Add PlotPanelRaw for rendering raw specs.

Author: alshan

lets-plot-compose/src/androidMain/kotlin/org/jetbrains/letsPlot/skia/compose/PlotPanel.kt renamed to lets-plot-compose/src/androidMain/kotlin/org/jetbrains/letsPlot/skia/compose/PlotPanelRaw.kt

@@ -8,10 +8,8 @@ package org.jetbrains.letsPlot.skia.compose
 import androidx.compose.runtime.*
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.viewinterop.AndroidView
-import org.jetbrains.letsPlot.Figure
 import org.jetbrains.letsPlot.android.canvas.CanvasView
 import org.jetbrains.letsPlot.core.util.sizing.SizingPolicy
-import org.jetbrains.letsPlot.intern.toSpec
 import org.jetbrains.letsPlot.raster.builder.MonolithicCanvas
 import org.jetbrains.letsPlot.raster.view.PlotCanvasFigure
 import org.jetbrains.letsPlot.skia.compose.util.NaiveLogger
@@ -20,8 +18,8 @@ private val LOG = NaiveLogger("PlotPanel")
 
 @Suppress("FunctionName")
 @Composable
-actual fun PlotPanel(
-    figure: Figure,
+actual fun PlotPanelRaw(
+    rawSpec: MutableMap<String, Any>,
     preserveAspectRatio: Boolean,
     modifier: Modifier,
     computationMessagesHandler: (List<String>) -> Unit
@@ -41,7 +39,7 @@ actual fun PlotPanel(
         update = { canvasView ->
             MonolithicCanvas.updatePlotFigureFromRawSpec(
                 plotCanvasFigure = plotCanvasFigure,
-                rawSpec = figure.toSpec(),
+                rawSpec = rawSpec,
                 sizingPolicy = SizingPolicy.fitContainerSize(preserveAspectRatio),
                 computationMessagesHandler = computationMessagesHandler
             )

lets-plot-compose/src/commonMain/kotlin/org/jetbrains/letsPlot/skia/compose/PlotPanel.kt

@@ -6,15 +6,26 @@
 package org.jetbrains.letsPlot.skia.compose
 
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
 import org.jetbrains.letsPlot.Figure
-
+import org.jetbrains.letsPlot.intern.toSpec
 
 @Suppress("FunctionName")
 @Composable
-expect fun PlotPanel(
+fun PlotPanel(
     figure: Figure,
     preserveAspectRatio: Boolean = false,
     modifier: Modifier,
     computationMessagesHandler: (List<String>) -> Unit
-)
+) {
+    // Cache the raw spec conversion to avoid recomputing on every recomposition
+    val rawSpec = remember(figure) { figure.toSpec() }
+
+    PlotPanelRaw(
+        rawSpec = rawSpec,
+        preserveAspectRatio = preserveAspectRatio,
+        modifier = modifier,
+        computationMessagesHandler = computationMessagesHandler
+    )
+}

lets-plot-compose/src/commonMain/kotlin/org/jetbrains/letsPlot/skia/compose/PlotPanelRaw.kt

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2025 JetBrains s.r.o.
+ * Use of this source code is governed by the MIT license that can be found in the LICENSE file.
+ */
+
+package org.jetbrains.letsPlot.skia.compose
+
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+
+// Core expect function - works with raw specs
+@Suppress("FunctionName")
+@Composable
+expect fun PlotPanelRaw(
+    rawSpec: MutableMap<String, Any>,
+    preserveAspectRatio: Boolean,
+    modifier: Modifier,
+    computationMessagesHandler: (List<String>) -> Unit
+)

lets-plot-compose/src/commonMain/kotlin/org/jetbrains/letsPlot/skia/compose/WithRawSpec.kt

@@ -15,14 +15,12 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.layout.onSizeChanged
 import androidx.compose.ui.platform.LocalDensity
-import org.jetbrains.letsPlot.Figure
 import org.jetbrains.letsPlot.commons.geometry.DoubleVector
 import org.jetbrains.letsPlot.core.plot.builder.interact.tools.FigureModelHelper
 import org.jetbrains.letsPlot.core.spec.Option.Meta.Kind.GG_TOOLBAR
 import org.jetbrains.letsPlot.core.spec.front.SpecOverrideUtil
 import org.jetbrains.letsPlot.core.util.MonolithicCommon.processRawSpecs
 import org.jetbrains.letsPlot.core.util.sizing.SizingPolicy
-import org.jetbrains.letsPlot.intern.toSpec
 import org.jetbrains.letsPlot.skia.builderLW.MonolithicSkiaLW
 import org.jetbrains.letsPlot.skia.compose.desktop.PlotContainer
 import org.jetbrains.letsPlot.skia.compose.desktop.SvgViewPanel
@@ -32,21 +30,17 @@ private val LOG = NaiveLogger("PlotPanel")
 
 @Suppress("FunctionName")
 @Composable
-actual fun PlotPanel(
-    figure: Figure,
+actual fun PlotPanelRaw(
+    rawSpec: MutableMap<String, Any>,
     preserveAspectRatio: Boolean,
     modifier: Modifier,
     computationMessagesHandler: (List<String>) -> Unit
 ) {
     // Update density on each recomposition to handle monitor DPI changes (e.g., drag between HIDPI/regular monitor)
     val density = LocalDensity.current.density.toDouble()
 
-    // Cache plot processed spec to avoid reprocessing the same figure on every recomposition.
-    val processedPlotSpec by remember(figure) {
-        val rawSpec = when (figure) {
-            is WithRawSpec -> figure.rawSpec
-            else -> figure.toSpec()
-        }
+    // Cache processed plot spec to avoid reprocessing the same raw spec on every recomposition.
+    val processedPlotSpec by remember(rawSpec) {
         mutableStateOf(processRawSpecs(rawSpec, frontendOnly = false))
     }
     var panelSize by remember { mutableStateOf(DoubleVector.ZERO) }