note 57226 added to function.imagerotate

The following is potentially useful. It extracts the central largest circle of an image into a square of specified size, and optionally rotates it. The rest of the square is made transparent, so useful for drawing over other images. I've named it after binocular effect because on some old TV shows whenever they show someone looking through binoculars the screen shows a big circular image with black edges. <?php function image_binocular_effect($src, $bearing, $out_square) { // the source image is resampled to fit within the specified square, and rotated clockwise by bearing. // the largest circle within the image is retained, the rest made transparent. $out = imagecreatetruecolor($out_square, $out_square); $width=imagesx($src); $height=imagesy($src); $square=min($width, $height); imagecopyresampled($out, $src, 0, 0, ($width - $square)/2 , ($height - $square)/2, $out_square, $out_square, $square, $square); $mask = imagecreatetruecolor($out_square, $out_square); $black = ImageColorAllocate ($mask, 0, 0, 0); $white = ImageColorAllocate ($mask, 255, 255, 255); imagefilledrectangle($mask , 0, 0, $out_square, $out_square, $white); $centrexy=$out_square / 2; imagefilledellipse($mask, $centrexy, $centrexy, $out_square, $out_square, $black); ImageColorTransparent($mask, $black); imagecopymerge($out, $mask, 0, 0, 0, 0, $out_square, $out_square, 100); if ($bearing != 0) { $rotated_img=imagerotate($out , 360-$bearing, $white); // take off only the rotated width $rotated_map_width = imagesx($rotated_img); $rotated_map_height = imagesy($rotated_img); imagecopy($out, $rotated_img, 0, 0, ($rotated_map_width - $out_square) / 2, ($rotated_map_height - $out_square) / 2, $out_square, $out_square); } ImageColorTransparent($out, $white); return $out; } // Create a sample image to demonstrate the effect, but looks much better on real photos. $src = imagecreatetruecolor(200, 50); imagefilledrectangle($src, 0, 0, 200, 50, imagecolorallocate($src, 255, 255, 255)); ImageString($src, 3, 10, 10, "This is a sample image to illustrate the binocular effect", imagecolorallocate($im, 192, 0, 0)); $img=image_binocular_effect($src, 72, 50); ImagePNG($img,"test.png"); ?> ---- Manual Page -- http://www.php.net/manual/en/function.imagerotate.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+57226 Delete: added to the manual -- http://master.php.net/manage/user-notes.php?action=delete+57226&report=yes&reason=added+to+the+manual Delete: bad code -- http://master.php.net/manage/user-notes.php?action=delete+57226&report=yes&reason=bad+code Delete: spam -- http://master.php.net/manage/user-notes.php?action=delete+57226&report=yes&reason=spam Delete: useless -- http://master.php.net/manage/user-notes.php?action=delete+57226&report=yes&reason=useless Delete: non-english -- http://master.php.net/manage/user-notes.php?action=delete+57226&report=yes&reason=non-english Delete: already in docs -- http://master.php.net/manage/user-notes.php?action=delete+57226&report=yes&reason=already+in+docs Delete: other reasons -- http://master.php.net/manage/user-notes.php?action=delete+57226&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+57226&report=yes Search -- http://master.php.net/manage/user-notes.php