Start recording Skia frames in SKP files from Kotlin Compose Desktop

Main.kt

fun main() = application {
    Window(onCloseRequest = ::exitApplication) {
        LaunchedEffect(Unit) {
            window.attachSkiaDebugger()
        }
        MaterialTheme {
            Row(
                verticalAlignment = Alignment.CenterVertically,
                modifier = Modifier.background(Color.LightGray).height(IntrinsicSize.Min)
            ) {
                Text(
                    "Text 1",
                    modifier = Modifier.background(Color.Green),
                )
                Text(
                    "Text 2\nMultiline",
                    modifier = Modifier.background(Color.Yellow),
                )

                Text(
                    "Text 3",
                    modifier = Modifier.background(Color.Red),
                )
            }
        }
    }
}

Skia.kt

import androidx.compose.ui.awt.ComposeWindow
import org.jetbrains.skia.Canvas
import org.jetbrains.skia.PictureRecorder
import org.jetbrains.skia.Rect
import org.jetbrains.skiko.SkiaLayer
import org.jetbrains.skiko.SkikoView
import java.awt.Container
import java.io.Closeable
import java.io.File
import javax.swing.JComponent

private fun <T : JComponent> findComponent(
    container: Container,
    klass: Class<T>,
): T? {
    val componentSequence = container.components.asSequence()
    return componentSequence.filter { klass.isInstance(it) }.ifEmpty {
        componentSequence.filterIsInstance<Container>()
            .mapNotNull { findComponent(it, klass) }
    }.map { klass.cast(it) }.firstOrNull()
}

private inline fun <reified T : JComponent> Container.findComponent() = findComponent(this, T::class.java)

fun ComposeWindow.findSkiaLayer(): SkiaLayer? = findComponent<SkiaLayer>()

class RecordingSkikoView(private val original: SkikoView) : SkikoView, Closeable {
    private val recorder = PictureRecorder()

    init {
        recorder.beginRecording(Rect(0f, 0f, 1024f, 768f))
    }

    override fun onRender(canvas: Canvas, width: Int, height: Int, nanoTime: Long) {
        original.onRender(recorder.recordingCanvas!!, width, height, nanoTime)
        original.onRender(canvas, width, height, nanoTime)
        save()
    }

    private fun save() {
        val pic = recorder.finishRecordingAsPicture()
        val picBytes = pic.serializeToData().bytes

        // save bytes to file
        File("skia_debugger.skp").writeBytes(picBytes)
        recorder.beginRecording(Rect(0f, 0f, 1024f, 768f))
    }

    override fun close() {
        recorder.close()
    }
}

fun ComposeWindow.attachSkiaDebugger() {
    val skiaLayer = findSkiaLayer() ?: error("SkiaLayer not found")
    val originalSkikoView = skiaLayer.skikoView ?: error("SkikoView not present")

    skiaLayer.skikoView = RecordingSkikoView(originalSkikoView)
}