What’s a Reference Image?

A reference image is just an image file that is imported directly into Studio as a plane in the 3D scene. Reference images are a common tool in 3D design programs. In Studio, you can use reference images to help align proportions and details. They can also help avoid having to switch back and forth between Studio and an image viewer.

Adding a Reference Image

Reference images can be added via the Model > Add Reference Image menu item. This opens a file browser to choose the desired image. You can choose any PNG or JPG image file from your computer as a reference image.

adding

Once a reference image is added, it will follow the mouse cursor until you click to place it. The next section covers how to further alter the location, rotation, and size of the image.

Arranging Reference Images

Once a reference image is added, you will likely want to position it to align with the location, rotation, and size that you want to build your model. You can of course go back and modify this at any point while building.

Moving

You can move a reference image either by dragging it or by using the move tool from the action palette. Just like moving bricks, select the reference image (or images) you wish to move, hover over the wrench icon, and then click the translate icon to show the tool. You can also move both bricks and reference images at the same time.

Rotating

Similarly to translating, you can rotate reference images using the same tools as bricks. The rotate shortcuts (default: arrow keys) provide a quick way to rotate on the Y axis in 90 degree increments, while the action palette rotation tool allows you to make precise rotations on any axis. Unlike translation, currently, using the rotation tool for both bricks and reference images at the same time does not work (however the rotate shortcuts do).

Resizing

In addition to rotating and scaling, reference images have another manipulation tool not present for bricks: the scale/resize tool. This tool is accessed via the action palette just like the translation and rotation tools, but is only available when your selection is a single reference image. The scale tool shows eight handles: one at every corner of the image and one at each edge midpoint. Dragging thesehandles allows you to resize the image, like resizing an image in any graphic design application. Dragging these handles always maintains the image’s width/height ratio.

You can also resize reference images using the controls in the bottom bar. These controls are only visible when a single reference image is selected, and allow you to enter a precise width and height for the image, in addition to specifying what units these measurements are in. Unlike the scale tool, the bottom bar gives you the option to independently control the width and height – you can do so by clicking once on the link icon next to the size controls.

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Working with Reference Images

Once a reference image is positioned correctly, there are several additional tools to help you get the most benefit from the feature while building.

Brick Dragging

When placing bricks or dragging existing bricks, they will align with the reference image if you hover over it. This allows you to place bricks right up against the image, just like you can with the ground. Bricks placed against a reference image will be snapped to your current grid size.

Locking

Once a reference image is placed, you will likely not want to modify it frequently. Having a large object in the scene can easily lead to accidentally selecting and/or dragging it unintentionally. To avoid this, you can use the locking feature, which temporarily disables a reference image from being selected or dragged.

There are several ways to lock a reference image:

Clicking the lock button in the action palette.

Clicking “lock to pin” in the bottom bar.

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Right-clicking on a reference image in the viewport and clicking “lock” in the context menu.

Clicking the lock icon next to the reference image’s entry in the step list.

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When a reference image is locked, you can still select it by clicking on its entry in the step list or right-clicking on it in the viewport. These methods enable you to later unlock the image if desired.

Hiding

You may also wish to hide a reference image completely.

This works the same as hiding bricks, and can be done in the following ways:

Right-clicking on a reference image in the viewport and clicking “hide” in the context menu.

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Clicking the eye icon next to the reference image’s entry in the step list.

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Using the hide tool or hide shortcut.

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Opacity

To make a reference image more or less visible, you can change its opacity in the bottom bar. An opacity of 100% means fully opaque, and 0% means fully invisible. Note that setting opacity to 0% is not the same as hiding, as the reference image will still be selectable and used to place bricks against.

If the reference image is a PNG file with transparency, the transparency may not show up correctly at 100% opacity. Setting it to 99% will resolve this issue.

You may encounter rendering issues with reference images at near-full opacity due to limitations in how transparent surfaces can be rendered. To resolve these issues, either lower the opacity to make them less noticeable or raise it to 100%.

Overlay

Once you’ve placed many bricks, it may no longer be possible to see your reference image, as there are bricks in front of it. In order to keep the image visible, you can use the overlay feature. This enables you to see the reference image through even completely opaque bricks.