VCS/XnaTexture2D2 - Sample is best!

開発環境	Microsoft Visual C# 2010 Express (SP1)
実行環境	Microsoft Windows XP Home Edition (SP3)
プロジェクトの種類	Windows Game (4.0)
プロジェクト名	XnaTexture2D

1. スクロール
2. モルワイデ風

参考

• Planet Earth Texture Maps

Game1.cs

// XnaTexture2D2 テクスチャ移動
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
 
namespace XnaTexture2D
{
    class Game1 : Game
    {
        GraphicsDeviceManager graphics;
        SpriteBatch sprite;
        SpriteFont font;
        VertexBuffer vertexBuffer;
        Effect effect;
        Texture2D texture;
 
        EffectParameter fxLat;
        EffectParameter fxLon;
        float lat = 0;
        float lon = 0;
 
        // fps
        int sec;
        int draw = 0;
        int fps = 0;
 
        public Game1()
        {
            graphics = new GraphicsDeviceManager(this);
            graphics.PreferredBackBufferWidth = 1280;
            graphics.PreferredBackBufferHeight = 720;
            Content.RootDirectory = "Content";
            IsMouseVisible = true;
        }
 
        protected override void LoadContent()
        {
            sprite = new SpriteBatch(GraphicsDevice);
            font = Content.Load<SpriteFont>("SpriteFont1");
            texture = Content.Load<Texture2D>("earthmap1k");
 
            effect = Content.Load<Effect>("Effect1");
            effect.Parameters["WorldMap"].SetValue(texture);
            fxLat = effect.Parameters["lat"];
            fxLon = effect.Parameters["lon"];
 
            VertexPositionTexture[] vertices = new VertexPositionTexture[4];
            vertices[0] = new VertexPositionTexture(new Vector3(-1, 1, 0), new Vector2(0, 0));
            vertices[1] = new VertexPositionTexture(new Vector3(1, 1, 0), new Vector2(1, 0));
            vertices[2] = new VertexPositionTexture(new Vector3(-1, -1, 0), new Vector2(0, 1));
            vertices[3] = new VertexPositionTexture(new Vector3(1, -1, 0), new Vector2(1, 1));
 
            vertexBuffer = new VertexBuffer(GraphicsDevice,
                typeof(VertexPositionTexture), 4, BufferUsage.WriteOnly);
            vertexBuffer.SetData(vertices);
 
            base.LoadContent();
        }
 
        protected override void Update(GameTime gameTime)
        {
            float deltaLat = 0;
            float deltaLon = 0;
 
            KeyboardState kState = Keyboard.GetState();
            if (kState.IsKeyDown(Keys.Escape)) Exit();
            if (kState.IsKeyDown(Keys.Up)) deltaLat = -0.005f;
            if (kState.IsKeyDown(Keys.Down)) deltaLat = 0.005f;
            if (kState.IsKeyDown(Keys.Left)) deltaLon = -0.005f;
            if (kState.IsKeyDown(Keys.Right)) deltaLon = 0.005f;
 
            if (deltaLat != 0)
            {
                lat += deltaLat;
                if (lat < -1.0f) lat += 2.0f;
                if (1.0f < lat) lat -= 2.0f;
                fxLat.SetValue(lat);
            }
            if (deltaLon != 0)
            {
                lon += deltaLon;
                fxLon.SetValue(lon);
            }
 
            base.Update(gameTime);
        }
 
        protected override void Draw(GameTime gameTime)
        {
            GraphicsDevice.Clear(Color.CornflowerBlue);
            GraphicsDevice.SamplerStates[0] = SamplerState.LinearClamp;
 
            GraphicsDevice.SetVertexBuffer(vertexBuffer);
            foreach (EffectPass pass in effect.CurrentTechnique.Passes)
            {
                pass.Apply();
                GraphicsDevice.DrawPrimitives(PrimitiveType.TriangleStrip, 0, 2);
            }
 
            // fps
            draw++;
            if (gameTime.TotalGameTime.Seconds != sec)
            {
                fps = draw;
                draw = 0;
                sec = gameTime.TotalGameTime.Seconds;
            }
 
            sprite.Begin();
            string text = string.Format("fps={0} lat={1:f2} lon={2:f2}", fps, lat, lon);
            sprite.DrawString(font, text, new Vector2(0, 0), Color.Red);
            sprite.End();
 
            base.Draw(gameTime);
        }
    }
}
 

Effect1.fx

// スクロール
texture WorldMap;
float lat;
float lon;
 
sampler TextureSampler = sampler_state
{
	texture = <WorldMap>;
	minfilter = linear;
	magfilter = linear;
};
 
struct VertexShaderInput
{
	float4 Position : POSITION0;
	float2 TexCoord : TEXCOORD0;
};
 
struct VertexShaderOutput
{
	float4 Position : POSITION0;
	float2 TexCoord : TEXCOORD0;
};
 
VertexShaderOutput VertexShaderFunction(VertexShaderInput input)
{
	VertexShaderOutput output;
	output.Position = input.Position;
	output.TexCoord = input.TexCoord;
	return output;
}
 
float4 PixelShaderFunction(VertexShaderOutput input) : COLOR0
{
	float2 t;
	t.x = frac(input.TexCoord.x + lon);
//	t.y = frac(input.TexCoord.y + lat);
	t.y = abs(input.TexCoord.y + lat);
	if (1.0f < t.y)
	{
		t.y = 2.0f - t.y;
	}
	return tex2D(TextureSampler, t);
}
 
technique Technique1
{
	pass Pass1
	{
		VertexShader = compile vs_2_0 VertexShaderFunction();
		PixelShader = compile ps_2_0 PixelShaderFunction();
	}
}
 

Effect1.fx

// モルワイデ風
texture WorldMap;
float lat; // 未使用
float lon;
 
sampler TextureSampler = sampler_state
{
	texture = <WorldMap>;
	minfilter = linear;
	magfilter = linear;
};
 
struct VertexShaderInput
{
	float4 Position : POSITION0;
	float2 TexCoord : TEXCOORD0;
};
 
struct VertexShaderOutput
{
	float4 Position : POSITION0;
	float2 TexCoord : TEXCOORD0;
};
 
VertexShaderOutput VertexShaderFunction(VertexShaderInput input)
{
	VertexShaderOutput output;
	output.Position = input.Position;
	output.TexCoord = input.TexCoord;
	return output;
}
 
float4 PixelShaderFunction(VertexShaderOutput input) : COLOR0
{
	float x = input.TexCoord.x * 2.0f - 1.0f; // -1 - 1
	float y = input.TexCoord.y * 2.0f - 1.0f; // -1 - 1
	float width = sqrt(1.0f - y * y);
	if (width < abs(x) || width == 0.0f)
	{
		discard;
	}
	float2 t;
	t.x = frac((x / width) * 0.5f + 0.5f + lon);
	t.y = input.TexCoord.y;
	return tex2D(TextureSampler, t);
}
 
technique Technique1
{
	pass Pass1
	{
		VertexShader = compile vs_2_0 VertexShaderFunction();
		PixelShader = compile ps_2_0 PixelShaderFunction();
	}
}