Fisheye Mapping

Fisheye mapping projects content onto screens using a fisheye projection, simulating the effect of a hemispherical lens. This mapping type is ideal for domes, curved surfaces, or any scenario where content needs to be distributed radially from a central point.

Fisheye mapping treats all assigned screens as a unified canvas, projecting a single fisheye-warped image over all surfaces. This eliminates the need for manual calculations of pixel density or screen spacing; Designer automatically handles the correct sampling and alignment, even as surfaces move or change orientation.

An example of fisheye content: With credit to Paul Bourke. Fulldome test pattern by Paul Bourke. The images may be freely used under the condition it is not modified in any way. The image may be freely distributed as long as this license statement is included.

Creating a Fisheye Mapping

1. In your track, create a new visual layer (content, generative, or effect).
2. Select the layer to open the Layer Editor.
3. Under the Default tab, click the Mapping parameter to display available mappings.
4. In the mappings manager, create a new mapping and select Fisheye as the type.
5. An editor for the new fisheye mapping will appear.
6. Assign all screens to be used and enter the intended content resolution.
7. Assign content to the layer; it will be displayed fisheye-mapped across the assigned screens in the stage and feed output.
8. Adjust the specific fisheye mapping properties as needed.

When the Fisheye mapping editor opens, Designer highlights areas outside the mapped region and provides controls for projection parameters and cropping.

Mapping Properties

Filtering

• Nearest: Nearest neighbour filtering. Use nearest-neighbour sampling, to disable blending between pixels when scaling. Can be used to create pixellated looks, or to ensure hard edges on certain types of content.

• Bilinear: Bilinear filtering is a texture filtering method used to smooth textures when displayed larger or smaller than they actually are.

• 2x Multi-sample: Multi-Sample filtering can help fix issues with scaled content, but can introduce some blurriness.

Resolution

This controls the canvas size the layer renders into, in pixels. The Direct mapping type starts with a 256x256 pixel canvas and automatically sets the canvas size to that of the first screen you add.

Screens

This is a list of screens that the selected mapping type can copy content to.

1. Left-click + to open the Screens manager.
2. Left-click + to add the Screens you want to map. This will copy the individual canvas content onto these three Screens simultaneously and will add the Screen names to the mapping object editor.
3. Left-click and drag the Screens listed in the mapping object editor to -. This will remove the canvas content from the Screens and delete the Screen names from the mapping object editor.

Mask

This points to the Texture file that defines a Mask bitmap. You can use this property to apply a Mask bitmap to the mapping canvas. Selecting this property will open the Texture object library, which shows all of the still image files saved on your local hard-drive in the DxTexture folder.

To apply a mapping mask you will need to create and import a custom still image file.

• The step-by-step instructions on how to create and import a custom Population mask can be used to create a custom mapping mask. The only difference is that the mapping masks resolution should be the same as the mapping canvas. For step-by-step instructions on how to create and import a Population mask into a d3 project visit to the section Population mask in the Editing screens sub-chapter.

• Alternatively, set any layers blend mode to mask to channel the layer content into the mapping mask.

Offset

Sets the position of the fisheye projection’s anchor point in stage space (meters). This is relative to any parent object if the mapping is in a hierarchy.

Heading

Rotates the fisheye projection horizontally (degrees).

Elevation

Tilts the projection vertically (degrees).

Rotation

Rotates the content within the fisheye projection (degrees).

Tracking source

Attach the mapping to a tracked object.

Clip outside region

Clips pixels outside of rendered region, preserving existing colour. If not set, pixels outside the rendered region are set to the border colour.

Field of view & cropping calculator

Sets the angular extent of the fisheye projection (degrees). Increasing the FOV captures a larger area, and can extend to 360° for full spherical content. Decreasing the FOV focuses the mapping on a smaller area, and can be used to reduce file sizes. The default value is 180°.

The cropping calculator helps tune the FOV and its relationship with the mapping resolution. It provides live control over the FOV and calculates the resulting resolution as a factor of the original mapping resolution. This helps ensure that the content is sampled correctly for the intended display area.

Note that the fisheye type (below) also affects the resolution calculation, as different projection algorithms have varying sampling behaviour at different FOVs.

Fisheye type

Select the fisheye projection algorithm. Each type has different characteristics in terms of resolution distribution.

• Equidistant: Maps angles linearly to radius, providing a balanced distribution of resolution across the FOV. This is a common choice for general fisheye applications.
• Equisolid: Preserves area relationships, making it suitable for applications where equal-area representation is important, such as in planetarium projections.
• Orthographic: Projects points onto a plane, resulting in a more compressed image towards the edges. This can be useful for artistic effects or specific display requirements.
• Stereographic: Preserves angles, resulting in a larger apparent size of objects near the edge of the FOV.

Content outside circle

When disabled, content outside the circular fisheye area is clipped. When enabled, the entire rectangular mapping area is used. This can be useful if only small parts of the screen are outside of a given FOV, as the usually wasted area can be filled with content.

Content mode

Choose between 2D or 3D content mapping. In 3D mode, the lens is converted to a camera and sent to the 3D engine, allowing for true 3D perspective and parallax effects. In 2D mode, the content is always treated as a flat image, with no camera information.

Border Expansion

UV islands on screens are expanded by this many pixels to cover edge sampling artifacts such as black fringing. Note that there must be an equivalent amount of empty space in the screen UV map to take advantage of this.

Find/Replace Usages

Finds all usages of the current mapping in the project, and allows these to be replaced with an alternative mapping. Note that replacement only works for sequenced, non-sockpuppeted mappings.

Hierarchy

The hierarchy section allows the mapping to be set as a parent or child of another object, like any other object. See Object Overview for details.