Enhancing CAD Drawings with Photoshop phần 8 potx

WORKING WITH THE ENVIRONMENT 251 Figure 7.31 Dragging the Reflection layer into the Glazing layer set 16. Click the Reflection layer and press Ctrl+J to duplicate it. Notice that the copied layer is not part of the clipping group, but retains the layer style effect. Rename this new layer Reflection2 and drag it between the Glass Right and Glass Curved layers. 17. Create a new clipping group. Hold down the Alt key and position your mouse on the interface between layers Reflection2 and Glass Curved. Click when you see the clipping group cursor appear. 18. Adjust Gradient Overlay to show the shading running vertically along the curved glass sur- face. Double-click the f icon of the Gradient Overlay effect under the Reflection2 layer. In the Layer Style dialog box, change the Angle to 90°, uncheck Reverse, and click OK. 19. Make another copy of the reflection and set up a new clipping group for Glass Left. Click the Reflection2 layer and press Ctrl+J to duplicate it. Rename this Reflection3, drag it down in the Layers palette, and drop it just above Glass Left. 20. Set up a clipping group between the Reflection3 and Glass Left layers. Figure 7.32 shows the Glazing layer set after all the reflection clipping groups are set up. 21. Use the opacity of the various reflection layers to shade the various planes of the building dif- ferently. Select the Reflection3 layer and change its opacity to 50%. Select the Reflection2 layer and set its opacity to 65%. 4386.book Page 251 Monday, November 15, 2004 3:27 PM 252 CHAPTER 7 CREATIVE COMPOSITING Figure 7.32 The Glazing layer set with clipping groups 22. To simulate refraction and the imperfections of glass, you can optionally distort the reflection layers. Select the Reflection layer. Choose Filter  Distort  Glass. The Filter Gallery dialog box opens showing the Glass filter. Change the Distortion slider to 4 and the Smoothness to 5 (see Figure 7.33). Click OK to apply the filter. 23. Select the Reflection2 layer and press Ctrl+F to reapply the last-used filter (Glass). Select the Reflection3 layer and press Ctrl+F again. 24. Save your work as CompositingProject3.psd. If you’re going to continue working through the following sections, you can leave this file open for now. Figure 7.33 Distorting the glass 4386.book Page 252 Monday, November 15, 2004 3:27 PM MAKING ADJUSTMENTS WITH CLIPPING GROUPS 253 Making Adjustments with Clipping Groups You might remember from Chapter 1 that you can edit adjustment layers in the layer stack (as com- pared with adjustments). Adjustment layers are preferable because they allow you to try things out without having to commit to them. You can change your mind later and alter the parameters of an adjustment layer or throw it away without permanently affecting the pixels of your image. Normally, adjustment layers affect all the layers below them in the Layers palette. That’s fine if you want to increase the brightness of many layers at once, for example. Just add a Brightness/Contrast adjustment layer, and it will affect everything below it in the layer stack. On the other hand, what if you want the increased flexibility of an adjustment layer, but want to affect only a single layer? Simple—create a clipping group with the adjustment layer and a masked layer. Here’s how this works: 1. If you have CompositingProject3.psd open from the previous exercise, you can continue here; if not, open that file from your hard drive before continuing. 2. Select the Masonry layer. Add a Brightness/Contrast adjustment layer by clicking Create New Fill or Adjustment Layer at the bottom of the Layers palette. In the Brightness/Contrast dialog box, drag the Brightness slider to +15, drag the Contrast slider to +30, and click OK. 3. Notice that the Masonry layer looks better, but the Ground and Background layers were affected and look too bright. Hold down the Alt key and position your mouse on the interface between the Brightness/Contrast adjustment layer and the Masonry layer. Click when you see the clipping group cursor appear. Now the adjustment layer only affects the Masonry layer. 4. Select the Ground layer. Apply a Hue/Saturation adjustment layer. Drag the Saturation slider to –50 and Lightness to +10. Click OK to close the Hue/Saturation dialog box. 5. Create a clipping group between the Hue/Saturation adjustment layer and the Ground layer. 6. Leave the file open for work in the next section. 4386.book Page 253 Monday, November 15, 2004 3:27 PM 254 CHAPTER 7 CREATIVE COMPOSITING Adding to the Composite Layer styles and adjustments are great because they maintain flexibility for you in the compositing process. You can always go back and tweak as your composition evolves. At some milestone in your process, you can create composite layers that contain collections of work that you have built up from multiple layers. Because a composite layer is an aggregation of work on multiple layers, you lose the ability to edit parameters you may have enjoyed previously. However, the benefit of aggregating content on fewer layers is the ability to affect the composite whole more readily (plus the simplification of the Layers palette). Let’s start cleaning up the Curtain Wall layers by merging them in a composite layer. 1. Continue working here on the CompositingProject3.psd file from the last section. 2. Select the Curtain Wall layer set, right-click its eye icon in the Layers palette, and choose Show/ Hide All Other Layers. Now only the layers in the Curtain Wall set are visible. You can readily see the blue glow that extends beyond the glazing system; you may remember this was origi- nally created by the Outer Glow effect on the Framing layer. 3. Create a new layer and drag it above and out of the Curtain Wall layer set. Rename it Curtain Wall Composite. 4. Press Alt+Shift+Ctrl+E to stamp all visible layers onto the current layer (see Figure 7.34). Figure 7.34 The composite layer stamped from all visible layers To fix the outer glow problem, you’ll need to build up a selection from all the masks of the lay- ers in the Curtain Wall layer set. Later, you’ll create a new mask from this super-selection. 5. Right-click the layer mask thumbnail on the Framing layer. Choose Add Layer Mask To Selec- tion from the context menu. 4386.book Page 254 Monday, November 15, 2004 3:27 PM ADDING TO THE COMPOSITE 255 6. Repeat step 5 on each of the following layers: Glass Right, Glass Curved, and Glass Left. By adding each of these layer masks to the selection, you are building a super-selection containing all the masks in the layer set. 7. Select the Curtain Wall Composite layer and click the Add Layer Mask button at the bottom of the Layers palette. The selection turns into a mask that hides the outer glow pixels. 8. Turn all the layers on. Right-click the eye icon of the Curtain Wall Composite layer, and choose Show/Hide All Other Layers from the context menu. 9. Click the eye icon on the Curtain Wall layer set to toggle it and turn off all the layers it contains. Next, you’ll add a lens flare to the composite layer (see Chapter 3, “Digital Darkroom Skills”). 10. Select the Curtain Wall Composite layer if it’s not already selected. Make sure its layer thumb- nail is selected, not its layer mask thumbnail. 11. Choose Filter  Render  Lens Flare. In the Lens Flare dialog box, click the 50-300mm Zoom radio button, and click a point high up on the glass in the preview area, as shown in Figure 7.35. Click OK to close the Lens Flare dialog box when you’re finished. 12. Drag the Opacity slider down to 80% in the Curtain Wall Composite layer. The entire curtain wall mixes a bit with the background. TIP To further embellish the image, you could optionally add some entourage from the library started in Chapter 3. Now that the project is nearly complete, create a master composite layer representing all of your work to date. This composite layer will live at the top of the Layers palette. 13. Create a new layer and drag it to the top of the Layers palette. Rename this layer Master Composite. Figure 7.35 Adding a lens flare to the composite layer 4386.book Page 255 Monday, November 15, 2004 3:27 PM 256 CHAPTER 7 CREATIVE COMPOSITING 14. Press Alt+Shift+Ctrl+E to stamp all visible onto the new layer. All the other layers are irrele- vant at this point. Still, it is best to keep the underlying layers in case future changes need to be made to this file; this is why we avoided flattening all the layers into one. 15. Choose Filter  Texture  Grain. Select a low intensity in the Filter Gallery dialog box; drag the slider to 10 and click OK. TIP A slight amount of grain or noise helps correct problems with color banding common in inkjet printers. Figure 7.36 shows the final project image. A version of this image is in the color section. Figure 7.36 The completed compositing project Summary You have taken a 3D model from Autodesk VIZ and greatly enhanced its appearance in Adobe Photo- shop though the art of compositing. Hopefully this chapter has introduced you to new avenues for creative expression in your own work. The compositing techniques presented here offer exciting image-based alternatives to the lengthy photo-realistic rendering process of a 3D program. In the next chapter you’ll learn artistic options for illustrating architecture. 4386.book Page 256 Monday, November 15, 2004 3:27 PM Chapter 8 Illustrating Architecture For many years photo-realism has been aggressively marketed by software companies, in trade mag- azines and in computer graphics circles. A 2004 survey at www.cgarchitect.com shows that the architectural visualizations created most often, by a wide margin, are photo-realistic renderings. Although it is certainly true that a photo-realistic 3D rendering can be spectacular and at best is indistinguishable from a photograph, liabilities to this style are worth considering. Every facet of a photo-realistic rendering must be specified, including 3D geometric detail, materials that correctly simulate real-world optics, texture map coordinates, photometric luminaires, and so on. As simula- tions of reality, photo-realistic imagery can be so accurate that nothing is left to the imagination. But it can actually be troublesome to show clients imagery in the early design development stages that is too realistic or pinned down, especially when the intent is to share a common vision and dia- logue, not to debate the index of refraction of the glazing, for example. Non–photo-realistic (NPR) illustrations convey a visual feel for a space when something softer and less determined is called for. NPR illustration stimulates the imagination and draws attention to the essential design ideas of your composition without attempting to be an accurate reality simulation. This chapter is about illustrating architecture with NPR techniques that encompass both VIZ and Photoshop. You will start in Autodesk VIZ with a 3D model and render special channels (ObjectID, Normal, and Zdepth) that are useful in maintaining three-dimensionality and object-selectability in a rendered 2D image. Where appropriate, you’ll also use some of the compositing skills presented in Chapter 7 to render and convert specific objects and shadows in VIZ to masked layers in Photoshop. You’ll improve your illustration skills in the following areas: ◆ Illustrating a 3D Model ◆ Integrating and Painting in Photoshop ◆ Working in Black and White ◆ Reproducing Grayscale Images with Colored Inks Illustrating a 3D Model Start the illustration project in Autodesk VIZ 2005. As mentioned in Chapter 7, a free trial version of Autodesk VIZ 2005 is available at www.autodesk.com . The techniques and automation presented in this chapter are specific to VIZ, and I recommend you use the program or its trial version to walk through these exercises even if you are accustomed to using other 3D software. After you understand this illustration process, you can adapt the procedures to your favorite 3D software package (such as 3ds max, formZ, Lightwave, Maya, and others). 4386.book Page 257 Monday, November 15, 2004 3:27 PM 258 CHAPTER 8 ILLUSTRATING ARCHITECTURE TIP The model used in this chapter is provided in additional file formats ( .3ds , .dxf , and .wrl ) on the companion CD for greater compatibility with other 3D programs. Rendering in VIZ You’ll be making several renderings of the 3D model in VIZ to ultimately integrate into the illustra- tion project for work in Photoshop. All the renderings made in this chapter will be generated from exactly the same point of view, although each will contain different forms of image data. Although the rendering process presented here has some similarities to the compositing process presented in Chapter 7, there are important differences. Instead of rendering each object as a separate image, you’ll render special image channels that allow you to select, mask, and illustrate specific sur- faces in Photoshop. The first step when opening the sample file is to examine it and get a sense of the massing and spa- tial qualities of the design. The 3D model I’ll use here is inspired by William Wurster’s Gregory Farm- house design in Santa Cruz, California (1926). It is a simple residential design centered on an open courtyard featuring spatial sophistication. Once you visualize the 3D model, render an overall shot of the structures and tree, including an alpha channel, to delineate all the object boundaries at once. Make a similar rendering without the tree so that the building is easier to illustrate. To later composite the tree on top of the building, you need to render the tree separately as a matted object. The shadows will also be rendered as a separate element for compositing. 1. Launch Autodesk VIZ 2005. 2. Open the file Farmhouse.max from the Chapter 8 folder on the companion CD. Figure 8.1 shows the 3D model from a bird’s-eye perspective. Notice the camera at eye level on the ground. Use the navigation tools in VIZ to get a feel for the model. Figure 8.1 The 3D model 4386.book Page 258 Monday, November 15, 2004 3:27 PM ILLUSTRATING A 3D MODEL 259 TIP When exploring any 3D model for the first time, examine its objects, modifiers, materials, lights, and so on. You can learn a lot by noticing how other artists structure their scenes. 3. Press C to enter the Camera viewport. 4. Right-click the viewport label (the word Camera ) in the upper-left corner of the viewport. Choose Show Safe Frame from the Viewport menu. This feature displays concentric rectangles in the viewport. The outermost rectangle reveals the aspect ratio and cropped edge of the com- position (see Figure 8.2). This is the point of view you’ll be using in the illustration project. A version of this image is in the color section. 5. Press F10 to open the Render Scene dialog box (see Figure 8.3). Notice the Output Size is already set to 1024 × 768; the Width and Height parameters here control the output size for the entire illustration project. 6. Click the Render button to open the Rendered Frame Window (RFW). The image progressively renders as the scan lines are processed; this should only take a few seconds (see Figure 8.4). NOTE The scene uses a black environment background color to ensure that object boundaries are properly anti-aliased in the alpha channels of composited images. Notice that the RFW shows RGB Alpha in its drop-down list box, indicating that VIZ automat- ically renders the standard color channels plus an alpha channel that stores the object bound- aries in a grayscale channel (see Chapter 7, “Creative Compositing”). Figure 8.2 The camera view 4386.book Page 259 Monday, November 15, 2004 3:27 PM 260 CHAPTER 8 ILLUSTRATING ARCHITECTURE Figure 8.3 The Render Scene dialog box Figure 8.4 The Rendered Frame Window 7. Click the Save Bitmap button in the RFW. Navigate to a project folder on your hard drive and select Targa Image File from the Save As Type drop-down list box in the Browse Images For Output dialog box. Type in the filename FarmhouseandTree.tga and click the Save button to open the Targa Image Control dialog box (see Figure 8.5). If they are not already selected, click the 32 Bits-Per-Pixel radio button, check Compress, and check Pre-Multiplied Alpha. Click OK to save the file. 4386.book Page 260 Monday, November 15, 2004 3:27 PM [...]... the selection (see Figure 8. 22) 275 276 CHAPTER 8 ILLUSTRATING ARCHITECTURE Figure 8. 21 Click with the Magic Wand in the Normal channel, within the wall Click here to select Figure 8. 22 Subtracting from the selection using the ObjectID channel: click within the window pane and each of the shutter areas Click here to subtract window and shutters INTEGRATING AND PAINTING IN PHOTOSHOP 7 Click the Layers... color) Click the Display Alpha Channel button to see the shadow mask (see Figure 8. 8) 20 Close the Shadow RFW, but keep the file open in VIZ Figure 8. 7 The Render Elements tab in the Render Scene dialog box 263 264 CHAPTER 8 ILLUSTRATING ARCHITECTURE Figure 8. 8 Rendering the Shadow element Rendering Special Image Channels with MAXScripts 3D programs generate what I’m calling special image channels internally... window Figure 8. 12 Choosing where to save the rendered images 267 2 68 CHAPTER 8 ILLUSTRATING ARCHITECTURE Now you have rendered the special channels and elements needed for masking in preparation for painting Just as with house painting, most of the effort goes into the prep work You’ll integrate these files into Photoshop and use them to mask off areas that you’ll eventually paint Figure 8. 13 shows all... using the Magic Wand with zero tolerance in noncontiguous mode 8 Press Ctrl+5 to select the ObjectID channel Press W to select the Magic Wand On the Options bar, click New Selection mode, set Tolerance to 0, and clear Contiguous 9 Click a point on the wall of the structure in the background, as shown in Figure 8. 23 Figure 8. 23 Selecting an object using the Magic Wand 277 2 78 CHAPTER 8 ILLUSTRATING ARCHITECTURE... Tolerance of 20, with Anti-Aliased and Contiguous checked Click in the ground area in front of the building 2 Press Shift+F12 to prepare this selection as a masked layer with your action recorded in the Masking With Channels section INTEGRATING AND PAINTING IN PHOTOSHOP Figure 8. 31 The painted Illustration 3 Press D to set the default colors Press Alt+Backspace to fill the layer with black 4 Drag... Figure 8. 32): Pattern Overlay Apply the Green With Fibers pattern from the Color Paper pattern library Use 100% Scale and 100% Opacity Gradient Overlay Overlay Blend Mode, 100% Opacity, Black To White gradient, clear Reverse, Linear Style, 90° Angle, 100% Scale Figure 8. 32 Layer style effects Change the opacity of the Grass layer to 75% after you apply the layer style effects 283 284 CHAPTER 8 ILLUSTRATING... the mask Click the Fog layer thumbnail Press D to set the default colors Press Ctrl+Delete to fill the Fog layer with white Figure 8. 34 The Filter Gallery 285 286 CHAPTER 8 ILLUSTRATING ARCHITECTURE 16 Turn the opacity of the Fog layer down to 75% to reduce the density of the fog Figure 8. 35 shows the completed illustration A version of this image is in the color section 17 Save your work as Farmhouse2.psd... Congratulations on completing the illustration! Hopefully this tutorial has provided you with inspiration to illustrate your own projects with Photoshop Once you practice masking with the special channels, it becomes second nature, and you’ll be able to “paint within the lines” and create illustrations from 3D models easily Figure 8. 35 The completed illustration Working in Black and White Black and white is a... thumbnail Click the Stop Playing/Recording button at the bottom of the Actions palette, and your palette should look like that in Figure 8. 26 INTEGRATING AND PAINTING IN PHOTOSHOP Figure 8. 25 Subtract these areas from the selection with the ObjectID channel Figure 8. 26 After recording the Prepare For Painting action 16 Now much of the prep work is automated For each layer you want to mask, make a selection... green, blue, and gray These are separated by black spacer swatches, so the colors we are interested in line up in columns in the Swatches palette (see Figure 8. 28) Figure 8. 28 The custom color swatches for the farmhouse scene INTEGRATING AND PAINTING IN PHOTOSHOP NOTE Before you begin painting, spend some time choosing a color palette in your own projects; add these colors to the Swatches palette and save . Figure 8. 2 The camera view 4 386 .book Page 259 Monday, November 15, 2004 3:27 PM 260 CHAPTER 8 ILLUSTRATING ARCHITECTURE Figure 8. 3 The Render Scene dialog box Figure 8. 4 The. document window (see Figure 8. 14). Figure 8. 14 Masking the farmhouse with its alpha channel 4 386 .book Page 269 Monday, November 15, 2004 3:27 PM 270 CHAPTER 8 ILLUSTRATING ARCHITECTURE . November 15, 2004 3:27 PM 264 CHAPTER 8 ILLUSTRATING ARCHITECTURE Figure 8. 8 Rendering the Shadow element Rendering Special Image Channels with MAXScripts 3D programs generate