Added missing static methods to Matrix2f for consistency. Cleaned up handling of src == dest aliasing

src/java/org/lwjgl/util/vector/Matrix2f.java

@@ -147,26 +147,15 @@ public class Matrix2f extends Matrix implements Serializable {
 	 * @return the destination matrix
 	 */
 	public static Matrix2f add(Matrix2f left, Matrix2f right, Matrix2f dest) {
-		
-		Matrix2f temp = null;
-		
 		if (dest == null)
 			dest = new Matrix2f();
-		else if (dest == left || dest == right) {
-			temp = dest;
-			dest = new Matrix2f();
-		}
 			
 		dest.m00 = left.m00 + right.m00;
 		dest.m01 = left.m01 + right.m01;
 		dest.m10 = left.m10 + right.m10;
 		dest.m11 = left.m11 + right.m11;
 		
-		if (temp != null) {
+		return dest;		
-			temp.load(dest);
-			return temp;
-		} else
-			return dest;		
 	} 
 
 	/**
@@ -177,26 +166,15 @@ public class Matrix2f extends Matrix implements Serializable {
 	 * @return the destination matrix
 	 */
 	public static Matrix2f sub(Matrix2f left, Matrix2f right, Matrix2f dest) {
-		
-		Matrix2f temp = null;
-		
 		if (dest == null)
 			dest = new Matrix2f();
-		else if (dest == left || dest == right) {
-			temp = dest;
-			dest = new Matrix2f();
-		}
 			
 		dest.m00 = left.m00 - right.m00;
 		dest.m01 = left.m01 - right.m01;
 		dest.m10 = left.m10 - right.m10;
 		dest.m11 = left.m11 - right.m11;
 		
-		if (temp != null) {
+		return dest;		
-			temp.load(dest);
-			return temp;
-		} else
-			return dest;		
 	} 
 
 	/**
@@ -207,26 +185,20 @@ public class Matrix2f extends Matrix implements Serializable {
 	 * @return the destination matrix
 	 */
 	public static Matrix2f mul(Matrix2f left, Matrix2f right, Matrix2f dest) {
-		
-		Matrix2f temp = null;
-		
 		if (dest == null)
 			dest = new Matrix2f();
-		else if (dest == left || dest == right) {
-			temp = dest;
-			dest = new Matrix2f();
-		}
 			
-		dest.m00 = left.m00 * right.m00 + left.m10 * right.m01;
+		float m00 = left.m00 * right.m00 + left.m10 * right.m01;
-		dest.m01 = left.m01 * right.m00 + left.m11 * right.m01;
+		float m01 = left.m01 * right.m00 + left.m11 * right.m01;
-		dest.m10 = left.m00 * right.m10 + left.m10 * right.m11;
+		float m10 = left.m00 * right.m10 + left.m10 * right.m11;
-		dest.m11 = left.m01 * right.m10 + left.m11 * right.m11;
+		float m11 = left.m01 * right.m10 + left.m11 * right.m11;
+		
+		dest.m00 = m00;
+		dest.m01 = m01;
+		dest.m10 = m10;
+		dest.m11 = m11;
 			
-		if (temp != null) {
+		return dest;		
-			temp.load(dest);
-			return temp;
-		} else
-			return dest;		
 	}
 	
 	/**
@@ -238,24 +210,16 @@ public class Matrix2f extends Matrix implements Serializable {
 	 * @return the destination vector
 	 */
 	public static Vector2f transform(Matrix2f left, Vector2f right, Vector2f dest) {
-		
-		Vector2f temp = null;
-		
 		if (dest == null)
 			dest = new Vector2f();
-		else if (dest == right) {
-			temp = dest;
-			dest = new Vector2f();
-		}
 			
-		dest.x = left.m00 * right.x + left.m10 * right.y;
+		float x = left.m00 * right.x + left.m10 * right.y;
-		dest.y = left.m01 * right.x + left.m11 * right.y;			
+		float y = left.m01 * right.x + left.m11 * right.y;
+		
+		dest.x = x;
+		dest.y = y;
 
-		if (temp != null) {
+		return dest;		
-			temp.set(dest);
-			return temp;
-		} else
-			return dest;		
 	}
 	
 	/**
@@ -263,12 +227,7 @@ public class Matrix2f extends Matrix implements Serializable {
 	 * @return this
 	 */
 	public Matrix transpose() {
-		float temp;
+		return transpose(this);
-		
-		temp = m01;
-		m01 = m10;
-		m10 = temp;
-		return this;
 	}
 	
 	/**
@@ -277,27 +236,45 @@ public class Matrix2f extends Matrix implements Serializable {
 	 * @return the transposed matrix
 	 */
 	public Matrix2f transpose(Matrix2f dest) {
-		
+		return transpose(this, dest);
+	}	
+
+	/**
+	 * Transpose source matrix and place the result in dest matrix.
+	 * @param src The source matrix or null if a new matrix is to be created
+	 * @param dest The destination matrix or null if a new matrix is to be created
+	 * @return the transposed matrix
+	 */
+	public static Matrix2f transpose(Matrix2f src, Matrix2f dest) {
 		if (dest == null)
 			dest = new Matrix2f();
-			
+
-		if (dest == this)
+		float m01 = src.m10;
-			transpose();
+		float m10 = src.m01;
-		else {
+
-			dest.m01 = m10;
+		dest.m01 = m01;
-			dest.m10 = m01;
+		dest.m10 = m10;
-		}
 			
 		return dest;
-	}	
+	}
 
 	/**
 	 * Invert this matrix
 	 * @return this if successful, null otherwise
 	 */
-	public Matrix invert() 
+	public Matrix invert() {
-	{
+		return invert(this, this);
-		
+	}
+	
+	/**
+	 * Invert the source matrix and place the result in the dest matrix.
+	 * @param src The source matrix to be inverted
+	 * @param dest The destination matrix or null if a new matrix is to be created
+	 * @return The inverted matrix, or null if source can't be reverted.
+	 */
+	public Matrix2f invert(Matrix2f src, Matrix2f dest) {
+		if (dest == null)
+			dest = new Matrix2f();
 		/*
 		 *inv(A) = 1/det(A) * adj(A);
 		 */
@@ -305,18 +282,18 @@ public class Matrix2f extends Matrix implements Serializable {
 		float determinant = determinant();
 		if (determinant != 0) {
 			float determinant_inv = 1f/determinant;
-			float t00 =  m11*determinant_inv;
+			float t00 =  src.m11*determinant_inv;
-			float t01 = -m01*determinant_inv;
+			float t01 = -src.m01*determinant_inv;
-			float t11 =  m00*determinant_inv;
+			float t11 =  src.m00*determinant_inv;
-			float t10 = -m10*determinant_inv;
+			float t10 = -src.m10*determinant_inv;
 		
-			m00 = t00;
+			dest.m00 = t00;
-			m01 = t01;
+			dest.m01 = t01;
-			m10 = t10;
+			dest.m10 = t10;
-			m11 = t11;
+			dest.m11 = t11;
-			return this;
+			return dest;
 		} else
-		 	return null;
+			return null;
 	}
 
 	/**
@@ -334,13 +311,7 @@ public class Matrix2f extends Matrix implements Serializable {
 	 * @return this
 	 */
 	public Matrix negate() {
-		
+		return negate(this);
-		m00 = -m00;
-		m01 = -m01;
-		m10 = -m10;
-		m11 = -m11;
-		
-		return this;
 	}
 	
 	/**
@@ -349,28 +320,46 @@ public class Matrix2f extends Matrix implements Serializable {
 	 * @return the negated matrix
 	 */
 	public Matrix2f negate(Matrix2f dest) {
-		
+		return negate(this, this);
+	}
+	
+	/**
+	 * Negate src matrix and stash the result in dest matrix.
+	 * @param src The source matrix to be negated
+	 * @param dest The destination matrix, or null if a new matrix is to be created
+	 * @return the negated matrix
+	 */
+	public static Matrix2f negate(Matrix2f src, Matrix2f dest) {
 		if (dest == null)
 			dest = new Matrix2f();
 		
-		dest.m00 = -m00;
+		dest.m00 = -src.m00;
-		dest.m01 = -m01;
+		dest.m01 = -src.m01;
-		dest.m10 = -m10;
+		dest.m10 = -src.m10;
-		dest.m11 = -m11;
+		dest.m11 = -src.m11;
 		
 		return dest;
 	}
-	
+
 	/**
 	 * Set this matrix to be the identity matrix.
 	 * @return this
 	 */
 	public Matrix setIdentity() {
-		m00 = 1.0f;
+		return setIdentity(this);
-		m01 = 0.0f;
+	}
-		m10 = 0.0f;
+
-		m11 = 1.0f;
+	/**
-		return this;
+	 * Set the ssrc matrix to be the identity matrix.
+	 * @param src The matrix to set to the identity.
+	 * @return The source matrix
+	 */
+	public static Matrix2f setIdentity(Matrix2f src) {
+		src.m00 = 1.0f;
+		src.m01 = 0.0f;
+		src.m10 = 0.0f;
+		src.m11 = 1.0f;
+		return src;
 	}
 	
 	/**
@@ -378,11 +367,15 @@ public class Matrix2f extends Matrix implements Serializable {
 	 * @return this
 	 */
 	public Matrix setZero() {
-		m00 = 0.0f;
+		return setZero(this);
-		m01 = 0.0f;
+	}
-		m10 = 0.0f;
+
-		m11 = 0.0f;
+	public static Matrix2f setZero(Matrix2f src) {
-		return this;
+		src.m00 = 0.0f;
+		src.m01 = 0.0f;
+		src.m10 = 0.0f;
+		src.m11 = 0.0f;
+		return src;
 	}
 	
 	/* (non-Javadoc)
@@ -391,5 +384,4 @@ public class Matrix2f extends Matrix implements Serializable {
 	public float determinant() {
 		return m00 * m11 - m01*m10;
 	}
-
 }