- Added private classes for more convenient coordinate and vector

  transformations

4 files changed, 198 insertions, 0 deletions

diff --git a/src/math/rotation.php b/src/math/rotation.php
new file mode 100644
index 0000000..13583df
--- /dev/null
+++ b/src/math/rotation.php
@@ -0,0 +1,67 @@
+<?php
+/**
+ * File containing the ezcGraphRotation class
+ *
+ * @package Graph
+ * @version //autogentag//
+ * @copyright Copyright (C) 2005-2007 eZ systems as. All rights reserved.
+ * @license http://ez.no/licenses/new_bsd New BSD License
+ * @access private
+ */
+/**
+ * Class to create rotation matrices from given rotation and center point
+ *
+ * @package Graph
+ * @access private
+ */
+class ezcGraphRotation extends ezcGraphTransformation
+{
+    /**
+     * Rotation in degrees
+     * 
+     * @var float
+     */
+    protected $rotation;
+
+    /**
+     * Center point 
+     * 
+     * @var ezcGraphCoordinate
+     */
+    protected $center;
+
+    /**
+     * Construct rotation matrix from rotation (in degrees) and optional 
+     * center point.
+     * 
+     * @param int $rotation 
+     * @param ezcGraphCoordinate $center 
+     * @return ezcGraphTransformation
+     */
+    public function __construct( $rotation = 0, ezcGraphCoordinate $center = null )
+    {
+        $this->rotation = (float) $rotation;
+
+        if ( $center === null )
+        {
+            $clockwiseRotation = deg2rad( $rotation );
+            $rotationMatrixArray = array( 
+                array( cos( $clockwiseRotation ), -sin( $clockwiseRotation ), 0 ),
+                array( sin( $clockwiseRotation ), cos( $clockwiseRotation ), 0 ),
+                array( 0, 0, 1 ),
+            );
+
+            return parent::__construct( $rotationMatrixArray );
+        }
+
+        parent::__construct();
+
+        $this->center = $center;
+
+        $this->multiply( new ezcGraphTranslation( $center->x, $center->y ) );
+        $this->multiply( new ezcGraphRotation( $rotation ) );
+        $this->multiply( new ezcGraphTranslation( -$center->x, -$center->y ) );
+    }
+}
+
+?>
diff --git a/src/math/transformation.php b/src/math/transformation.php
new file mode 100644
index 0000000..cddec68
--- /dev/null
+++ b/src/math/transformation.php
@@ -0,0 +1,86 @@
+<?php
+/**
+ * File containing the ezcGraphTransformation class
+ *
+ * @package Graph
+ * @version //autogentag//
+ * @copyright Copyright (C) 2005-2007 eZ systems as. All rights reserved.
+ * @license http://ez.no/licenses/new_bsd New BSD License
+ * @access private
+ */
+/**
+ * Class defining transformations like scaling and rotation by a 
+ * 3x3 transformation matrix for |R^2
+ *
+ * @package Graph
+ * @access private
+ */
+class ezcGraphTransformation extends ezcGraphMatrix
+{
+    /**
+     * Constructor
+     *
+     * Creates a matrix with 3x3 dimensions. Optionally accepts an array to 
+     * define the initial matrix values. If no array is given an identity 
+     * matrix is created.
+     * 
+     * @param int $rows
+     * @param int $columns
+     * @param array $values
+     * @return void
+     */
+    public function __construct( array $values = null )
+    {
+        parent::__construct( 3, 3, $values );
+    }
+
+    /**
+     * Multiplies two matrices
+     *
+     * Multiply current matrix with another matrix and returns the result 
+     * matrix.
+     *
+     * @param ezcGraphMatrix $matrix Second factor
+     * @returns ezcGraphMatrix Result matrix
+     */
+    public function multiply( ezcGraphMatrix $matrix ) 
+    {
+        $mColumns = $matrix->columns();
+
+        // We want to ensure, that the matrix stays 3x3
+        if ( ( $this->columns !== $matrix->rows() ) &&
+             ( $this->rows !== $mColumns ) )
+        {
+            throw new ezcGraphMatrixInvalidDimensionsException( $this->columns, $this->rows, $mColumns, $matrix->rows() );
+        }
+
+        $result = parent::multiply( $matrix );
+
+        // The matrix dimensions stay the same, so that we can modify $this.
+        for ( $i = 0; $i < $this->rows; ++$i ) 
+        {
+            for ( $j = 0; $j < $mColumns; ++$j ) 
+            {
+                $this->set( $i, $j, $result->get( $i, $j ) );
+            }
+        }
+
+        return $this;
+    }
+
+    /**
+     * Transform a coordinate with the current transformation matrix.
+     * 
+     * @param ezcGraphCoordinate $coordinate 
+     * @return ezcGraphCoordinate
+     */
+    public function transformCoordinate( ezcGraphCoordinate $coordinate )
+    {
+        $vector = new ezcGraphMatrix( 3, 1, array( array( $coordinate->x ), array( $coordinate->y ), array( 1 ) ) );
+        $vector = parent::multiply( $vector );
+
+        return new ezcGraphCoordinate( $vector->get( 0, 0 ), $vector->get( 1, 0 ) );
+    }
+}
+
+?>
diff --git a/src/math/translation.php b/src/math/translation.php
new file mode 100644
index 0000000..04fe642
--- /dev/null
+++ b/src/math/translation.php
@@ -0,0 +1,29 @@
+<?php
+/**
+ * File containing the ezcGraphTranslation class
+ *
+ * @package Graph
+ * @version //autogentag//
+ * @copyright Copyright (C) 2005-2007 eZ systems as. All rights reserved.
+ * @license http://ez.no/licenses/new_bsd New BSD License
+ * @access private
+ */
+/**
+ * Class creating translation matrices from given movements
+ *
+ * @package Graph
+ * @access private
+ */
+class ezcGraphTranslation extends ezcGraphTransformation
+{
+    public function __construct( $x = 0, $y = 0 )
+    {
+        parent::__construct( array( 
+            array( 1, 0, $x ),
+            array( 0, 1, $y ),
+            array( 0, 0, 1 ),
+        ) );
+    }
+}
+
+?>
diff --git a/src/math/vector.php b/src/math/vector.php
index c8ff3bc..6397c31 100644
--- a/src/math/vector.php
+++ b/src/math/vector.php
@@ -165,6 +165,22 @@ class ezcGraphVector extends ezcGraphCoordinate
     {
         return new ezcGraphVector( $coordinate->x, $coordinate->y );
     }
+
+    /**
+     * Transform vector using transformation matrix
+     * 
+     * @param ezcGraphTransformation $transformation 
+     * @return ezcGraphVector
+     */
+    public function transform( ezcGraphTransformation $transformation )
+    {
+        $result = $transformation->transformCoordinate( $this );
+
+        $this->x = $result->x;
+        $this->y = $result->y;
+
+        return $this;
+    }
 }
 
 ?>