Projector 3D Node

Projector 3D was designed to be used as a custom light in a 3D scene, not as a direct texturing tool. It projects a 2D image from its position onto all the geometry inside its projection cone.

Typical applications:

• Texturing several 3D objects with a single shared image.
• Applying a matte painting or a background from a camera point of view.
• Image-based rendering (pseudo-IBL) with an environment image.
• Layering textures on a simple primitive (e.g. texturing a cube with several overlapping projections).

Projected textures can slide over moving objects (how a real projector behaves) or stay anchored when you group the projector and the object in the same Merge 3D.

• Effects Library: Tools > 3D > Projector 3D
• Quick add: right-click in the Node Editor → Add Tool > 3D > Projector 3D

• SceneInput (orange) - accepts a 3D scene. The Projector's transforms affect the whole scene downstream.
• ProjectiveImage (white) - required. The 2D image to project. It can come from a MediaIn, a Loader or any 2D output.

Typical workflow:

                   MediaIn ──┐ (image to project)
                              ↓ ProjectiveImage
Shape 3D → Merge 3D ← Projector 3D
              ↓ Camera 3D
          Renderer 3D

The Projector plugs into the Merge 3D with the other elements. Its position and orientation set where the projected light comes from.

Enabled (default: on)

Toggles the effect. Separate from the node's red switch, which bypasses everything.

Color (default: white)

Multiplied with the projected image before projection. Tint it cool blue for a "moonlight" effect, warm yellow for a "tungsten" effect.

Intensity (default: 1.0)

Strength of the projection. In Light / Ambient Light modes, it controls the light intensity. In Texture mode, it scales the texture color.

Angle (in degrees, maximum 90°)

Width of the projection cone (like a spot light). The wider the angle, the larger the covered area, but the less sharp the image.

Decay Type (default: No Falloff)

Attenuation with distance:

• No Falloff - constant intensity regardless of distance.
• Linear - linear attenuation.
• Quadratic - physically correct attenuation (1 / distance²).

Fit Method controls how the rectangular image fits the projection cone (a square pyramid):

• Inside - the image fits entirely inside the cone (possible bars).
• Width - fits to the width; the height may overflow.
• Height - fits to the height; the width may overflow.
• Outside - the image fully covers the cone (possible cropping).
• Stretch - non-uniform distortion to fill it exactly.

This is the crucial choice. Each mode behaves radically differently.

Light (default)

Projects the image as a diffuse/specular light. Requires Lighting to be enabled in the Renderer 3D. Respects surface normals → faces pointing toward the projector receive the projection, the others don't. Watch out for unwanted specular highlights.

Ambient Light

Uses the ambient channel - no specular, so no highlights. Still affected by the normal direction, but more softly. A good compromise for a matte painting that shouldn't look like a spotlight.

Texture

Projects the image as a texture, not a light. It doesn't need lighting, but only works on objects that have a Catcher node in their material (see below). It is the only mode that respects the image's alpha (it cuts the geometry according to the projected alpha).

The Projector can cast shadows like any light:

• Enable Shadow Casting - turns on shadow casting.
• Shadow Color / Density / Map Size - the standard shadow parameters (color, density, shadow map resolution).
• Multiplicative / Additive Bias - to avoid Z-fighting (shadow flicker on aligned surfaces).
• Softness: None (hard shadows), Constant (uniform softness), Variable (with Falloff, Min and Max for softening with distance).

Camera 3D also offers a projection feature (Camera Projection). When should you use which?

Camera 3D - when the projection must match a filmed shot

Better precision on aperture, film back and clipping planes. Ideal to rebuild a shot with its real camera.

Projector 3D - when you want the flexibility of a light

Better control over intensity, color, decay and shadows. Choose it for custom lighting rather than for matching a precise camera.

In Texture mode, the projection only hits objects whose material contains a Catcher node. Without it, no texture appears.

Workflow: plug a Catcher into the material input of the target object (e.g. Shape 3D → MaterialInput). The Catcher acts as a "receiver" for the projection.

Advanced tip: you can plug a Catcher into any channel of a complex material (diffuse, specular, bump, reflection) so the projection behaves specifically like a specular highlight or a projected bump map.

• Matte painting on several planes - a projector placed at the original camera position projects the matte painting onto several Image Plane 3D nodes at different depths. This gives you parallax when you move the actual render camera.
• Texturing a simple 3D set - primitive (cube, plane) + Projector with an architecture photo = a quickly textured "set" without UV mapping.
• Simulating a video projector - Projector + a MediaIn video projected onto a 3D wall (plane). Set the Angle for the cone and enable shadows so obstacles (characters, objects) block the projection.
• Image-based lighting (pseudo-IBL) - Projector with a spherical HDRI in Ambient Light mode, to give the scene a colored mood without placing 10 lights.
• Texture layering - two Projectors casting different textures from different angles onto the same object. Additive, or with alpha in Texture mode.

• Alpha ignored in Light / Ambient Light - if you want the image's alpha to cut the render, only Texture mode works (and it requires a Catcher).
• Lighting off = nothing - in Light / Ambient Light modes, if the Renderer 3D doesn't have Lighting enabled, the projection is invisible.
• Additive overlap - several overlapping Projectors add up their contributions (cumulative energy, which can overexpose).
• To keep the projection anchored to a moving object (a "stuck" texture), group the Projector and the object in the same Merge 3D - they move together.
• Unwanted specular highlights - if you don't want them, switch to Ambient Light mode.
• Pass Through Lights - if you want the projection to reach objects downstream of the Merge, turn on Pass Through Lights on the Merge 3D that contains the Projector.
• To keep the Projector from affecting the entire downstream scene, put it inside a dedicated Merge 3D.