Advanced Image Editing Under the GD Library Page 5

Textures

Textures are one of the hardest text effects possible. This is due to the fact that you need to know how to use a mask to create the texture.

<?php
function imagettftexttexture(&$im,&$textureim,$size,$angle,$x,$y,$fontfile,$text) {
    $width = imagesx($im); // Get the width of the image
    $height = imagesy($im); // Get the height of the image
    $buffer = imagecreate($width,$height); // Create the buffer image
    $tile_w = imagesx($textureim); // Get the width of the texture image
    $tile_h = imagesy($textureim); // Get the height of the texture image
    $fits_x = (int)($im_w/$tile_w); // Find out how many times it fits horizontally
    $fits_y = (int)($im_h/$tile_h); // Find out how many times it fits vertically
    for ($i=0;$i<=$fits_x;$i++) { // Loop through every time (and another, for extra space) it fits horizontally
        $x = (int)($tile_w*$i); // Change the X location based on where in the loop it is
        for ($i2=0;$i2<=$fits_y;$i2++) { // Loop through every time it fits vertically
            $y = (int)($tile_h*$i2); // Change the Y location
            $copy = imagecopy($im,$textureim,$x,$y,0,0,$tile_w,$tile_h); // Copy the image to the X,Y location
        }
    }
    $pink = imagecolorclosest($im,255,0,255); // Create magic pink, a color commonly used for masks
    $trans = imagecolortransparent($im,$pink); // Make magic pink the transparent color
    imagettftext($im,$size,$angle,$x,$y,-$pink,$fontfile,$text); // Draw text over magic pink without aliasing
    imagecopy($buffer,$im,0,0,0,0,$width,$height); // Copy the main image onto the buffer
    imagecopy($im,$buffer,0,0,0,0,$width,$height); // Copy the buffer back onto the main image
    imagedestroy($buffer); // Destroy the buffer
}
?>

This is the longest code section from this entire tutorial, all for a simple textured effect. You see this done in many graphic-editing programs, and now you know how it can be done through PHP and GD. Since we had to use very specific colors in order to get the mask to work, aliasing the text is nearly impossible; therefore, the image may appear more “crude,” or choppy. If we call imagettftexttexture ($img,$texture,40,0,10,50,”arial.ttf”,”AaBbCcDd”) where $texture contains a brick tile, we can create this image:

This concludes the advanced image editing tutorial. Hopefully, you can have some fun with advanced features in GD, and create some interesting image scripts. Thanks for sticking around!

Every function in this tutorial (and more) can be found here.