Add option for small images gthomas2#46

filter.php

@@ -200,7 +200,13 @@ private function process_img_tag(array $match) {
 
         $imageinfo = (object) $file->get_imageinfo();
         if ($imageinfo->width <= $maxwidth && !local::file_is_public($file->get_contenthash())) {
-            return $match[0];
+            if (empty($this->config->lovsmallimage) || $this->config->loadonvisible == 999) {
+                return $match[0];
+            } else {
+                // Apply load on visible.
+                $url = new \moodle_url($CFG->wwwroot . '/' . $match[3]);
+                return $this->apply_loadonvisible($match, $file, $url, $url);
+            }
         }
 
         $optimisedpath = local::get_optimised_path($file, $match[3]);

lang/en/filter_imageopt.php

@@ -29,6 +29,8 @@
 $string['donotloadonvisible'] = 'No placeholding, load immediately';
 $string['loadonvisibilityall'] = 'All images';
 $string['loadonvisibilityafter'] = 'After {$a} image(s)';
+$string['lovsmallimage'] = 'Load when visible for small images';
+$string['lovsmallimagedesc'] = 'Apply "Load when visible" for images which are smaller than "Maximum image width"';
 $string['widthattribute'] = 'Image width attribute';
 $string['widthattributedesc'] = 'How should existing image width attributes be dealt with';
 $string['widthattpreserve'] = 'Preserve user width attributes in all cases';

settings.php

@@ -48,6 +48,13 @@
     $settings->add(new admin_setting_configselect('filter_imageopt/loadonvisible', get_string('loadonvisible', 'filter_imageopt'),
         get_string('loadonvisibledesc', 'filter_imageopt'), 5, $choices));
 
+    $settings->add(new admin_setting_configcheckbox(
+        'filter_imageopt/lovsmallimage',
+        get_string('lovsmallimage', 'filter_imageopt'),
+        get_string('lovsmallimagedesc', 'filter_imageopt'),
+        0
+    ));
+
     $choices = [
         local::WIDTH_ATT_PRESERVE_MAX => get_string('widthattpreserveltmax', 'filter_imageopt'),
         local::WIDTH_ATT_PRESERVE => get_string('widthattpreserve', 'filter_imageopt')