3D Game Programming All In One (2004)

508 Chapter 17 ■ Making Structures

Figure 17.17 The finished bridge.

Figure 17.16 The Texture Browser.

Building a House

The bridge was nice and certainly useful. But one must admit that it's fairly simple. Of course, if you need a bridge you will probably make something more ornate.

In this section we will go a little bit farther and make something more complex: a house with a door opening and a window and internal lighting.

1.Launch QuArK and open the Torque Map Editor. Delete the default room and save the empty file as C:\QuArK 6.3\torque\tmpquark\maps\house.map.

2.Select the Cube brush and create a cube that measures 260 units in width by 360 units in length by 256 units in height. You can see the dimensions by hovering the cursor over the cube and looking in the lower-left corner of the Map Editor window.

3.Create a smaller brush in front of the first cube, as shown in Figure 17.19. This will be used to create the front stairs.

4.Select the new brush in the lowerleft window, and then right-click to get the pop-up menu and choose Stair. You will see your brush change into a staircase, as shown in Figure 17.20.

5.Select the large brush, right-click

to get the pop-up menu, and

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510 Chapter 17 ■ Making Structures

14.Reshape the Portal brush to be just a little larger than the doorway in width and height, and a little narrower than the doorway in thickness, as you can see in Figure 17.27.

15.In the Tree view, double-click the portal icon (not the poly icon that it contains). A small dialog box will appear; the bottom field is the parameter ambient_light setting for the portal. Choose passes through from the combo box.

16.Using the texture assignment technique you learned in the earlier sections of this chapter, set the portal's texture to NULL.

Next we are going to create another entity—a light entity. The process is similar to the portal entity at first, but a light entity is a point entity, not a brush entity, so things will be just a little different.

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17.As before, go to the Entities panel and find the Torque Entities button. Click it and choose light_*entities, light_omni, as shown in Figure 17.28.

18.A new light entity will be created in the Tree view, and a small rendition of a light bulb will appear in your map. Move it up closer to the ceiling, as you can see in Figure 17.29.

19.Double-click the light_omni

20.Save your work and export it using the methods you learned earlier in the Quick Start section.

21.Use UltraEdit to open the mission file for Emaga6, C:\aEmagaCh6\control\data\maps\ book_ch6.mis.

22.Locate this line:

If the line doesn't exist in the file, then locate this one:

interiorFile = "~/data/structures/hovelb.dif";

Change whichever line you find to reflect your new structure as follows:

interiorFile = "~/data/structures/house.dif";

23.Run Emaga6 and check out your new house, which should be in front of you. Go on inside and see the effect the lighting has.

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512 Chapter 17 ■ Making Structures

Moving Right Along

So, in this chapter you've learned yet another tool. QuArK is an extremely feature-complete tool for creating structures for Torque. You've built the two most common sorts of structures, an outdoor structure (the bridge) and a building with a lighted interior.

Your imagination is the only real limit here—castles, complex underground tunnel systems, factories, playgrounds,

Figure 17.29 The repositioned light entity. and just about anything else can be created with QuArK.

Normally, I would include a reference section for QuArK in this chapter. However, the program has so many features and options that the material is just too hefty to present in the chapter. Instead, I've included the QuArK reference in Appendix D.

In the next chapter, we'll take a look at how to make things for the game world environment.

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chapter 18

Making the Game

World Environment

In many games, having a full suite of character models, buildings, trees, and other visual clutter is still not enough to accomplish the needed sense of immersion. There are a number of other aspects to the game world that come from the world around

us that we often take for granted: the background sky, the appearance of water, the appearance of clouds in motion, and the terrain. Figure 18.1 is a nice serene picture of oceanside forested hills just after sunset. No, it's not a photograph—it's a screen shot from the game Tubettiworld being developed using the Torque Game Engine.

Now way back in Chapter 12 we covered terrains to a certain extent, so you probably have a reasonable sense of what is involved with creating terrains using a height map. In this chapter we will revisit terrains using the more labor-intensive method of manually building up a terrain with the in-game editor. We'll get into that at the end of this chapter.

First, however, we will visit sky, clouds, and water—the environmental triad of computer game ambience.

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514Chapter 18 ■ Making the Game World Environment

take for granted, like clouds, and a color gradient that changes as you move farther away from the horizon. We do this using a construct known as a skybox.

A skybox is a cube that surrounds the game player. The player stands inside the box, and no matter which way he turns, he will see some part of the box as long as it isn't obscured by other in-game objects. The box never rotates, and the sides are always the same distance away from the player no matter how far or how fast he moves. Because of the way the images on the faces of the skybox are created, the player does not have the feeling that he is inside a big cube. The skybox images are on the inside faces of this cube, as you can see in Figure 18.2. The back view has been left out to help illustrate the point.

When using skyboxes, we treat them as if they are infinitely large. Only objects that the player can never reach will look correct, like clouds in the sky or distant mountains. If you limit a player's movement to just viewing from a fixed location, you could even use a skybox for nearby scenery.

Figure 18.3 shows an exploded view of the skybox images and how they relate to each other. Note that the image for the bottom is a black field. If you were depicting an area

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image.

The basic concept is that the smaller the Field of View (FOV), the

higher the resolution you will need for the skybox. This is because as the FOV gets smaller, you are looking farther and at a smaller portion of the skybox image. This smaller portion fills the view, and therefore the pixels are larger. Typical first-person point-of-view games use a 90-degree FOV and often have a 60-degree (or even smaller) zoomed-in view for sniper scopes or binoculars.

For example, if our screen resolution is 800 by 600 pixels and our FOV is 90 degrees, then applying our formula yields this:

maxSkyboxResX = 800 * 1/tan(90/2)

maxSkyboxResX = 800 * 1/1

maxSkyboxResX = 800

It also follows that we don't need to recompute the Y resolution because it will scale proportionally. So for this 800 by 600 pixel display with a 90-degree FOV, the highest resolution we should use for the skybox images is 800 by 600 pixels, by happy coincidence!

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516 Chapter 18 ■ Making the Game World Environment

However, if we want to know the deal for the 60-degree FOV that our player's binoculars provide, we need to recompute that value as follows:

maxSkyboxResX = 800 * 1/tan(60/2) maxSkyboxResX = 800 * 1/ 0.57735 maxSkyboxResX = 800 * 1.732 maxSkyboxResX = 1386

For the Y resolution, the value is 1,039. So if you decide to create a high-resolution skybox, you should probably go with nothing larger than 1,280 by 1,024 pixels. (Most games, including Torque, need the image resolution values to be powers of two.)

Personally, I would go with 1,024 by 1,024 as a reasonable compromise for a maximum resolution. These dimensions would apply to all of your skybox panels in a given skybox. The size you eventually choose for your game will in the end be a judgment call, but by using the previous calculations, not just a hopeful stab in the dark.

Creating the Skybox Images

As with other texture-related issues, there is always the question of where to obtain source material. Once again, you have the option of creating your own by using a digital camera or a camera and scanner combination or by simply drawing your own images.

In this section I will walk you through drawing some clouds on the horizon for your sky- box—this is a common sunny-day sort of scene. Low cumulus clouds in the distance peek just above the horizon, all around you.

1.Open Paint Shop Pro and create a new image by selecting File, New. Fill in the dialog box with 256 for both the height and width of the blank image. Make sure that the color depth is set to 16 million colors (24 bit).

2.Save this blank file as C:\aEmaga6\control\data\maps\front.png.

3.Select the Fill tool.

4.Over in the Materials palette, select the Foreground and Stroke Properties check box, just to the right of the color picker (see Figure 18.7).

5.When the Materials dialog box opens, click the Gradient tab.

6.Make sure the value in the Angle window is set to 0, and then click the Edit button.

7.Set the Gradient scale to have two color mark-

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Skyboxes 517

19.Locate the file in your Emaga6 map folder called C:\aEmaga6\control\data\maps\sky_day.dml. Make a copy of this file in the same directory and name the copy "sky_book.dml".

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