|
|
|
|
Bookmark this on Delicious
Share on Facebook
 Slashdot It!
Digg  imageftbbox
Give the bounding box of a text using fonts via freetype2
(PHP 4 >= 4.0.7, PHP 5)
Code Examples / Notes » imageftbboxphpimageftbbox
This function can be used to generate right-aligned text. Just work out how wide the text image is and position it accordingly. Example: $i_width = 200; $i_height = 40; $string = "Hello World!"; $pointsize = 10; $fontfile = "/usr/local/lib/ttf/Helve.ttf"; $im = imagecreate($i_width, $i_height); $black = imagecolorallocate ($im, 0, 0, 0); $white = imagecolorallocate ($im, 255, 255, 255); $string_size = ImageFtBbox($pointsize, 0, $fontfile, $string, array("linespacing" => 1)); $s_width = $string_size[4]; $s_height = $string_size[5]; ImageFtText($im, $pointsize, 0, $i_width - $s_width - 1, 0 - $s_height, $white, $fontfile, $string, array("linespacing" => 1)); Header ("Content-type: image/png"); ImagePNG ($im); ImageDestroy ($im); fernando
imagettfbbox() returns an array with 8 elements representing four points making the bounding box of the text: 0 lower left corner, X position 1 lower left corner, Y position 2 lower right corner, X position 3 lower right corner, Y position 4 upper right corner, X position 5 upper right corner, Y position 6 upper left corner, X position 7 upper left corner, Y position The points are relative to the text regardless of the angle, so "upper left" means in the top left-hand corner seeing the text horizontally. groomed
ImageFTBBox returns a bounding box, not metrics, as some (most?) of the notes above seem to assume. The 8 values it returns specify the 4 corners of this bounding box. So to properly determine the width and height of a string you need to do: $bbox = ImageFTBBox(...); $width = abs($bbox[0]) + abs($bbox[2]); // distance from left to right $height = abs($bbox[1]) + abs($bbox[5]); // distance from top to bottom theo v e
IF we accept the idea that a bouding box is returned then: $bbox= imageftbbox ( $size, $angle, $font, $txt); $width = abs($bbox[4] - $bbox[0]); $height = abs($bbox[1] - $bbox[5]); may be a better kind of math. But it depends... You may want to subtract yet another '1' from both the width and the height. But try drawing a "p" and next try a "d". Their bounding boxes differ 1 px in height. Of course the respective boxes, by imagefttext(), are placed at a different y coordinate. I noticed that if a "p" or a "b" is drawn at (0, 30) the first character of the string actually starts on, fills, the third horizontal pixel. Also: if your image is only 30 pixels in heigth, drawing text at (0, 30) means that the bottoms parts of "p", "q", "y" and alike are somewhere else... ta
i've found a work around for this situation it seems that height is directly proportional to line spacing so you just have to apply the same factor to image height for example : $spacing = 0.7; $params = array("linespacing" => $spacing); $box = imageftbbox ($size, 0, $font, $text, $params); $tw=$box[4]-$box[0]; //image width $th=($box[1]-$box[5])*$spacing; //image height brian
I noticed that PHP's True Type functions do not allow you to create text blocks with multiple lines that automatically adjust for alignment. I wrote a function that will allow you to generate images with multiple lines, control the alignment, and handle rotation. I hope it helps someone. There was too much code to paste on this message post so you can grab it off of my webserver. I also created an example page so that you can see the code in action. Example Page: http://www.PrintsMadeEasy.com/code_samples/php/text_generation.php Download the Text file: http://www.PrintsMadeEasy.com /code_samples/php/text_generation.txt sectionthirty1
Here is a handy example I used to center "dynamic text" onto an image. Ex. Say you want to center a clients IP Address onto a picture. $ip=$_SERVER['REMOTE_ADDR']; $details = imageftbbox($fontsize, 0, $font, $ip, array("linespacing" => 1)); $xcoord = ($imgwidth - $details[4]) / 2; // this will return the x coordinate centered to your specific image. Make sure you set $imgwidth to the width of the image you are using. imagettftext($image, $fontsize, 0, $xcoord, $ycoord, $fontcolor, $font, $ip); theo v e -2
ah... the problem between imageftbbox() and imagefttext() lies in the mirroring of the y-axes. Below you see, for a font-size 16 the boudingboxes of "b", "p" and "bp": < b: w=9 h=15 b(0,-1) b(9,-1) b(9,-16) b(0,-16) < p: w=9 h=16 p(0,4) p(9,4) p(9,-12) p(0,-12) < bp: w=20 h=20 bp(0,4) bp(20,4) bp(20,-16) bp(0,-16) If drawing "bp" using imagefttext() at y=0, the the top of "bp" indeed is at y=-16, and the bottom of "bp" at y=4. (Plus or minus a pixel here and there, because at y=0 there actually is a vissible pixel.) |
Change Language
gd_info getimagesize image_type_to_extension image_type_to_mime_type image2wbmp imagealphablending imageantialias imagearc imagechar imagecharup imagecolorallocate imagecolorallocatealpha imagecolorat imagecolorclosest imagecolorclosestalpha imagecolorclosesthwb imagecolordeallocate imagecolorexact imagecolorexactalpha imagecolormatch imagecolorresolve imagecolorresolvealpha imagecolorset imagecolorsforindex imagecolorstotal imagecolortransparent imageconvolution imagecopy imagecopymerge imagecopymergegray imagecopyresampled imagecopyresized imagecreate imagecreatefromgd2 imagecreatefromgd2part imagecreatefromgd imagecreatefromgif imagecreatefromjpeg imagecreatefrompng imagecreatefromstring imagecreatefromwbmp imagecreatefromxbm imagecreatefromxpm imagecreatetruecolor imagedashedline imagedestroy imageellipse imagefill imagefilledarc imagefilledellipse imagefilledpolygon imagefilledrectangle imagefilltoborder imagefilter imagefontheight imagefontwidth imageftbbox imagefttext imagegammacorrect imagegd2 imagegd imagegif imagegrabscreen imagegrabwindow imageinterlace imageistruecolor imagejpeg imagelayereffect imageline imageloadfont imagepalettecopy imagepng imagepolygon imagepsbbox imagepsencodefont imagepsextendfont imagepsfreefont imagepsloadfont imagepsslantfont imagepstext imagerectangle imagerotate imagesavealpha imagesetbrush imagesetpixel imagesetstyle imagesetthickness imagesettile imagestring imagestringup imagesx imagesy imagetruecolortopalette imagettfbbox imagettftext imagetypes imagewbmp imagexbm iptcembed iptcparse jpeg2wbmp png2wbmp |
