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diff --git a/libs/hwui/UvMapper.h b/libs/hwui/UvMapper.h
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+/*
+ * Copyright (C) 2013 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_UV_MAPPER_H
+#define ANDROID_HWUI_UV_MAPPER_H
+
+#include "Rect.h"
+
+namespace android {
+namespace uirenderer {
+
+/**
+ * This class can be used to map UV coordinates from the [0..1]
+ * range to other arbitrary ranges. All the methods below assume
+ * that the input values lie in the [0..1] range already.
+ */
+class UvMapper {
+public:
+    /**
+     * Using this constructor is equivalent to not using any mapping at all.
+     * UV coordinates in the [0..1] range remain in the [0..1] range.
+     */
+    UvMapper(): mIdentity(true), mMinU(0.0f), mMaxU(1.0f), mMinV(0.0f), mMaxV(1.0f) {
+    }
+
+    /**
+     * Creates a new mapper with the specified ranges for U and V coordinates.
+     * The parameter minU must be < maxU and minV must be < maxV.
+     */
+    UvMapper(float minU, float maxU, float minV, float maxV):
+        mMinU(minU), mMaxU(maxU), mMinV(minV), mMaxV(maxV) {
+        checkIdentity();
+    }
+
+    /**
+     * Returns true if calling the map*() methods has no effect (that is,
+     * texture coordinates remain in the 0..1 range.)
+     */
+    bool isIdentity() const {
+        return mIdentity;
+    }
+
+    /**
+     * Changes the U and V mapping ranges.
+     * The parameter minU must be < maxU and minV must be < maxV.
+     */
+    void setMapping(float minU, float maxU, float minV, float maxV) {
+        mMinU = minU;
+        mMaxU = maxU;
+        mMinV = minV;
+        mMaxV = maxV;
+        checkIdentity();
+    }
+
+    /**
+     * Maps a single value in the U range.
+     */
+    void mapU(float& u) const {
+        if (!mIdentity) u = lerp(mMinU, mMaxU, u);
+    }
+
+    /**
+     * Maps a single value in the V range.
+     */
+    void mapV(float& v) const {
+        if (!mIdentity) v = lerp(mMinV, mMaxV, v);
+    }
+
+    /**
+     * Maps the specified rectangle in place. This method assumes:
+     * - left = min. U
+     * - top = min. V
+     * - right = max. U
+     * - bottom = max. V
+     */
+    void map(Rect& texCoords) const {
+        if (!mIdentity) {
+            texCoords.left = lerp(mMinU, mMaxU, texCoords.left);
+            texCoords.right = lerp(mMinU, mMaxU, texCoords.right);
+            texCoords.top = lerp(mMinV, mMaxV, texCoords.top);
+            texCoords.bottom = lerp(mMinV, mMaxV, texCoords.bottom);
+        }
+    }
+
+    /**
+     * Maps the specified UV coordinates in place.
+     */
+    void map(float& u1, float& v1, float& u2, float& v2) const {
+        if (!mIdentity) {
+            u1 = lerp(mMinU, mMaxU, u1);
+            u2 = lerp(mMinU, mMaxU, u2);
+            v1 = lerp(mMinV, mMaxV, v1);
+            v2 = lerp(mMinV, mMaxV, v2);
+        }
+    }
+
+    void dump() const {
+        ALOGD("mapper[minU=%.2f maxU=%.2f minV=%.2f maxV=%.2f]", mMinU, mMaxU, mMinV, mMaxV);
+    }
+
+private:
+    static float lerp(float start, float stop, float amount) {
+        return start + (stop - start) * amount;
+    }
+
+    void checkIdentity() {
+        mIdentity = mMinU == 0.0f && mMaxU == 1.0f && mMinV == 0.0f && mMaxV == 1.0f;
+    }
+
+    bool mIdentity;
+    float mMinU;
+    float mMaxU;
+    float mMinV;
+    float mMaxV;
+};
+
+}; // namespace uirenderer
+}; // namespace android
+
+#endif // ANDROID_HWUI_UV_MAPPER_H