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diff --git a/libs/hwui/renderstate/Stencil.h b/libs/hwui/renderstate/Stencil.h
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+++ b/libs/hwui/renderstate/Stencil.h
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+/*
+ * Copyright (C) 2012 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.
+ */
+
+#ifndef ANDROID_HWUI_STENCIL_H
+#define ANDROID_HWUI_STENCIL_H
+
+#ifndef LOG_TAG
+    #define LOG_TAG "OpenGLRenderer"
+#endif
+
+#include <GLES2/gl2.h>
+
+#include <cutils/compiler.h>
+
+namespace android {
+namespace uirenderer {
+
+///////////////////////////////////////////////////////////////////////////////
+// Stencil buffer management
+///////////////////////////////////////////////////////////////////////////////
+
+class ANDROID_API Stencil {
+public:
+    Stencil();
+
+    /**
+     * Returns the desired size for the stencil buffer. If the returned value
+     * is 0, then no stencil buffer is required.
+     */
+    ANDROID_API static uint8_t getStencilSize();
+
+    /**
+     * Returns the smallest stencil format accepted by render buffers.
+     */
+    static GLenum getSmallestStencilFormat();
+
+    /**
+     * Clears the stencil buffer.
+     */
+    void clear();
+
+    /**
+     * Enables stencil test. When the stencil test is enabled the stencil buffer is not written
+     * into. An increment threshold of zero causes the stencil to use a constant reference value
+     * and GL_EQUAL for the test. A non-zero increment threshold causes the stencil to use that
+     * value as the reference value and GL_EQUAL for the test.
+     */
+    void enableTest(int incrementThreshold);
+
+    /**
+     * Enables stencil write. When stencil write is enabled, the stencil
+     * test always succeeds and the value 0x1 is written in the stencil
+     * buffer for each fragment. An increment threshold of zero causes the stencil to use a constant
+     * reference value and GL_EQUAL for the test. A non-zero increment threshold causes the stencil
+     * to use that value as the reference value and GL_EQUAL for the test.
+     */
+    void enableWrite(int incrementThreshold);
+
+    /**
+     * The test passes only when equal to the specified value.
+     */
+    void enableDebugTest(GLint value, bool greater = false);
+
+    /**
+     * Used for debugging. The stencil test always passes and increments.
+     */
+    void enableDebugWrite();
+
+    /**
+     * Disables stencil test and write.
+     */
+    void disable();
+
+    /**
+     * Indicates whether either test or write is enabled.
+     */
+    bool isEnabled() {
+        return mState != kDisabled;
+    }
+
+    /**
+     * Indicates whether testing only is enabled.
+     */
+    bool isTestEnabled() {
+        return mState == kTest;
+    }
+
+    bool isWriteEnabled() {
+        return mState == kWrite;
+    }
+
+    void dump();
+
+private:
+    void enable();
+
+    enum StencilState {
+        kDisabled,
+        kTest,
+        kWrite
+    };
+
+    StencilState mState;
+
+}; // class Stencil
+
+}; // namespace uirenderer
+}; // namespace android
+
+#endif // ANDROID_HWUI_STENCIL_H