Exibir transformações de coordenadas

resumo

Você está manipulando os parâmetros da transformação de coordenadas da vista.

Ambiente operacional

Pré-requisitos

Ambiente operacional

Como trabalhar com a amostra

substância

Sobre as transformações de vista

Consulte a página a seguir para obter uma visão geral das transformações de coordenadas da vista.

• Visualizar sistema de coordenadas

campo

Nesse caso, substituiremos os parâmetros usados para conversão de coordenadas de visualização pela câmera e operaremos os três parâmetros de "posição da câmera", "ponto de olhar da câmera" e "direção da câmera para cima".

/// <summary>
/// カメラの位置
/// </summary>
private Vector3 cameraPosition = new Vector3(2.0f, 4.0f, 20.0f);

/// <summary>
/// カメラの注視点
/// </summary>
private Vector3 cameraTarget = new Vector3(0.0f, 0.0f, 0.0f);

/// <summary>
/// カメラの上方方向回転角度(radian)
/// </summary>
private float cameraUpVectorRotate = 0.0f;

Trabalhando com a câmera

No método Game.Update, usamos o teclado e o controlador para manipular cada parâmetro da câmera. Para obter detalhes de cada operação, consulte "Como fazer" na parte superior desta página. (O código abaixo foi extraído apenas da parte de operação com o gamepad)

GamePadState gamePadState = GamePad.GetState(PlayerIndex.One);

float speed = 0.25f;

// カメラの位置を移動させる
this.cameraPosition.X += gamePadState.ThumbSticks.Left.X * speed;
this.cameraPosition.Y += gamePadState.ThumbSticks.Left.Y * speed;

// カメラの注視点を移動させる
this.cameraTarget.X += gamePadState.ThumbSticks.Right.X * speed;
this.cameraTarget.Y += gamePadState.ThumbSticks.Right.Y * speed;

// カメラの上方方向を回転させる
this.cameraUpVectorRotate -= gamePadState.Triggers.Left * speed * 0.2f;
this.cameraUpVectorRotate += gamePadState.Triggers.Right * speed * 0.2f;

Criando uma matriz de exibição

O método "Matrix.CreateLookAt" é definido com cada parâmetro para criar a matriz de exibição.

O primeiro argumento especifica a posição da câmera, o segundo argumento especifica o ponto de interesse da câmera e o terceiro argumento especifica a direção para cima da câmera.

Em relação ao terceiro argumento, "direção ascendente da câmera", o vetor é calculado girando em torno do eixo Z com base na direção do eixo Y (0,1,0).

// ビューマトリックス作成
Matrix view = Matrix.CreateLookAt(
        this.cameraPosition,
        this.cameraTarget,
        Vector3.Transform(Vector3.Up,
                          Matrix.CreateRotationZ(this.cameraUpVectorRotate))
    );

Matrix.CreateLookAt método

Crie uma matriz de vista para o sistema de coordenadas à direita.

Vector3.Transform método

Transforme o vetor em uma transformação de coordenadas.

Matrix.CreateRotationZ método

Crie uma matriz de rotação em torno do eixo Z.

Um conjunto de matrizes de visualização

A caixa é colocada no ponto de interesse para que a posição do ponto de interesse da câmera seja fácil de entender. Além disso, uma matriz de exibição é definida para cada efeito.

foreach (ModelMesh mesh in this.box.Meshes)
{
    foreach (BasicEffect effect in mesh.Effects)
    {
        // ライトの設定
        effect.EnableDefaultLighting();

        // ボックスの位置をカメラの注視点に合わせる
        effect.World = Matrix.CreateTranslation(this.cameraTarget);

        // ビューマトリックスを設定
        effect.View = view;

        // プロジェクションマトリックス設定
        effect.Projection = projection;
    }

    mesh.Draw();
}

Todos os códigos

using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;
#if WINDOWS_PHONE
using Microsoft.Xna.Framework.Input.Touch;
#endif

namespace ViewMatrix
{
    /// <summary>
    /// ゲームメインクラス
    /// </summary>
    public class GameMain : Microsoft.Xna.Framework.Game
    {
        /// <summary>
        /// グラフィックデバイス管理クラス
        /// </summary>
        private GraphicsDeviceManager graphics = null;

        /// <summary>
        /// スプライトのバッチ化クラス
        /// </summary>
        private SpriteBatch spriteBatch = null;

        /// <summary>
        /// スプライトでテキストを描画するためのフォント
        /// </summary>
        private SpriteFont font = null;

        /// <summary>
        /// ボックスモデル
        /// </summary>
        private Model box = null;

        /// <summary>
        /// XYZモデル
        /// </summary>
        private Model xyz = null;

        /// <summary>
        /// カメラの位置
        /// </summary>
        private Vector3 cameraPosition = new Vector3(2.0f, 4.0f, 20.0f);

        /// <summary>
        /// カメラの注視点
        /// </summary>
        private Vector3 cameraTarget = new Vector3(0.0f, 0.0f, 0.0f);

        /// <summary>
        /// カメラの上方方向回転角度(radian)
        /// </summary>
        private float cameraUpVectorRotate = 0.0f;

        /// <summary>
        /// 自動動作フラグ
        /// </summary>
        private int autoMode = 0;

        /// <summary>
        /// マウスボタン押下フラグ
        /// </summary>
        private bool isMousePressed = false;


        /// <summary>
        /// GameMain コンストラクタ
        /// </summary>
        public GameMain()
        {
            // グラフィックデバイス管理クラスの作成
            this.graphics = new GraphicsDeviceManager(this);

            // ゲームコンテンツのルートディレクトリを設定
            this.Content.RootDirectory = "Content";

#if WINDOWS_PHONE
            // Windows Phone のデフォルトのフレームレートは 30 FPS
            this.TargetElapsedTime = TimeSpan.FromTicks(333333);

            // バックバッファサイズの設定
            this.graphics.PreferredBackBufferWidth = 480;
            this.graphics.PreferredBackBufferHeight = 800;

            // フルスクリーン表示
            this.graphics.IsFullScreen = true;
#endif
        }

        /// <summary>
        /// ゲームが始まる前の初期化処理を行うメソッド
        /// グラフィック以外のデータの読み込み、コンポーネントの初期化を行う
        /// </summary>
        protected override void Initialize()
        {
            // TODO: ここに初期化ロジックを書いてください

            // コンポーネントの初期化などを行います
            base.Initialize();
        }

        /// <summary>
        /// ゲームが始まるときに一回だけ呼ばれ
        /// すべてのゲームコンテンツを読み込みます
        /// </summary>
        protected override void LoadContent()
        {
            // テクスチャーを描画するためのスプライトバッチクラスを作成します
            this.spriteBatch = new SpriteBatch(this.GraphicsDevice);

            // フォントをコンテンツパイプラインから読み込む
            this.font = this.Content.Load<SpriteFont>("Font");

            // ボックスモデルを読み込み
            this.box = this.Content.Load<Model>("Box");

            // XYZ軸モデルを読み込み
            this.xyz = this.Content.Load<Model>("XYZ");
        }

        /// <summary>
        /// ゲームが終了するときに一回だけ呼ばれ
        /// すべてのゲームコンテンツをアンロードします
        /// </summary>
        protected override void UnloadContent()
        {
            // TODO: ContentManager で管理されていないコンテンツを
            //       ここでアンロードしてください
        }

        /// <summary>
        /// 描画以外のデータ更新等の処理を行うメソッド
        /// 主に入力処理、衝突判定などの物理計算、オーディオの再生など
        /// </summary>
        /// <param name="gameTime">このメソッドが呼ばれたときのゲーム時間</param>
        protected override void Update(GameTime gameTime)
        {
            KeyboardState keyState = Keyboard.GetState();
            MouseState mouseState = Mouse.GetState();
            GamePadState gamePadState = GamePad.GetState(PlayerIndex.One);

            // Xbox 360 コントローラ、Windows Phone の BACK ボタンを押したときに
            // ゲームを終了させます
            if (gamePadState.Buttons.Back == ButtonState.Pressed)
            {
                this.Exit();
            }

            // マウスによる自動動作切り替え
            if (this.isMousePressed == false &&
                mouseState.LeftButton == ButtonState.Pressed)
            {
                this.isMousePressed = true;

                this.autoMode = (this.autoMode + 1) % 6;
            }
            this.isMousePressed = mouseState.LeftButton == ButtonState.Pressed;

            float speed = 0.25f;

            // カメラの位置を移動させる
            this.cameraPosition.X += gamePadState.ThumbSticks.Left.X * speed;
            this.cameraPosition.Y += gamePadState.ThumbSticks.Left.Y * speed;
            if (keyState.IsKeyDown(Keys.Left))
            {
                this.cameraPosition.X -= speed;
            }
            if (keyState.IsKeyDown(Keys.Right))
            {
                this.cameraPosition.X += speed;
            }
            if (keyState.IsKeyDown(Keys.Down))
            {
                this.cameraPosition.Y -= speed;
            }
            if (keyState.IsKeyDown(Keys.Up))
            {
                this.cameraPosition.Y += speed;
            }
            if (this.autoMode == 1)
            {
                this.cameraPosition.X = (float)Math.Sin(gameTime.TotalGameTime.TotalSeconds) * 10.0f;
            }
            if (this.autoMode == 2)
            {
                this.cameraPosition.Y = (float)Math.Sin(gameTime.TotalGameTime.TotalSeconds) * 10.0f;
            }

            // カメラの注視点を移動させる
            this.cameraTarget.X += gamePadState.ThumbSticks.Right.X * speed;
            this.cameraTarget.Y += gamePadState.ThumbSticks.Right.Y * speed;
            if (keyState.IsKeyDown(Keys.A))
            {
                this.cameraTarget.X -= speed;
            }
            if (keyState.IsKeyDown(Keys.S))
            {
                this.cameraTarget.X += speed;
            }
            if (keyState.IsKeyDown(Keys.Z))
            {
                this.cameraTarget.Y -= speed;
            }
            if (keyState.IsKeyDown(Keys.W))
            {
                this.cameraTarget.Y += speed;
            }
            if (this.autoMode == 3)
            {
                this.cameraTarget.X = (float)Math.Sin(gameTime.TotalGameTime.TotalSeconds) * 10.0f;
            }
            if (this.autoMode == 4)
            {
                this.cameraTarget.Y = (float)Math.Sin(gameTime.TotalGameTime.TotalSeconds) * 10.0f;
            }

            // カメラの上方方向を回転させる
            this.cameraUpVectorRotate -= gamePadState.Triggers.Left * speed * 0.2f;
            this.cameraUpVectorRotate += gamePadState.Triggers.Right * speed * 0.2f;
            if (keyState.IsKeyDown(Keys.X))
            {
                this.cameraUpVectorRotate -= speed * 0.2f;
            }
            if (keyState.IsKeyDown(Keys.C))
            {
                this.cameraUpVectorRotate += speed * 0.2f;
            }
            if (this.autoMode == 5)
            {
                this.cameraUpVectorRotate = (float)gameTime.TotalGameTime.TotalSeconds;
            }

            // 登録された GameComponent を更新する
            base.Update(gameTime);
        }

        /// <summary>
        /// 描画処理を行うメソッド
        /// </summary>
        /// <param name="gameTime">このメソッドが呼ばれたときのゲーム時間</param>
        protected override void Draw(GameTime gameTime)
        {
            // 画面を指定した色でクリアします
            this.GraphicsDevice.Clear(Color.CornflowerBlue);

            // 深度バッファを有効にする
            this.GraphicsDevice.DepthStencilState = DepthStencilState.Default;

            // ビューマトリックス作成
            Matrix view = Matrix.CreateLookAt(
                this.cameraPosition,
                this.cameraTarget,
                Vector3.Transform(Vector3.Up,
                                  Matrix.CreateRotationZ(this.cameraUpVectorRotate))
            );

            // プロジェクションマトリックス作成
            Matrix projection = Matrix.CreatePerspectiveFieldOfView(
                    MathHelper.PiOver4,
                    (float)this.GraphicsDevice.Viewport.Width /
                        (float)this.GraphicsDevice.Viewport.Height,
                    1.0f,
                    100.0f
                );

            ///// ボックスモデル /////

            foreach (ModelMesh mesh in this.box.Meshes)
            {
                foreach (BasicEffect effect in mesh.Effects)
                {
                    // ライトの設定
                    effect.EnableDefaultLighting();

                    // ボックスの位置をカメラの注視点に合わせる
                    effect.World = Matrix.CreateTranslation(this.cameraTarget);

                    // ビューマトリックスを設定
                    effect.View = view;

                    // プロジェクションマトリックス設定
                    effect.Projection = projection;
                }

                mesh.Draw();
            }

            ///// XYZ軸モデル /////

            foreach (ModelMesh mesh in this.xyz.Meshes)
            {
                foreach (BasicEffect effect in mesh.Effects)
                {
                    // ライトの設定
                    effect.EnableDefaultLighting();

                    // 原点に配置
                    effect.World = Matrix.Identity;

                    // ビューマトリックスを設定
                    effect.View = view;

                    // プロジェクションマトリックス設定
                    effect.Projection = projection;
                }

                mesh.Draw();
            }

            // スプライトの描画準備
            this.spriteBatch.Begin();

            // カメラの情報を表示
            this.spriteBatch.DrawString(this.font,
                "CameraPosition : {" +
                    this.cameraPosition.X.ToString("f2") + ", " +
                    this.cameraPosition.Y.ToString("f2") + "}" + Environment.NewLine +
                "CameraTarget : {" +
                    this.cameraTarget.X.ToString("f2") + ", " +
                    this.cameraTarget.Y.ToString("f2") + "}" + Environment.NewLine +
                "CameraUpVectorRotate : " + this.cameraUpVectorRotate.ToString("f2") + Environment.NewLine +
                "MousePressAutoMode : " + this.autoMode,
                new Vector2(20, 20), Color.White);

            // スプライトの一括描画
            this.spriteBatch.End();

            // 登録された DrawableGameComponent を描画する
            base.Draw(gameTime);
        }
    }
}