Tài liệu 3D Game Programming All in One- P9 ppt

//============================================================================ function Toggle3rdPPOVLook( %val ) // // Enable the "free look" feature. As long as the mapped key is pressed, // the player can view his avatar by moving the mouse around. // { if ( %val ) $mvFreeLook = true; else $mvFreeLook = false; } function Toggle1stPPOV(%val) // // switch between 1st and 3rd person point-of-views. // { if (%val) { $firstPerson = !$firstPerson; } } //============================================================================ // keyboard control mappings //============================================================================ // these ones available when player is in game playerKeymap.Bind(keyboard, up, GoAhead); playerKeymap.Bind(keyboard, down, BackUp); playerKeymap.Bind(keyboard, left, GoLeft); playerKeymap.Bind(keyboard, right, GoRight); playerKeymap.Bind( keyboard, numpad0, DoJump ); playerKeymap.Bind( mouse, xaxis, DoYaw ); playerKeymap.Bind( mouse, yaxis, DoPitch ); playerKeymap.Bind( keyboard, z, Toggle3rdPPOVLook ); playerKeymap.Bind( keyboard, tab, Toggle1stPPOV ); // these ones are always available GlobalActionMap.BindCmd(keyboard, escape, "", "quit();"); GlobalActionMap.Bind(keyboard, tilde, ToggleConsole); Client 147 Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. //============================================================================ // The following functions are called from the client common code modules. // These stubs are added here to prevent warning messages from cluttering // up the log file. //============================================================================ function onServerMessage() { } function onMissionDownloadPhase1() { } function onPhase1Progress() { } function onPhase1Complete() { } function onMissionDownloadPhase2() { } function onPhase2Progress() { } function onPhase2Complete() { } function onPhase3Complete() { } function onMissionDownloadComplete() { } Right off the bat, a new ActionMap called playerKeymap is created. This is a structure that holds the mapping of key commands to functions that will be performed—a mechanism often called key binding,or key mapping. We create the new ActionMap with the intent to populate it later in the module. Then we define the 3D control (TS, or ThreeSpace) we call PlayerInterface (because that's what it is), which will contain our view into the 3D world. It's not a complex definition. It basically uses a profile defined in the common code—something we'll explore in a later chapter. If we want to use our mouse to provide view manipulation, we must set the noCursor property of the control to 1, or true . Chapter 4 ■ Game Programming148 Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. Then we define a method for the PlayerInterface control that describes what to do when the control becomes active ("wakes up"). It's not much, but what it does is activate DirectInput in order to grab any user inputs at the keyboard or mouse and then make the playerKeymap bindings active. Next, we define a callback method for the GameConnection object (you know, the one we created back there in control/main.cs). The engine invokes this method internally when the server has established the connection and is ready to hand control over to us. In this method we assign our player interface control to the Canvas we created earlier in the InitializeClient() function in the control/initialize.cs module. After that, we define a whole raft of motion functions to which we will later bind keys. Notice that they employ global variables, such as $mvLeftAction . This variable and others like it, each of which starts with $mv , are seen and used internally by the engine. Then there is a list of key bindings. Notice that there are several variations of the Bind calls. First, there are binds to our playerKeymap , which makes sense. Then there are binds to the GlobalActionMap ; these bindings are available at all times when the program is running, not just when an actual game simulation is under way, which is the case with a normal action map. Finally, there is a list of stub routines. All of these routines are called from within the com- mon code package. We don't need them to do anything yet, but as before, in order to min- imize log file warnings, we create stub routines for the functions. Server The control/server.cs module is where game-specific server code is located. Most of the functionality that is carried in this module is found in the form of methods for the GameConnection class. Here is the control/server.cs module. Type it in and save it as Emaga4\control\server.cs. //============================================================================ // control/server.cs // // server-side game specific module for 3DGPAI1 emaga4 tutorial game // provides client connection management and player/avatar spawning // // Copyright (c) 2003 by Kenneth C. Finney. //============================================================================ function OnServerCreated() // // Once the engine has fired up the server, this function is called // { Server 149 Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. Exec("./player.cs"); // Load the player datablocks and methods } //============================================================================ // GameConnection Methods // Extensions to the GameConnection class. Here we add some methods // to handle player spawning and creation. //============================================================================ function GameConnection::OnClientEnterGame(%this) // // Called when the client has been accepted into the game by the server. // { // Create a player object. %this.spawnPlayer(); } function GameConnection::SpawnPlayer(%this) // // This is where we place the player spawn decision code. // It might also call a function that would figure out the spawn // point transforms by looking up spawn markers. // Once we know where the player will spawn, then we create the avatar. // { %this.createPlayer("0 0 220 1 0 0 0"); } function GameConnection::CreatePlayer(%this, %spawnPoint) // // Create the player's avatar object, set it up, and give the player control // of it. // { if (%this.player > 0)//The player should NOT already have an avatar object. { // If he does, that's a Bad Thing. Error( "Attempting to create an angus ghost!" ); } // Create the player object %player = new Player() { Chapter 4 ■ Game Programming150 Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. dataBlock = HumanMaleAvatar; // defined in player.cs client = %this; // the avatar will have a pointer to its }; // owner's connection // Player setup %player.setTransform(%spawnPoint); // where to put it // Give the client control of the player %this.player = %player; %this.setControlObject(%player); } //============================================================================ // The following functions are called from the server common code modules. // These stubs are added here to prevent warning messages from cluttering // up the log file. //============================================================================ function ClearCenterPrintAll() { } function ClearBottomPrintAll() { } The first function, OnServerCreated , manages what happens immediately after the server is up and running. In our case we need the player-avatar datablocks and methods to be loaded up so they can be transmitted to the client. Then we define some GameConnection methods. The first one, OnClientEnterGame , simply calls the SpawnPlayer method, which then calls the CreatePlayer method using the hard- coded transform provided. CreatePlayer then creates a new player object using the player datablock defined in con- trol/player.cs (which we will review shortly). It then applies the transform (which we created manually earlier) to the player's avatar and then transfers control to the player. Finally, there are a couple more stub routines. That's the end of them—for now—I promise! Player The control/player.cs module defines the player datablock and methods for use by this datablock for various things. The datablock will use the standard male model, which in this case has been named player.dts. Figure 4.3 shows the standard male avatar in the Emaga4 game world. Player 151 Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. Here is the control/player.cs module. Type it in and save it as Emaga4\control\player.cs. // // control/player.cs // // player definition module for 3DGPAI1 emaga4 tutorial game // // Copyright (c) 2003 by Kenneth C. Finney. // datablock PlayerData(HumanMaleAvatar) { className = Avatar; shapeFile = "~/player.dts"; emap = true; renderFirstPerson = false; cameraMaxDist = 4; mass = 100; density = 10; drag = 0.1; maxdrag = 0.5; maxEnergy = 100; maxDamage = 100; maxForwardSpeed = 15; maxBackwardSpeed = 10; maxSideSpeed = 12; Chapter 4 ■ Game Programming152 Figure 4.3 Player-avatar in Emaga4. Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. minJumpSpeed = 20; maxJumpSpeed = 30; runForce = 4000; jumpForce = 1000; runSurfaceAngle = 70; jumpSurfaceAngle = 80; }; // // Avatar Datablock methods // // function Avatar::onAdd(%this,%obj) { } function Avatar::onRemove(%this, %obj) { if (%obj.client.player == %obj) %obj.client.player = 0; } The datablock used is the PlayerData class. It is piled to the gunwales with useful stuff. Table 4.2 provides a summary description of each of the properties. There are many more properties available for the avatar, which we aren't using right now. We can also define our own properties for the datablock and access them, through an instance object of this datablock, from anywhere in the scripts. Last but not least, there are two methods defined for the datablock. The two basically define what happens when we add a datablock and when we remove it. We will encounter many others in later chapters. Running Emaga4 Once you've typed in all of the modules, you should be in a good position to test Emaga4. Emaga4 is a fairly minimalist program. When you launch tge.exe, you will be deposited directly into the game. Once you have been deposited in the game, you have a small set of keyboard commands available to control your avatar, as shown in Table 4.3. Running Emaga4 153 Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. Chapter 4 ■ Game Programming154 Table 4.2 Emaga4 Avatar Properties Property Description className Defines an arbitrary class that the avatar can belong to. shapeFile Specifies the file that contains the 3D model of the avatar. emap Enables environment mapping on the avatar model. renderFirstPerson When true, causes the avatar model to be visible when in first-person point-of- view mode. cameraMaxDist Maximum distance from the avatar for the camera in third-person point-of- view mode. mass The mass of the avatar in terms of the game world. density Arbitrarily defined density. drag Slows down the avatar through simulated friction. maxdrag Maximum allowable drag. maxEnergy Maximum energy allowed. maxDamage Maximum damage points that can be sustained before the avatar is killed. maxForwardSpeed Maximum speed allowable when moving forward. maxBackwardSpeed Maximum speed allowable when moving backward. maxSideSpeed Maximum speed allowable when moving sideways (strafing). minJumpSpeed Below this speed, you can't make the avatar jump. maxJumpSpeed Above this speed, you can't make the avatar jump. jumpForce The force, and therefore the acceleration, when jumping. runForce The force, and therefore the acceleration, when starting to run. runSurfaceAngle Maximum slope (in degrees) that the avatar can run on. jumpSurfaceAngle Maximum slope (in degrees) that the avatar can jump on, usually somewhat less than runSurfaceAngle. Table 4.3 Emaga4 Navigation Keys Key Description Up Arrow Run forward Down Arrow Run backward Left Arrow Run (strafe) left Right Arrow Run (strafe) right Numpad 0 Jump z Free look (hold key and move mouse) Tab Toggle player point of view Escape Quit game Tilde Open console Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. After you have created all of the modules, you can run Emaga4 simply by double-clicking on Emaga4\tge.exe. You will "spawn" in to the game world above the ground, and drop down. When you hit the ground, your view will shake from the impact. If you turn your player around, using the mouse, you will see the view shown in Figure 4.4. After spawning, you can run around the country- side, admire your avatar with the Tab and z keys, and jump. Moving Right Along You should have a fairly simple game now. I'll be the first to admit that there is not much to do within the game, but then that wasn't the point, really. By stripping down to a bare- bones code set, we get a clearer picture of what takes place in our script modules. By typing in the code presented in this chapter, you should have added the following files in your emaga4 folder: C:\emaga4\main.cs C:\emaga4\control\main.cs C:\emaga4\control\client.cs C:\emaga4\control\server.cs C:\emaga4\control\initialize.cs C:\emaga4\control\player.cs The program you have will serve as a fine skeleton program upon which you can build your game in the manner that you want. By creating it, you've seen how the responsibilities of the client and server portions of the game are divvied out. Moving Right Along 155 Figure 4.4 Looking around the Emaga4 game world. Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. You've also learned that your player's avatar needs to have a programmatic representation in the game that describes the characteristics of the avatar, and how it does things. In the next chapter we will expand the game by adding game play code on both the client and the server sides. Chapter 4 ■ Game Programming156 Team LRN Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. [...]... control/client/interfaces/playerinterface.gui The PlayerInterface control is the interface that is used during the game to display information in real time The Canvas is the container for PlayerInterface Type in the following code and save it as C:\Emaga5\control\client\interfaces\playerinterface.gui new GameTSCtrl(PlayerInterface) { profile = "GuiContentProfile"; horizSizing = "right"; vertSizing = "bottom";...chapter 5 Game Play I n Chapter 4 we created a small game, Emaga4 Well, not really a game more of a really simple virtual reality simulation We created a few important modules to get the ball rolling In this chapter we'll build on that humble beginning and grow toward something with some game play challenge in it, called Emaga5 There will be some tasks to perform (goals) and some things to make... EmagaCh5KitInstall program, it will automatically create the new folder tree for you It's important for you to become familiar with it, so study Figure 5.1 for a few minutes After examining Figure 5.1, take a few moments to run the EmagaCh5KitInstall program You will find it in the 3DGPAi1\RESOURCES folder After it does its business, it will have installed everything except the key modules that we're going... the game are contained in the control/client folder tree The client-specific activities deal with functions like the interface screens and displays, user input, and coordinating game start-up with the server side of the game control/client/client.cs Many features that were in client.cs in the last chapter are now found in other modules The key mapping and interface screen code that were located in this... interface in a modeless manner, so that other controls or objects on the screen will still receive input events they are interested in PlayerInterface::onWake enables capturing mouse and keyboard inputs using DirectInput It then makes the PlayerKeymap key bindings active using the Push method When the PlayerInterface is removed from display, its OnSleep method removes the PlayerKeymap key bindings from... repositioned from this initial size When you resize a container, all of its child objects are resized and repositioned according to their horizSizing and vertSizing properties The resizing action will be applied in a cascading man- ner to all subobjects in the object hierarchy The following property values are available: Center The object is positioned in the center of its container Relative The object... Chapter 5 ■ Game Play Exec("./weapons/crossbow.cs"); } function StartGame() { if ( $Game: :Duration) // Start the game timer $Game: :Schedule = Schedule( $Game: :Duration * 1000, 0, "onGameDurationEnd"); $Game: :Running = true; schedule( 2000, 0, "CreateBots"); } function OnMissionLoaded() { StartGame(); } function OnMissionEnded() { Cancel( $Game: :Schedule); $Game: :Running = false; } function GameConnection::OnClientEnterGame(%this)... MenuScreen in all its glory Figure 5.3 The Emaga5 MenuScreen Team LRN Client Control Modules Profile Sizing Settings: horizSizing and vertSizing These settings are used to define how to resize or reposition an object when the object's container is resized The outermost container is the Canvas; it will have a starting size of 640 pixels by 480 pixels The Canvas and all of the objects within it will... only while the bound key is actually pressed After all the function definitions, we have the actual key bindings With the Bind method, the first parameter is the input type, the second is the key or button identifier, and the third is the name of the function to be called After all the PlayerKeymap bindings, there are a few for GlobalActionMap, which is a globally predefined action map that is always... military aircraft The HUD comprises information and graphics that are projected onto the canopy or a small screen at eye level in front of the pilot This allows the pilot to continue to look outside for threats, while still having instant visual access to flight- or mission-critical information In game graphics the term HUD is used for visual displays that appear in -game, in a fashion that mirrors the real-world . used internally by the engine. Then there is a list of key bindings. Notice that there are several variations of the Bind calls. First, there are binds. map. Finally, there is a list of stub routines. All of these routines are called from within the com- mon code package. We don't need them to do anything