Google SketchUp Cookbook phần 7 pdf

Creating and Editing a Unique Texture | 217 Creating and Editing a Unique Texture8.11 Problem You want to make changes to the material of a specific face. Solution Make a unique texture for that face and then edit the material. Discussion This technique is useful when you have more than one face with a specific material and you want to edit the material of only one of the faces. You make a unique texture for the face you want to change and then edit just that material. The advantage to making a unique texture is that you can add detail to a particular face without changing all faces with the same material, and still keep the geometry simple. For example, you could edit a stone material to have different-colored stones, which would be difficult to achieve by adding extra geometry; you would need different materials for each new face. In this example, you will use your graphics editor to add a sign and paint some of the bricks of just one building in a row of identical buildings. Download my 1. Coffee Shop model from the 3D Warehouse (Figure 8-77). This is a row of shops. You will edit the material of the middle shop. Figure 8-77 Right-click on the middle brick façade and choose 2. Make Unique Texture from the pop-up menu. This adds a new material to the In Model folder of the Materials window, which has the exact shape of the face from which it was taken (Figure 8-78). The name of the new material is derived from the name of the original material, and you can change it if you want. To edit this material, right-click either on the 3. thumbnail in the Materials window (in Windows only) or on the material itself in the model. Choose Edit Texture Image from the pop-up menu. Figure 8-78 218 | Chapter 8: Painting, Materials, and Textures The new material appears in your default graph-4. ics editor. Make some changes to the image. Figure 8-79 shows added text and some painted bricks. Figure 8-79 Save the edited image and return to SketchUp. The 5. middle façade now has the sign and painted bricks (Figure 8-80). Those yellow bricks would have taken more work to create within SketchUp and would have increased the file size. Note The thumbnail for the new material in the Materials window will reflect the changes you make in the graphics editor. Figure 8-80 Using Alpha-Transparent Images8.12 Problem You want to paint with a material that has a transparent background. Solution Use an alpha-transparent image, position it to fit what you’re painting, and hide edges if necessary. Using Alpha-Transparent Images | 219 Note You can use alpha-transparent images to create 2D Face Cam- era components, which are simple 2D cutouts that always face the same direction wherever you orbit, giving the look and feel of a 3D object. For more information and for a discus- sion of a problem with alpha images related to shadows, see Recipe 9.4. The Fencing folder of the Materials window has a few materials with transparent backgrounds. To find more, you can search the 3D Warehouse for alpha images or its variations. The 3D Warehouse also has numerous models of alpha-transparent trees and plants. In the main example, you will create a railing around a balcony by using an alpha-transparent image. In the “Other Uses” section, you’ll see how a single alpha im- age can be used to simplify an Eiffel Tower model, and how to use an alpha image to make a ring of trees. Download my Balcony House model from the 3D 1. Warehouse (Figure 8-81). The railing will be painted onto three vertical walls 2. above the first floor. To make these walls, activate Push/Pull, press the Ctrl/Option key, and then pull up the first floor (Figure 8-82). Erase the top face of this new box, which leaves just 3. the three vertical walls (Figure 8-83). Open the In Model folder of the Materials window 4. and click the iron fence material. The background color of this image is defined to be transparent. Figure 8-81 Figure 8-82 Figure 8-83 Discussion Images with alpha transparency have transparent backgrounds. Most graphics editors enable you to define a certain color as transparent. The .png file format is best for supporting this type of image. Alpha-transparent images are most commonly used for landscaping entourage (trees and plants), for images of people, and for objects such as fences and railings. Alpha-transparent images can be used to paint faces just like any other image, and the transpar- ent parts of the image will be transparent in SketchUp. Edges around alpha-transparent faces may appear to be hovering in space, but you can easily hide edges. The greatest advantage of alpha-transparent images is that they enable you to reduce your file size by using graphics instead of geometry. A 3D tree has a much higher number of edges and faces than a 2D face painted with an alpha-transparent tree. A fence with repeated posts and pickets is much more complex than a 2D face painted with an alpha-transparent fence image. 220 | Chapter 8: Painting, Materials, and Textures Paint one of the railing faces with the iron fence. 5. You can see through the face, but the fence is the wrong size (Figure 8-84). Use texture positioning in Fixed Pins mode, drag-6. ging the red pin to change the starting location, and dragging the green pin to change the scale, so that the image fits the face (Recipe 8.9). Right-click and choose Done when finished. Figure 8-84 Sample the edited material (press the Alt key in 7. Windows or Cmd on the Mac while the Paint tool is active, and click the positioned texture). Then paint the other two faces (Figure 8-85). Just like when you paint with translucent materials (Recipe 8.7), alpha-transparent images are applied to both sides of a face. (But you could override this by painting one side with a different material.) Figure 8-85 To make the railing look more realistic, hide its 8. vertical edges and top horizontal edges (select these edges, right-click on one of them, and choose Hide from the pop-up menu). Figure 8-86 shows the completed railing. Figure 8-86 Using Alpha-Transparent Images | 221 Other Uses For a great example of how using an alpha-transparent image can reduce your file size, download Google’s Eiffel Tower model from the 3D Warehouse (Figure 8-87). It looks complex, but it’s actually a simple model painted with an alpha image. This model can be found in my 3D Warehouse collection for this chapter. Figure 8-87 You can find the image in the In Model folder of the Materials window (Figure 8-88). This image was ap- plied to all four sides, using material positioning in Free Pins mode to adjust the image to fit each face. Free Pins mode is described in Recipe 9.1. Figure 8-88 To see the unpainted model, switch from Shaded with Textures mode to Shaded mode (Figure 8-89). Figure 8-89 222 | Chapter 8: Painting, Materials, and Textures You can also use a single alpha image of a tree to make a ring of trees. Figure 8-90 shows four vertical faces painted with a tiling tree image. When the edges of the faces are hidden, it looks like a group of trees. Figure 8-90 You can use Push/Pull on the faces to make a larger or smaller ring of trees (Figure 8-91). Figure 8-91 Continuing the discussion of painting and materials from Chapter 8, this chapter focuses on using digital photos to paint faces in your model, adding photo- realism and saving modeling time. Using photos to paint faces can reduce the num- ber of geometric elements you need to create. For example, you can take the time and effort to model geometrically accurate windows on the side of a building, or can you simply paint the face with a photo of the side of that building. (If you don’t have an actual photo, a rendering works well, too.) In addition to saving modeling time, using photos this way can greatly reduce file size. For this reason, Google encourages 3D Warehouse contributors to use digital photos on their models whenever possible. Many of the models in the 3D Warehouse are photorealistic, as are many 3D buildings in Google Earth. Some of these models represent extremely complex structures but are modeled in simple geometry painted with photos. To see some examples, open Google Earth with the 3D Buildings layer turned on, and explore any large city. Many buildings are plain gray, but a large number are painted. (For more information, see Chapter 13.) CHAPTER 9 Modeling with Digital Photos This chapter covers all you need to know about painting with digital photos, including how to: Fit a • photo to a face Use photos to make 2D components that • look 3D Edit an imported photo• Use photos to create 3D models• Use Photo Match• Note For the basics of where to find materials and images and how to get them into your model, see Recipes 8.1 and 8.2. 224 | Chapter 9: Modeling with Digital Photos Positioning Textures with Free Pins9.1 Problem You want to fit a material to a face. Solution Use texture positioning in Free Pins mode. Discussion Free Pins mode is used to adjust a material so that it fits perfectly within a face. It is most com- monly used to fit images, such as pictures of windows, doors, façades, or furniture. Free-pin positioning is essentially distorting an image by pulling its corners, to constrain the image to a face. Note The other positioning mode is Fixed Pins, which is used to adjust the location, scale, and skew of a tiling material. Fixed Pins mode is demonstrated in Recipe 8.9. The main example demonstrates how to fit an image of a door to a face. In the “Other Uses” section, you’ll see how fixed pins can fit images to the façade of a building or to faces of a bureau. Download my 1. Custom Door model from the 3D Warehouse (Figure 9-1). A picture of a custom garage door will be painted on the white face. Open the In Model folder of the Materials window, 2. which contains the photo of the door. Paint the door photo onto the face (Figure 9-2). The scale and location are not correct, and the lower edge of the door in the photo is not horizon- tal. You will need to adjust the photo to fit within the door face. Figure 9-1 Figure 9-2 Positioning Textures with Free Pins | 225 Right-click on the door and choose 3. Texture→Position. If you see four multicolored pins (fixed pins), right-click again and choose Fixed Pins to deselect it. Free pins are all yellow and appear in each corner of one of the tiled images (Figure 9-3). Figure 9-3 Free pins are free because they can be picked up 4. and placed anywhere and then dragged into an ex- act position. To “lift” a pin, just click it. Then click again to “drop” it where you want it on the image. To place a pin accurately, you usually need to zoom in very closely to find the correct points on the photo. Using the Zoom window tool and the Previ- ous View tool can speed this process up immensely. In Figure 9-4, one pin was placed at each corner of the rectangular part of the door, because these points are easy to find. (It would be harder to place a pin at the top of the arch.) Note When you lift and drop pins, look for dotted blue helper lines that indicate when a pin is horizontal or vertical from another pin. Drag each pin to a corner of the door face in the 5. model (Figure 9-5). Note Some users prefer to place all of the pins first and then drag all of them into place. Others prefer to place a pin and drag it, and then repeat for subsequent pins. Both methods work fine; it’s a matter of preference. If you need to tweak the image for a better fit, move 6. and drag pins as needed. When the photo looks correct, right-click on the door and choose Done. The rectangular part of the door looks good, but the top of the photo is cut off (Figure 9-6). Figure 9-4 Figure 9-5 Figure 9-6 226 | Chapter 9: Modeling with Digital Photos Use the Move tool to move the top edge of the door 7. up, passing the top of the door in the photo (Figure 9-7). Figure 9-7 Use the 8. Arc tool to trace the top of the door in the photo. Then use the Eraser to trim the rest of the door face. This results in a single door face with the correct photo (Figure 9-8). Figure 9-8 For a more realistic garage door, use Push/Pull to 9. push in the door slightly. The sides of the opening will have the same material as the door, so repaint them with the blue bricks (Figure 9-9). Figure 9-9 [...]... to match the photo (Figure 9 -73 ) Figure 9 -73 Using Photo Match to Paint an Existing Model  |  245 13 Project the textures If you overwrite the existing material on the side of the house, you will get a nicer view of the flowering bush in the corner (Figure 9 -74 ) Figure 9 -74 246  |  Chapter 9: Modeling with Digital Photos Chapter 10 Modeling with Exact Dimensions When SketchUp was first introduced,... painted more or less correctly (Figure 9 -71 ) Note Figure 9 -71 For minor adjustments to the photos, you can position the texture and tweak the free pins 10 The second photo is of a different view of the house Before you import this photo, it is important to orbit so that you are looking at approximately the same view as the second photo (Figure 9 -72 ) Note Figure 9 -72 The origin you use for the first Photo... you to know the exact sizes of all your model’s objects, in SketchUp you can design “by eye.” What many SketchUp users don’t take advantage of, however, is that the application also enables you to create entire models using exact dimensions, despite its deceptively simple tool set, meaning you can use SketchUp as a start-tofinish design tool (SketchUp Pro provides even more sophistication with LayOut,... edits Save the edited image, and the change appears in SketchUp automatically The original image is untouched; the changes apply only to the image within the current SketchUp file In the main example, you’ll see how to fix an image on a billboard In the “Other Uses” section, you’ll see how to make a change to a tiling stone image Editing a Photo  |  2 27 Note Another method of touching up an image is described... the tires Figure 9-46 shows the tires and truck bottom painted black Figure 9-46 Using Free Pins and a Single Image to Paint a 3D Object  |  2 37 9 To paint the front of the truck, sample the material on the side and click the front face (Figure 9- 47) Figure 9- 47 10 Adjust this face by using free pins, and paint the remaining faces by using the same technique Figure 9-48 shows the completed truck with... is still the wrong size (Figure 9-69) Figure 9-69 244  |  Chapter 9: Modeling with Digital Photos 7 To adjust the model’s scale to fit the photo, click and drag along any of the three axes on the photo (Figure 9 -70 ) 8 When the positioning is complete, right-click on the image and choose Done Figure 9 -70 9 In the Sketch Over window, click Project Textures from Photo, which paints the visible faces When... is vertical When the axes look right, right-click on the image and choose Done There is now a scene tab at the top of your SketchUp window (Figure 9-53) If you orbit out of the current view, you will lose the barn picture To get the picture back, you can click this tab Figure 9-53 7 The axes of your model are now aligned to the photo Use the Line tool to trace over the rectangular part of the front of... roof lines on the front face (Figure 9-56) Figure 9-56 240  |  Chapter 9: Modeling with Digital Photos 12 Push back the top of the box to complete the roof (Figure 9- 57) and then switch back to Shaded with Textures mode Note Figure 9- 57 Here’s another way you could complete the roof: starting from the initial box, orbit away from the photo and start the Push/Pull operation Then return to the photo and... image in an external editor, from which you can save the image.) 3 Import WhiteHouse1.jpg as a matched photo (Figure 9- 67) 4 It is easier to adjust the axis bars and origin when the model is out of the way In the Match Photo window, deselect Model The model is now hidden Figure 9- 67 5 Adjust the red and green axis bars, and place the origin in the nearest corner (Figure 9-68) Figure 9-68 6 Select the... Figure 9-13 4 Save and close the photo you edited and return to SketchUp The billboard now shows the improved photo (Figure 9-14) The image in the In Model folder is updated as well, but choosing Undo will bring back the original, unchanged image The changes have not affected the source graphic file, only the graphic internal to the current SketchUp model Figure 9-14 228  |  Chapter 9: Modeling with Digital . 1. Coffee Shop model from the 3D Warehouse (Figure 8 -77 ). This is a row of shops. You will edit the material of the middle shop. Figure 8 -77 Right-click on the middle brick façade and choose. 8 -79 Save the edited image and return to SketchUp. The 5. middle façade now has the sign and painted bricks (Figure 8-80). Those yellow bricks would have taken more work to create within SketchUp. Digital Photos Use the Move tool to move the top edge of the door 7. up, passing the top of the door in the photo (Figure 9 -7) . Figure 9 -7 Use the 8. Arc tool to trace the top of the door in the photo.