comment cleanup for min and max zoom ratio functions

Author: lucasoskorep

packages/camera/camera_android/android/build.gradle

@@ -59,7 +59,6 @@ android {
 }
 
 dependencies {
-    testImplementation project(path: ':camera_android')
     compileOnly 'androidx.annotation:annotation:1.1.0'
     testImplementation 'junit:junit:4.13.2'
     testImplementation 'org.mockito:mockito-inline:4.6.1'

packages/camera/camera_android/android/src/main/java/io/flutter/plugins/camera/CameraProperties.java

@@ -147,7 +147,7 @@ public interface CameraProperties {
    * height and crop region height, for @see android.scaler.cropRegion.
    *
    * <p>By default maps to the @see
-   * android.hardware.camera2.CameraCharacteristics#SCALER_AVAILABLE_MAX_DIGITAL_ZOOM key
+   * android.hardware.camera2.CameraCharacteristics#SCALER_AVAILABLE_MAX_DIGITAL_ZOOM key.
    *
    * @return Float Maximum ratio between both active area width and crop region width, and active
    *     area height and crop region height.

packages/camera/camera_android/android/src/main/java/io/flutter/plugins/camera/features/zoomlevel/ZoomLevelFeature.java

@@ -12,9 +12,10 @@
 
 /** Controls the zoom configuration on the {@link android.hardware.camera2} API. */
 public class ZoomLevelFeature extends CameraFeature<Float> {
+  private static final Float defaultZoomLevel = 1.0f;
   private final boolean hasSupport;
   private final Rect sensorArraySize;
-  private Float currentSetting = 1.0f;
+  private Float currentSetting = defaultZoomLevel;
   private Float minimumZoomLevel = currentSetting;
   private Float maximumZoomLevel;
 
@@ -33,12 +34,12 @@ public ZoomLevelFeature(CameraProperties cameraProperties) {
       hasSupport = false;
       return;
     }
-
-    if (Build.VERSION.SDK_INT > Build.VERSION_CODES.R) {
+    // On Android 11+ CONTROL_ZOOM_RATIO_RANGE should be use to get the zoom ratio directly
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
       minimumZoomLevel = cameraProperties.getScalerMinZoomRatio();
       maximumZoomLevel = cameraProperties.getScalerMaxZoomRatio();
     } else {
-      minimumZoomLevel = 1.0f;
+      minimumZoomLevel = defaultZoomLevel;
       Float maxDigitalZoom = cameraProperties.getScalerAvailableMaxDigitalZoom();
       maximumZoomLevel =
           ((maxDigitalZoom == null) || (maxDigitalZoom < minimumZoomLevel))
@@ -74,7 +75,8 @@ public void updateBuilder(CaptureRequest.Builder requestBuilder) {
     if (!checkIsSupported()) {
       return;
     }
-    if (Build.VERSION.SDK_INT > Build.VERSION_CODES.R) {
+    // On Android 11+ CONTROL_ZOOM_RATIO should be use to get the zoom ratio directly
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
       requestBuilder.set(
           CaptureRequest.CONTROL_ZOOM_RATIO,
           ZoomUtils.computeZoomRatio(currentSetting, minimumZoomLevel, maximumZoomLevel));

packages/camera/camera_android/android/src/main/java/io/flutter/plugins/camera/features/zoomlevel/ZoomUtils.java

@@ -18,7 +18,8 @@ final class ZoomUtils {
    * Computes an image sensor area based on the supplied zoom settings.
    *
    * <p>The returned image sensor area can be applied to the {@link android.hardware.camera2} API in
-   * order to control zoom levels.
+   * order to control zoom levels. This method of zoom should only be used for android versions less
+   * than than 11 as past that the newer computeZoomRatio functional can be used.
    *
    * @param zoom The desired zoom level.
    * @param sensorArraySize The current area of the image sensor.
@@ -28,7 +29,7 @@ final class ZoomUtils {
    */
   static Rect computeZoomRect(
       float zoom, @NonNull Rect sensorArraySize, float minimumZoomLevel, float maximumZoomLevel) {
-    final float newZoom = MathUtils.clamp(zoom, minimumZoomLevel, maximumZoomLevel);
+    final float newZoom = computeZoomRatio(zoom, minimumZoomLevel, maximumZoomLevel);
 
     final int centerX = sensorArraySize.width() / 2;
     final int centerY = sensorArraySize.height() / 2;

packages/camera/camera_android/android/src/test/java/io/flutter/plugins/camera/features/zoomlevel/ZoomLevelFeatureTest.java

@@ -18,7 +18,10 @@
 
 import android.graphics.Rect;
 import android.hardware.camera2.CaptureRequest;
+import android.os.Build;
 import io.flutter.plugins.camera.CameraProperties;
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -147,6 +150,22 @@ public void updateBuilder_shouldSetScalarCropRegionWhenCheckIsSupportIsTrue() {
     verify(mockBuilder, times(1)).set(CaptureRequest.SCALER_CROP_REGION, mockZoomArea);
   }
 
+  @Test
+  public void updateBuilder_shouldControlZoomRatioWhenCheckIsSupportIsTrue() throws Exception {
+    setSdkVersion(Build.VERSION_CODES.R);
+    when(mockCameraProperties.getSensorInfoActiveArraySize()).thenReturn(mockSensorArray);
+    when(mockCameraProperties.getScalerMaxZoomRatio()).thenReturn(42f);
+    when(mockCameraProperties.getScalerMinZoomRatio()).thenReturn(1.0f);
+
+    ZoomLevelFeature zoomLevelFeature = new ZoomLevelFeature(mockCameraProperties);
+
+    CaptureRequest.Builder mockBuilder = mock(CaptureRequest.Builder.class);
+
+    zoomLevelFeature.updateBuilder(mockBuilder);
+
+    verify(mockBuilder, times(1)).set(CaptureRequest.CONTROL_ZOOM_RATIO, 0.0f);
+  }
+
   @Test
   public void getMinimumZoomLevel() {
     ZoomLevelFeature zoomLevelFeature = new ZoomLevelFeature(mockCameraProperties);
@@ -163,4 +182,38 @@ public void getMaximumZoomLevel() {
 
     assertEquals(42f, zoomLevelFeature.getMaximumZoomLevel(), 0);
   }
+
+  @Test
+  public void checkZoomLevelFeature_callsMaxDigitalZoomOnAndroidQ() throws Exception {
+    setSdkVersion(Build.VERSION_CODES.Q);
+
+    when(mockCameraProperties.getSensorInfoActiveArraySize()).thenReturn(mockSensorArray);
+
+    new ZoomLevelFeature(mockCameraProperties);
+
+    verify(mockCameraProperties, times(0)).getScalerMaxZoomRatio();
+    verify(mockCameraProperties, times(0)).getScalerMinZoomRatio();
+    verify(mockCameraProperties, times(1)).getScalerAvailableMaxDigitalZoom();
+  }
+
+  @Test
+  public void checkZoomLevelFeature_callsScalarMaxZoomRatioOnAndroidR() throws Exception {
+    setSdkVersion(Build.VERSION_CODES.R);
+    when(mockCameraProperties.getSensorInfoActiveArraySize()).thenReturn(mockSensorArray);
+
+    new ZoomLevelFeature(mockCameraProperties);
+
+    verify(mockCameraProperties, times(1)).getScalerMaxZoomRatio();
+    verify(mockCameraProperties, times(1)).getScalerMinZoomRatio();
+    verify(mockCameraProperties, times(0)).getScalerAvailableMaxDigitalZoom();
+  }
+
+  static void setSdkVersion(int sdkVersion) throws Exception {
+    Field sdkInt = Build.VERSION.class.getField("SDK_INT");
+    sdkInt.setAccessible(true);
+    Field modifiersField = Field.class.getDeclaredField("modifiers");
+    modifiersField.setAccessible(true);
+    modifiersField.setInt(sdkInt, sdkInt.getModifiers() & ~Modifier.FINAL);
+    sdkInt.set(null, sdkVersion);
+  }
 }