
import afield.graphics.shader.*
import afield.graphics.text.*
import afield.graphics.vulkan.buffers.*
import afield.io.osc.*
import afield.io.process.*
import afield.lang.lambda.*
import afield.lang.python.*
import afield.lang.remotejs.*
import afield.lang.stacksl.*
import afield.math.autodiff.*
import afield.math.control.*
import afield.math.estimation.*
import afield.math.functions.*
import afield.math.linalg.*
import afield.math.optimization.*
import afield.math.statistics.*
import afield.math.units.*
import afield.media.image.*
import afield.media.video.*
import afield.runtime.execution.*
import afield.runtime.languages.*
import afield.runtime.lifecycle.*
import afield.simulation.agents.*
import afield.simulation.automata.*
import afield.simulation.particles.*
import afield.study.build.*
import afield.study.evidence.*
import afield.study.search.*
import afield.study.source.*
import afield.study.ui.*
import afield.ui.controls.*
import afield.ui.output.*
import afield.ui.visualization.*
import java.io.File
import kotlin.math.max
import kotlin.math.min

    @JvmStatic
    fun main(args: Array<String>) {
        val target = args.firstOrNull()
        check(target != null) { "usage: LambdaNetFigure <output .svg path>" }

        val term = LambdaTerms.parse(TERM)
        val compiled = LambdaTerms.compile(term)
        // 8 relax iterations per step, unlike the headless default of 0: this one *is* the picture.
        val reducer = Reducer(Lambda.rules(), relaxIterations = 8)

        val stages = ArrayList<Pair<String, String>>()
        compiled.net.relax(iterations = 60)
        stages += "compiled" to snapshotDescription(compiled.net)

        var step = 0
        while (true) {
            val detail = reducer.stepDetailed(compiled.net) ?: break
            step++
            compiled.net.relax(iterations = 24)
            stages += "$step. ${detail.ruleName}" to snapshotDescription(compiled.net)
            check(step < 40) { "Reduction did not settle in 40 steps" }
        }

        val readback = LambdaTerms.readback(compiled)
        val oracle = LambdaTerms.referenceNormalOrder(term)

        // Panels are drawn from the *live* net at each stage, so the net has to be re-reduced once per panel: the
        // reducer mutates in place and there is no snapshotting. Cheap at this size, and it keeps the panels honest
        // about what the reducer actually did rather than reconstructing it.
        val panelLines = ArrayList<FLine>()
        for ((index, stage) in stages.withIndex()) {
            val net = replay(index)
            val x0 = index * (PANEL_WIDTH + GUTTER)
            panelLines += frame(x0)
            panelLines += fit(net, x0)
            check(stage.second.isNotEmpty()) { "empty stage description" }
        }

        val width = stages.size * PANEL_WIDTH + (stages.size - 1) * GUTTER

        // NO BACKGROUND PLATE. This used to prepend an opaque white rectangle over the whole figure,
        // and it was the only one of the 30 committed SVGs under public/docs to paint a background at
        // all -- so on the dark documentation site it showed up as a white slab with the page dark
        // around it. Every sibling figure is transparent and inherits the page, and now so is this.
        // The strokes and discs are pale (#BDEBEE, #C7C5E4, #FFF5E6 and friends), which is why they
        // read fine either way; the plate was never doing any work.
        val svg = drawToSVG(panelLines, width, PANEL_HEIGHT)
        File(target).writeText(svg)

        println("term        : $TERM")
        println("panels      : ${stages.size} (${stages.joinToString(" | ") { it.first }})")
        for ((label, description) in stages) println("  ${label.padEnd(18)} $description")
        println("readback    : ${LambdaTerms.format(readback)}")
        println("oracle      : ${LambdaTerms.format(oracle)}")
        println("agree       : ${LambdaTerms.alphaEquivalent(readback, oracle)}")
        println("wrote       : $target (${File(target).length()} bytes, ${width.toInt()}x${PANEL_HEIGHT.toInt()})")
        check(LambdaTerms.alphaEquivalent(readback, oracle)) { "Figure term did not reduce correctly" }
    }