Support configurable vertical centering via LineHeightStyle.Alignment

compose/mpp/demo/src/commonMain/kotlin/androidx/compose/mpp/demo/MainScreen.kt

@@ -27,13 +27,10 @@ val MainScreen = Screen.Selection(
     BugReproducers,
     Screen.Example("Example1") { Example1() },
     Screen.Example("ImageViewer") { ImageViewer() },
-    Screen.Example("TextDirection") { TextDirection() },
-    Screen.Example("FontFamilies") { FontFamilies() },
     Screen.Example("LottieAnimation") { LottieAnimation() },
     Screen.Fullscreen("ApplicationLayouts") { ApplicationLayouts(it) },
     Screen.Example("GraphicsLayerSettings") { GraphicsLayerSettings() },
     Screen.Example("Blending") { Blending() },
-    Screen.Example("FontRasterization") { FontRasterization() },
     Screen.Example("InteropOrder") { InteropOrder() },
     AndroidTextFieldSamples,
     Screen.Example("Android TextBrushDemo") { TextBrushDemo() },

compose/mpp/demo/src/commonMain/kotlin/androidx/compose/mpp/demo/components/Components.kt

@@ -30,6 +30,7 @@ import androidx.compose.mpp.demo.components.material3.ModalNavigationDrawerExamp
 import androidx.compose.mpp.demo.components.material3.SearchBarExample
 import androidx.compose.mpp.demo.components.material3.WindowSizeClassExample
 import androidx.compose.mpp.demo.components.popup.Popups
+import androidx.compose.mpp.demo.components.text.TextDemos
 import androidx.compose.mpp.demo.textfield.TextFields
 import androidx.compose.runtime.Composable
 
@@ -56,6 +57,7 @@ val Components = Screen.Selection(
     "Components",
     Popups,
     Dialogs,
+    TextDemos,
     TextFields,
     LazyLayouts,
     MaterialComponents,

compose/mpp/demo/src/commonMain/kotlin/androidx/compose/mpp/demo/FontFamilies.kt → compose/mpp/demo/src/commonMain/kotlin/androidx/compose/mpp/demo/components/text/FontFamilies.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2023 The Android Open Source Project
+ * Copyright 2024 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package androidx.compose.mpp.demo
+package androidx.compose.mpp.demo.components.text
 
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
@@ -29,27 +29,23 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.unit.dp
 
-
 @Composable
 fun FontFamilies() {
-    val state = rememberScrollState()
-    MaterialTheme {
-        Column(
-            modifier = Modifier
-                .fillMaxSize()
-                .padding(10.dp)
-                .verticalScroll(state),
-            verticalArrangement = Arrangement
-                .spacedBy(10.dp)
-        ) {
-            for (fontFamily in listOf(
-                FontFamily.SansSerif,
-                FontFamily.Serif,
-                FontFamily.Monospace,
-                FontFamily.Cursive
-            )) {
-                FontFamilyShowcase(fontFamily)
-            }
+    Column(
+        modifier = Modifier
+            .fillMaxSize()
+            .padding(10.dp)
+            .verticalScroll(rememberScrollState()),
+        verticalArrangement = Arrangement
+            .spacedBy(10.dp)
+    ) {
+        for (fontFamily in listOf(
+            FontFamily.SansSerif,
+            FontFamily.Serif,
+            FontFamily.Monospace,
+            FontFamily.Cursive
+        )) {
+            FontFamilyShowcase(fontFamily)
         }
     }
 }
@@ -60,15 +56,16 @@ private fun FontFamilyShowcase(fontFamily: FontFamily) {
         Text(
             text = "$fontFamily"
         )
-        Text(
-            text = "The quick brown fox jumps over the lazy dog.",
+        val textStyle =  MaterialTheme.typography.h3.copy(
             fontFamily = fontFamily,
-            style = MaterialTheme.typography.h3
         )
-        Text(
+        TextWithMetrics(
+            text = "The quick brown fox jumps over the lazy dog.",
+            style = textStyle
+        )
+        TextWithMetrics(
             text = "1234567890",
-            fontFamily = fontFamily,
-            style = MaterialTheme.typography.h3
+            style = textStyle
         )
     }
 }

compose/mpp/demo/src/commonMain/kotlin/androidx/compose/mpp/demo/components/text/FontRasterization.kt

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package androidx.compose.mpp.demo.components.text
+
+import androidx.compose.foundation.border
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.offset
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.text.BasicText
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.text.ExperimentalTextApi
+import androidx.compose.ui.text.FontHinting
+import androidx.compose.ui.text.FontRasterizationSettings
+import androidx.compose.ui.text.FontSmoothing
+import androidx.compose.ui.text.PlatformParagraphStyle
+import androidx.compose.ui.text.PlatformTextStyle
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.unit.dp
+
+@OptIn(ExperimentalTextApi::class)
+@Composable
+fun FontRasterization() {
+    val state = rememberScrollState()
+    Column(
+        modifier = Modifier.fillMaxSize().padding(10.dp).verticalScroll(state),
+        verticalArrangement = Arrangement.spacedBy(10.dp)
+    ) {
+        val hintingOptions = listOf(FontHinting.None, FontHinting.Slight, FontHinting.Normal, FontHinting.Full)
+        val isAutoHintingForcedOptions = listOf(false, true)
+        val subpixelOptions = listOf(false, true)
+        val smoothingOptions = listOf(FontSmoothing.None, FontSmoothing.AntiAlias, FontSmoothing.SubpixelAntiAlias)
+        val text = "Lorem ipsum"
+
+        for (hinting in hintingOptions) {
+            Row(
+                horizontalArrangement = Arrangement.spacedBy(10.dp)
+            ) {
+                for (smoothing in smoothingOptions) {
+                    Column(
+                        modifier = Modifier.weight(1f).border(1.dp, Color.Black).padding(10.dp),
+                        verticalArrangement = Arrangement.spacedBy(10.dp)
+                    ) {
+                        for (subpixel in subpixelOptions) {
+                            for (autoHintingForced in isAutoHintingForcedOptions) {
+                                FontRasterizationSample(
+                                    text = text,
+                                    modifier = Modifier.offset(x = 0.25.dp, y = 0.25.dp),
+                                    hinting = hinting,
+                                    smoothing = smoothing,
+                                    subpixelPositioning = subpixel,
+                                    autoHintingForced = autoHintingForced
+                                )
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+@OptIn(ExperimentalTextApi::class)
+@Composable
+private fun FontRasterizationSample(
+    text: String,
+    modifier: Modifier,
+    hinting: FontHinting,
+    smoothing: FontSmoothing,
+    subpixelPositioning: Boolean,
+    autoHintingForced: Boolean
+) {
+    BasicText(
+        text = text,
+        modifier = modifier,
+        style = TextStyle(
+            platformStyle = PlatformTextStyle(
+                spanStyle = null,
+                paragraphStyle = PlatformParagraphStyle(
+                    fontRasterizationSettings = FontRasterizationSettings(
+                        smoothing = smoothing,
+                        hinting = hinting,
+                        subpixelPositioning = subpixelPositioning,
+                        autoHintingForced = autoHintingForced
+                    )
+                )
+            )
+        )
+    )
+}