Adding detail to your model

Adding detail to your model

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You will likely want to create progressively more detailed models as you become more proficient with SketchUp. SketchUp contains several features allowing you to quickly create detailed or life-like models. These features include components, materials, shadows, and styles.


SketchUp allows you to paint materials on faces to add detail and realism to your models. Materials are essentially paints that have a colorand optional texture (defined within a image file). For example, a siding material with the color of grey and an appearance or texture simulating real overlapped composite siding. Following is a building painted with grey composite siding and grey shingle roofing materials. A grass material is also used on the ground.

As with components, SketchUp comes with a collection of materials. You can paint these materials on your models using the Paint Bucket tool. Additionally, you can create your own materials within SketchUp (using the color wheel), or by importing texture-like images (such as the image of a wood flooring). In fact, you can import an entire image of a real-world object (such as a picture of a car), and manipulate it over your 3D model to give your model a truly realistic appearance.

Default material
Geometry in SketchUp is assigned a default material as it is created. The default material can be changed by painting the geometry with a material.

Material Transparency
Materials also have a opacity property (a number between 0 and 100%) allowing you to create materials that behave like glass. Paint these materials on faces to create windows.

Faces have two sides. SketchUp materials are normally applied to a single side of a face at a time. Painting a default colored side with transparent material will result in both sides of that face being treated as transparent allowing the surface to be transparent when viewed from both sides. If the back side of a face has already been painted with some non-transparent material, applying a transparent material to the front side will not cause the back side to also display as transparent. Likewise, if you paint the back side of a face with a different transparent material, it will not effect the front side. Thus, by specifically applying a material to both sides, it is possible to have transparent faces that can have different colors and levels of transparency on each side.

Groups and components

Groups and components are entities that can hold other entities. Groups are commonly used to combine several entities into a single entity for the purposes of performing a quick operation on the group (such as a copy or move). For example, you might draw a model, group the entities that compose model and move the entire model. The characteristics of groups are:
  • Quick selection. When you select a Group, all elements within that group are selected as well.
  • Isolation of geometry. Entities within groups are protected from the rest of the model. Geometry outside of the group does not affect the geometry within the group
  • Model organization. Groups can be nested within other groups resulting in hierarchical collection of subgroups.
  • Group material. The group as a whole can be assigned a material of its own, which is separate from the materials painted on individual entities within the group. See the Materials section within this topic for further information.
  • Drawing Axes. Groups maintain their own internal drawing axes.
  • Alignment and Hole Cutting. Groups have a special behavior that allows them to properly align themselves and stick to faces on which they are placed (as well as cut holes in those faces).

Components are just a group with special behaviors, namely behaviors allowing them to be inserted in other models. For example, you might create a model of a car that you want to bring into other SketchUp models, such as the model of a house. Any models you create can be a component.

Components have the following characteristics, in addition to the characteristics of groups:

  • component definition. The component definition is the blueprint that defines the appearance and behavior of all component instances (created when you insert the component in the model). Editing a component instance edits the definition and all instances accordingly. However, some actions, such as scaling an instance, only affects the instance itself.
  • Improved Performance. Components allow SketchUp to more efficiently use your computer's resources because the information necessary to describe a component is only stored once, in the component definition, and then referenced for every component instance.
  • Drawing Axes. Components display their own internal drawing axes when you are editing the component.
  • Alignment and Hole Cutting. You can define alignment and hole cutting behavior when creating components (it is automatically defined for groups).
Note: You can define the characteristics of the component during component creation.

Group and component context
Entities within a group or component are said to exist within the group or component's scope or context. You can modify a group or component as a whole (affecting all of the entities within the group or component) or edit the group or component's individual entities (within the group or component's context). Additionally, you can nest components within other components, groups within components, components within groups and so on. The following image shows a shelf component has been selected (as indicated by the yellow selection color) using the Select tool. This shelf is composed of several subcomponents, such as slats.

The following image shows the shelf component being edited. Notice that it has a dashed bounding box to indicate you are in the component's context. In this case, a subcomponent, one of the slats in the shelf, has been selected. That slat is within the context of the shelf. Also notice that the component's axes are displayed in the lower left-hand corner.

Finally, the following image shows the slate component being edited. Notice now that there is a dashed bounding box around the component, and around the slat being edited. The entities, such as the lines and face, that compose that individual slat are said to be in the context of the slat.

Component collections
Component collections have been created and included with SketchUp to allow you to easily add detail to your models. These components range from standard architectural components (doors, windows, and so on) to people, cars, trees, and geometric shapes. You can also create your own collections of components from pre-existing components or components you create yourself.

Note: Individual components and collections of components are available on the 3D Warehouse.

Component axes
Components have their own axes which, by default, are aligned to the global axes in the drawing area. These axes can be moved affecting component placement in the model.

Cutting and gluing behavior
Components, such as doors and windows, can be designed such that they can be placed on specifically-oriented surfaces such as vertical wall surfaces. This behavior is referred to as the gluing behavior of a component.

Additionally, components can be designed to automatically cut holes in surfaces, such as in the case of a window component being able to cut a hole in a wall. This behavior is referred to as the cutting behavior of a component.

Layers, groups and components
Layers are a mechanism for controlling the visibility of entities within a model. Entities can be assigned to different layers in a model and those layers, and their contents, can be displayed independently. Groups and Components are used to isolate geometry as sub-models within an overall model, such as a component of a chair within a model of a room.

Note: Entities within a group or component can be on several different layers.


A style is a predefined set of display settings that can be applied to a model, and the drawing area, to give it a specific look-and-feel. A style can consist of a specific edge type, face type, sky and background color,watermark,and other drawing area effects (such as the color used to represent selected geometry). SketchUp has multiple styles, some best used while drawing a model (because they don't use any intensive rendering effects), others are best suited for printing or presenting a model (because they use rendering effects to give a model a hand-drawn appearance). For example, a pre-defined style might have an edge type of jitter edges, a face type of hidden line mode, a background color of white, a sky color of blue, a ground color of brown, and so on.

Sketchy edges
SketchUp allows you to apply various edge types, including hand-drawn sketchy edges, to your model. Sketchy edges are edges that can be unique from any other edge style in SketchUp because, unlike other pre-defined edge types, you can create your own sketchy edge using a drawing program like PhotoShop. Sketchy edges are simply a collection of different hand-drawn strokes that, when combined and applied to model, give the a model a unique hand-drawn appearance.

Watermarksare images placed in the background or foreground of the drawing area and span the entire area just as sky and ground. Watermarks are great for creating backgrounds, such as simulating paper textures beneath a model. Watermarks can also be used to place logos and other graphics directly on the screen.


SketchUp allows you to cast shadows on your model as though the model were in a real-world environment. These shadows can be cast based on time of day and virtual location of the model in the real-world. For example, you can set shadows to see exactly what a model of a house would look like at 10:20 am, December 10, in Boulder, Colorado, which is the default location. Finally, SketchUp's shadows are designed to provide dynamic feedback as you change geometry and your camera viewpoint. The shadow casting feature in SketchUp is a great way to give your models a better sense of depth and realism.

Note: While SketchUp's projected shadow angles are accurate, the rendering effect is not intended to be photorealistic. Fortunately, SketchUp can export models to other many other applications that excel at photo-realistic renderings.

Ground shadows
Ground shadows use the faces in your model to create a flattened set of faces on the ground plane. These faces are colored and positioned based on the background color and the angle of the sun. Although faster than face shadows, the illusion that ground shadows provide only works on the ground plane. The following figure shows a model whose geometry all lies on or above the ground plane.

Note: Ground shadows create unexpected geometry, called artifacts, when your model contains geometry beneath the ground plane. Ground shadows works well for models with solid color backgrounds and in which all geometry is above the ground plane.

Face shadows
Face shadows use the sun angle to project shadows based on the location of faces relative to other faces. For example, a shadow is cast on the stairs in the following figure, based on the face of the vertical 3d rectangle. The calculation used to create face shadows is processor-intensive, however, and will slow down performance with large models.

Note: Faces with less than 70 percent opacity are considered transparent, and do not cast shadows. Faces with 70 percent opacity or greater cast shadows. Transparent faces cannot receive shadows. The following image shows a transparent (less than 70% opacity) rectangle that does not cast a shadow (left) and a opaque (70% or greater opacity) rectangle that does cast a shadow (right).

The two shadow systems are designed to be complimentary, and you may often wish to have both types enabled simultaneously.

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