PulsingCirclesDocument.kt

@RunWith(RobolectricTestRunner::class)
@Config(sdk = [35])
class PulsingCirclesDocument {

    @Test
    fun generate() {
        val context = ApplicationProvider.getApplicationContext<Context>()
        val displayInfo = RemoteCreationDisplayInfo(
            width = 1080,
            height = 1080,
            densityDpi = 420,
        )
        val doc = runBlocking {
            captureSingleRemoteDocument(
                context = context,
                creationDisplayInfo = displayInfo,
            ) {
                RemoteCanvas(
                    modifier = RemoteModifier.fillMaxSize().background(Color(0xFF0A0A23)),
                ) {
                    val cx = remote.component.centerX
                    val cy = remote.component.centerY
                    val maxRad = remote.component.width.min(remote.component.height) * 0.45f
                    val t = remote.time.ContinuousSec()

                    val colors = listOf(
                        Color(0xFFFF006E),
                        Color(0xFFFF4D6D),
                        Color(0xFFFB5607),
                        Color(0xFFFF9E00),
                        Color(0xFFFFBE0B),
                        Color(0xFF3A86FF),
                        Color(0xFF8338EC),
                    )

                    // Draw rings from outermost to innermost
                    for (i in colors.indices.reversed()) {
                        val baseRadius = maxRad * ((i + 1).toFloat() / colors.size)
                        // Each ring pulses with a phase offset
                        val pulse = sin(t * 2f + i.toFloat() * 0.8f) * maxRad * 0.06f
                        val radius = baseRadius + pulse

                        drawCircle(
                            paint = RemotePaint {
                                color = colors[i].rc
                                style = PaintingStyle.Stroke
                                strokeWidth = 8f.rf
                            },
                            center = RemoteOffset(cx, cy),
                            radius = radius,
                        )
                    }

                    // Glowing center dot
                    val centerPulse = (sin(t * 3f) + 1f.rf) * 10f + 15f
                    drawCircle(
                        paint = RemotePaint { color = Color(0xFFFFFFFF).rc },
                        center = RemoteOffset(cx, cy),
                        radius = centerPulse,
                    )
                }
            }
        }
        File("../output/pulsing_circles.rc").apply { parentFile?.mkdirs() }.writeBytes(doc.bytes)
    }
}