Frustum Projection Mapping

Last updated 6 August 2026

A frustum projection mapping projects content onto a surface as if it were seen through a virtual camera with a given field of view and aspect ratio. Use it for perspective-correct placement on complex or irregular surfaces — a 16:9 image landing correctly on a curved or angled screen, seen from one particular viewpoint.

Before you start

  • At least one surface in your scene.

  • The field of view and aspect ratio your projection geometry calls for.

Steps

1. Select the surface

Select it in Scene Objects or in the scene view. Its properties appear in the Inspector.

2. Open the Mapping section

Expand Mapping in the Inspector. Existing mappings are listed, with a type dropdown and a Create button underneath.

3. Create a Frustum Projection mapping

Select Frustum Projection in the dropdown and click Create. The mapping is added and edit mode starts immediately. A pyramid-shaped gizmo appears in the scene view showing the frustum's field of view and direction.

4. Set the field of view

Adjust Field of View (horizontal), in degrees — drag the field or type a value. The default is 45.

A wider angle covers more of the surface but stretches content towards the edges; a narrower one gives a tighter, more telephoto projection.

5. Set the aspect ratio

Set Aspect Ratio to match your content. The default is 1.78 for 16:9 — use 1.33 for 4:3, or 2.39 for CinemaScope.

6. Position and orient the frustum

Use Mapping Position, Mapping Rotation and Mapping Scale, or drag the gizmo in the scene view.

  • Position — where the frustum originates.

  • Rotation — which way it points, as Euler angles in degrees.

  • Scale — stretches or compresses the projection volume.

7. Apply

Click Apply to commit. The mapping can now be used as a channel destination in the Sequencer.

Options explained

Option

What it does

Field of View (horizontal)

Horizontal opening angle in degrees. Wider covers more surface. Default 45

Aspect Ratio

Width-to-height ratio of the projected image; sets the vertical field of view relative to the horizontal. Default 1.78

Mapping Position

X, Y, Z position of the frustum origin in scene space

Mapping Rotation

Euler rotation in degrees — the direction the frustum faces

Mapping Scale

Scale factor per axis for the mapping gizmo

Mapping Size

Dimension factor of the mapped region, per axis

Show Grid

Overlays a grid on the surface for checking alignment

View Mapping Gizmo

Shows or hides the pyramid gizmo in the scene view

Flip U / Flip V

Mirrors the projected content horizontally or vertically

UV Offset Mode

How the offset is applied — Center or Border

UV Scaling / UV Offset

Scales or shifts the UV coordinates within the projection, per axis

Use as internal mapping

Forces this mapping to be the surface's internal mapping — used for black-level correction

Common Mistakes

  • Part of the surface receives no content — geometry behind the frustum origin is outside the projection. Only what lies in front of it is mapped, so move or rotate the frustum rather than widening the field of view.

  • Content is stretched horizontally or vertically — Aspect Ratio does not match the source. It sets the vertical field of view from the horizontal, so a mismatch distorts rather than crops.

  • Changes disappear — edit mode has to be closed with Apply. Selecting another object first discards them.

  • Content lands correctly but nothing is visible — the mapping still needs to be chosen as a channel destination in the Sequencer. Creating it does not route anything to it.

Tips

  • Keep the gizmo visible while positioning — it shows the projection volume, which is far easier to aim than the resulting image.

  • A surface can carry several mappings. Combine a frustum mapping for one region with a planar or dome mapping for the rest.

  • Cancel reverts everything since edit mode started; Reset returns the mapping to its defaults.

Edit Mappings — every mapping type and the fields they share

Create Scene for Projection, optionally Stereoscopic — building the scene and surfaces this maps onto

Sequencer — choosing a mapping as a channel destination