sigplus has its own stylish pop-up window implementation called boxplus but also ships with several third-party animated lightbox engines. The following examples demonstrate the pop-up window types available within sigplus.

The boxplus pop-up window

sigplus has an own pop-up window implementation integrated into the extension. boxplus is bundled with the sigplus distribution, you can choose among a set of different themes: e.g. light theme and dark theme. boxplus features a scrollable thumbnail strip that helps fast navigation without closing the pop-up window. The strip can be positioned either above or below the image being shown, or aligned to the top or bottom of the image.

{gallery lightbox="boxplus/dark" lightbox:navigation="below"}budapest{/gallery}
{gallery lightbox="boxplus/light" lightbox:navigation="bottom"}budapest{/gallery}

boxplus comes with a lot of parameters, not all of which are exposed on the sigplus plug-in and module configuration pages. However, you can pass parameters directly to lightbox, rotator and caption engines by adding a prefix to an engine-specific parameter. For example, you can use the following syntax to make the boxplus lightbox engine position the quick-access navigation bar at the bottom of the image view area, and place the caption above and the controls (such as Previous and Next buttons) below the main image:

{gallery lightbox:navigation=bottom lightbox:captions=above lightbox:controls=below}budapest{/gallery}

In the example above, controls is the name of a parameter boxplus understands, and lightbox: (ending with a colon) tells sigplus to forward it to boxplus without changes. For a full list of parameters, check out how to set custom gallery parameters on the boxplus project page.

Desktop vs. mobile screen

boxplus utilizes a device feature called device pixel ratio; if the device you are using (e.g. a mobile phone or a MacBook) consumes multiple (logical) image pixels to show a (physical) screen pixel, then boxplus will respect this and behave accordingly. This means that the image might appear smaller when shown on a mobile/tablet than the same image shown on a desktop, at least relative to other screen content. You can suppress device pixel ratio with configuration settings (at the expense of possibly making the image slightly pixelated). Type the following into the text field Additional settings on the Advanced tab of the sigplus plugin configuration page:


This will make boxplus ignore the physical to logical pixel ratio of the display device (e.g. mobile displays or retina display on the Mac) and force logical pixels across all devices, and therefore avoid any reduction in width/height. Desktop devices usually have a device pixel ratio of 1 (each image pixel corresponds to one pixel on the screen) whereas mobile devices usually have a ratio of 2 (a 2x2 square of image pixels corresponds to a device screen pixel). This means that an image might appear with half the width and height when shown on a mobile screen as compared to a desktop screen. Some devices might have a fractional device pixel ratio.

Third-party pop-up window engines

Click each image in the list below to see what the corresponding lightbox pop-up window engine looks like. Use the small buttons below each preview image or the pop-up window's own controls to navigate between images.

Like with boxplus, it is possible to pass engine-specific parameters directly to these other pop-up window engines with the help of the prefix lightbox: (ending with a colon). Consult the documentation of these third-party products on what parameters they accept.


Bootstrap Modal is Bootstrap's JavaScript modal plugin bundled with Joomla for displaying lightbox pop-up dialogs.

{gallery lightbox="bootstrap"}budapest{/gallery}


FancyBox is a third-party engine licensed under MIT and GPL licenses.

{gallery lightbox="fancybox"}budapest{/gallery}


hoverplus is a window engine that activates on mouse-over (unlike other engines that activate on mouse click). Useful for providing a magnifier effect.

{gallery lightbox="hoverplus"}hungary{/gallery}


Slimbox2 is a third-party engine licensed under the MIT license.

{gallery lightbox="slimbox2"}budapest{/gallery}