2 files changed, 165 insertions, 0 deletions
diff --git a/graphics/java/android/graphics/RenderEffect.java b/graphics/java/android/graphics/RenderEffect.java
new file mode 100644
index 000000000000..9fc0c8eb9d90
--- /dev/null
+++ b/graphics/java/android/graphics/RenderEffect.java
@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2020 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 android.graphics;
+
+import android.annotation.NonNull;
+import android.graphics.Shader.TileMode;
+
+import libcore.util.NativeAllocationRegistry;
+
+/**
+ * Intermediate rendering step used to render drawing commands with a corresponding
+ * visual effect
+ *
+ * @hide
+ */
+public final class RenderEffect {
+
+    private static class RenderEffectHolder {
+        public static final NativeAllocationRegistry RENDER_EFFECT_REGISTRY =
+                NativeAllocationRegistry.createMalloced(
+                        RenderEffect.class.getClassLoader(), nativeGetFinalizer());
+    }
+
+    /**
+     * Create a {@link RenderEffect} instance that will offset the drawing content
+     * by the provided x and y offset.
+     * @param offsetX offset along the x axis in pixels
+     * @param offsetY offset along the y axis in pixels
+     */
+    @NonNull
+    public static RenderEffect createOffsetEffect(float offsetX, float offsetY) {
+        return new RenderEffect(nativeCreateOffsetEffect(offsetX, offsetY, 0));
+    }
+
+    /**
+     * Create a {@link RenderEffect} instance with the provided x and y offset
+     * @param offsetX offset along the x axis in pixels
+     * @param offsetY offset along the y axis in pixels
+     * @param input target RenderEffect used to render in the offset coordinates.
+     */
+    @NonNull
+    public static RenderEffect createOffsetEffect(
+            float offsetX,
+            float offsetY,
+            @NonNull RenderEffect input
+    ) {
+        return new RenderEffect(nativeCreateOffsetEffect(
+                    offsetX,
+                    offsetY,
+                    input.getNativeInstance()
+                )
+        );
+    }
+
+    /**
+     * Create a {@link RenderEffect} that blurs the contents of the optional input RenderEffect
+     * with the specified radius along the x and y axis. If no input RenderEffect is provided
+     * then all drawing commands issued with a {@link android.graphics.RenderNode} that this
+     * RenderEffect is installed in will be blurred
+     * @param radiusX Radius of blur along the X axis
+     * @param radiusY Radius of blur along the Y axis
+     * @param inputEffect Input RenderEffect that provides the content to be blurred, can be null
+     *                    to indicate that the drawing commands on the RenderNode are to be
+     *                    blurred instead of the input RenderEffect
+     * @param edgeTreatment Policy for how to blur content near edges of the blur kernel
+     */
+    @NonNull
+    public static RenderEffect createBlurEffect(
+            float radiusX,
+            float radiusY,
+            @NonNull RenderEffect inputEffect,
+            @NonNull TileMode edgeTreatment
+    ) {
+        long nativeInputEffect = inputEffect != null ? inputEffect.mNativeRenderEffect : 0;
+        return new RenderEffect(
+                nativeCreateBlurEffect(
+                        radiusX,
+                        radiusY,
+                        nativeInputEffect,
+                        edgeTreatment.nativeInt
+                )
+            );
+    }
+
+    /**
+     * Create a {@link RenderEffect} that blurs the contents of the
+     * {@link android.graphics.RenderNode} that this RenderEffect is installed on with the
+     * specified radius along hte x and y axis.
+     * @param radiusX Radius of blur along the X axis
+     * @param radiusY Radius of blur along the Y axis
+     * @param edgeTreatment Policy for how to blur content near edges of the blur kernel
+     */
+    @NonNull
+    public static RenderEffect createBlurEffect(
+            float radiusX,
+            float radiusY,
+            @NonNull TileMode edgeTreatment
+    ) {
+        return new RenderEffect(
+                nativeCreateBlurEffect(
+                        radiusX,
+                        radiusY,
+                        0,
+                        edgeTreatment.nativeInt
+                )
+        );
+    }
+
+    private final long mNativeRenderEffect;
+
+    /* only constructed from static factory methods */
+    private RenderEffect(long nativeRenderEffect) {
+        mNativeRenderEffect = nativeRenderEffect;
+        RenderEffectHolder.RENDER_EFFECT_REGISTRY.registerNativeAllocation(
+                this, mNativeRenderEffect);
+    }
+
+    /**
+     * Obtain the pointer to the underlying RenderEffect to be configured
+     * on a RenderNode object via {@link RenderNode#setRenderEffect(RenderEffect)}
+     */
+    /* package */ long getNativeInstance() {
+        return mNativeRenderEffect;
+    }
+
+    private static native long nativeCreateOffsetEffect(
+            float offsetX, float offsetY, long nativeInput);
+    private static native long nativeCreateBlurEffect(
+            float radiusX, float radiusY, long nativeInput, int edgeTreatment);
+    private static native long nativeGetFinalizer();
+}
diff --git a/graphics/java/android/graphics/RenderNode.java b/graphics/java/android/graphics/RenderNode.java
index 8aacbc7bc109..d812c1a5595d 100644
--- a/graphics/java/android/graphics/RenderNode.java
+++ b/graphics/java/android/graphics/RenderNode.java
@@ -850,6 +850,23 @@ public final class RenderNode {
     }
 
     /**
+     * Configure the {@link android.graphics.RenderEffect} to apply to this RenderNode. This
+     * will apply a visual effect to the end result of the contents of this RenderNode before
+     * it is drawn into the destination. For example if
+     * {@link RenderEffect#createBlurEffect(float, float, RenderEffect, Shader.TileMode)}
+     * is provided, the contents will be drawn in a separate layer, then this layer will
+     * be blurred when this RenderNode is drawn into the destination.
+     * @param renderEffect to be applied to the RenderNode. Passing null clears all previously
+     *          configured RenderEffects
+     *
+     * @hide
+     */
+    public void setRenderEffect(@Nullable RenderEffect renderEffect) {
+        nSetRenderEffect(mNativeRenderNode,
+                renderEffect != null ? renderEffect.getNativeInstance() : 0);
+    }
+
+    /**
      * Returns the translucency level of this display list.
      *
      * @return A value between 0.0f and 1.0f
@@ -1655,6 +1672,9 @@ public final class RenderNode {
     private static native boolean nSetAlpha(long renderNode, float alpha);
 
     @CriticalNative
+    private static native void nSetRenderEffect(long renderNode, long renderEffect);
+
+    @CriticalNative
     private static native boolean nSetHasOverlappingRendering(long renderNode,
             boolean hasOverlappingRendering);