VectorDrawable native rendering - Step 1 of MANY

Implement path parsing from string to skia path in native. The parsing
contains two main stages:
1) Parse string into a list of nodes that contains one operation (such
   as move) and a vector of floats as params for that operation.
2) Interpret the operations defined in the nodes into SkPath operations,
   and create a skia path

Also provided unit test for parsing a string path into a list of nodes,
and then to a skia path.

Change-Id: I0ce13df5e3bb90987dcdc80fe8b039af175ad2e2
diff --git a/libs/hwui/Android.mk b/libs/hwui/Android.mk
index 9d3d4ae..95e4e77 100644
--- a/libs/hwui/Android.mk
+++ b/libs/hwui/Android.mk
@@ -64,6 +64,7 @@
     PatchCache.cpp \
     PathCache.cpp \
     PathTessellator.cpp \
+    PathParser.cpp \
     PixelBuffer.cpp \
     Program.cpp \
     ProgramCache.cpp \
@@ -82,6 +83,7 @@
     TextDropShadowCache.cpp \
     Texture.cpp \
     TextureCache.cpp \
+    VectorDrawablePath.cpp \
     protos/hwui.proto
 
 hwui_cflags := \
@@ -213,6 +215,7 @@
     unit_tests/FatVectorTests.cpp \
     unit_tests/LayerUpdateQueueTests.cpp \
     unit_tests/LinearAllocatorTests.cpp \
+    unit_tests/PathParserTests.cpp \
     unit_tests/StringUtilsTests.cpp
 
 ifeq (true, $(HWUI_NEW_OPS))
diff --git a/libs/hwui/PathParser.cpp b/libs/hwui/PathParser.cpp
new file mode 100644
index 0000000..e8ed8a1
--- /dev/null
+++ b/libs/hwui/PathParser.cpp
@@ -0,0 +1,193 @@
+/*
+ * Copyright (C) 2015 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.
+ */
+
+#include "PathParser.h"
+
+#include "jni.h"
+
+#include <utils/Log.h>
+#include <sstream>
+#include <stdlib.h>
+#include <string>
+#include <vector>
+
+namespace android {
+namespace uirenderer {
+
+static size_t nextStart(const char* s, size_t length, size_t startIndex) {
+    size_t index = startIndex;
+    while (index < length) {
+        char c = s[index];
+        // Note that 'e' or 'E' are not valid path commands, but could be
+        // used for floating point numbers' scientific notation.
+        // Therefore, when searching for next command, we should ignore 'e'
+        // and 'E'.
+        if ((((c - 'A') * (c - 'Z') <= 0) || ((c - 'a') * (c - 'z') <= 0))
+                && c != 'e' && c != 'E') {
+            return index;
+        }
+        index++;
+    }
+    return index;
+}
+
+/**
+ * Calculate the position of the next comma or space or negative sign
+ * @param s the string to search
+ * @param start the position to start searching
+ * @param result the result of the extraction, including the position of the
+ * the starting position of next number, whether it is ending with a '-'.
+ */
+static void extract(int* outEndPosition, bool* outEndWithNegOrDot, const char* s, int start, int end) {
+    // Now looking for ' ', ',', '.' or '-' from the start.
+    int currentIndex = start;
+    bool foundSeparator = false;
+    *outEndWithNegOrDot = false;
+    bool secondDot = false;
+    bool isExponential = false;
+    for (; currentIndex < end; currentIndex++) {
+        bool isPrevExponential = isExponential;
+        isExponential = false;
+        char currentChar = s[currentIndex];
+        switch (currentChar) {
+        case ' ':
+        case ',':
+            foundSeparator = true;
+            break;
+        case '-':
+            // The negative sign following a 'e' or 'E' is not a separator.
+            if (currentIndex != start && !isPrevExponential) {
+                foundSeparator = true;
+                *outEndWithNegOrDot = true;
+            }
+            break;
+        case '.':
+            if (!secondDot) {
+                secondDot = true;
+            } else {
+                // This is the second dot, and it is considered as a separator.
+                foundSeparator = true;
+                *outEndWithNegOrDot = true;
+            }
+            break;
+        case 'e':
+        case 'E':
+            isExponential = true;
+            break;
+        }
+        if (foundSeparator) {
+            break;
+        }
+    }
+    // In the case where nothing is found, we put the end position to the end of
+    // our extract range. Otherwise, end position will be where separator is found.
+    *outEndPosition = currentIndex;
+}
+
+/**
+* Parse the floats in the string.
+* This is an optimized version of parseFloat(s.split(",|\\s"));
+*
+* @param s the string containing a command and list of floats
+* @return array of floats
+*/
+static void getFloats(std::vector<float>* outPoints, const char* pathStr, int start, int end) {
+
+    if (pathStr[start] == 'z' || pathStr[start] == 'Z') {
+        return;
+    }
+    int startPosition = start + 1;
+    int endPosition = start;
+
+    // The startPosition should always be the first character of the
+    // current number, and endPosition is the character after the current
+    // number.
+    while (startPosition < end) {
+        bool endWithNegOrDot;
+        extract(&endPosition, &endWithNegOrDot, pathStr, startPosition, end);
+
+        if (startPosition < endPosition) {
+            outPoints->push_back(strtof(&pathStr[startPosition], NULL));
+        }
+
+        if (endWithNegOrDot) {
+            // Keep the '-' or '.' sign with next number.
+            startPosition = endPosition;
+        } else {
+            startPosition = endPosition + 1;
+        }
+    }
+}
+
+void PathParser::getPathDataFromString(PathData* data, const char* pathStr, size_t strLen) {
+    if (pathStr == NULL) {
+        return;
+    }
+
+    size_t start = 0;
+    size_t end = 1;
+
+    while (end < strLen) {
+        end = nextStart(pathStr, strLen, end);
+        std::vector<float> points;
+        getFloats(&points, pathStr, start, end);
+        data->verbs.push_back(pathStr[start]);
+        data->verbSizes.push_back(points.size());
+        data->points.insert(data->points.end(), points.begin(), points.end());
+        start = end;
+        end++;
+    }
+
+    if ((end - start) == 1 && pathStr[start] != '\0') {
+        data->verbs.push_back(pathStr[start]);
+        data->verbSizes.push_back(0);
+    }
+
+    int i = 0;
+    while(pathStr[i] != '\0') {
+       i++;
+    }
+
+}
+
+void PathParser::dump(const PathData& data) {
+    // Print out the path data.
+    size_t start = 0;
+    for (size_t i = 0; i < data.verbs.size(); i++) {
+        std::ostringstream os;
+        os << data.verbs[i];
+        for (size_t j = 0; j < data.verbSizes[i]; j++) {
+            os << " " << data.points[start + j];
+        }
+        start += data.verbSizes[i];
+        ALOGD("%s", os.str().c_str());
+    }
+
+    std::ostringstream os;
+    for (size_t i = 0; i < data.points.size(); i++) {
+        os << data.points[i] << ", ";
+    }
+    ALOGD("points are : %s", os.str().c_str());
+}
+
+void PathParser::parseStringForSkPath(SkPath* skPath, const char* pathStr, size_t strLen) {
+    PathData pathData;
+    getPathDataFromString(&pathData, pathStr, strLen);
+    VectorDrawablePath::verbsToPath(skPath, &pathData);
+}
+
+}; // namespace uirenderer
+}; //namespace android
diff --git a/libs/hwui/PathParser.h b/libs/hwui/PathParser.h
new file mode 100644
index 0000000..6dc7ee1
--- /dev/null
+++ b/libs/hwui/PathParser.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2015 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_PATHPARSER_H
+#define ANDROID_HWUI_PATHPARSER_H
+
+#include "VectorDrawablePath.h"
+
+#include <jni.h>
+#include <android/log.h>
+
+namespace android {
+namespace uirenderer {
+
+class PathParser {
+public:
+    static void parseStringForSkPath(SkPath* outPath, const char* pathStr, size_t strLength);
+    static void getPathDataFromString(PathData* outData, const char* pathStr, size_t strLength);
+    static void dump(const PathData& data);
+};
+
+}; // namespace uirenderer
+}; // namespace android
+#endif //ANDROID_HWUI_PATHPARSER_H
diff --git a/libs/hwui/VectorDrawablePath.cpp b/libs/hwui/VectorDrawablePath.cpp
new file mode 100644
index 0000000..115435c
--- /dev/null
+++ b/libs/hwui/VectorDrawablePath.cpp
@@ -0,0 +1,496 @@
+/*
+ * Copyright (C) 2015 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.
+ */
+
+#include "VectorDrawablePath.h"
+
+#include "PathParser.h"
+
+#include <math.h>
+#include <utils/Log.h>
+
+namespace android {
+namespace uirenderer {
+
+class PathResolver {
+public:
+    float currentX = 0;
+    float currentY = 0;
+    float ctrlPointX = 0;
+    float ctrlPointY = 0;
+    float currentSegmentStartX = 0;
+    float currentSegmentStartY = 0;
+    void addCommand(SkPath* outPath, char previousCmd,
+            char cmd, const std::vector<float>* points, size_t start, size_t end);
+};
+
+VectorDrawablePath::VectorDrawablePath(const char* pathStr, size_t strLength) {
+    PathParser::getPathDataFromString(&mData, pathStr, strLength);
+    verbsToPath(&mSkPath, &mData);
+}
+
+VectorDrawablePath::VectorDrawablePath(const PathData& data) {
+    mData = data;
+    // Now we need to construct a path
+    verbsToPath(&mSkPath, &data);
+}
+
+VectorDrawablePath::VectorDrawablePath(const VectorDrawablePath& path) {
+    mData = path.mData;
+    verbsToPath(&mSkPath, &mData);
+}
+
+bool VectorDrawablePath::canMorph(const PathData& morphTo) {
+    if (mData.verbs.size() != morphTo.verbs.size()) {
+        return false;
+    }
+
+    for (unsigned int i = 0; i < mData.verbs.size(); i++) {
+        if (mData.verbs[i] != morphTo.verbs[i]
+                || mData.verbSizes[i] != morphTo.verbSizes[i]) {
+            return false;
+        }
+    }
+    return true;
+}
+
+bool VectorDrawablePath::canMorph(const VectorDrawablePath& path) {
+    return canMorph(path.mData);
+}
+ /**
+ * Convert an array of PathVerb to Path.
+ */
+void VectorDrawablePath::verbsToPath(SkPath* outPath, const PathData* data) {
+    PathResolver resolver;
+    char previousCommand = 'm';
+    size_t start = 0;
+    outPath->reset();
+    for (unsigned int i = 0; i < data->verbs.size(); i++) {
+        size_t verbSize = data->verbSizes[i];
+        resolver.addCommand(outPath, previousCommand, data->verbs[i], &data->points, start,
+                start + verbSize - 1u);
+        previousCommand = data->verbs[i];
+        start += verbSize;
+    }
+}
+
+/**
+ * The current PathVerb will be interpolated between the
+ * <code>nodeFrom</code> and <code>nodeTo</code> according to the
+ * <code>fraction</code>.
+ *
+ * @param nodeFrom The start value as a PathVerb.
+ * @param nodeTo The end value as a PathVerb
+ * @param fraction The fraction to interpolate.
+ */
+void VectorDrawablePath::interpolatePaths(PathData* outData,
+        const PathData* from, const PathData* to, float fraction) {
+    outData->points.resize(from->points.size());
+    outData->verbSizes = from->verbSizes;
+    outData->verbs = from->verbs;
+
+    for (size_t i = 0; i < from->points.size(); i++) {
+        outData->points[i] = from->points[i] * (1 - fraction) + to->points[i] * fraction;
+    }
+}
+
+/**
+ * Converts an arc to cubic Bezier segments and records them in p.
+ *
+ * @param p The target for the cubic Bezier segments
+ * @param cx The x coordinate center of the ellipse
+ * @param cy The y coordinate center of the ellipse
+ * @param a The radius of the ellipse in the horizontal direction
+ * @param b The radius of the ellipse in the vertical direction
+ * @param e1x E(eta1) x coordinate of the starting point of the arc
+ * @param e1y E(eta2) y coordinate of the starting point of the arc
+ * @param theta The angle that the ellipse bounding rectangle makes with horizontal plane
+ * @param start The start angle of the arc on the ellipse
+ * @param sweep The angle (positive or negative) of the sweep of the arc on the ellipse
+ */
+static void arcToBezier(SkPath* p,
+        double cx,
+        double cy,
+        double a,
+        double b,
+        double e1x,
+        double e1y,
+        double theta,
+        double start,
+        double sweep) {
+    // Taken from equations at: http://spaceroots.org/documents/ellipse/node8.html
+    // and http://www.spaceroots.org/documents/ellipse/node22.html
+
+    // Maximum of 45 degrees per cubic Bezier segment
+    int numSegments = ceil(fabs(sweep * 4 / M_PI));
+
+    double eta1 = start;
+    double cosTheta = cos(theta);
+    double sinTheta = sin(theta);
+    double cosEta1 = cos(eta1);
+    double sinEta1 = sin(eta1);
+    double ep1x = (-a * cosTheta * sinEta1) - (b * sinTheta * cosEta1);
+    double ep1y = (-a * sinTheta * sinEta1) + (b * cosTheta * cosEta1);
+
+    double anglePerSegment = sweep / numSegments;
+    for (int i = 0; i < numSegments; i++) {
+        double eta2 = eta1 + anglePerSegment;
+        double sinEta2 = sin(eta2);
+        double cosEta2 = cos(eta2);
+        double e2x = cx + (a * cosTheta * cosEta2) - (b * sinTheta * sinEta2);
+        double e2y = cy + (a * sinTheta * cosEta2) + (b * cosTheta * sinEta2);
+        double ep2x = -a * cosTheta * sinEta2 - b * sinTheta * cosEta2;
+        double ep2y = -a * sinTheta * sinEta2 + b * cosTheta * cosEta2;
+        double tanDiff2 = tan((eta2 - eta1) / 2);
+        double alpha =
+                sin(eta2 - eta1) * (sqrt(4 + (3 * tanDiff2 * tanDiff2)) - 1) / 3;
+        double q1x = e1x + alpha * ep1x;
+        double q1y = e1y + alpha * ep1y;
+        double q2x = e2x - alpha * ep2x;
+        double q2y = e2y - alpha * ep2y;
+
+        p->cubicTo((float) q1x,
+                (float) q1y,
+                (float) q2x,
+                (float) q2y,
+                (float) e2x,
+                (float) e2y);
+        eta1 = eta2;
+        e1x = e2x;
+        e1y = e2y;
+        ep1x = ep2x;
+        ep1y = ep2y;
+    }
+}
+
+inline double toRadians(float theta) { return theta * M_PI / 180;}
+
+static void drawArc(SkPath* p,
+        float x0,
+        float y0,
+        float x1,
+        float y1,
+        float a,
+        float b,
+        float theta,
+        bool isMoreThanHalf,
+        bool isPositiveArc) {
+
+    /* Convert rotation angle from degrees to radians */
+    double thetaD = toRadians(theta);
+    /* Pre-compute rotation matrix entries */
+    double cosTheta = cos(thetaD);
+    double sinTheta = sin(thetaD);
+    /* Transform (x0, y0) and (x1, y1) into unit space */
+    /* using (inverse) rotation, followed by (inverse) scale */
+    double x0p = (x0 * cosTheta + y0 * sinTheta) / a;
+    double y0p = (-x0 * sinTheta + y0 * cosTheta) / b;
+    double x1p = (x1 * cosTheta + y1 * sinTheta) / a;
+    double y1p = (-x1 * sinTheta + y1 * cosTheta) / b;
+
+    /* Compute differences and averages */
+    double dx = x0p - x1p;
+    double dy = y0p - y1p;
+    double xm = (x0p + x1p) / 2;
+    double ym = (y0p + y1p) / 2;
+    /* Solve for intersecting unit circles */
+    double dsq = dx * dx + dy * dy;
+    if (dsq == 0.0) {
+        ALOGW("Points are coincident");
+        return; /* Points are coincident */
+    }
+    double disc = 1.0 / dsq - 1.0 / 4.0;
+    if (disc < 0.0) {
+        ALOGW("Points are too far apart %f", dsq);
+        float adjust = (float) (sqrt(dsq) / 1.99999);
+        drawArc(p, x0, y0, x1, y1, a * adjust,
+                b * adjust, theta, isMoreThanHalf, isPositiveArc);
+        return; /* Points are too far apart */
+    }
+    double s = sqrt(disc);
+    double sdx = s * dx;
+    double sdy = s * dy;
+    double cx;
+    double cy;
+    if (isMoreThanHalf == isPositiveArc) {
+        cx = xm - sdy;
+        cy = ym + sdx;
+    } else {
+        cx = xm + sdy;
+        cy = ym - sdx;
+    }
+
+    double eta0 = atan2((y0p - cy), (x0p - cx));
+
+    double eta1 = atan2((y1p - cy), (x1p - cx));
+
+    double sweep = (eta1 - eta0);
+    if (isPositiveArc != (sweep >= 0)) {
+        if (sweep > 0) {
+            sweep -= 2 * M_PI;
+        } else {
+            sweep += 2 * M_PI;
+        }
+    }
+
+    cx *= a;
+    cy *= b;
+    double tcx = cx;
+    cx = cx * cosTheta - cy * sinTheta;
+    cy = tcx * sinTheta + cy * cosTheta;
+
+    arcToBezier(p, cx, cy, a, b, x0, y0, thetaD, eta0, sweep);
+}
+
+
+void PathResolver::addCommand(SkPath* outPath, char previousCmd,
+        char cmd, const std::vector<float>* points, size_t start, size_t end) {
+
+    int incr = 2;
+    float reflectiveCtrlPointX;
+    float reflectiveCtrlPointY;
+
+    switch (cmd) {
+    case 'z':
+    case 'Z':
+        outPath->close();
+        // Path is closed here, but we need to move the pen to the
+        // closed position. So we cache the segment's starting position,
+        // and restore it here.
+        currentX = currentSegmentStartX;
+        currentY = currentSegmentStartY;
+        ctrlPointX = currentSegmentStartX;
+        ctrlPointY = currentSegmentStartY;
+        outPath->moveTo(currentX, currentY);
+        break;
+    case 'm':
+    case 'M':
+    case 'l':
+    case 'L':
+    case 't':
+    case 'T':
+        incr = 2;
+        break;
+    case 'h':
+    case 'H':
+    case 'v':
+    case 'V':
+        incr = 1;
+        break;
+    case 'c':
+    case 'C':
+        incr = 6;
+        break;
+    case 's':
+    case 'S':
+    case 'q':
+    case 'Q':
+        incr = 4;
+        break;
+    case 'a':
+    case 'A':
+        incr = 7;
+        break;
+    }
+
+    for (unsigned int k = start; k <= end; k += incr) {
+        switch (cmd) {
+        case 'm': // moveto - Start a new sub-path (relative)
+            currentX += points->at(k + 0);
+            currentY += points->at(k + 1);
+            if (k > start) {
+                // According to the spec, if a moveto is followed by multiple
+                // pairs of coordinates, the subsequent pairs are treated as
+                // implicit lineto commands.
+                outPath->rLineTo(points->at(k + 0), points->at(k + 1));
+            } else {
+                outPath->rMoveTo(points->at(k + 0), points->at(k + 1));
+                currentSegmentStartX = currentX;
+                currentSegmentStartY = currentY;
+            }
+            break;
+        case 'M': // moveto - Start a new sub-path
+            currentX = points->at(k + 0);
+            currentY = points->at(k + 1);
+            if (k > start) {
+                // According to the spec, if a moveto is followed by multiple
+                // pairs of coordinates, the subsequent pairs are treated as
+                // implicit lineto commands.
+                outPath->lineTo(points->at(k + 0), points->at(k + 1));
+            } else {
+                outPath->moveTo(points->at(k + 0), points->at(k + 1));
+                currentSegmentStartX = currentX;
+                currentSegmentStartY = currentY;
+            }
+            break;
+        case 'l': // lineto - Draw a line from the current point (relative)
+            outPath->rLineTo(points->at(k + 0), points->at(k + 1));
+            currentX += points->at(k + 0);
+            currentY += points->at(k + 1);
+            break;
+        case 'L': // lineto - Draw a line from the current point
+            outPath->lineTo(points->at(k + 0), points->at(k + 1));
+            currentX = points->at(k + 0);
+            currentY = points->at(k + 1);
+            break;
+        case 'h': // horizontal lineto - Draws a horizontal line (relative)
+            outPath->rLineTo(points->at(k + 0), 0);
+            currentX += points->at(k + 0);
+            break;
+        case 'H': // horizontal lineto - Draws a horizontal line
+            outPath->lineTo(points->at(k + 0), currentY);
+            currentX = points->at(k + 0);
+            break;
+        case 'v': // vertical lineto - Draws a vertical line from the current point (r)
+            outPath->rLineTo(0, points->at(k + 0));
+            currentY += points->at(k + 0);
+            break;
+        case 'V': // vertical lineto - Draws a vertical line from the current point
+            outPath->lineTo(currentX, points->at(k + 0));
+            currentY = points->at(k + 0);
+            break;
+        case 'c': // curveto - Draws a cubic Bézier curve (relative)
+            outPath->rCubicTo(points->at(k + 0), points->at(k + 1), points->at(k + 2), points->at(k + 3),
+                    points->at(k + 4), points->at(k + 5));
+
+            ctrlPointX = currentX + points->at(k + 2);
+            ctrlPointY = currentY + points->at(k + 3);
+            currentX += points->at(k + 4);
+            currentY += points->at(k + 5);
+
+            break;
+        case 'C': // curveto - Draws a cubic Bézier curve
+            outPath->cubicTo(points->at(k + 0), points->at(k + 1), points->at(k + 2), points->at(k + 3),
+                    points->at(k + 4), points->at(k + 5));
+            currentX = points->at(k + 4);
+            currentY = points->at(k + 5);
+            ctrlPointX = points->at(k + 2);
+            ctrlPointY = points->at(k + 3);
+            break;
+        case 's': // smooth curveto - Draws a cubic Bézier curve (reflective cp)
+            reflectiveCtrlPointX = 0;
+            reflectiveCtrlPointY = 0;
+            if (previousCmd == 'c' || previousCmd == 's'
+                    || previousCmd == 'C' || previousCmd == 'S') {
+                reflectiveCtrlPointX = currentX - ctrlPointX;
+                reflectiveCtrlPointY = currentY - ctrlPointY;
+            }
+            outPath->rCubicTo(reflectiveCtrlPointX, reflectiveCtrlPointY,
+                    points->at(k + 0), points->at(k + 1),
+                    points->at(k + 2), points->at(k + 3));
+            ctrlPointX = currentX + points->at(k + 0);
+            ctrlPointY = currentY + points->at(k + 1);
+            currentX += points->at(k + 2);
+            currentY += points->at(k + 3);
+            break;
+        case 'S': // shorthand/smooth curveto Draws a cubic Bézier curve(reflective cp)
+            reflectiveCtrlPointX = currentX;
+            reflectiveCtrlPointY = currentY;
+            if (previousCmd == 'c' || previousCmd == 's'
+                    || previousCmd == 'C' || previousCmd == 'S') {
+                reflectiveCtrlPointX = 2 * currentX - ctrlPointX;
+                reflectiveCtrlPointY = 2 * currentY - ctrlPointY;
+            }
+            outPath->cubicTo(reflectiveCtrlPointX, reflectiveCtrlPointY,
+                    points->at(k + 0), points->at(k + 1), points->at(k + 2), points->at(k + 3));
+            ctrlPointX = points->at(k + 0);
+            ctrlPointY = points->at(k + 1);
+            currentX = points->at(k + 2);
+            currentY = points->at(k + 3);
+            break;
+        case 'q': // Draws a quadratic Bézier (relative)
+            outPath->rQuadTo(points->at(k + 0), points->at(k + 1), points->at(k + 2), points->at(k + 3));
+            ctrlPointX = currentX + points->at(k + 0);
+            ctrlPointY = currentY + points->at(k + 1);
+            currentX += points->at(k + 2);
+            currentY += points->at(k + 3);
+            break;
+        case 'Q': // Draws a quadratic Bézier
+            outPath->quadTo(points->at(k + 0), points->at(k + 1), points->at(k + 2), points->at(k + 3));
+            ctrlPointX = points->at(k + 0);
+            ctrlPointY = points->at(k + 1);
+            currentX = points->at(k + 2);
+            currentY = points->at(k + 3);
+            break;
+        case 't': // Draws a quadratic Bézier curve(reflective control point)(relative)
+            reflectiveCtrlPointX = 0;
+            reflectiveCtrlPointY = 0;
+            if (previousCmd == 'q' || previousCmd == 't'
+                    || previousCmd == 'Q' || previousCmd == 'T') {
+                reflectiveCtrlPointX = currentX - ctrlPointX;
+                reflectiveCtrlPointY = currentY - ctrlPointY;
+            }
+            outPath->rQuadTo(reflectiveCtrlPointX, reflectiveCtrlPointY,
+                    points->at(k + 0), points->at(k + 1));
+            ctrlPointX = currentX + reflectiveCtrlPointX;
+            ctrlPointY = currentY + reflectiveCtrlPointY;
+            currentX += points->at(k + 0);
+            currentY += points->at(k + 1);
+            break;
+        case 'T': // Draws a quadratic Bézier curve (reflective control point)
+            reflectiveCtrlPointX = currentX;
+            reflectiveCtrlPointY = currentY;
+            if (previousCmd == 'q' || previousCmd == 't'
+                    || previousCmd == 'Q' || previousCmd == 'T') {
+                reflectiveCtrlPointX = 2 * currentX - ctrlPointX;
+                reflectiveCtrlPointY = 2 * currentY - ctrlPointY;
+            }
+            outPath->quadTo(reflectiveCtrlPointX, reflectiveCtrlPointY,
+                    points->at(k + 0), points->at(k + 1));
+            ctrlPointX = reflectiveCtrlPointX;
+            ctrlPointY = reflectiveCtrlPointY;
+            currentX = points->at(k + 0);
+            currentY = points->at(k + 1);
+            break;
+        case 'a': // Draws an elliptical arc
+            // (rx ry x-axis-rotation large-arc-flag sweep-flag x y)
+            drawArc(outPath,
+                    currentX,
+                    currentY,
+                    points->at(k + 5) + currentX,
+                    points->at(k + 6) + currentY,
+                    points->at(k + 0),
+                    points->at(k + 1),
+                    points->at(k + 2),
+                    points->at(k + 3) != 0,
+                    points->at(k + 4) != 0);
+            currentX += points->at(k + 5);
+            currentY += points->at(k + 6);
+            ctrlPointX = currentX;
+            ctrlPointY = currentY;
+            break;
+        case 'A': // Draws an elliptical arc
+            drawArc(outPath,
+                    currentX,
+                    currentY,
+                    points->at(k + 5),
+                    points->at(k + 6),
+                    points->at(k + 0),
+                    points->at(k + 1),
+                    points->at(k + 2),
+                    points->at(k + 3) != 0,
+                    points->at(k + 4) != 0);
+            currentX = points->at(k + 5);
+            currentY = points->at(k + 6);
+            ctrlPointX = currentX;
+            ctrlPointY = currentY;
+            break;
+        }
+        previousCmd = cmd;
+    }
+}
+
+}; // namespace uirenderer
+}; // namespace android
diff --git a/libs/hwui/VectorDrawablePath.h b/libs/hwui/VectorDrawablePath.h
new file mode 100644
index 0000000..40ce986
--- /dev/null
+++ b/libs/hwui/VectorDrawablePath.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2015 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_VPATH_H
+#define ANDROID_HWUI_VPATH_H
+
+#include "SkPath.h"
+#include <vector>
+
+namespace android {
+namespace uirenderer {
+
+
+
+struct PathData {
+    // TODO: Try using FatVector instead of std::vector and do a micro benchmark on the performance
+    // difference.
+    std::vector<char> verbs;
+    std::vector<size_t> verbSizes;
+    std::vector<float> points;
+    bool operator== (const PathData& data) const {
+        return verbs == data.verbs && verbSizes == data.verbSizes && points == data.points;
+    }
+
+};
+
+class VectorDrawablePath {
+public:
+    VectorDrawablePath(const PathData& nodes);
+    VectorDrawablePath(const VectorDrawablePath& path);
+    VectorDrawablePath(const char* path, size_t strLength);
+    bool canMorph(const PathData& path);
+    bool canMorph(const VectorDrawablePath& path);
+    static void verbsToPath(SkPath* outPath, const PathData* data);
+    static void interpolatePaths(PathData* outPathData, const PathData* from, const PathData* to,
+            float fraction);
+private:
+    PathData mData;
+    SkPath mSkPath;
+};
+
+} // namespace uirenderer
+} // namespace android
+
+#endif // ANDROID_HWUI_VPATH_H
diff --git a/libs/hwui/unit_tests/PathParserTests.cpp b/libs/hwui/unit_tests/PathParserTests.cpp
new file mode 100644
index 0000000..244bd6c
--- /dev/null
+++ b/libs/hwui/unit_tests/PathParserTests.cpp
@@ -0,0 +1,172 @@
+/*
+ * Copyright (C) 2015 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.
+ */
+
+#include <gtest/gtest.h>
+
+#include "PathParser.h"
+#include "VectorDrawablePath.h"
+
+#include <functional>
+
+namespace android {
+namespace uirenderer {
+
+struct TestData {
+    const char* pathString;
+    const PathData pathData;
+    const std::function<void(SkPath*)> skPathLamda;
+};
+
+static TestData testData1 {
+    // Path
+    "M2.000000,22.000000l20.000000,0.000000 1e0-2e3z",
+    {
+        // Verbs
+        {'M', 'l', 'z'},
+        // Verb sizes
+        {2, 4, 0},
+        // Points
+        {2, 22, 20, 0,  1, -2000},
+    },
+    [](SkPath* outPath) {
+        outPath->moveTo(2, 22);
+        outPath->rLineTo(20, 0);
+        outPath->rLineTo(1, -2000);
+        outPath->close();
+        outPath->moveTo(2, 22);
+    }
+};
+
+static TestData testData2 {
+    // Path
+    "M 1 1 m 2 2, l 3 3 L 3 3 H 4 h4 V5 v5, Q6 6 6 6 q 6 6 6 6t 7 7 T 7 7 C 8 8 8 8 8 8 c 8 8 8 8 8 8 S 9 9 9 9 s 9 9 9 9 A 10 10 0 1 1 10 10 a 10 10 0 1 1 10 10",
+    {
+        // Verbs
+        {'M', 'm', 'l', 'L', 'H', 'h', 'V', 'v', 'Q', 'q', 't', 'T', 'C', 'c', 'S', 's', 'A', 'a'},
+        // VerbSizes
+        {2, 2, 2, 2, 1, 1, 1, 1, 4, 4, 2, 2, 6, 6, 4, 4, 7, 7},
+        // Points
+        {1.0, 1.0, 2.0, 2.0, 3.0, 3.0, 3.0, 3.0, 4.0, 4.0, 5.0, 5.0, 6.0, 6.0, 6.0, 6.0, 6.0, 6.0, 6.0, 6.0, 7.0, 7.0, 7.0, 7.0, 8.0, 8.0, 8.0, 8.0, 8.0, 8.0, 8.0, 8.0, 8.0, 8.0, 8.0, 8.0, 9.0, 9.0, 9.0, 9.0, 9.0, 9.0, 9.0, 9.0, 10.0, 10.0, 0.0, 1.0, 1.0, 10.0, 10.0, 10.0, 10.0, 0.0, 1.0, 1.0, 10.0, 10.0, }
+    },
+    [](SkPath* outPath) {
+        outPath->moveTo(1.0, 1.0);
+        outPath->rMoveTo(2.0, 2.0);
+        outPath->rLineTo(3.0, 3.0);
+        outPath->lineTo(3.0, 3.0);
+        outPath->lineTo(4.0, 3.0);
+        outPath->rLineTo(4.0, 0);
+        outPath->lineTo(8.0, 5.0);
+        outPath->rLineTo(0, 5.0);
+        outPath->quadTo(6.0, 6.0, 6.0, 6.0);
+        outPath->rQuadTo(6.0, 6.0, 6.0, 6.0);
+        outPath->rQuadTo(0.0, 0.0, 7.0, 7.0);
+        outPath->quadTo(26.0, 26.0, 7.0, 7.0);
+        outPath->cubicTo(8.0, 8.0, 8.0, 8.0, 8.0, 8.0);
+        outPath->rCubicTo(8.0, 8.0, 8.0, 8.0, 8.0, 8.0);
+        outPath->cubicTo(16.0, 16.0, 9.0, 9.0, 9.0, 9.0);
+        outPath->rCubicTo(0.0, 0.0, 9.0, 9.0, 9.0, 9.0);
+        outPath->cubicTo(18.447775037328352, 20.404243860300607, 17.998389141249767, 22.8911717921705, 16.737515350332117, 24.986664170401575);
+        outPath->cubicTo(15.476641559414468, 27.08215654863265, 13.489843598291483, 28.644011882390082, 11.155893964798905, 29.37447073281729);
+        outPath->cubicTo(8.821944331306327, 30.1049295832445, 6.299226382436471, 29.954422532383525, 4.0686829203897235, 28.951642951534332);
+        outPath->cubicTo(1.838139458342976, 27.94886337068514, 0.05113662931485696, 26.161860541657013, -0.9516429515343354, 23.931317079610267);
+        outPath->cubicTo(-1.9544225323835278, 21.70077361756352, -2.1049295832444987, 19.178055668693663, -1.37447073281729, 16.844106035201087);
+        outPath->cubicTo(-0.6440118823900814, 14.51015640170851, 0.9178434513673546, 12.523358440585524, 3.0133358295984305, 11.262484649667876);
+        outPath->cubicTo(5.108828207829506, 10.001610858750228, 7.5957561396993984, 9.552224962671648, 10.000000000000005, 10.0);
+        outPath->cubicTo(10.0, 7.348852265086975, 11.054287646850167, 4.803576729418881, 12.928932188134523, 2.9289321881345254);
+        outPath->cubicTo(14.803576729418879, 1.0542876468501696, 17.348852265086972, 4.870079381441987E-16, 19.999999999999996, 0.0);
+        outPath->cubicTo(22.65114773491302, -4.870079381441987E-16, 25.19642327058112, 1.0542876468501678, 27.071067811865476, 2.9289321881345227);
+        outPath->cubicTo(28.94571235314983, 4.803576729418878, 30.0, 7.348852265086974, 30.0, 9.999999999999998);
+        outPath->cubicTo(30.0, 12.651147734913023, 28.94571235314983, 15.19642327058112, 27.071067811865476, 17.071067811865476);
+        outPath->cubicTo(25.19642327058112, 18.94571235314983, 22.651147734913028, 20.0, 20.000000000000004, 20.0);
+    }
+};
+
+static TestData testData3 {
+    // Path
+    "M5.3,13.2c-0.1,0.0 -0.3,0.0 -0.4,-0.1c-0.3,-0.2 -0.4,-0.7 -0.2,-1.0c1.3,-1.9 2.9,-3.4 4.9,-4.5c4.1,-2.2 9.3,-2.2 13.4,0.0c1.9,1.1 3.6,2.5 4.9,4.4c0.2,0.3 0.1,0.8 -0.2,1.0c-0.3,0.2 -0.8,0.1 -1.0,-0.2c-1.2,-1.7 -2.6,-3.0 -4.3,-4.0c-3.7,-2.0 -8.3,-2.0 -12.0,0.0c-1.7,0.9 -3.2,2.3 -4.3,4.0C5.7,13.1 5.5,13.2 5.3,13.2z",
+    {
+        // Verbs
+        {'M', 'c', 'c', 'c', 'c', 'c', 'c', 'c', 'c', 'c', 'c', 'C', 'z'},
+        // Verb sizes
+        {2, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 0},
+        // Points
+        {5.3, 13.2, -0.1, 0, -0.3, 0, -0.4, -0.1, -0.3, -0.2, -0.4, -0.7, -0.2, -1, 1.3, -1.9, 2.9, -3.4, 4.9, -4.5, 4.1, -2.2, 9.3, -2.2, 13.4, 0, 1.9, 1.1, 3.6, 2.5, 4.9, 4.4, 0.2, 0.3, 0.1, 0.8, -0.2, 1, -0.3, 0.2, -0.8, 0.1, -1, -0.2, -1.2, -1.7, -2.6, -3, -4.3, -4, -3.7, -2, -8.3, -2, -12, 0, -1.7, 0.9, -3.2, 2.3, -4.3, 4, 5.7, 13.1, 5.5, 13.2, 5.3, 13.2},
+    },
+    [](SkPath* outPath) {
+        outPath->moveTo(5.3, 13.2);
+        outPath->rCubicTo(-0.1, 0.0, -0.3, 0.0, -0.4, -0.1);
+        outPath->rCubicTo(-0.3, -0.2, -0.4, -0.7, -0.2, -1.0);
+        outPath->rCubicTo(1.3, -1.9, 2.9, -3.4, 4.9, -4.5);
+        outPath->rCubicTo(4.1, -2.2, 9.3, -2.2, 13.4, 0.0);
+        outPath->rCubicTo(1.9, 1.1, 3.6, 2.5, 4.9, 4.4);
+        outPath->rCubicTo(0.2, 0.3, 0.1, 0.8, -0.2, 1.0);
+        outPath->rCubicTo(-0.3, 0.2, -0.8, 0.1, -1.0, -0.2);
+        outPath->rCubicTo(-1.2, -1.7, -2.6, -3.0, -4.3, -4.0);
+        outPath->rCubicTo(-3.7, -2.0, -8.3, -2.0, -12.0, 0.0);
+        outPath->rCubicTo(-1.7, 0.9, -3.2, 2.3, -4.3, 4.0);
+        outPath->cubicTo(5.7, 13.1, 5.5, 13.2, 5.3, 13.2);
+        outPath->close();
+        outPath->moveTo(5.3, 13.2);
+    }
+};
+
+static TestData testData4 {
+    // Path
+    "l0.0.0.5.0.0.5-0.5.0.0-.5z",
+    {
+        // Verbs
+        {'l', 'z'},
+        // Verb sizes
+        {10, 0},
+        // Points
+        {0, 0, 0.5, 0, 0, 0.5, -0.5, 0, 0, -0.5},
+    },
+    [](SkPath* outPath) {
+        outPath->rLineTo(0.0, 0.0);
+        outPath->rLineTo(0.5, 0.0);
+        outPath->rLineTo(0.0, 0.5);
+        outPath->rLineTo(-0.5, 0.0);
+        outPath->rLineTo(0.0, -0.5);
+        outPath->close();
+        outPath->moveTo(0.0, 0.0);
+    }
+};
+
+const static TestData testDataSet[] = {testData1, testData2, testData3, testData4};
+
+TEST(PathPaser, parseString) {
+
+    for (int i = 0; i < 4; i++) {
+        // Test generated path data against the given data.
+        PathData pathData;
+        TestData testData = testDataSet[i];
+        size_t length = strlen(testData.pathString);
+        PathParser::getPathDataFromString(&pathData, testData.pathString, length);
+        PathParser::dump(pathData);
+        EXPECT_EQ(testData.pathData, pathData);
+
+        // Test SkPath generated
+        SkPath expectedPath;
+        testData.skPathLamda(&expectedPath);
+        SkPath actualPath;
+        VectorDrawablePath::verbsToPath(&actualPath, &pathData);
+        EXPECT_EQ(expectedPath, actualPath);
+    }
+
+}
+
+}; // namespace uirenderer
+}; // namespace android
diff --git a/libs/hwui/utils/FatVector.h b/libs/hwui/utils/FatVector.h
index 315c249..93d37c2 100644
--- a/libs/hwui/utils/FatVector.h
+++ b/libs/hwui/utils/FatVector.h
@@ -29,6 +29,7 @@
 #include "utils/Macros.h"
 
 #include <stddef.h>
+#include <stdlib.h>
 #include <type_traits>
 #include <utils/Log.h>
 
@@ -95,6 +96,7 @@
     FatVector(size_t capacity) : FatVector() {
         this->resize(capacity);
     }
+
 private:
     typename InlineStdAllocator<T, SIZE>::Allocation mAllocation;
 };