DirectionalLight

Imagine sunlight arriving from so far away that all its rays are parallel. DirectionalLight illuminates surfaces from a single direction without reducing intensity solely because objects are farther from the source gizmo. Use PointLight for a light at a position and SpotLight for a cone.

The key directional control is Rotation in Transform. Turn the light and watch highlights and shadows move across a curved Shape3D or Text3D object. Color and Intensity change the character and strength of the light, not the ray direction.

Translation X/Y/Z does not represent light-to-object distance for a standalone DirectionalLight. Moving the Viewer gizmo cannot produce falloff or point the rays elsewhere. Adjust Rotation instead; Use Target can help establish an orientation.

The node has one optional SceneInput and one Scene output, both carrying scene3d data. DirectionalLight does not produce an RGBA image, so use Renderer3D before displaying a regular 2D result or sending it to MediaOut.

For a straightforward graph, feed geometry, Camera3D and DirectionalLight into separate branches of the same Merge3D: Shape3D/Text3D → Merge3D, DirectionalLight → Merge3D, then Merge3D → Renderer3D → MediaOut. This keeps geometry transforms separate from light orientation.

SceneInput allows the light to sit inline in a 3D chain, but there is an important consequence: the common DirectionalLight Transform also applies to the incoming scene. If Translation unexpectedly moves your objects, inspect SceneInput; leave it unconnected for a typical independent key/rim light.

Viewing DirectionalLight by itself does not reveal an illuminated scene. Load Merge3D into the 3D Viewer and enable Lighting to inspect the shape and direction of the light; enable Shadows there as well when evaluating shadows.

3D Viewer display options and the final Renderer3D settings are separate. Verify Enable Lighting in Renderer3D, and Shadows when needed: a correct 3D preview does not automatically guarantee the same 2D render.

When a 3D scene has no explicit light, Fusion can use its built-in default directional light. Adding DirectionalLight changes that baseline, so an immediate change in scene shading after the first light is connected is not necessarily a defect.

Start with white Color, moderate Intensity and Shadows off. Set an off-axis Rotation until the geometry shows a readable light-to-shadow transition; then tune Intensity and Color. This avoids hiding a direction error with excessive light strength.

DirectionalLight shadows are shadow-map based. In Resolve 21 they require Hardware Renderer in Renderer3D, Enable Shadows on the light, and Shadows in the renderer. Caster/receiver object settings and relevant material behavior must also be compatible.

Shadow Color tints the shadow independently from the light Color. Density controls shadow opacity rather than light strength. Keep the shadow neutral during technical checks and adjust Density once a shadow is present.

Shadow Map Size defines the shadow-map resolution: too little resolution creates jagged edges and loses fine detail. Shadow Map Proxy scales the map down in proxy modes. Check final edge quality outside Proxy rather than judging the reduced-resolution preview alone.

Multiplicative Bias and Additive Bias help prevent self-shadowing and shadow acne. Start with the smallest effective Multiplicative Bias, then make a fine Additive correction. Excessive bias visibly separates contact shadows from the casting object.

Sampling Quality and Shadow Map Size solve different problems: one governs how the map is sampled and the other the map pixel budget. Treat them independently and examine the output at 100% zoom.

Non-Transmissive Materials (called Force All Materials Non-Transmissive in the reference) may speed up shadows by using a Z-only map, but it loses information for colored or transmissive shadows. Check this switch separately on glass and translucent material setups.

Softness filters the edge of an already computed shadow. None keeps it hard, Constant uses Constant Softness, and Variable offers distance-dependent softness through Falloff, Min and Max. Make the shadow map and Bias reliable before softening the edge.

The captured Inspector also shows Variable Fast, Shadow Weight, Tight Projection and Clip Near/Far. Their existence is visible in the UI, but the exact algorithms and tradeoffs are not established by the available textual reference. Do controlled A/B comparisons in your Resolve build rather than inventing their functions.

Transform exposes Translation, Rotation with axis order, Pivot, Use Target and Import Transform. For a standalone directional light, orientation matters most; with SceneInput, that same common Transform also affects incoming geometry.

Nested Merge3D nodes can limit a light’s scope. If some geometry remains unaffected, inspect the scene hierarchy and Pass Through Lights before increasing Intensity or adding another light.

For a readable 3D logo, DirectionalLight makes a useful side key or rim because the ray direction stays consistent across the scene. Add a weaker AmbientLight/DomeLight fill only after the key establishes the desired shape.

When animating time of day or a rotating key, keyframe Rotation or drive orientation with Use Target. Animating standalone Translation alone does not simulate a changing sun direction.

For final checks, compare the same scene in the 3D Viewer and Renderer3D, confirm contact shadows and material response, and watch animated light motion. Inspector screenshots establish visible labels, but cannot replace testing `.setting` files and the render in the target Resolve version.