function watermark::create_watermark in ImageCache Actions 7

Same name and namespace in other branches

1. 8 watermark.inc \watermark::create_watermark()
2. 5.3 watermark.inc \watermark::create_watermark()
3. 5.2 watermark.inc \watermark::create_watermark()
4. 6.2 watermark.inc \watermark::create_watermark()
5. 6 watermark.inc \watermark::create_watermark()

TODO

Parameters

resource $main_img_obj:

resource $watermark_img_obj:

int $x_ins:

int $y_ins:

int $alpha_level:

Return value

resource

File

./watermark.inc, line 27

Routine for image layering.

Class

watermark

@file Routine for image layering.

Code

function create_watermark($main_img_obj, $watermark_img_obj, $x_ins, $y_ins, $alpha_level = 100) {
  $alpha_level /= 100;

  // Should this change to match both images?

  //$main_img_obj_w = max(imagesx($main_img_obj), imagesx($watermark_img_obj));

  //$main_img_obj_h = max(imagesy($main_img_obj), imagesy($watermark_img_obj));
  $main_img_obj_w = imagesx($main_img_obj);
  $main_img_obj_h = imagesy($main_img_obj);
  $watermark_img_obj_w = imagesx($watermark_img_obj);
  $watermark_img_obj_h = imagesy($watermark_img_obj);
  $main_img_obj_min_x = $x_ins;
  $main_img_obj_min_y = $y_ins;
  $return_img = imagecreatetruecolor($main_img_obj_w, $main_img_obj_h);
  imagesavealpha($return_img, TRUE);
  imagealphablending($return_img, FALSE);
  for ($y = 0; $y < $main_img_obj_h; $y++) {
    for ($x = 0; $x < $main_img_obj_w; $x++) {
      $return_color = NULL;
      $watermark_x = $x - $main_img_obj_min_x;
      $watermark_y = $y - $main_img_obj_min_y;
      $main_rgb = imagecolorsforindex($main_img_obj, imagecolorat($main_img_obj, $x, $y));
      if ($watermark_x >= 0 && $watermark_x < $watermark_img_obj_w && $watermark_y >= 0 && $watermark_y < $watermark_img_obj_h) {
        $watermark_rbg = imagecolorsforindex($watermark_img_obj, imagecolorat($watermark_img_obj, $watermark_x, $watermark_y));
        $watermark_alpha = round((127 - $watermark_rbg['alpha']) / 127, 2);
        $watermark_alpha = $watermark_alpha * $alpha_level;
        $avg_red = $this
          ->_get_ave_color($main_rgb['red'], $watermark_rbg['red'], $watermark_alpha);
        $avg_green = $this
          ->_get_ave_color($main_rgb['green'], $watermark_rbg['green'], $watermark_alpha);
        $avg_blue = $this
          ->_get_ave_color($main_rgb['blue'], $watermark_rbg['blue'], $watermark_alpha);

        // TODO figure out the maths for merging two transparent images.
        $new_alpha = min($watermark_rbg['alpha'], $main_rgb['alpha']);

        //$new_alpha = $main_rgb['alpha'];

        //$new_alpha = 0;
        $return_color = $this
          ->_get_image_color($return_img, $avg_red, $avg_green, $avg_blue, $new_alpha);
      }
      else {
        $return_color = imagecolorat($main_img_obj, $x, $y);
      }
      imagesetpixel($return_img, $x, $y, $return_color);
    }
  }
  return $return_img;
}