10. Content Mapping

Explore how to map content onto screens and lights using the many different mapping types in d3.

10.1 Content mapping overview

What is mapping?

Mapping is the process of copying content from the Timeline to the screens in the Stage level.

Conceptual diagram illustrating how mapping is used to control how content is copied from the Timeline to the Stage level

All visual layers contain the property mapping, which is used to redirect the layer output to the screen(s) in the stage. For information on how to use the mapping property please see the sub-chapter Creating a new mapping.

Types of mappings

There are six different mapping types in d3: Direct mapping, Feed mapping, Parallel mapping, Perspective mapping, Cylindrical mapping and Radial mapping.

Together these mapping types are able to: copy/spread content onto single/multiple screens; map content onto screens regardless of their sculptural form, resolution, video pixels or lighting pixels; project content onto static/moving screens; and project geometrically into the scene in a number of different ways.

For more detailed information on the mapping types please read the following sub-chapter Mapping types overview.

Rendering Stage movies

Once the content has been mapped from the Timeline onto the the screens in the Stage level it is possible to use the AnimateCamera2 layer to create a camera fly through and render this into a movie. This allows the client or entire production team to know exactly what the latest update is on the project. For more information please see the chapter Rendering Video.

10.2 Mapping types overview

Direct mapping

Direct mapping is the easiest form of mapping. Simply select a piece of content and apply it directly onto some or all of your screens. If the content aspect is different from the screen aspect ratio, you can choose to crop, fit, stretch or apply the content pixel-perfect onto the screens.

Feed mapping

Feed mapping lets you specify an arbitrary number of rectangles within your content frame and map them to arbitrary rectangles on your screens. With Feed mapping, all your screens can easily be turned into into one canvas, with pixel-perfect content applied. Individually move, scale, crop, chop or flip your sample rectangles to compensate for differences in pixel-density or to create interesting mapping effects.

Parallel mapping

Parallel mapping allows you to position your content in a virtual emitter rectangle anywhere within the stage and to choose which screens and fixtures this affects. d3 then virtually ‘projects’ the content out onto those fixtures. The content keeps the same size as it gets further away from the emitter.

Perspective mapping

Perspective mapping is similar to Parallel mapping, except that the content originates from an emitter point and gets larger as you get further away from the emitter, similar to a real projector. You can use perspective mapping to map 3D content onto a surface that looks perfect from the specified point of view.

Cylindrical mapping

Cylindrical mapping is similar to Parallel mapping, except that the Cylindrical mapping wraps content around a cylinder and fires it outwards (or inwards) at the screens you assign to it. It does not matter if the screen is moving or expanding, the Cylindrical mapping feature re-maps the content in real-time.

Radial mapping

Radial mapping is similar to the Cylindrical mapping, except that the emitter surface runs from the central axis to the cylinder rim, rather than being wrapped around the outside of the cylinder. The pixels inside the cylinder will therefore be mapped according to their height within the cylinder and their distance from the central axis.

10.3 Creating a new mapping

To create a new mapping:

Open the layer editor for the layer whose output is to be redirected. By default, the system creates a simple Direct mapping type for every screen created. The mapping type has the same name as the screen and renames itself when the screen is renamed. In the example below the output of the Bitmap layer is being mapped onto screen1, using the default mapping screen1 created by d3.

Process used to create a new mapping

Open the mappings manager by left-clicking the mapping property. This is a list of all of the different mappings.
Type in the name of the new mapping into the new mapping text field and hit Enter. A menu of the six different mapping types will open.
Left-click the appropriate mapping type and d3 will create the mapping type, add it to the Mapping key-frame editor, and open an editor for the new mapping.

For step-by-step instructions on how to use the mapping type to copy content onto the screen(s), please read the ‘Screens’ section in the following sub-chapter Common mapping type properties.

Please note: it is useful to organise the different mappings in boxes, particularly if there are a very large number of mappings. For information on how to create, edit and organise objects within boxes, please see the section ‘Organising objects in boxes’ in the Object libraries sub-chapter.

10.4 Common mapping type properties

This sub-chapter explains the properties that are shared by the six different mapping types.

Filtering

Filtering property controls how content is filtered to the output Screens

Filtering set to on applies a bilinear filter to the content being used by that specific mapping type.

Mode

There are three different mode options to choose from:

Mode property displaying options that control how content is mapped onto the output Screens

Normal

Scales the canvas to the output Screens without cropping or necessarily maintaining the aspect ratio.

Clipping

Attempts to scale and crop the canvas to the output Screens in order to maximise coverage and keep the same aspect ratio.

Pixel-perfect

Applies the content pixel-perfectly onto the mapping canvas, despite differences in resolution between the source content and the mapping canvas.

Resolution

This controls the canvas size the layer renders into, in pixels. The Direct mapping type starts with a 256×256 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.

Left-click + to open the Screens manager.

Screens manager displaying a list of Screens that the selected mapping type, in this example direct mapping 1, can copy content to

Left-click the Screens you want to map. In this example we are direct mapping screen1, screen2 and screen3. This will copy the individual canvas content onto these three Screens simultaneously and will add the Screen names to the mapping object editor.

Canvas content directly mapped onto all three Screens by adding them to the mapping object editor

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.

Canvas content removed from the three Screens by deleting them from the mapping object editor

Mask

This points to the Texture file that defines a Mask bitmap. You can use this property to multiply 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 mask’s 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 scroll down to the section ‘Population mask’ in the Editing screens sub-chapter.

Alternatively, set any layer’s blend mode to mask to channel the layer content into the mapping mask. For more information on blend modes please scroll down to the section ‘blendMode’ in the sub-chapter Common layer properties.

10.5 Direct mapping

Direct mapping is the easiest mapping type. It specifies a canvas size (in pixels) and a list of screens where the canvas content will be copied onto.

With Direct mapping you can choose to apply the same content onto one or multiple screens. For example, you can create a Direct mapping which only applies content onto Screen1 but another Direct mapping which applies the same content onto Screen1, Screen2 and Screen3.

When you create a new screen, d3 automatically creates a new Direct mapping with the same name as the screen and only includes that screen.

The resolution of the Direct mapping type is automatically set to the highest resolution screen of the screens included in the Direct mapping.

Direct mapping type used to apply the output of a Bitmap layer onto three Screens

Creating a Direct mapping

Follow the instructions in the sub-chapter Creating a new mapping and select Direct from the menu of different mapping types.

Direct mapping properties

The Direct mapping properties are all explained in the sub-chapter Common mapping type properties.

10.6 Feed mapping

The Feed mapping type allows you to sub-sample rectangular areas in a content area (referred to as the Mapping canvas) and copy those content areas onto rectangles inside one or multiple screens. For example, you can sample content from the first third of a video file onto Screen1, the second third onto Screen2 and the last part onto Screen3, pixel-perfectly or scaled.

Feed mapping is an extremely useful tool when you are aiming to create one content canvas despite having multiple screens in your stage.

In the image below, you can see a Feed mapping that samples content from different sub-rectangles and maps it onto one screen.

Feed mapping type used to sample content from different sub-rectangles onto one Screen

Creating a Feed mapping

Follow the instructions in the sub-chapter Creating a new mapping and select Feed from the menu of different mapping types.

Feed mapping properties

The Feed mapping properties are all explained in the sub-chapter Common mapping type properties.

Using the Feed mapping type

In addition to the property explanations provided in the sub-chapter Common mapping type properties, it is important to:

Set the resolution of the Feed mapping to the same resolution as the content intended to be used for that Feed mapping. If the content is of a higher resolution than the resolution of the Feed mapping mapping canvas, d3 will by default crop away the sides of the content. If the content is of lower resolution, d3 will scale up the content inside the mapping canvas.
Add the screens to the Feed mapping in the same order as they appear in the visualiser, from left to right. If the screens are not listed in that order yet, you can re-order the screens in the screens list by selecting and dragging a screen up or down.

Adding a Feed rectangle to the mapping canvas

To add a Feed rectangle to the mapping canvas:

Right-click the red screen canvas and select add feed rectangle.

View of the Feed mapping editor when adding a new Feed rectangle

Note that the Feed rectangle is by default positioned in the top left corner of the mapping canvas. To change the position of the Feed rectangle, left-click it once, place the cursor in the middle and start moving it.

View of the Feed mapping editor after all Feed rectangles have been added to the mapping canvas.

Editing a Feed rectangle in the Stage level

The Feed rectangle has a number of options for scaling, flipping and chopping the rectangle. These options are very similar to those used when editing a Feed rectangle in the Output Feeds level. For more information please see the sub-chapter Quick editing controls.

The following image explains the various options associated with a Feed rectangle in the Stage level.

Feed rectangle quick editing controls

The position of the sample rectangle placed on the Mapping Canvas, in pixels ( 1 ).
The Scissor tool on the sample rectangle for vertical cuts ( 2 ). Left-click and hold down the mouse button to move the cut horizontally.
The Scissor tool on the sample rectangle for horizontal cuts ( 3 ). Left-click and hold down the mouse button to move the cut vertically.
The Bin ( 4 ). Left-click the bin icon once to delete the sample rectangle (and the Feed rectangle).
The size of the sample rectangle in pixels ( 5 ).
The Flipping tool to flip the sample rectangle horizontally ( 6 ).
The Scissor tool on the Feed rectangle for vertical cuts ( 7 ). Left-click and hold down the mouse button to move the cut horizontally.
The Rotate tool on the Feed rectangle for rotating the Feed rectangle 90 degree clock/anti-clockwise ( 8 ).
The Scissor tool on the Feed rectangle for horizontal cuts ( 10 ). Left-click and hold down the mouse button to move the cut vertically.
The Flipping tool to flip the sample rectangle vertically( 9 ).
The Bin ( 11 ). Left-click the bin icon once to delete the Feed rectangle (and the sample rectangle).
The Lock button locks the size of the sample rectangle to the size of the Feed rectangle and vice versa ( 12 ). Left-click the Lock button once to unlock the dependency.
The name of the screen ( 13 ).
The size of the Feed rectangle in pixels ( 14 ).

Using these tools gives you a lot of freedom for configuring the Feed mapping on the screens in the Stage. Below, you can see an extreme example of this (for demonstration purposes only). Note that the red color in the background on the left hand side will only show up if the Feed mapping editor is open. When closed, the background will remain black.

Example of what the Feed mapping tools can achieve when used to map content onto the Screens

10.7 Parallel mapping

The Parallel mapping type projects content geometrically into the scene, as if ‘virtually shooting’ content from an emitting rectangle. The mapped image does not increase in size the further away you go from the emitting rectangle. Instead, the image remains the same size, hence the term ‘parallel’.

Parallel mapping is extremely powerful if you easily want to create one canvas out of multiple screens. As the content is being virtually projected onto the screens from the emitting rectangle, d3 will automatically adjust the differences in pixel-pitch among the various screens. For example, if a 30mm LED screen and a 6mm LED screen are positioned next to each other, the content will automatically appear as one seamless image across the screens.

Parallel mapping is also very useful when you want to apply content onto moving screens. As long as d3 receives the correct tracking signal, the system will automatically map the content onto the moving screens. See more about screen tracking in the sub-chapter Motion control systems.

Furthermore, Parallel mapping is a great tool for combining not only LED technology of various pixel-pitches, but also to combine LED, projection and DMX lighting into one canvas. As d3 considers all screens to be made up of pixels, regardless if they are LED, projection or DMX-based screens (including moving heads), it is very easy to combine these different type of screens into one canvas.

Please note: the Parallel mapping may not be useful when the screens are facing awkward angles in relation to the emitting rectangle of the Parallel mapping. The more they rotate away from the emitting rectangle, the more stretched the pixels will be on the screens. Ideally, the Parallel mapping should be used for straight-facing rectangular screens. For low-res sculptural screens, this is however not a problem.

Parallel mapping type used to project content onto three screens treated as a single canvas

Creating a Parallel mapping

Follow the instructions in the sub-chapter Creating a new mapping and select Parallel from the menu of different mapping types.

When the Parallel mapping editor initially opens, and assuming that the screens have been added, d3 will colour the region outside the projected image red and will give you the location and orientation details of the image source.

View of the Parallel mapping editor after configuring the resolution and setting the correct aspect

Parallel mapping properties (in addition to Common mapping type properties)

Lock

For convenience while editing, the mapping can either maintain its aspect ratio, which changes vertical size or resolution when you change horizontal size or resolution, and vice versa. The pixel density, which changes the vertical or horizontal size when you change the vertical or horizontal resolution can also be locked.

Please note: if the aspect or the density of the source content is not locked the Parallel mapping may project stretched pixels onto the screens.

Anchor

This controls the anchor point around which the mapping surface moves, scales and rotates. Select either centre to specify the position of the centre of the projection image or select corner to specify the bottom left corner of the image.

Size

This controls the size of the mapped image, in meters (horizontal and vertical).

Position

The position, in stage space (i.e. in meters) of the anchor point of the mapping source. This can be either the centre of the image or the bottom left corner of the image.

Heading

This controls the direction of the mapping in the horizontal space, in degrees: 0 degrees points ‘north’ (i.e. in the positive z axis direction). Increasing the angles will make the direction to rotate clockwise, so 90 degrees is ‘west’ (i.e. the negative x direction), 180 degrees is ‘south’ (negative z direction) and 270 degrees is ‘east’ (positive x direction).

Elevation

This controls the vertical elevation, in degrees, of the projection direction: 0 degrees is horizontal (i.e. parallel to the floor), 90 degrees is straight up and ‐90 degrees is straight down.

Rotation

This controls the rotation of the image around the mapping axis, clockwise in degrees.

Using the Parallel mapping type

In addition to the property explanations provided in the sub-chapter Common mapping type properties, it is important to:

Set the the aspect property to off and set the resolution to match the resolution of the content intended to be used for this specific Parallel mapping.
Set the size of the emitting rectangle of the Parallel mapping to match the aspect of the resolution (and thereby the aspect of the content) and then set the aspect to locked. For example, if your content is 1920×1080, set the size to 19.2 × 10.8 and then set the aspect to lock. If the aspect or the density of the source content is not locked the Parallel mapping may project stretched pixels onto the screens.
Re-size the x or y coordinates to cover all areas of the screens (the red areas will gradually disappear as you re-size the emitting rectangle).
Make sure to specify content which has the same, or a slightly higher pixel density than the screen with the highest pixel density.

10.8 Perspective mapping

Perspective mapping is similar to Parallel mapping, except that the content originates at an emitter point and gets larger in size as you go further away from the emitter, similar to a real projector. You can use Perspective mapping to make 2D content appear as 3D (not stereoscopic but rather as a 3D ‘effect’), but only from a specific point of view which is the same point as the position of the emitter.

Perspective mapping type being used to project content onto three Screens, notice the content becomes larger as the Screens move further away from the emitter point

Creating a Perspective mapping

Follow the instructions in the sub-chapter Creating a new mapping and select Perspective from the menu of different mapping types.

Perspective mapping properties (in addition to Common mapping type properties)

Eye point

The Eye point specifies the source point (emitting point) of the Perspective mapping.

Rotation

The Rotation parameter specifies the rotation of the frustrum of the Perspective mapping (i.e. the aiming point of the Perspective mapping).

Field of view

Defines the field of view of the Perspective mapping, in degrees (i.e. the size of the mapping coverage).

10.9 Cylindrical mapping

The Cylindrical mapping type wraps content around a cylinder and fires it outwards (or inwards) onto the selected screens.

Similar to the Parallel mapping and the Perspective mapping types, the content is being ‘virtually projected’ from the surfaces of the cylinder, both inwards and outwards.

Cylindrical mapping type used to wrap content around a cylinder and fire it outwards (or inwards) onto the selected Screens

Creating a Cylindrical mapping

Follow the instructions in the sub-chapter Creating a new mapping and select Cylindrical from the menu of different mapping types.

Cylindrical mapping properties (in addition to Common mapping type properties)

Output

By default, this is set to colour. This implies that red, green and blue content channels are sent to the red/green/blue colour output channels of the screen (or converted to cyan, magenta and yellow if the output fixtures are CMY). However, content can also be channelled to other channels in the case of DMX-based fixtures. Currently, this is a beta functionality, so for the moment you are advised to leave this set to colour.

Anchor

As with the Parallel mapping type, you can anchor the cylinder around the centre, or the top or bottom points. Resize and rotation operations will keep the anchor point in the same place.

Centre

This controls the stage position of the centre of the cylinder (in other words, its anchor point).

Size

This controls the size of the cylinder in meters, on the x, y and z axes respectively. The y property (the second value) controls the height; the two other properties control the radii in the x and z axes. Setting x and z to the same value keeps the cylinder’s cross‐section circular; setting them to different values makes it elliptical.

Rotation

This rotates the cylinder around the anchor point; specified in degrees of rotation around the x, y and z axes respectively.

Using the cylindrical mapping type

In addition to the property explanations provided in the sub-chapter Common mapping type properties, it is important to:

Base the resolution of the Cylindrical mapping on the aspect between the circumference of the cylinder and the height of the screen. The circumference can be calculated by taking the diameter * pi, = size x * 3.14. Set the size x and z to the same value to establish as perfect circular shape.

10.10 Radial mapping

The Radial mapping is similar to the Cylindrical mapping type, except that the content surface runs from the central axis to the cylinder rim, rather than being wrapped around the outside of the cylinder. Any fixtures or pixels inside the cylinder will therefore be mapped according to their height within the cylinder (y coordinate) and their distance from the cylinder’s axis (x coordinate). Fixtures outside of the cylinder are not affected.