|
|
@@ -1,359 +0,0 @@
|
|
|
-#region File Description
|
|
|
-//-----------------------------------------------------------------------------
|
|
|
-// Game.cs
|
|
|
-//
|
|
|
-// Microsoft XNA Community Game Platform
|
|
|
-// Copyright (C) Microsoft Corporation. All rights reserved.
|
|
|
-//-----------------------------------------------------------------------------
|
|
|
-#endregion
|
|
|
-
|
|
|
-#region Using Statements
|
|
|
-using System;
|
|
|
-
|
|
|
-using Microsoft.Xna.Framework;
|
|
|
-using Microsoft.Xna.Framework.Audio;
|
|
|
-using Microsoft.Xna.Framework.GamerServices;
|
|
|
-using Microsoft.Xna.Framework.Graphics;
|
|
|
-using Microsoft.Xna.Framework.Input;
|
|
|
-using Microsoft.Xna.Framework.Input.Touch;
|
|
|
-using Microsoft.Xna.Framework.Storage;
|
|
|
-using Microsoft.Xna.Framework.Content;
|
|
|
-using Microsoft.Xna.Framework.Media;
|
|
|
-
|
|
|
-#endregion
|
|
|
-
|
|
|
-namespace Aiming
|
|
|
-{
|
|
|
- /// <summary>
|
|
|
- /// this sample showing how to aim one object towards another. In this sample, a
|
|
|
- /// spotlight turns to aim towards a cat that the player controls.
|
|
|
- /// </summary>
|
|
|
- public class AimingGame : Game
|
|
|
- {
|
|
|
- #region Constants
|
|
|
-
|
|
|
- // how fast can the cat move? this is in terms of pixels per frame.
|
|
|
- const float CatSpeed = 10.0f;
|
|
|
-
|
|
|
- // how fast can the spot light turn? this is in terms of radians per frame.
|
|
|
- const float SpotlightTurnSpeed = 0.025f;
|
|
|
-
|
|
|
- #endregion
|
|
|
-
|
|
|
- #region Fields
|
|
|
-
|
|
|
- GraphicsDeviceManager graphics;
|
|
|
-
|
|
|
- // we'll need a spriteBatch to draw the spotlight and cat.
|
|
|
- SpriteBatch spriteBatch;
|
|
|
-
|
|
|
- // these four values control the spotlight and how it draws.
|
|
|
- // first is the actual sprite that we'll draw to represent the spotlight.
|
|
|
- Texture2D spotlightTexture;
|
|
|
- // next is the position of the spotlight on the screen.
|
|
|
- Vector2 spotlightPosition = new Vector2();
|
|
|
- // the origin of the spotlightTexture. The spotlight will rotate around this
|
|
|
- // point.
|
|
|
- Vector2 spotlightOrigin = new Vector2();
|
|
|
- // the angle that the spotlight is currently facing. this is in radians. a value
|
|
|
- // of 0 points to the right.
|
|
|
- float spotlightAngle = 0.0f;
|
|
|
-
|
|
|
-
|
|
|
- // these next three variables control the cat. catTexture is the sprite that
|
|
|
- // represents the cat...
|
|
|
- Texture2D catTexture;
|
|
|
- // ...catPosition is the cat's position on the screen...
|
|
|
- Vector2 catPosition = new Vector2();
|
|
|
- // ...and catOrigin is the origin of catTexture. the sprite will be drawn
|
|
|
- // centered around this value.
|
|
|
- Vector2 catOrigin = new Vector2();
|
|
|
-
|
|
|
- #endregion
|
|
|
-
|
|
|
- #region Initialization
|
|
|
-
|
|
|
-
|
|
|
- public AimingGame()
|
|
|
- {
|
|
|
- graphics = new GraphicsDeviceManager(this);
|
|
|
-
|
|
|
- Content.RootDirectory = "Content";
|
|
|
-
|
|
|
-#if WINDOWS_PHONE
|
|
|
- graphics.SupportedOrientations = DisplayOrientation.Portrait;
|
|
|
- graphics.PreferredBackBufferWidth = 480;
|
|
|
- graphics.PreferredBackBufferHeight = 800;
|
|
|
-
|
|
|
- TargetElapsedTime = TimeSpan.FromTicks(333333);
|
|
|
-
|
|
|
-#else
|
|
|
- graphics.PreferredBackBufferWidth = 320;
|
|
|
- graphics.PreferredBackBufferHeight = 480;
|
|
|
-#endif
|
|
|
- graphics.IsFullScreen = true;
|
|
|
- }
|
|
|
-
|
|
|
-
|
|
|
- protected override void Initialize()
|
|
|
- {
|
|
|
- base.Initialize();
|
|
|
-
|
|
|
- // once base.Initialize has finished, the GraphicsDevice will have been
|
|
|
- // created, and we'll know how big the Viewport is. We want the spotlight
|
|
|
- // to be centered in the middle of the screen, so we'll use the viewport
|
|
|
- // to calculate where that is.
|
|
|
- Viewport vp = graphics.GraphicsDevice.Viewport;
|
|
|
- spotlightPosition.X = vp.X + vp.Width / 2;
|
|
|
- spotlightPosition.Y = vp.Y + vp.Height / 2;
|
|
|
-
|
|
|
- // we'll use the viewport size again, this time to put the cat on the
|
|
|
- // screen. He goes 1/4 of the way across and halfway down.
|
|
|
- catPosition.X = vp.X + vp.Width / 4;
|
|
|
- catPosition.Y = vp.Y + vp.Height / 2;
|
|
|
- }
|
|
|
-
|
|
|
-
|
|
|
- /// <summary>
|
|
|
- /// Load your graphics content.
|
|
|
- /// </summary>
|
|
|
- protected override void LoadContent()
|
|
|
- {
|
|
|
- // load our textures, and create a sprite batch...
|
|
|
- spotlightTexture = Content.Load<Texture2D>("spotlight");
|
|
|
- catTexture = Content.Load<Texture2D>("cat");
|
|
|
- spriteBatch = new SpriteBatch(graphics.GraphicsDevice);
|
|
|
-
|
|
|
- // now that we've loaded our textures, we can use them to calculate some
|
|
|
- // values that we'll use when drawing them. When we draw the spotlight,
|
|
|
- // it needs to rotate around the "source" of the light. since
|
|
|
- // spriteBatch.Draw will rotate sprites around the "origin" parameter,
|
|
|
- // we need spotlightOrigin to be the "source" of the light. Since I drew
|
|
|
- // spotlight.png myself, I happen to know that the source is halfway
|
|
|
- // down the left hand side of the texture.
|
|
|
- spotlightOrigin.X = 0;
|
|
|
- spotlightOrigin.Y = spotlightTexture.Height / 2;
|
|
|
-
|
|
|
- // Next, we want spriteBatch to draw the cat texture centered on the
|
|
|
- // "catPosition" vector. SpriteBatch.Draw will center the sprite on the
|
|
|
- // "origin" parameter, so we'll just calculate that to be the middle of
|
|
|
- // the texture.
|
|
|
- catOrigin.X = catTexture.Width / 2;
|
|
|
- catOrigin.Y = catTexture.Height / 2;
|
|
|
- }
|
|
|
-
|
|
|
-
|
|
|
- #endregion
|
|
|
-
|
|
|
- #region Update and Draw
|
|
|
-
|
|
|
-
|
|
|
- /// <summary>
|
|
|
- /// Allows the game to run logic.
|
|
|
- /// </summary>
|
|
|
- protected override void Update(GameTime gameTime)
|
|
|
- {
|
|
|
- HandleInput();
|
|
|
-
|
|
|
- // clamp the cat's position so that it stays on the screen.
|
|
|
- Viewport vp = graphics.GraphicsDevice.Viewport;
|
|
|
- catPosition.X = MathHelper.Clamp(catPosition.X, vp.X, vp.X + vp.Width);
|
|
|
- catPosition.Y = MathHelper.Clamp(catPosition.Y, vp.Y, vp.Y + vp.Height);
|
|
|
-
|
|
|
- // use the TurnToFace function to update the spotlightAngle to face
|
|
|
- // towards the cat.
|
|
|
- spotlightAngle = TurnToFace(spotlightPosition, catPosition, spotlightAngle,
|
|
|
- SpotlightTurnSpeed);
|
|
|
-
|
|
|
- base.Update(gameTime);
|
|
|
- }
|
|
|
-
|
|
|
- /// <summary>
|
|
|
- /// Calculates the angle that an object should face, given its position, its
|
|
|
- /// target's position, its current angle, and its maximum turning speed.
|
|
|
- /// </summary>
|
|
|
- private static float TurnToFace(Vector2 position, Vector2 faceThis,
|
|
|
- float currentAngle, float turnSpeed)
|
|
|
- {
|
|
|
- // consider this diagram:
|
|
|
- // C
|
|
|
- // /|
|
|
|
- // / |
|
|
|
- // / | y
|
|
|
- // / o |
|
|
|
- // S--------
|
|
|
- // x
|
|
|
- //
|
|
|
- // where S is the position of the spot light, C is the position of the cat,
|
|
|
- // and "o" is the angle that the spot light should be facing in order to
|
|
|
- // point at the cat. we need to know what o is. using trig, we know that
|
|
|
- // tan(theta) = opposite / adjacent
|
|
|
- // tan(o) = y / x
|
|
|
- // if we take the arctan of both sides of this equation...
|
|
|
- // arctan( tan(o) ) = arctan( y / x )
|
|
|
- // o = arctan( y / x )
|
|
|
- // so, we can use x and y to find o, our "desiredAngle."
|
|
|
- // x and y are just the differences in position between the two objects.
|
|
|
- float x = faceThis.X - position.X;
|
|
|
- float y = faceThis.Y - position.Y;
|
|
|
-
|
|
|
- // we'll use the Atan2 function. Atan will calculates the arc tangent of
|
|
|
- // y / x for us, and has the added benefit that it will use the signs of x
|
|
|
- // and y to determine what cartesian quadrant to put the result in.
|
|
|
- // http://msdn2.microsoft.com/en-us/library/system.math.atan2.aspx
|
|
|
- float desiredAngle = (float)Math.Atan2(y, x);
|
|
|
-
|
|
|
- // so now we know where we WANT to be facing, and where we ARE facing...
|
|
|
- // if we weren't constrained by turnSpeed, this would be easy: we'd just
|
|
|
- // return desiredAngle.
|
|
|
- // instead, we have to calculate how much we WANT to turn, and then make
|
|
|
- // sure that's not more than turnSpeed.
|
|
|
-
|
|
|
- // first, figure out how much we want to turn, using WrapAngle to get our
|
|
|
- // result from -Pi to Pi ( -180 degrees to 180 degrees )
|
|
|
- float difference = WrapAngle(desiredAngle - currentAngle);
|
|
|
-
|
|
|
- // clamp that between -turnSpeed and turnSpeed.
|
|
|
- difference = MathHelper.Clamp(difference, -turnSpeed, turnSpeed);
|
|
|
-
|
|
|
- // so, the closest we can get to our target is currentAngle + difference.
|
|
|
- // return that, using WrapAngle again.
|
|
|
- return WrapAngle(currentAngle + difference);
|
|
|
- }
|
|
|
-
|
|
|
- /// <summary>
|
|
|
- /// Returns the angle expressed in radians between -Pi and Pi.
|
|
|
- /// </summary>
|
|
|
- private static float WrapAngle(float radians)
|
|
|
- {
|
|
|
- while (radians < -MathHelper.Pi)
|
|
|
- {
|
|
|
- radians += MathHelper.TwoPi;
|
|
|
- }
|
|
|
- while (radians > MathHelper.Pi)
|
|
|
- {
|
|
|
- radians -= MathHelper.TwoPi;
|
|
|
- }
|
|
|
- return radians;
|
|
|
- }
|
|
|
-
|
|
|
- /// <summary>
|
|
|
- /// This is called when the game should draw itself.
|
|
|
- /// </summary>
|
|
|
- protected override void Draw(GameTime gameTime)
|
|
|
- {
|
|
|
- GraphicsDevice device = graphics.GraphicsDevice;
|
|
|
-
|
|
|
- device.Clear(Color.Black);
|
|
|
-
|
|
|
- // draw the cat.
|
|
|
- spriteBatch.Begin();
|
|
|
- spriteBatch.Draw(catTexture, catPosition, null, Color.White,
|
|
|
- 0.0f, catOrigin, 1.0f, SpriteEffects.None, 0.0f);
|
|
|
- spriteBatch.End();
|
|
|
-
|
|
|
- // Start sprite batch with additive blending, and draw the spotlight.
|
|
|
- // Additive blending works very well for effects like lights and fire.
|
|
|
- spriteBatch.Begin(SpriteSortMode.Deferred, BlendState.Additive);
|
|
|
- spriteBatch.Draw(spotlightTexture, spotlightPosition, null, Color.White,
|
|
|
- spotlightAngle, spotlightOrigin, 1.0f, SpriteEffects.None, 0.0f);
|
|
|
- spriteBatch.End();
|
|
|
-
|
|
|
- base.Draw(gameTime);
|
|
|
- }
|
|
|
-
|
|
|
-
|
|
|
- #endregion
|
|
|
-
|
|
|
- #region Handle Input
|
|
|
-
|
|
|
-
|
|
|
- /// <summary>
|
|
|
- /// Handles input for quitting the game.
|
|
|
- /// </summary>
|
|
|
- void HandleInput()
|
|
|
- {
|
|
|
-#if WINDOWS_PHONE
|
|
|
- KeyboardState currentKeyboardState = new KeyboardState();
|
|
|
-#else
|
|
|
- KeyboardState currentKeyboardState = Keyboard.GetState();
|
|
|
-#endif
|
|
|
- GamePadState currentGamePadState = GamePad.GetState(PlayerIndex.One);
|
|
|
- MouseState currentMouseState = Mouse.GetState();
|
|
|
- TouchCollection currentTouchState = TouchPanel.GetState();
|
|
|
-
|
|
|
- // Check for exit.
|
|
|
- if (currentKeyboardState.IsKeyDown(Keys.Escape) ||
|
|
|
- currentGamePadState.Buttons.Back == ButtonState.Pressed)
|
|
|
- {
|
|
|
- Exit();
|
|
|
- }
|
|
|
- // check to see if the user wants to move the cat. we'll create a vector
|
|
|
- // called catMovement, which will store the sum of all the user's inputs.
|
|
|
- Vector2 catMovement = currentGamePadState.ThumbSticks.Left;
|
|
|
-
|
|
|
- // flip y: on the thumbsticks, down is -1, but on the screen, down is bigger
|
|
|
- // numbers.
|
|
|
- catMovement.Y *= -1;
|
|
|
-
|
|
|
- if (currentKeyboardState.IsKeyDown(Keys.Left) ||
|
|
|
- currentGamePadState.DPad.Left == ButtonState.Pressed)
|
|
|
- {
|
|
|
- catMovement.X -= 1.0f;
|
|
|
- }
|
|
|
- if (currentKeyboardState.IsKeyDown(Keys.Right) ||
|
|
|
- currentGamePadState.DPad.Right == ButtonState.Pressed)
|
|
|
- {
|
|
|
- catMovement.X += 1.0f;
|
|
|
- }
|
|
|
- if (currentKeyboardState.IsKeyDown(Keys.Up) ||
|
|
|
- currentGamePadState.DPad.Up == ButtonState.Pressed)
|
|
|
- {
|
|
|
- catMovement.Y -= 1.0f;
|
|
|
- }
|
|
|
- if (currentKeyboardState.IsKeyDown(Keys.Down) ||
|
|
|
- currentGamePadState.DPad.Down == ButtonState.Pressed)
|
|
|
- {
|
|
|
- catMovement.Y += 1.0f;
|
|
|
- }
|
|
|
-
|
|
|
- //Move toward the touch point. We slow down the cat when it gets within a distance of CatSpeed to the touch point.
|
|
|
- float smoothStop = 1;
|
|
|
-
|
|
|
- //if (currentTouchState != null )
|
|
|
- {
|
|
|
- if (currentTouchState.Count > 0)
|
|
|
- {
|
|
|
- Vector2 touchPosition = currentTouchState[0].Position;
|
|
|
- if (touchPosition != catPosition)
|
|
|
- {
|
|
|
- catMovement = touchPosition - catPosition;
|
|
|
- float delta = CatSpeed - MathHelper.Clamp(catMovement.Length(), 0, CatSpeed);
|
|
|
- smoothStop = 1 - delta / CatSpeed;
|
|
|
- }
|
|
|
- }
|
|
|
- }
|
|
|
-
|
|
|
- Vector2 mousePosition = new Vector2(currentMouseState.X, currentMouseState.Y);
|
|
|
- if (currentMouseState.LeftButton == ButtonState.Pressed && mousePosition != catPosition)
|
|
|
- {
|
|
|
- catMovement = mousePosition - catPosition;
|
|
|
- float delta = CatSpeed - MathHelper.Clamp(catMovement.Length(), 0, CatSpeed);
|
|
|
- smoothStop = 1 - delta / CatSpeed;
|
|
|
- }
|
|
|
-
|
|
|
- // normalize the user's input, so the cat can never be going faster than
|
|
|
- // CatSpeed.
|
|
|
- if (catMovement != Vector2.Zero)
|
|
|
- {
|
|
|
- catMovement.Normalize();
|
|
|
- }
|
|
|
-
|
|
|
- catPosition += catMovement * CatSpeed * smoothStop;
|
|
|
-
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- #endregion
|
|
|
- }
|
|
|
-}
|
CartBlanche
