Refactoring of choosing orientation. Move logic into init method of L…

…ayerConfig.

future_changes.md

@@ -17,6 +17,11 @@
 
  See: [example notebook](https://nbviewer.org/github/JetBrains/lets-plot/blob/master/docs/f-24b/param_size_unit.ipynb).
 
+- Automatically choose `orientation="y"` when aes y is discrete [[#558](https://github.com/JetBrains/lets-plot/issues/558)].
+
+ See: [example notebook](https://nbviewer.org/github/JetBrains/lets-plot/blob/master/docs/f-24b/auto_rotate.ipynb).
+
+
 ### Changed
 
 ### Fixed

plot-stem/src/commonMain/kotlin/org/jetbrains/letsPlot/core/spec/config/DataConfigUtil.kt

@@ -135,6 +135,28 @@ internal object DataConfigUtil {
  )
  }
 
+ fun isAesDiscrete(
+ aes: Aes<*>,
+ sharedData: DataFrame,
+ layerData: DataFrame,
+ sharedMappings: Map<String, String>,
+ layerMappings: Map<String, String>,
+ combinedDiscreteMappings: Map<String, String>
+ ): Boolean {
+ // Checking if the y-axis mark as_discrete
+ if (combinedDiscreteMappings.containsKey(aes.name)) return true
+
+ // Checking if the y-axis is discrete
+ val aesName = layerMappings[aes.name] ?: sharedMappings[aes.name] ?: return false
+ // The logic of choosing the data frame is the same as in the layerMappingsAndCombinedData function
+ if (DataFrameUtil.hasVariable(layerData, aesName)
+ && DataFrameUtil.findVariableOrFail(layerData, aesName).let(layerData::isDiscrete)
+ ) return true
+
+ return (DataFrameUtil.hasVariable(sharedData, aesName)
+ && DataFrameUtil.findVariableOrFail(sharedData, aesName).let(sharedData::isDiscrete))
+ }
+
  fun combinedDataWithDataMeta(
  rawCombinedData: DataFrame,
  varBindings: List<VarBinding>,

plot-stem/src/commonMain/kotlin/org/jetbrains/letsPlot/core/spec/config/LayerConfig.kt

@@ -157,6 +157,26 @@ class LayerConfig(
  ownDiscreteAes = DataMetaUtil.getAsDiscreteAesSet(getMap(DATA_META))
  )
 
+ if (!clientSide
+ && isOrientationApplicable()
+ && !DataConfigUtil.isAesDiscrete(
+ Aes.X,
+ plotData,
+ ownData,
+ plotMappings,
+ layerMappings,
+ combinedDiscreteMappings
+ )
+ && DataConfigUtil.isAesDiscrete(
+ Aes.Y,
+ plotData,
+ ownData,
+ plotMappings,
+ layerMappings,
+ combinedDiscreteMappings
+ )
+ ) setOrientationY()
+
  val consumedAesSet: Set<Aes<*>> = renderedAes.toSet().let {
  when (clientSide) {
  true -> it
@@ -279,6 +299,31 @@ class LayerConfig(
  combinedDataValid = false
  }
 
+ private fun isOrientationApplicable(): Boolean {
+ val isSuitableGeomKind = geomProto.geomKind in listOf(
+ GeomKind.BAR,
+ GeomKind.BOX_PLOT,
+ GeomKind.VIOLIN,
+ GeomKind.LOLLIPOP,
+ GeomKind.Y_DOT_PLOT
+ )
+ val isSuitableStatKind = statKind in listOf(
+ StatKind.COUNT,
+ StatKind.SUMMARY,
+ StatKind.BOXPLOT,
+ StatKind.BOXPLOT_OUTLIER,
+ StatKind.YDOTPLOT,
+ StatKind.YDENSITY
+ )
+
+ return isSuitableGeomKind || isSuitableStatKind
+ }
+
+ private fun setOrientationY() {
+ check(!clientSide)
+ update(ORIENTATION, "y")
+ }
+
  fun hasExplicitGrouping(): Boolean {
  return explicitGroupingVarName != null
  }