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Change-Id: I3dfea7d83bf8525efda59cef6fafa854b5aa9fe3

1 files changed, 78 insertions, 0 deletions

diff --git a/graphics/java/android/renderscript/Matrix2f.java b/graphics/java/android/renderscript/Matrix2f.java
index 2fffe8ceebb1..c9a0ea8ab04b 100644
--- a/graphics/java/android/renderscript/Matrix2f.java
+++ b/graphics/java/android/renderscript/Matrix2f.java
@@ -26,28 +26,61 @@ import android.util.Log;
  **/
 public class Matrix2f {
 
+    /**
+    * Creates a new identity 2x2 matrix
+    */
     public Matrix2f() {
         mMat = new float[4];
         loadIdentity();
     }
 
+    /**
+    * Creates a new matrix and sets its values from the given
+    * parameter
+    *
+    * @param dataArray values to set the matrix to, must be 4
+    *                  floats long
+    */
     public Matrix2f(float[] dataArray) {
         mMat = new float[2];
         System.arraycopy(dataArray, 0, mMat, 0, mMat.length);
     }
 
+    /**
+    * Return a reference to the internal array representing matrix
+    * values. Modifying this array will also change the matrix
+    *
+    * @return internal array representing the matrix
+    */
     public float[] getArray() {
         return mMat;
     }
 
+    /**
+    * Returns the value for a given row and column
+    *
+    * @param i row of the value to return
+    * @param j column of the value to return
+    *
+    * @return value in the ith row and jth column
+    */
     public float get(int i, int j) {
         return mMat[i*2 + j];
     }
 
+    /**
+    * Sets the value for a given row and column
+    *
+    * @param i row of the value to set
+    * @param j column of the value to set
+    */
     public void set(int i, int j, float v) {
         mMat[i*2 + j] = v;
     }
 
+    /**
+    * Sets the matrix values to identity
+    */
     public void loadIdentity() {
         mMat[0] = 1;
         mMat[1] = 0;
@@ -56,10 +89,20 @@ public class Matrix2f {
         mMat[3] = 1;
     }
 
+    /**
+    * Sets the values of the matrix to those of the parameter
+    *
+    * @param src matrix to load the values from
+    */
     public void load(Matrix2f src) {
         System.arraycopy(src.getArray(), 0, mMat, 0, mMat.length);
     }
 
+    /**
+    * Sets current values to be a rotation matrix of given angle
+    *
+    * @param rot rotation angle
+    */
     public void loadRotate(float rot) {
         float c, s;
         rot *= (float)(java.lang.Math.PI / 180.0f);
@@ -71,11 +114,25 @@ public class Matrix2f {
         mMat[3] = c;
     }
 
+    /**
+    * Sets current values to be a scale matrix of given dimensions
+    *
+    * @param x scale component x
+    * @param y scale component y
+    */
     public void loadScale(float x, float y) {
         loadIdentity();
         mMat[0] = x;
         mMat[3] = y;
     }
+
+    /**
+    * Sets current values to be the result of multiplying two given
+    * matrices
+    *
+    * @param lhs left hand side matrix
+    * @param rhs right hand side matrix
+    */
     public void loadMultiply(Matrix2f lhs, Matrix2f rhs) {
         for (int i=0 ; i<2 ; i++) {
             float ri0 = 0;
@@ -90,21 +147,42 @@ public class Matrix2f {
         }
     }
 
+    /**
+    * Post-multiplies the current matrix by a given parameter
+    *
+    * @param rhs right hand side to multiply by
+    */
     public void multiply(Matrix2f rhs) {
         Matrix2f tmp = new Matrix2f();
         tmp.loadMultiply(this, rhs);
         load(tmp);
     }
+    /**
+    * Modifies the current matrix by post-multiplying it with a
+    * rotation matrix of given angle
+    *
+    * @param rot angle of rotation
+    */
     public void rotate(float rot) {
         Matrix2f tmp = new Matrix2f();
         tmp.loadRotate(rot);
         multiply(tmp);
     }
+    /**
+    * Modifies the current matrix by post-multiplying it with a
+    * scale matrix of given dimensions
+    *
+    * @param x scale component x
+    * @param y scale component y
+    */
     public void scale(float x, float y) {
         Matrix2f tmp = new Matrix2f();
         tmp.loadScale(x, y);
         multiply(tmp);
     }
+    /**
+    * Sets the current matrix to its transpose
+    */
     public void transpose() {
         float temp = mMat[1];
         mMat[1] = mMat[2];