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Change-Id: I3dfea7d83bf8525efda59cef6fafa854b5aa9fe3
diff --git a/graphics/java/android/renderscript/Matrix4f.java b/graphics/java/android/renderscript/Matrix4f.java
index ec07cd5..2afd72e 100644
--- a/graphics/java/android/renderscript/Matrix4f.java
+++ b/graphics/java/android/renderscript/Matrix4f.java
@@ -26,28 +26,61 @@
**/
public class Matrix4f {
+ /**
+ * Creates a new identity 4x4 matrix
+ */
public Matrix4f() {
mMat = new float[16];
loadIdentity();
}
+ /**
+ * Creates a new matrix and sets its values from the given
+ * parameter
+ *
+ * @param dataArray values to set the matrix to, must be 16
+ * floats long
+ */
public Matrix4f(float[] dataArray) {
mMat = new float[16];
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*4 + 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*4 + j] = v;
}
+ /**
+ * Sets the matrix values to identity
+ */
public void loadIdentity() {
mMat[0] = 1;
mMat[1] = 0;
@@ -70,10 +103,24 @@
mMat[15] = 1;
}
+ /**
+ * Sets the values of the matrix to those of the parameter
+ *
+ * @param src matrix to load the values from
+ */
public void load(Matrix4f src) {
System.arraycopy(src.getArray(), 0, mMat, 0, mMat.length);
}
+ /**
+ * Sets current values to be a rotation matrix of certain angle
+ * about a given axis
+ *
+ * @param rot angle of rotation
+ * @param x rotation axis x
+ * @param y rotation axis y
+ * @param z rotation axis z
+ */
public void loadRotate(float rot, float x, float y, float z) {
float c, s;
mMat[3] = 0;
@@ -112,6 +159,13 @@
mMat[10] = z*z*nc + c;
}
+ /**
+ * Sets current values to be a scale matrix of given dimensions
+ *
+ * @param x scale component x
+ * @param y scale component y
+ * @param z scale component z
+ */
public void loadScale(float x, float y, float z) {
loadIdentity();
mMat[0] = x;
@@ -119,6 +173,14 @@
mMat[10] = z;
}
+ /**
+ * Sets current values to be a translation matrix of given
+ * dimensions
+ *
+ * @param x translation component x
+ * @param y translation component y
+ * @param z translation component z
+ */
public void loadTranslate(float x, float y, float z) {
loadIdentity();
mMat[12] = x;
@@ -126,6 +188,13 @@
mMat[14] = z;
}
+ /**
+ * 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(Matrix4f lhs, Matrix4f rhs) {
for (int i=0 ; i<4 ; i++) {
float ri0 = 0;
@@ -146,6 +215,16 @@
}
}
+ /**
+ * Set current values to be an orthographic projection matrix
+ *
+ * @param l location of the left vertical clipping plane
+ * @param r location of the right vertical clipping plane
+ * @param b location of the bottom horizontal clipping plane
+ * @param t location of the top horizontal clipping plane
+ * @param n location of the near clipping plane
+ * @param f location of the far clipping plane
+ */
public void loadOrtho(float l, float r, float b, float t, float n, float f) {
loadIdentity();
mMat[0] = 2 / (r - l);
@@ -156,10 +235,31 @@
mMat[14]= -(f + n) / (f - n);
}
+ /**
+ * Set current values to be an orthographic projection matrix
+ * with the right and bottom clipping planes set to the given
+ * values. Left and top clipping planes are set to 0. Near and
+ * far are set to -1, 1 respectively
+ *
+ * @param w location of the right vertical clipping plane
+ * @param h location of the bottom horizontal clipping plane
+ *
+ */
public void loadOrthoWindow(int w, int h) {
loadOrtho(0,w, h,0, -1,1);
}
+ /**
+ * Sets current values to be a perspective projection matrix
+ *
+ * @param l location of the left vertical clipping plane
+ * @param r location of the right vertical clipping plane
+ * @param b location of the bottom horizontal clipping plane
+ * @param t location of the top horizontal clipping plane
+ * @param n location of the near clipping plane, must be positive
+ * @param f location of the far clipping plane, must be positive
+ *
+ */
public void loadFrustum(float l, float r, float b, float t, float n, float f) {
loadIdentity();
mMat[0] = 2 * n / (r - l);
@@ -172,6 +272,14 @@
mMat[15]= 0;
}
+ /**
+ * Sets current values to be a perspective projection matrix
+ *
+ * @param fovy vertical field of view angle in degrees
+ * @param aspect aspect ratio of the screen
+ * @param near near cliping plane, must be positive
+ * @param far far clipping plane, must be positive
+ */
public void loadPerspective(float fovy, float aspect, float near, float far) {
float top = near * (float)Math.tan((float) (fovy * Math.PI / 360.0f));
float bottom = -top;
@@ -180,6 +288,14 @@
loadFrustum(left, right, bottom, top, near, far);
}
+ /**
+ * Helper function to set the current values to a perspective
+ * projection matrix with aspect ratio defined by the parameters
+ * and (near, far), (bottom, top) mapping to (-1, 1) at z = 0
+ *
+ * @param w screen width
+ * @param h screen height
+ */
public void loadProjectionNormalized(int w, int h) {
// range -1,1 in the narrow axis at z = 0.
Matrix4f m1 = new Matrix4f();
@@ -205,22 +321,53 @@
load(m1);
}
-
+ /**
+ * Post-multiplies the current matrix by a given parameter
+ *
+ * @param rhs right hand side to multiply by
+ */
public void multiply(Matrix4f rhs) {
Matrix4f tmp = new Matrix4f();
tmp.loadMultiply(this, rhs);
load(tmp);
}
+ /**
+ * Modifies the current matrix by post-multiplying it with a
+ * rotation matrix of certain angle about a given axis
+ *
+ * @param rot angle of rotation
+ * @param x rotation axis x
+ * @param y rotation axis y
+ * @param z rotation axis z
+ */
public void rotate(float rot, float x, float y, float z) {
Matrix4f tmp = new Matrix4f();
tmp.loadRotate(rot, x, y, z);
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
+ * @param z scale component z
+ */
public void scale(float x, float y, float z) {
Matrix4f tmp = new Matrix4f();
tmp.loadScale(x, y, z);
multiply(tmp);
}
+
+ /**
+ * Modifies the current matrix by post-multiplying it with a
+ * translation matrix of given dimensions
+ *
+ * @param x translation component x
+ * @param y translation component y
+ * @param z translation component z
+ */
public void translate(float x, float y, float z) {
Matrix4f tmp = new Matrix4f();
tmp.loadTranslate(x, y, z);
@@ -245,6 +392,9 @@
return cofactor;
}
+ /**
+ * Sets the current matrix to its inverse
+ */
public boolean inverse() {
Matrix4f result = new Matrix4f();
@@ -271,6 +421,9 @@
return true;
}
+ /**
+ * Sets the current matrix to its inverse transpose
+ */
public boolean inverseTranspose() {
Matrix4f result = new Matrix4f();
@@ -296,6 +449,9 @@
return true;
}
+ /**
+ * Sets the current matrix to its transpose
+ */
public void transpose() {
for(int i = 0; i < 3; ++i) {
for(int j = i + 1; j < 4; ++j) {
@@ -308,8 +464,3 @@
final float[] mMat;
}
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