Lights

Light shapes how a render feels. The same model can look like a sunny morning, a cozy evening or a dramatic exhibit, depending only on where the light comes from, how big the source is and what color it has. Rayscaper has four light types:

Point Light: shines in all directions from one point, like a bare bulb.
Spotlight: shines in a cone, like a recessed ceiling light or a track spot.
Directional Light: parallel rays from one direction, like the sun.
Area Light: shines from a flat surface, like a window, an LED panel or a softbox.

A small art gallery at night, lit by downlights on the paintings, a spotlight on a marble bust and a pendant lamp

A gallery lit only by lights you place: IES downlights on the paintings, a spotlight on the bust and a pendant lamp above the bench.

Add lights with the Rayscaper toolbar in SketchUp:

The Rayscaper toolbar in SketchUp with the four light tools: Point Light, Spotlight, Directional Light, and Area Light.

Videos

Light a room at night places the lights of a lounge with the light tools: a point light with two clicks, a spotlight and an area light with three, moves a light with SketchUp’s Move tool and selects one with the light overlays of the render window. To follow along, download its scene, rayscaper-lights.skp (8.5 MB): the lounge at night, without lights. It works with the free version of Rayscaper.

Shape your light goes through the settings of a light up close: color temperature from a warm glow to cool daylight, intensity and radius, the cone angle and falloff of a spotlight, IES light patterns and the spread of an area light. Its scene, rayscaper-light-settings.skp (8.6 MB), is the same lounge with its three lights.

How Light Placement Works

You place a light in SketchUp and set it up in Rayscaper:

Place the light with a light tool. Pick one of the four light tools from the Rayscaper toolbar and click in your model. The light is a SketchUp component: move, rotate or copy it later with SketchUp’s own tools and the render follows. It’s drawn with edges only, so it never shows up in the render, and its arrow points where a spotlight, area light or directional light shines.
Set it up in the Scene Editor. The Lights section of the Scene Editor appears once your scene has a light. Set its intensity, color and the settings of its type there. The render updates as you change them.

Every light tool places its light the same way:

Click to set a reference point, for example the spot on the ceiling below which a pendant hangs. A wireframe preview of the light appears.
Move the mouse to the light position and click. The Measurements box shows the distance from the reference point; type a distance and press Enter to place the light exactly that far away.
For a spotlight, directional light or area light, move the mouse to aim the light and click. An orange ray shows the direction and highlights what it hits. A point light shines in all directions, so it’s done after the second click.

After you place a light, it’s selected so you can edit it right away. The tool stays active (its toolbar button stays pressed), so you can place several lights in a row. Esc cancels the placement in progress; pick another tool, such as Select, when you’re done.

Placement Controls

The light tools work like native SketchUp tools, with inference snapping, axis locking and the Measurements box:

Inference snapping: the cursor snaps to edges, faces, midpoints and other geometry, like any SketchUp drawing tool.
Shift: hold Shift to lock the current inference direction, so the light stays on the inferred line while you move the mouse.
Arrow keys: press an arrow key to lock the movement to an axis: Up for the blue axis (vertical), Right for the red axis and Left for the green axis. Press the same key again to unlock.
Measurements box: after the first click, type a distance and press Enter to place the light at that exact distance from the reference point.

Aiming a Light

To point a spotlight, directional light or area light somewhere else, use Aim Light on the Rayscaper toolbar (also under Extensions > Rayscaper, and Aim Light in the Rayscaper submenu when you right-click selected lights):

With the lights selected, the tool starts aiming them right away. Without a selection, click a light first: it lights up orange under the cursor. A point light shines in all directions, so it can’t be aimed.
Click what the light should point at. A preview of the light and its orange ray follow the mouse, and the light turns when you click. Every selected light turns towards the same point, from where it is.

A light keeps its place and, for an area light, its size; it turns as little as it can, so a rectangular panel stays lined up. Every aim is one step to undo. The tool stays active, so you can click the next light right away. Shift and the arrow keys lock the direction like in the light tools: Up aims a light straight down. A light in a group or component can be aimed while you edit that group or component.

Seeing a Light’s Shape in SketchUp

While Rayscaper renders, SketchUp draws the shape of the light of the selected lights in orange: the cone of a spotlight to the surface it shines on, with a dashed circle inside which it’s at full brightness, the size of a point light, the angle of a directional light and the spread of an area light. Change a setting in Rayscaper and the drawing follows. A light that is off or hidden is drawn in grey. Turn the drawing off under View > Overlays > Rayscaper Light Shapes.

Light Type Comparison

The same gallery, lit by one light type at a time:

The gallery lit by the pendant's point light only

The pendant’s bulb lights the whole room from one spot, brightest close by and fading with distance.

Settings Shared by All Lights

Every light has these settings:

Setting	Description
On	Switches the light on or off, handy to compare the scene with and without it. A light that is hidden in SketchUp (or whose tag is) doesn’t render either, and keeps this setting for when it’s shown again.
Mode	How you set the color: Temperature in Kelvin (realistic) or Color (any RGB color). New lights use Temperature.
Preset	A real light source: sets the intensity, the color temperature and the shape of the light. See Light Presets.
Unit	The unit of Intensity: the one of real lights (lumen, cd/m² or lux, depending on the light) or Watts. The choice holds for every light.
Intensity	How bright the light is. A light keeps it when you change its temperature, like a bulb in another color.

Light Presets

A preset makes a light as bright as the real thing, in the color it has, so you don’t have to guess an intensity. Pick one from Preset at the top of the light’s settings:

Light type	Presets
Point Light	Candle (12 lm), Filament Bulb (250 lm), Bulb 40 W (470 lm), Bulb 60 W (800 lm), Bulb 100 W (1600 lm), Street Light (6000 lm)
Spotlight	LED Downlight (650 lm in a 60° beam), Accent Spot (400 lm, 36°), Narrow Spot (350 lm, 16°), Reading Lamp (450 lm, 90°), Floodlight (3000 lm, 110°)
Area Light	LED Panel (3600 lm), Softbox (10000 lm), Window (daylight of an overcast day), TV Screen
Directional Light	Sun (100000 lx), Low Sun (20000 lx), Moonlight (0.25 lx)

A new light starts as a real one: a point light as a 60 W bulb, a spotlight as an LED downlight, an area light as an LED panel and a directional light as the sun. Each preset shows what it gives in the list. The bulbs are named after the incandescent bulb they replace, like on the box of an LED bulb. A spotlight preset puts its lumen into its beam, so a narrow spot is much brighter in the middle of its beam than a bulb with the same lumen. The Window and TV Screen presets set how bright the surface is (in cd/m²), so they are right at every size: place the window light in the window, facing into the room. Change any setting afterwards and the preset shows Custom.

The presets are as bright as real lights next to Rayscaper’s sky, so they look the way they do in a photo: by day the lamps in a room hardly show, at night they light it. A night render needs more exposure than a day render, like a camera does: keep Auto Exposure on in the post-processing settings. When it is off, the settings of a preset light offer to turn it on. A scene lit only by a candle or by the moon is darker than auto exposure goes; raise its Compensation by about +4 EV for a candle and +6 EV for the moon.

Intensity Units

By default you set the intensity in the unit of real lights, the one on the box of a lamp:

Lumen (lm) for a point light, a spotlight and an area light with Normalize: all the light it gives. A spotlight gives its lumen into its cone, so narrowing the cone makes the beam brighter, like the reflector of a real lamp. In Watts, a spotlight keeps its intensity when you change its cone.
Candela per square meter (cd/m²) for an area light without Normalize: how bright its surface is, the same at every size.
Lux (lx) for a directional light: how much light falls on a surface facing it.

Switch Unit to W to set it in Watts, the unit the renderer uses and older versions of Rayscaper showed. These are radiant Watts on the scale of the sky, not the electrical Watts on a bulb: a 60 W bulb is about 0.26 W, the midday sun about 10 W/m².

Understanding Color Temperature

With Mode set to Temperature, you set the color in Kelvin (K), the way real light sources are rated. A new light takes the temperature of its preset: 2700 K for a point light, 3000 K for a spotlight, 4000 K for an area light and 5600 K for a directional light.

Temperature	Color	Real-World Example
2700 K	Warm orange-yellow	Incandescent bulb, candlelight is even warmer
3000 K	Warm white	Halogen spots, warm LED
4000 K	Neutral white	Office lighting, gallery lighting
5600 K	Daylight white	Midday sun
6500 K	Cool white	Overcast sky

Warm and cozy, like a living room.

Using Custom Colors

When Mode is set to Color, you can pick any RGB color you want. This is useful for:

Colored accent lighting
Neon signs or LED strips
Creative/artistic renders
Matching specific brand colors

Point Light

Point lights are the simplest light type. They emit light equally in all directions from a single point in space, like a bare light bulb hanging from the ceiling or a candle flame.

Best uses: General room lighting, lamps without shades, decorative string lights, candles.

Placing a point light: click to set a reference point, then click again to place the light.

Point Light Settings

Setting	Description
Intensity	Brightness of the light, see Intensity Units.
Radius	Size of the light source in meters, from 0 to 10. Larger lights cast softer shadows. Default 3 cm, the size of a bulb.

Understanding Radius

Real lights have a size. A tiny LED casts crisp shadows, a large frosted globe casts soft ones. Radius gives the light that size:

Radius 0: the light is an infinitely small point and every shadow edge is razor sharp.
Radius above 0: the light is a sphere of that radius. The bigger the sphere, the softer the shadow edges.

The pendant in the gallery has a wire cage around its bulb, and the cage’s shadow shows the effect clearly:

The cage of the pendant casting sharp lines across the walls

A point-sized bulb: the cage throws hard lines across the walls and the ceiling.

Spotlight

Spotlights emit light in a cone shape, making them perfect for focused, directional lighting. Think of recessed ceiling lights, stage spotlights, flashlights, or car headlights.

Best uses: Recessed downlights, track lighting, accent lighting, stage effects, flashlights.

Placing a spotlight: set a reference point, position the light, then aim it at a target.

Spotlight Settings

Setting	Description
Distribution	Cone for a simple cone of light, or IES for a real-world beam pattern. See IES Light Patterns.
Intensity	Brightness of the light, in lumen into its cone or in Watts, see Unit (Cone only)
Radius	Shadow softness in meters, 0-10 (same as point lights)
Cone Angle	Half the width of the beam, 1-90° (Cone only). Default 30°, which gives a 60° beam.
Falloff	How gradually the light fades at the cone edges, 0-1 (0 = hard edge, 1 = soft fade). Default 0.4 (Cone only).
Brightness	Multiplier on the brightness stored in the IES profile. 1.00 uses the profile’s own brightness (IES only).

Understanding Cone Angle and Falloff

These two settings work together to control the spotlight’s shape:

Cone Angle is measured from the center of the beam to its edge, so the full beam is twice as wide. A cone angle of 10° creates a tight 20° beam; 45° gives a wide 90° beam.
Falloff controls the transition at the edge of the cone:
- Falloff = 0: Hard cutoff - light stops abruptly at the cone edge (like a theatrical spotlight with a sharp edge)
- Falloff = 1: Gradual fade - light smoothly fades to darkness at the edges (more natural-looking)
- Falloff = 0.3: A balanced blend that works for most scenarios

The spotlight on the marble bust shows both settings. Cone Angle sets how much it lights:

A narrow spotlight lighting only the head of the bust

A tight 16° beam: only the bust’s head is lit.

Falloff sets how sharp the edge of the beam is. Look at the edge of the light on the plinth:

A spotlight with a hard edge on the plinth

A hard, theatrical edge.

IES Light Patterns

Real light fixtures don’t produce a perfect cone. Their reflectors and lenses shape the beam, which creates the typical scallops on a wall or a bright center with a softer edge. Manufacturers describe that shape in an IES profile. Set Distribution to IES to use one.

Spotlight settings with the IES distribution and the built-in light patterns

A spotlight with the IES distribution. The selected pattern has a checkmark.

Under Light Pattern, pick one of the built-in patterns:

Pattern	Description
Narrow Spot	A focused beam for highlighting small areas or objects.
Medium Spot	A balanced spotlight for general accent lighting.
Wide Flood	A soft, wide beam for lighting larger areas. This is the default.
Elliptical Beam	A wide, oval beam for walls, artwork, or long surfaces.
Wall Wash	Spreads light evenly down a nearby wall.
Batwing	Pushes more light to both sides for a wider, more even spread.

Here are the six patterns on three downlights close to the back wall of the gallery. Each pattern paints a different shape on the wall:

Narrow spot downlights with small pools of light

Small, bright pools of light with little spill on the wall.

To use a profile from a lighting manufacturer, click Import custom IES… and choose an .ies file. Once imported, use Replace… to choose a different file, or Remove to go back to Wide Flood. A preview below the patterns shows the beam shape of the selected profile.

The brightness of an IES light comes from the profile. Use Brightness to scale it: 2.00 doubles it, 0.50 halves it.

Directional Light

Directional lights cast parallel rays from a single direction, as if the light source were infinitely far away. This is how sunlight and moonlight work in the real world - the source is so distant that all rays are essentially parallel.

Best uses: Sunlight, moonlight, any distant light source.

Placing a directional light: set a reference point, position the icon, then set the light direction.

The position only sets where the light’s icon sits in your model. The light comes from infinitely far away, so only its direction matters.

Directional Light Settings

Setting	Description
Intensity	Brightness of the light, see Intensity Units.
Angle	Apparent size of the light source in degrees, from 0 to 30. Larger angles cast softer shadows. Default 0.53°.

Understanding the Angle Parameter

Angle is the size of the sun as seen from your scene, its angular diameter. It doesn’t change the direction of the light, only how soft the shadows are:

The real sun is about 0.53° across, the default.
Smaller angles give sharper shadows.
Larger angles give softer shadows, like sunlight through haze or thin clouds.

Watch the shadow of the window frame on the floor. The further the shadow falls from the window, the more it softens:

Sharp shadows of the window frame on the floor

The real sun: crisp shadows of the window frame.

SketchUp Sun

Instead of manually placing a directional light for sunlight, you can have Rayscaper automatically sync with SketchUp’s built-in shadow system. When enabled, Rayscaper creates a special directional light called SketchUp Sun that follows the sun direction from SketchUp’s Shadows panel.

The “Use SketchUp Sun for Directional Light” option in the Extensions > Rayscaper menu.

To enable SketchUp Sun tracking:

Go to Extensions > Rayscaper in SketchUp’s menu.
Click Use SketchUp Sun for Directional Light to enable it (a checkmark appears when active).

Once enabled, a directional light named “SketchUp Sun” appears in Rayscaper’s light list. This light automatically updates its direction whenever you change the time or date in SketchUp’s Shadows panel.

SketchUp’s Shadow Settings panel controls the sun direction for the SketchUp Sun light.

You can adjust the time of day, date, and location in SketchUp’s Shadows panel (Window > Shadows), and the SketchUp Sun light in Rayscaper will update in real-time to match.

The SketchUp Sun light in Rayscaper’s Scene Editor, showing its settings.

The SketchUp Sun light works like any other directional light - you can adjust its intensity, color temperature, and angle in Rayscaper’s Scene Editor. However, the light direction is controlled by SketchUp’s shadow settings, not manually.

Area Light

Area lights emit from a flat rectangular or elliptical surface, producing the most realistic soft shadows. Unlike point lights where you artificially increase the radius for softer shadows, area lights are physically larger, so the shadow softness varies naturally with distance - objects close to the light have sharper shadows, while distant objects have softer shadows.

Best uses: Windows (daylight coming through), LED panels, softboxes, TV screens, any large glowing surface.

Placing an area light: set a reference point, position the light, then set the emission direction.

Area Light Settings

Setting	Description
Intensity	Brightness of the light, see Intensity Units.
Normalize	Keeps the total light output the same when you resize the light. On by default.
Shape	Rectangle or Ellipse.
Spread	How widely the light spreads from the surface, from 0 to 180°. Default 180°, like a panel.
Width, Height	The size of the light in meters, from 0.01 to 100. Default 0.5 by 0.5 m.

The size of an area light is the size of its component in SketchUp. Change Width or Height in Rayscaper and the light is scaled in SketchUp once you let go of the field, as one step you can undo there. Scaling the light with SketchUp’s Scale tool changes the fields too. The light keeps its center and the way it faces.

To place an area light of a given size, type its width and height in the Measurements box before the first click of the Area Light tool, like for SketchUp’s Rectangle tool: 1.2m,0.6m, or one length for a square. The tool keeps the size for the next lights you place.

An area light inside a group or component is resized in the group or component, so a light in a lamp that you placed several times changes size in every lamp, like its other settings.

Understanding Normalize

The Normalize setting controls how brightness relates to the light’s size:

Normalize ON (default): The total light output stays the same, whatever the size. Making the light bigger spreads that light over a larger surface, so the light itself looks dimmer, but the scene gets about the same amount of light.
Normalize OFF: Each square meter of the light emits the same amount of light. Making the light twice as big doubles its total output, so the scene gets brighter. This is how real light panels behave: a bigger panel of the same type emits more light.

Understanding Spread

The Spread parameter controls the emission angle - how widely the light disperses from the surface:

Spread = 180°: Fully diffuse. The light emits evenly into the whole hemisphere in front of it, like a softbox, a frosted panel or a window on an overcast day.
Spread = 90°: The light is noticeably more focused in front of the surface.
Spread = 0°: The light only travels straight out, perpendicular to the surface, as a beam the size of the light.

Use 180°, the default, for softboxes, windows and glowing panels. Use lower values (10-45°) for fixtures with a grid or louvers that aim their light, or to light only the area straight in front of the light.

A ceiling panel with 180 degree spread lighting the whole room softly

Fully diffuse: the panel lights the whole room softly, like a softbox.

Selecting Lights

Using Light Overlays

When light overlays are enabled, clickable icons appear in the viewport at each light’s position. This makes it easy to select lights directly in your scene without hunting through the light list.

The light overlay button (outlined) and an icon of each light type. The selected area light is orange, the switched-off sun is dimmed. Click any icon to select that light.

Each light type has a distinct icon:

Point lights show a lightbulb icon
Spotlights show a cone icon
Directional lights show a sun icon
Area lights show a rectangle icon

To toggle light overlays, click the light overlay button in the viewport toolbar (the lightbulb icon highlighted in the image above).

Click any light icon in the viewport to select it. Hold Ctrl while clicking to add or remove lights from your selection. Selected lights are highlighted in orange, and disabled lights appear dimmed.

Editing Multiple Lights

You can select and edit multiple lights at once in the Rayscaper scene editor. Hold Ctrl while clicking lights in the list or viewport to select multiple. Any changes you make will apply to all selected lights.

Right-click selected lights in SketchUp while the render window is open, and the Rayscaper submenu has:

Item	What it does
Edit in Rayscaper	Brings the render window to the front with the lights in the light editor.
Turn Off in Rayscaper / Turn On in Rayscaper	Switches the lights off or on, like their On setting. Unlike hiding them, they stay visible in SketchUp.
Aim Light	Starts the Aim Light tool for the selected spotlights, directional lights and area lights.
Change Type	Turns the lights into another type. They keep their place, direction and color. The other settings start from the default preset of the new type (see Light Presets), or come back as they were when a light had that type before. A point light turned into a spotlight shines down. You can undo it like any change in SketchUp.

Quick Reference

Light Type	Best For
Point Light	Lamps, bulbs, candles
Spotlight	Recessed lights, stage lighting, real fixtures (with an IES pattern)
Directional Light	Sun, moon
Area Light	Windows, panels, softboxes

Credits

The example scene on this page is built from CC0 models and textures from Poly Haven.