source: sourcecode/application/libraries/PHPExcel/Shared/Drawing.php @ 1

<?php
/**
 * PHPExcel
 *
 * Copyright (c) 2006 - 2014 PHPExcel
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * @category   PHPExcel
 * @package    PHPExcel_Shared
 * @copyright  Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)
 * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
 * @version    1.8.0, 2014-03-02
 */


/**
 * PHPExcel_Shared_Drawing
 *
 * @category   PHPExcel
 * @package    PHPExcel_Shared
 * @copyright  Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)
 */
class PHPExcel_Shared_Drawing
{
        /**
         * Convert pixels to EMU
         *
         * @param       int $pValue     Value in pixels
         * @return      int                     Value in EMU
         */
        public static function pixelsToEMU($pValue = 0) {
                return round($pValue * 9525);
        }

        /**
         * Convert EMU to pixels
         *
         * @param       int $pValue     Value in EMU
         * @return      int                     Value in pixels
         */
        public static function EMUToPixels($pValue = 0) {
                if ($pValue != 0) {
                        return round($pValue / 9525);
                } else {
                        return 0;
                }
        }

        /**
         * Convert pixels to column width. Exact algorithm not known.
         * By inspection of a real Excel file using Calibri 11, one finds 1000px ~ 142.85546875
         * This gives a conversion factor of 7. Also, we assume that pixels and font size are proportional.
         *
         * @param       int $pValue     Value in pixels
         * @param       PHPExcel_Style_Font $pDefaultFont       Default font of the workbook
         * @return      int                     Value in cell dimension
         */
        public static function pixelsToCellDimension($pValue = 0, PHPExcel_Style_Font $pDefaultFont) {
                // Font name and size
                $name = $pDefaultFont->getName();
                $size = $pDefaultFont->getSize();

                if (isset(PHPExcel_Shared_Font::$defaultColumnWidths[$name][$size])) {
                        // Exact width can be determined
                        $colWidth = $pValue
                                * PHPExcel_Shared_Font::$defaultColumnWidths[$name][$size]['width']
                                / PHPExcel_Shared_Font::$defaultColumnWidths[$name][$size]['px'];
                } else {
                        // We don't have data for this particular font and size, use approximation by
                        // extrapolating from Calibri 11
                        $colWidth = $pValue * 11
                                * PHPExcel_Shared_Font::$defaultColumnWidths['Calibri'][11]['width']
                                / PHPExcel_Shared_Font::$defaultColumnWidths['Calibri'][11]['px'] / $size;
                }

                return $colWidth;
        }

        /**
         * Convert column width from (intrinsic) Excel units to pixels
         *
         * @param       float   $pValue         Value in cell dimension
         * @param       PHPExcel_Style_Font $pDefaultFont       Default font of the workbook
         * @return      int             Value in pixels
         */
        public static function cellDimensionToPixels($pValue = 0, PHPExcel_Style_Font $pDefaultFont) {
                // Font name and size
                $name = $pDefaultFont->getName();
                $size = $pDefaultFont->getSize();

                if (isset(PHPExcel_Shared_Font::$defaultColumnWidths[$name][$size])) {
                        // Exact width can be determined
                        $colWidth = $pValue
                                * PHPExcel_Shared_Font::$defaultColumnWidths[$name][$size]['px']
                                / PHPExcel_Shared_Font::$defaultColumnWidths[$name][$size]['width'];

                } else {
                        // We don't have data for this particular font and size, use approximation by
                        // extrapolating from Calibri 11
                        $colWidth = $pValue * $size
                                * PHPExcel_Shared_Font::$defaultColumnWidths['Calibri'][11]['px']
                                / PHPExcel_Shared_Font::$defaultColumnWidths['Calibri'][11]['width'] / 11;
                }

                // Round pixels to closest integer
                $colWidth = (int) round($colWidth);

                return $colWidth;
        }

        /**
         * Convert pixels to points
         *
         * @param       int $pValue     Value in pixels
         * @return      int                     Value in points
         */
        public static function pixelsToPoints($pValue = 0) {
                return $pValue * 0.67777777;
        }

        /**
         * Convert points to pixels
         *
         * @param       int $pValue     Value in points
         * @return      int                     Value in pixels
         */
        public static function pointsToPixels($pValue = 0) {
                if ($pValue != 0) {
                        return (int) ceil($pValue * 1.333333333);
                } else {
                        return 0;
                }
        }

        /**
         * Convert degrees to angle
         *
         * @param       int $pValue     Degrees
         * @return      int                     Angle
         */
        public static function degreesToAngle($pValue = 0) {
                return (int)round($pValue * 60000);
        }

        /**
         * Convert angle to degrees
         *
         * @param       int $pValue     Angle
         * @return      int                     Degrees
         */
        public static function angleToDegrees($pValue = 0) {
                if ($pValue != 0) {
                        return round($pValue / 60000);
                } else {
                        return 0;
                }
        }

        /**
         * Create a new image from file. By alexander at alexauto dot nl
         *
         * @link http://www.php.net/manual/en/function.imagecreatefromwbmp.php#86214
         * @param string $filename Path to Windows DIB (BMP) image
         * @return resource
         */
        public static function imagecreatefrombmp($p_sFile)
        {
        //    Load the image into a string
        $file    =    fopen($p_sFile,"rb");
        $read    =    fread($file,10);
        while(!feof($file)&&($read<>""))
            $read    .=    fread($file,1024);

        $temp    =    unpack("H*",$read);
        $hex    =    $temp[1];
        $header    =    substr($hex,0,108);

        //    Process the header
        //    Structure: http://www.fastgraph.com/help/bmp_header_format.html
        if (substr($header,0,4)=="424d")
        {
            //    Cut it in parts of 2 bytes
            $header_parts    =    str_split($header,2);

            //    Get the width        4 bytes
            $width            =    hexdec($header_parts[19].$header_parts[18]);

            //    Get the height        4 bytes
            $height            =    hexdec($header_parts[23].$header_parts[22]);

            //    Unset the header params
            unset($header_parts);
        }

        //    Define starting X and Y
        $x                =    0;
        $y                =    1;

        //    Create newimage
        $image            =    imagecreatetruecolor($width,$height);

        //    Grab the body from the image
        $body            =    substr($hex,108);

        //    Calculate if padding at the end-line is needed
        //    Divided by two to keep overview.
        //    1 byte = 2 HEX-chars
        $body_size        =    (strlen($body)/2);
        $header_size    =    ($width*$height);

        //    Use end-line padding? Only when needed
        $usePadding        =    ($body_size>($header_size*3)+4);

        //    Using a for-loop with index-calculation instaid of str_split to avoid large memory consumption
        //    Calculate the next DWORD-position in the body
        for ($i=0;$i<$body_size;$i+=3)
        {
            //    Calculate line-ending and padding
            if ($x>=$width)
            {
                //    If padding needed, ignore image-padding
                //    Shift i to the ending of the current 32-bit-block
                if ($usePadding)
                    $i    +=    $width%4;

                //    Reset horizontal position
                $x    =    0;

                //    Raise the height-position (bottom-up)
                $y++;

                //    Reached the image-height? Break the for-loop
                if ($y>$height)
                    break;
            }

            //    Calculation of the RGB-pixel (defined as BGR in image-data)
            //    Define $i_pos as absolute position in the body
            $i_pos    =    $i*2;
            $r        =    hexdec($body[$i_pos+4].$body[$i_pos+5]);
            $g        =    hexdec($body[$i_pos+2].$body[$i_pos+3]);
            $b        =    hexdec($body[$i_pos].$body[$i_pos+1]);

            //    Calculate and draw the pixel
            $color    =    imagecolorallocate($image,$r,$g,$b);
            imagesetpixel($image,$x,$height-$y,$color);

            //    Raise the horizontal position
            $x++;
        }

        //    Unset the body / free the memory
        unset($body);

        //    Return image-object
        return $image;
        }

}