1 files changed, 123 insertions, 0 deletions
diff --git a/libs/hwui/Interpolator.cpp b/libs/hwui/Interpolator.cpp
new file mode 100644
index 0000000..1f84b86
--- /dev/null
+++ b/libs/hwui/Interpolator.cpp
@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2014 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.
+ */
+
+#define LOG_TAG "Interpolator"
+
+#include "Interpolator.h"
+
+#include <cmath>
+#include <cutils/log.h>
+
+#include "utils/MathUtils.h"
+
+namespace android {
+namespace uirenderer {
+
+Interpolator* Interpolator::createDefaultInterpolator() {
+    return new AccelerateDecelerateInterpolator();
+}
+
+float AccelerateDecelerateInterpolator::interpolate(float input) {
+    return (float)(cosf((input + 1) * M_PI) / 2.0f) + 0.5f;
+}
+
+float AccelerateInterpolator::interpolate(float input) {
+    if (mFactor == 1.0f) {
+        return input * input;
+    } else {
+        return pow(input, mDoubleFactor);
+    }
+}
+
+float AnticipateInterpolator::interpolate(float t) {
+    return t * t * ((mTension + 1) * t - mTension);
+}
+
+static float a(float t, float s) {
+    return t * t * ((s + 1) * t - s);
+}
+
+static float o(float t, float s) {
+    return t * t * ((s + 1) * t + s);
+}
+
+float AnticipateOvershootInterpolator::interpolate(float t) {
+    if (t < 0.5f) return 0.5f * a(t * 2.0f, mTension);
+    else return 0.5f * (o(t * 2.0f - 2.0f, mTension) + 2.0f);
+}
+
+static float bounce(float t) {
+    return t * t * 8.0f;
+}
+
+float BounceInterpolator::interpolate(float t) {
+    t *= 1.1226f;
+    if (t < 0.3535f) return bounce(t);
+    else if (t < 0.7408f) return bounce(t - 0.54719f) + 0.7f;
+    else if (t < 0.9644f) return bounce(t - 0.8526f) + 0.9f;
+    else return bounce(t - 1.0435f) + 0.95f;
+}
+
+float CycleInterpolator::interpolate(float input) {
+    return sinf(2 * mCycles * M_PI * input);
+}
+
+float DecelerateInterpolator::interpolate(float input) {
+    float result;
+    if (mFactor == 1.0f) {
+        result = 1.0f - (1.0f - input) * (1.0f - input);
+    } else {
+        result = 1.0f - pow((1.0f - input), 2 * mFactor);
+    }
+    return result;
+}
+
+float OvershootInterpolator::interpolate(float t) {
+    t -= 1.0f;
+    return t * t * ((mTension + 1) * t + mTension) + 1.0f;
+}
+
+LUTInterpolator::LUTInterpolator(float* values, size_t size) {
+    mValues = values;
+    mSize = size;
+}
+
+LUTInterpolator::~LUTInterpolator() {
+    delete mValues;
+    mValues = 0;
+}
+
+float LUTInterpolator::interpolate(float input) {
+    float lutpos = input * mSize;
+    if (lutpos >= (mSize - 1)) {
+        return mValues[mSize - 1];
+    }
+
+    float ipart, weight;
+    weight = modff(lutpos, &ipart);
+
+    int i1 = (int) ipart;
+    int i2 = MathUtils::min(i1 + 1, mSize - 1);
+
+    float v1 = mValues[i1];
+    float v2 = mValues[i2];
+
+    return MathUtils::lerp(v1, v2, weight);
+}
+
+
+} /* namespace uirenderer */
+} /* namespace android */