Better handling for undefined icon|text-rotation-alignment (#6253)

* [core, ios, android] Use `auto` value for properties with calculated defaults

* Fix render tests

4 files changed, 24 insertions, 14 deletions

diff --git a/src/mbgl/style/layers/symbol_layer.cpp b/src/mbgl/style/layers/symbol_layer.cpp
index c9fd2c0988..6b4d7400da 100644
--- a/src/mbgl/style/layers/symbol_layer.cpp
+++ b/src/mbgl/style/layers/symbol_layer.cpp
@@ -144,7 +144,7 @@ void SymbolLayer::setIconOptional(PropertyValue<bool> value) {
     impl->observer->onLayerLayoutPropertyChanged(*this);
 }
 PropertyValue<AlignmentType> SymbolLayer::getDefaultIconRotationAlignment() {
-    return { AlignmentType::Viewport };
+    return { AlignmentType::Auto };
 }
 
 PropertyValue<AlignmentType> SymbolLayer::getIconRotationAlignment() const {
@@ -270,7 +270,7 @@ void SymbolLayer::setIconOffset(PropertyValue<std::array<float, 2>> value) {
     impl->observer->onLayerLayoutPropertyChanged(*this);
 }
 PropertyValue<AlignmentType> SymbolLayer::getDefaultTextPitchAlignment() {
-    return { AlignmentType::Undefined };
+    return { AlignmentType::Auto };
 }
 
 PropertyValue<AlignmentType> SymbolLayer::getTextPitchAlignment() const {
@@ -284,7 +284,7 @@ void SymbolLayer::setTextPitchAlignment(PropertyValue<AlignmentType> value) {
     impl->observer->onLayerLayoutPropertyChanged(*this);
 }
 PropertyValue<AlignmentType> SymbolLayer::getDefaultTextRotationAlignment() {
-    return { AlignmentType::Viewport };
+    return { AlignmentType::Auto };
 }
 
 PropertyValue<AlignmentType> SymbolLayer::getTextRotationAlignment() const {
diff --git a/src/mbgl/style/layers/symbol_layer_impl.cpp b/src/mbgl/style/layers/symbol_layer_impl.cpp
index 1039951f5e..e85f3a90f9 100644
--- a/src/mbgl/style/layers/symbol_layer_impl.cpp
+++ b/src/mbgl/style/layers/symbol_layer_impl.cpp
@@ -35,19 +35,29 @@ std::unique_ptr<SymbolLayout> SymbolLayer::Impl::createLayout(BucketParameters&
     SymbolLayoutProperties layoutProperties = layout;
 
     CalculationParameters p(parameters.tileID.overscaledZ);
-    layoutProperties.symbolPlacement.calculate(p);
-    if (layoutProperties.symbolPlacement.value == SymbolPlacementType::Line) {
-        layoutProperties.iconRotationAlignment.value = AlignmentType::Map;
-        layoutProperties.textRotationAlignment.value = AlignmentType::Map;
+    layoutProperties.recalculate(p);
+
+    if (layoutProperties.iconRotationAlignment.value == AlignmentType::Auto) {
+        if (layoutProperties.symbolPlacement.value == SymbolPlacementType::Line) {
+            layoutProperties.iconRotationAlignment.value = AlignmentType::Map;
+        } else {
+            layoutProperties.iconRotationAlignment.value = AlignmentType::Viewport;
+        }
+    }
+
+    if (layoutProperties.textRotationAlignment.value == AlignmentType::Auto) {
+        if (layoutProperties.symbolPlacement.value == SymbolPlacementType::Line) {
+            layoutProperties.textRotationAlignment.value = AlignmentType::Map;
+        } else {
+            layoutProperties.textRotationAlignment.value = AlignmentType::Viewport;
+        }
     }
 
     // If unspecified `text-pitch-alignment` inherits `text-rotation-alignment`
-    if (layoutProperties.textPitchAlignment.value == AlignmentType::Undefined) {
+    if (layoutProperties.textPitchAlignment.value == AlignmentType::Auto) {
         layoutProperties.textPitchAlignment.value = layoutProperties.textRotationAlignment.value;
     }
 
-    layoutProperties.recalculate(p);
-
     layoutProperties.textSize.calculate(CalculationParameters(18));
     float textMaxSize = layoutProperties.textSize;
 
diff --git a/src/mbgl/style/layers/symbol_layer_properties.hpp b/src/mbgl/style/layers/symbol_layer_properties.hpp
index e4560ab486..fefa0ae05e 100644
--- a/src/mbgl/style/layers/symbol_layer_properties.hpp
+++ b/src/mbgl/style/layers/symbol_layer_properties.hpp
@@ -22,7 +22,7 @@ public:
     LayoutProperty<bool> iconAllowOverlap { false };
     LayoutProperty<bool> iconIgnorePlacement { false };
     LayoutProperty<bool> iconOptional { false };
-    LayoutProperty<AlignmentType> iconRotationAlignment { AlignmentType::Viewport };
+    LayoutProperty<AlignmentType> iconRotationAlignment { AlignmentType::Auto };
     LayoutProperty<float> iconSize { 1 };
     LayoutProperty<IconTextFitType> iconTextFit { IconTextFitType::None };
     LayoutProperty<std::array<float, 4>> iconTextFitPadding { {{ 0, 0, 0, 0 }} };
@@ -31,8 +31,8 @@ public:
     LayoutProperty<float> iconPadding { 2 };
     LayoutProperty<bool> iconKeepUpright { false };
     LayoutProperty<std::array<float, 2>> iconOffset { {{ 0, 0 }} };
-    LayoutProperty<AlignmentType> textPitchAlignment { AlignmentType::Undefined };
-    LayoutProperty<AlignmentType> textRotationAlignment { AlignmentType::Viewport };
+    LayoutProperty<AlignmentType> textPitchAlignment { AlignmentType::Auto };
+    LayoutProperty<AlignmentType> textRotationAlignment { AlignmentType::Auto };
     LayoutProperty<std::string> textField { "" };
     LayoutProperty<std::vector<std::string>> textFont { { "Open Sans Regular", "Arial Unicode MS Regular" } };
     LayoutProperty<float> textSize { 16 };
diff --git a/src/mbgl/style/types.cpp b/src/mbgl/style/types.cpp
index be0b217134..bf2ba8a793 100644
--- a/src/mbgl/style/types.cpp
+++ b/src/mbgl/style/types.cpp
@@ -79,7 +79,7 @@ MBGL_DEFINE_ENUM(TextTransformType, {
 MBGL_DEFINE_ENUM(AlignmentType, {
     { AlignmentType::Map, "map" },
     { AlignmentType::Viewport, "viewport" },
-    { AlignmentType::Undefined, "undefined" },
+    { AlignmentType::Auto, "auto" },
 });
 
 MBGL_DEFINE_ENUM(IconTextFitType, {