width = $w; $this->height = $h; $this->direction = $d; $this->startcolor = $s; $this->endcolor = $e; $this->step = intval(abs($step)); // Attempt to create a blank image in true colors, or a new palette based image if this fails if (function_exists('imagecreatetruecolor')) { $this->image = imagecreatetruecolor($this->width,$this->height); } elseif (function_exists('imagecreate')) { $this->image = imagecreate($this->width,$this->height); } else { die('Unable to create an image'); } // Fill it $this->fill($this->image,$this->direction,$this->startcolor,$this->endcolor); // Show it $this->display($this->image); // Return it return $this->image; } // Displays the image with a portable function that works with any file type // depending on your server software configuration function display ($im) { if (function_exists("imagepng")) { header("Content-type: image/png"); imagepng($im); } elseif (function_exists("imagegif")) { header("Content-type: image/gif"); imagegif($im); } elseif (function_exists("imagejpeg")) { header("Content-type: image/jpeg"); imagejpeg($im, "", 0.5); } elseif (function_exists("imagewbmp")) { header("Content-type: image/vnd.wap.wbmp"); imagewbmp($im); } else { die("Doh ! No graphical functions on this server ?"); } return true; } // The main function that draws the gradient function fill($im,$direction,$start,$end) { switch($direction) { case 'horizontal': $line_numbers = imagesx($im); $line_width = imagesy($im); list($r1,$g1,$b1) = $this->hex2rgb($start); list($r2,$g2,$b2) = $this->hex2rgb($end); break; case 'vertical': $line_numbers = imagesy($im); $line_width = imagesx($im); list($r1,$g1,$b1) = $this->hex2rgb($start); list($r2,$g2,$b2) = $this->hex2rgb($end); break; case 'ellipse': $width = imagesx($im); $height = imagesy($im); $rh=$height>$width?1:$width/$height; $rw=$width>$height?1:$height/$width; $line_numbers = min($width,$height); $center_x = $width/2; $center_y = $height/2; list($r1,$g1,$b1) = $this->hex2rgb($end); list($r2,$g2,$b2) = $this->hex2rgb($start); imagefill($im, 0, 0, imagecolorallocate( $im, $r1, $g1, $b1 )); break; case 'ellipse2': $width = imagesx($im); $height = imagesy($im); $rh=$height>$width?1:$width/$height; $rw=$width>$height?1:$height/$width; $line_numbers = sqrt(pow($width,2)+pow($height,2)); $center_x = $width/2; $center_y = $height/2; list($r1,$g1,$b1) = $this->hex2rgb($end); list($r2,$g2,$b2) = $this->hex2rgb($start); break; case 'circle': $width = imagesx($im); $height = imagesy($im); $line_numbers = sqrt(pow($width,2)+pow($height,2)); $center_x = $width/2; $center_y = $height/2; $rh = $rw = 1; list($r1,$g1,$b1) = $this->hex2rgb($end); list($r2,$g2,$b2) = $this->hex2rgb($start); break; case 'circle2': $width = imagesx($im); $height = imagesy($im); $line_numbers = min($width,$height); $center_x = $width/2; $center_y = $height/2; $rh = $rw = 1; list($r1,$g1,$b1) = $this->hex2rgb($end); list($r2,$g2,$b2) = $this->hex2rgb($start); imagefill($im, 0, 0, imagecolorallocate( $im, $r1, $g1, $b1 )); break; case 'square': case 'rectangle': $width = imagesx($im); $height = imagesy($im); $line_numbers = max($width,$height)/2; list($r1,$g1,$b1) = $this->hex2rgb($end); list($r2,$g2,$b2) = $this->hex2rgb($start); break; case 'diamond': list($r1,$g1,$b1) = $this->hex2rgb($end); list($r2,$g2,$b2) = $this->hex2rgb($start); $width = imagesx($im); $height = imagesy($im); $rh=$height>$width?1:$width/$height; $rw=$width>$height?1:$height/$width; $line_numbers = min($width,$height); break; default: } for ( $i = 0; $i < $line_numbers; $i=$i+1+$this->step ) { // old values : $old_r=$r; $old_g=$g; $old_b=$b; // new values : $r = ( $r2 - $r1 != 0 ) ? intval( $r1 + ( $r2 - $r1 ) * ( $i / $line_numbers ) ): $r1; $g = ( $g2 - $g1 != 0 ) ? intval( $g1 + ( $g2 - $g1 ) * ( $i / $line_numbers ) ): $g1; $b = ( $b2 - $b1 != 0 ) ? intval( $b1 + ( $b2 - $b1 ) * ( $i / $line_numbers ) ): $b1; // if new values are really new ones, allocate a new color, otherwise reuse previous color. // There's a "feature" in imagecolorallocate that makes this function // always returns '-1' after 255 colors have been allocated in an image that was created with // imagecreate (everything works fine with imagecreatetruecolor) if ( "$old_r,$old_g,$old_b" != "$r,$g,$b") $fill = imagecolorallocate( $im, $r, $g, $b ); switch($direction) { case 'vertical': imagefilledrectangle($im, 0, $i, $line_width, $i+$this->step, $fill); break; case 'horizontal': imagefilledrectangle( $im, $i, 0, $i+$this->step, $line_width, $fill ); break; case 'ellipse': case 'ellipse2': case 'circle': case 'circle2': imagefilledellipse ($im,$center_x, $center_y, ($line_numbers-$i)*$rh, ($line_numbers-$i)*$rw,$fill); break; case 'square': case 'rectangle': imagefilledrectangle ($im,$i*$width/$height,$i*$height/$width,$width-($i*$width/$height), $height-($i*$height/$width),$fill); break; case 'diamond': imagefilledpolygon($im, array ( $width/2, $i*$rw-0.5*$height, $i*$rh-0.5*$width, $height/2, $width/2,1.5*$height-$i*$rw, 1.5*$width-$i*$rh, $height/2 ), 4, $fill); break; default: } } } // #ff00ff -> array(255,0,255) or #f0f -> array(255,0,255) function hex2rgb($color) { $color = str_replace('#','',$color); $s = strlen($color) / 3; $rgb[]=hexdec(str_repeat(substr($color,0,$s),2/$s)); $rgb[]=hexdec(str_repeat(substr($color,$s,$s),2/$s)); $rgb[]=hexdec(str_repeat(substr($color,2*$s,$s),2/$s)); return $rgb; } } ?>