Adding Realism to a Model

One of the most interesting aspects of 3-D modeling is the art of applying textures and materials to surfaces of objects. With just a few tools, your model can appear quite realistic.

Before configuring the textures, look through the rendering settings to see how the objects in your model will be visualized.

Changing the render appearance

Rendering refers to the process of converting the mathematical information in a drawing into an image of differing levels of quality and detail. Rendering can be defined by the way the faces of the model are treated, as well as how the edges are displayed.

To change the way the model is displayed, choose options from the View Rendering menu, the Rendering toolbar, or in the Display Settings dialog box, as shown in Figure 33.01. The Display Settings dialog box is a convenient way to set the appearance of your model, rather than using various toolbars and menu commands to set the mode. Also, having the settings collected in one dialog box lets you toggle different effects and settings on and off to see how they affect your model.

Figure 33.1: Choose a display type and specify other display options such as edges and profiles in the Display Settings dialog box.

In the Display Settings dialog box, you can specify the following:

• Rendering mode: Choose one of the modes from the buttons at the top of the dialog box. See the different modes later in this section.

• Edge Effects: Choose an effect and modify its depth as you view the model. You can see the Edge effects later in the section.

• Edge Color: Specify the colors for the edges of the model entities. The default is All same. Click the Edge Color down arrow and choose By material from the drop-down list to use an edge that is colored the same as your model’s objects. If you are working with a geometric model, choose By axis to color the edges red, blue, or green according to which axis an edge lies along.

• Face rendering: You can select the Use sun for shading option to apply default sunlight, or select Enable transparency to use transparent materials, which is described in the Choosing Materials section. Finally, click the Quality down arrow and choose an option from the drop-down list for the display. You can choose Faster, Medium, or Nicer. The Faster display shows the least detail, but renders the quickest, while the Nicer display shows the most detail, but requires more rendering time. Medium shows some detail.

Applying a rendering mode

The model seen in Figure 33.2 shows the same potted plant using the available rendering modes. The modes are as follows:

• Wireframe: This mode shows the model as its structural lines. You can’t see the faces, nor can you use tools such as the Push/Pull tool on a rendered model. Use Wireframe when you want to work with the simple structure of your models as it uses the least time to render the model’s image on-screen.

• Hidden Line: This mode shows the model’s edges and faces, and is another way to work with the structure of the model without taking rendering time. Hidden Line mode is also good for printing a sketch of your model.

• Shaded: This mode shows faces in the model reflecting a light source. You see the color applied to the faces in response to the light. If your model doesn’t have color applied, the default colors are displayed.

• Shaded With Textures: This mode shows both the applied color and an applied texture as they appear reflecting the light source.

• X-Ray: This mode can be used in conjunction with other modes. Applying the X-Ray mode adds a global transparency to the model, showing all faces. You don’t see shadow cast by model faces in X-Ray mode.

• Monochrome: This mode is available from the View Rendering menu. Using Monochrome mode displays the model in the default program color and shows default shading.

Figure 33.2: Choose different methods of displaying your model based on the detail you want to see.

Showing object edges

The Edge effects can add an edgy effect to your drawing, so to speak, making it appear sketch-like or look like a technical drawing, rather than simply rendered, such as the image shown in Figure 33.3. Choose the different effects from the Display Settings dialog box, or from the View Rendering menu.

Figure 33.3: The “before” image of the model shows a chair sitting on a patio with a tree in the background.

To apply any of the edges, follow these steps:

1. Select the check box to specify whether to show Edges, Profiles, or both.

2. Specify a depth for Profiles or leave the default value. All values are shown in pixels.

3. Click to select the Edge Effect you want to use, and specify a depth in pixels as necessary.

4. Toggle different options on and off to view the effects in combination.

The different edge displays are shown in Figure 33.4. They are applied using the sun for shading, and rendered at the Nicer quality setting. All effects use the default pixel values, with the exception of the Extension effect, which uses 10 pixels to show in the figure.

Figure 33.4: Choose from a number of different effects to display the edges of your model.

The edge options you can apply to your drawing include:

• Edges: If you intend to use any edge effects, you must select the Edges check box. Edges follow the lines used in the model and are evenly applied throughout the model. In the figure, you see the edges of the chair and the tree are identified with a simple line.

• Profiles: The Profiles option produces a heavier line that emphasizes the outlines of the major objects in the model. In the figure, for example, the Profiles show the detail at the right edge of the chair’s back.

• Depth cue: Simulate the appearance of perspective using the Depth cue effect, with a heavier line closest to you and thinner lines farther away. The depth cue value specifies the size of the area closest to you in the model. In the example, the lines on the chair are heavier than those used on the tree or patio edges.

• Extension: The Extension effect extends the lines past their endpoints, creating a technical sketch appearance, such as at the edges of the boards making up the chair’s seat and back. The length specified for the effect is the distance of the extension.

• Endpoints: Instead of creating a sketched effect, use the Endpoints effect to highlight the tips of the edges. The area where two edges intersect appear as heavier lines, such as the ends of the chair’s legs, based on the value entered for the effect in pixels.

• Jitter: The Jitter effect produces a pencil sketch appearance. Sketching by hand uses multiple lines that are often offset slightly. Jitter is either added or it isn’t - you don’t specify a depth.

Tip 

The Jitter added to a model has no effect on the drawing of the model. The inference engine takes its cue from the edges and faces in the model, not from an effect applied to the object’s appearance.

Choosing and applying materials

Real life has color and texture, and so too can your models in SketchUp. Use the Paint Bucket tool to apply the color and texture, select paint materials from the Material Browser, and create your own material in the Material Editor.

Caution 

In order to see the materials applied to a model, you must be using the Shaded or Shaded With Textures rendering options, described in the section “Applying a rendering mode” earlier in the chapter.

Applying material to an object’s face

SketchUp offers many default library files containing materials ranging from tile to roof shingles to grass. There are many different rules, keystroke combinations, and processes to consider when applying color to your model. Please refer to the SketchUp help files or online resources for more information.

Follow these steps to apply a material or color to an object:

1. Click the Paint Bucket tool from the Getting Started toolbar, the Principal toolbar, or choose Tools Paint Bucket; you can also choose Window Material Browser. The Materials dialog box appears, and shows the last color or texture applied.

2. Click the Library tab on the Materials dialog box and choose an option. You can also click the directional arrows to the right of the Library drop-down arrow to flip through the library choices. The selected material appears in the swatch at the upper left of the dialog box, as shown in Figure 33.5.

   
   Figure 33.5: Select the material to use for painting faces in your model from the Materials dialog box. The post assembly for the mailbox is painted with a cherry wood color and texture.

3. Move the tool over the model and click to paint the faces of the object with color.

   Tip 

   If the face of an object included in a Group or Component has already been painted, the face won’t accept the new color. In order to recolor, you have to explode the Group or Component and apply the default color, shown as the swatch to the right of the Edit button in the Materials dialog box.

Creating a new material

Instead of using one of the materials in the existing libraries, create your own. In this example, see how to change the default cherry wood material used to fill the mailbox post to a new wood color and texture.

Follow these steps to create a new material from an existing material:

1. Click Create at the top of the Materials dialog box to open the Mix New Material To Paint With dialog box, as shown in Figure 33.6.

   
   Figure 33.6: Develop custom materials in the dialog box based on existing material swatches or new materials.

2. Specify the starting material in the upper-left swatch of the dialog and change if necessary. The original material shown is the cherry wood material.

   Click the eyedropper, and move it over the model to sample a texture from the model if you want.

3. Click the text field at the upper left of the dialog box, and type a name for the new material if you plan to add it to the library.

   A new material is named according to the existing material; the example is named <Woodcherry>1 by default. The new example material is named Wood-walnut.

4. Select or create the color for the new material at the upper right of the dialog box. The example uses a rich dark brown. Choose from several different methods to derive the color, including:

   • Choose a color model from the drop-down list; in the example RGB color is used. Click and drag the sliders, or type values in the RGB fields to define the color.

   • You can also click the eyedropper to sample an existing color on the model.

   • Click the Match Color button at the upper right of the dialog box to open the library to locate and select a color from an existing material.

5. Specify the texture map and its characteristics. The Use texture image option already is selected in the example as it starts from an existing texture, which is named in the field. Choose other options for the texture image including:

   • Click the Folder button to open the Choose Image dialog box. Locate and select the image to use for the texture on your hard drive. Click Open to insert the file into the new material and close the Choose Image dialog box.

   • Click the Lock/Unlock Aspect Ratio button to allow different values for the width and height as in the example.

   • Type measurements in the horizontal and vertical aspect ratio fields to change the measurements for the repeat of the texture’s pattern.

   • Click Reset Color to revert to the original color used by the material on which you are basing the custom material.

   • Select the Colorize option to force all colors to use the same Hue if there are discrepancies in the color, which doesn’t apply in the example.

6. Define the opacity for the material. The default is 100 percent, meaning there is no transparency in the object, and is the value used for the new material. Click the color bar to specify an opacity level, or type a value in the field.

7. Click Add and then Close to close the Mix New Material To Paint With dialog box. In the Materials dialog box, the new material is added to the In Model tab’s thumbnails, as shown in Figure 33.7.

   
   Figure 33.7: The new material is added to the thumbnail list of other materials used in the model.

8. Right-click/Control-click the color swatch to display a shortcut menu and choose Add to Library. The new material, Wood-walnut, is included in the Wood library folder.

9. Continue working with the Materials dialog box, or close it. When you perform another operation, a dialog box appears stating there are changes made to the default library, and do you want to save them. Click Yes.

Note 

You can pare down the number of swatches showing in the Materials dialog box on the In Model tab. Click the arrow at the upper right of the dialog box (shown in Figure 33.5) and choose Purge Unused. Anything you may have experimented with but decided against using is removed from the thumbnails list.

Editing an existing material

You don’t have to start from scratch, nor do you have to save anything that you have customized. If you find an appropriate material in one of the default Library files and apply it to your model, you can make changes to update its appearance automatically.

Follow these steps to edit an existing material:

1. Choose Window Materials Browser to open the Materials dialog box.

2. Click In Model to display thumbnails of the materials currently applied to your model.

3. Select the thumbnail of the material you want to modify, and click Edit to open the Edit Material dialog box.

4. Make the changes as desired. The dialog box is identical to the one shown in Figure 33.6 and discussed in the previous set of steps.

5. Click Close to return to the Materials dialog box, and close the Edit Material dialog box. Reapply the edited material to your model.

Changing the default colors

Rather than using the default program colors, you can change them in a model to suit your tastes. For example, the figures showing the garden model use a grass color as the default for the ground, rather than the default gray-beige color.

To change the default colors for your model, follow these steps:

1. Choose Window Model Info to open the Model Info dialog box. Choose Colors from the column at the left of the dialog box to display the options.

2. Select the Background options to use as the defaults. You can choose Sky, Ground, and to Show ground from below. Drag the slider to adjust the transparency of the ground if you want.

3. Click the color swatch for any color you want to change in the program, either for the geometry or for the background. The Choose Color dialog box appears, as shown in Figure 33.8.

   
   Figure 33.8: Choose specific colors for different aspects of your model in the Choose Color dialog box.

4. Click the upper-left down arrow, and choose a color model from the drop-down list. The default is Color Wheel.

5. Click a location on the Color Wheel (or other model if chosen) to specify a color.

6. Drag the slider at the right of the dialog box to select a lighter or darker version of the color. The selected saturation is seen in the swatch at the left in the dialog box.

7. Make other changes as desired and click OK to close the dialog box and set the color.

Note 

Depending on what you are building, the default colors for the background and sky may not be detailed enough. For example, a model of a house may be enhanced by showing it in its location or using actual views outside windows that you could see during a walkthrough. Use a vertical plane such as a rectangle, and apply a photo of the location on the face.

Editing a texture on an object

You aren’t restricted to using an object at the configured size. If you are applying a material to anything having a flat face, like a cube, you can adjust the appearance of the material on the face.

An example is shown in Figure 33.9. In the figure, the left cube is colored with a solid color. The center cube has a texture applied, which is intended to be used as a label for the object. There are two copies of the image tiled on the front face, as well as the left and top faces. Look at the right figure - the label on the front of the box shows a single label. The material wasn’t changed in its settings; instead, it was changed on the object itself.

Figure 33.9: Adjust the texture on the face of an object to change the appearance.

Decide how and why you need to change a texture. If you want the object changed uniformly, change its dimensions in the Edit Material dialog box. If you decide you want to change it on one face, as in the example, follow these steps to make the changes:

1. Apply the material using a texture image as described in earlier steps.

2. Right-click/Control-click the object and choose Texture Position to open a positioning screen overlaying the image, as shown in Figure 33.10.

   
   Figure 33.10: Choose specific colors for different aspects of your model in the dialog box.

3. Click and drag using the appropriate corner tool to reconfigure the object. Click the pin and move it in any direction to readjust the point at which the effect is applied; click again to anchor the pin to the grid.

   From the upper right, the tools in clockwork order are:

   • Distort: Click the tool and then drag in any direction to change the configuration of the surface.

   • Scale/Rotate: Click the tool and then drag inward or outward to the center of the object to change the scale; drag up or down to rotate the texture.

   • Move: Click the tool and drag to move the texture horizontally or vertically.

   • Scale/Shear: Click the tool and drag inward or outward to the center of the object to change the scale, drag diagonally or vertically to change the angle of the geometry.

4. Click off the grid area to close the tool.

Applying shadows

The final feature in applying a realistic appearance to your models is using shadows. The shadows can be cast based on the time of day and year. Shadows don’t have to be applied and reapplied when you make changes. Fortunately, the shadows update themselves automatically when you change the structure of the model or adjust the camera’s view.

The two types of shadows you can apply in the program are ground and face shadows. Shadows are configured for the entire model, not for a selected object.

Ground shadows are based on a flattened set of the model’s faces and placed on the background based on the angle of the sun. Figure 33.11 shows the impact of applying shadow to a model’s appearance. In the figure, the upper image shows the model without a shadow; the center image shows the model using a ground shadow.

Figure 33.11: The basic model shows more realism when ground shadow is added. Adding face shadows casts a shadow from one object to another, as you see on the fence post.

In three-dimensional space, objects cast shadows on other objects, as well as on the ground. Use the Face shadows in SketchUp to add more realism to your project. Again, like the ground shadow, the angles are based on the location of the sun. The same model using both ground and face shadows is shown at the bottom of Figure 33.11

If you want to configure the shadow settings, choose Window Shadow Settings to open the Shadow Settings dialog box.

Tip 

If you don’t want to make any changes to the shadow, choose View Shadows to apply the existing shadow settings.

You can make these selections in the Shadow Settings dialog box, as shown in Figure 33.12:

• Select Display shadows to show or hide shadow in the model.

• Specify a time and date.

• Drag the Light and Dark sliders to specify how much intensity is used in the shadow.

• Select the shadows to display. Select On faces, On ground, or From edges; faces and ground shadows are realistic in appearance, the From edges shadow casts shadow only from the lines that make up the margins objects.

Figure 33.12: Customize the settings for the intensity and type of shadow for your model.

Caution 

Face shadows require a lot of processing power and will slow down the redraw speed when used in a large model.