Dibujando un cubo con textura con lados múltiples en XNA 4.0

Question

He estado golpeando mi cabeza contra este problema durante horas. Lo que quiero hacer es dibujar un cubo, con diferentes texturas en cada lado; o más específicamente, quiero poder especificar cualquier textura que quiera por cada lado. Para empezar, utilicé el ejemplo here y luego intenté desarrollarlo más, para poder tener más de una textura. Sin embargo, no importa lo que haga, solo utiliza la última textura que se aplica al efecto y no presta atención a ninguna asignación anterior. Aquí está mi clase de forma:

public class BasicShape { 

public Vector3 shapeSize; 
public Vector3 shapePosition; 
private VertexPositionNormalTexture[][] shapeVertices; 
private int shapeTriangles; 
private VertexBuffer shapeBuffer; 
public Texture2D topTexture; 
public Texture2D frontTexture; 
public Texture2D backTexture; 
public Texture2D leftTexture; 
public Texture2D rightTexture; 
public Texture2D bottomTexture; 

public BasicShape(Vector3 size, Vector3 position) { 
    shapeSize = size; 
    shapePosition = position; 
} 

private void BuildShape() { 
    shapeTriangles = 12; 

    shapeVertices = new VertexPositionNormalTexture[6][]; 
    for(int i = 0; i < 6; i++) { 
     shapeVertices[i] = new VertexPositionNormalTexture[6]; 
    } 

    Vector3 topLeftFront = shapePosition + 
    new Vector3(0.0f, 1.0f, 0.0f) * shapeSize; 
    Vector3 bottomLeftFront = shapePosition + 
    new Vector3(0.0f, 0.0f, 0.0f) * shapeSize; 
    Vector3 topRightFront = shapePosition + 
    new Vector3(1.0f, 1.0f, 0.0f) * shapeSize; 
    Vector3 bottomRightFront = shapePosition + 
    new Vector3(1.0f, 0.0f, 0.0f) * shapeSize; 
    Vector3 topLeftBack = shapePosition + 
    new Vector3(0.0f, 1.0f, 1.0f) * shapeSize; 
    Vector3 topRightBack = shapePosition + 
    new Vector3(1.0f, 1.0f, 1.0f) * shapeSize; 
    Vector3 bottomLeftBack = shapePosition + 
    new Vector3(0.0f, 0.0f, 1.0f) * shapeSize; 
    Vector3 bottomRightBack = shapePosition + 
    new Vector3(1.0f, 0.0f, 1.0f) * shapeSize; 

    Vector3 topLeftFront2 = shapePosition + 
    new Vector3(0.0f, 1.0f, 0.0f) * shapeSize; 
    Vector3 bottomLeftFront2 = shapePosition + 
    new Vector3(0.0f, 0.0f, 0.0f) * shapeSize; 
    Vector3 topRightFront2 = shapePosition + 
    new Vector3(1.0f, 1.0f, 0.0f) * shapeSize; 
    Vector3 bottomRightFront2 = shapePosition + 
    new Vector3(1.0f, 0.0f, 0.0f) * shapeSize; 
    Vector3 topLeftBack2 = shapePosition + 
    new Vector3(0.0f, 1.0f, 1.0f) * shapeSize; 
    Vector3 topRightBack2 = shapePosition + 
    new Vector3(1.0f, 1.0f, 1.0f) * shapeSize; 
    Vector3 bottomLeftBack2 = shapePosition + 
    new Vector3(0.0f, 0.0f, 1.0f) * shapeSize; 
    Vector3 bottomRightBack2 = shapePosition + 
    new Vector3(1.0f, 0.0f, 1.0f) * shapeSize; 

    Vector3 topLeftFront3 = shapePosition + 
    new Vector3(0.0f, 1.0f, 0.0f) * shapeSize; 
    Vector3 bottomLeftFront3 = shapePosition + 
    new Vector3(0.0f, 0.0f, 0.0f) * shapeSize; 
    Vector3 topRightFront3 = shapePosition + 
    new Vector3(1.0f, 1.0f, 0.0f) * shapeSize; 
    Vector3 bottomRightFront3 = shapePosition + 
    new Vector3(1.0f, 0.0f, 0.0f) * shapeSize; 
    Vector3 topLeftBack3 = shapePosition + 
    new Vector3(0.0f, 1.0f, 1.0f) * shapeSize; 
    Vector3 topRightBack3 = shapePosition + 
    new Vector3(1.0f, 1.0f, 1.0f) * shapeSize; 
    Vector3 bottomLeftBack3 = shapePosition + 
    new Vector3(0.0f, 0.0f, 1.0f) * shapeSize; 
    Vector3 bottomRightBack3 = shapePosition + 
    new Vector3(1.0f, 0.0f, 1.0f) * shapeSize; 

    Vector3 frontNormal = new Vector3(0.0f, 0.0f, 1.0f) * shapeSize; 
    Vector3 backNormal = new Vector3(0.0f, 0.0f, -1.0f) * shapeSize; 
    Vector3 topNormal = new Vector3(0.0f, 1.0f, 0.0f) * shapeSize; 
    Vector3 bottomNormal = new Vector3(0.0f, -1.0f, 0.0f) * shapeSize; 
    Vector3 leftNormal = new Vector3(-1.0f, 0.0f, 0.0f) * shapeSize; 
    Vector3 rightNormal = new Vector3(1.0f, 0.0f, 0.0f) * shapeSize; 

    Vector2 textureTopLeft = new Vector2(1f * shapeSize.X, 0.0f * shapeSize.Y); 
    Vector2 textureTopRight = new Vector2(0.0f * shapeSize.X, 0.0f * shapeSize.Y); 
    Vector2 textureBottomLeft = new Vector2(1f * shapeSize.X, 1f * shapeSize.Y); 
    Vector2 textureBottomRight = new Vector2(0.0f * shapeSize.X, 1f * shapeSize.Y); 

    // Front face. 
    shapeVertices[0][0] = new VertexPositionNormalTexture(
    topLeftFront, frontNormal, textureTopLeft); 
    shapeVertices[0][1] = new VertexPositionNormalTexture(
    bottomLeftFront, frontNormal, textureBottomLeft); 
    shapeVertices[0][2] = new VertexPositionNormalTexture(
    topRightFront, frontNormal, textureTopRight); 
    shapeVertices[0][3] = new VertexPositionNormalTexture(
    bottomLeftFront, frontNormal, textureBottomLeft); 
    shapeVertices[0][4] = new VertexPositionNormalTexture(
    bottomRightFront, frontNormal, textureBottomRight); 
    shapeVertices[0][5] = new VertexPositionNormalTexture(
    topRightFront, frontNormal, textureTopRight); 

    // Back face. 
    shapeVertices[1][0] = new VertexPositionNormalTexture(
    topLeftBack, backNormal, textureTopRight); 
    shapeVertices[1][1] = new VertexPositionNormalTexture(
    topRightBack, backNormal, textureTopLeft); 
    shapeVertices[1][2] = new VertexPositionNormalTexture(
    bottomLeftBack, backNormal, textureBottomRight); 
    shapeVertices[1][3] = new VertexPositionNormalTexture(
    bottomLeftBack, backNormal, textureBottomRight); 
    shapeVertices[1][4] = new VertexPositionNormalTexture(
    topRightBack, backNormal, textureTopLeft); 
    shapeVertices[1][5] = new VertexPositionNormalTexture(
    bottomRightBack, backNormal, textureBottomLeft); 

    // Top face. 
    shapeVertices[2][0] = new VertexPositionNormalTexture(
    topLeftFront2, topNormal, textureBottomLeft); 
    shapeVertices[2][1] = new VertexPositionNormalTexture(
    topRightBack2, topNormal, textureTopRight); 
    shapeVertices[2][2] = new VertexPositionNormalTexture(
    topLeftBack2, topNormal, textureTopLeft); 
    shapeVertices[2][3] = new VertexPositionNormalTexture(
    topLeftFront2, topNormal, textureBottomLeft); 
    shapeVertices[2][4] = new VertexPositionNormalTexture(
    topRightFront2, topNormal, textureBottomRight); 
    shapeVertices[2][5] = new VertexPositionNormalTexture(
    topRightBack2, topNormal, textureTopRight); 

    // Bottom face. 
    shapeVertices[3][0] = new VertexPositionNormalTexture(
    bottomLeftFront2, bottomNormal, textureTopLeft); 
    shapeVertices[3][1] = new VertexPositionNormalTexture(
    bottomLeftBack2, bottomNormal, textureBottomLeft); 
    shapeVertices[3][2] = new VertexPositionNormalTexture(
    bottomRightBack2, bottomNormal, textureBottomRight); 
    shapeVertices[3][3] = new VertexPositionNormalTexture(
    bottomLeftFront2, bottomNormal, textureTopLeft); 
    shapeVertices[3][4] = new VertexPositionNormalTexture(
    bottomRightBack2, bottomNormal, textureBottomRight); 
    shapeVertices[3][5] = new VertexPositionNormalTexture(
    bottomRightFront2, bottomNormal, textureTopRight); 

    // Left face. 
    shapeVertices[4][0] = new VertexPositionNormalTexture(
    topLeftFront3, leftNormal, textureTopRight); 
    shapeVertices[4][1] = new VertexPositionNormalTexture(
    bottomLeftBack3, leftNormal, textureBottomLeft); 
    shapeVertices[4][2] = new VertexPositionNormalTexture(
    bottomLeftFront3, leftNormal, textureBottomRight); 
    shapeVertices[4][3] = new VertexPositionNormalTexture(
    topLeftBack3, leftNormal, textureTopLeft); 
    shapeVertices[4][4] = new VertexPositionNormalTexture(
    bottomLeftBack3, leftNormal, textureBottomLeft); 
    shapeVertices[4][5] = new VertexPositionNormalTexture(
    topLeftFront3, leftNormal, textureTopRight); 

    // Right face. 
    shapeVertices[5][0] = new VertexPositionNormalTexture(
    topRightFront3, rightNormal, textureTopLeft); 
    shapeVertices[5][1] = new VertexPositionNormalTexture(
    bottomRightFront3, rightNormal, textureBottomLeft); 
    shapeVertices[5][2] = new VertexPositionNormalTexture(
    bottomRightBack3, rightNormal, textureBottomRight); 
    shapeVertices[5][3] = new VertexPositionNormalTexture(
    topRightBack3, rightNormal, textureTopRight); 
    shapeVertices[5][4] = new VertexPositionNormalTexture(
    topRightFront3, rightNormal, textureTopLeft); 
    shapeVertices[5][5] = new VertexPositionNormalTexture(
    bottomRightBack3, rightNormal, textureBottomRight); 
} 

public void SetTopTexture(Texture2D tex) { 
    topTexture = tex; 
} 
public void SetSideTexture(Texture2D tex) { 
    frontTexture = tex; 
    backTexture = tex; 
    leftTexture = tex; 
    rightTexture = tex; 
} 
public void SetBottomTexture(Texture2D tex) { 
    bottomTexture = tex; 
} 

public void RenderShape(GraphicsDevice device, Effect effect) { 
    BuildShape(); 


    effect.Parameters["xTexture"].SetValue(topTexture); 
    device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[2], 0, 2); 
    effect.Parameters["xTexture"].SetValue(bottomTexture); 
    device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[3], 0, 2); 
    effect.Parameters["xTexture"].SetValue(frontTexture); 
    device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[0], 0, 2); 
    effect.Parameters["xTexture"].SetValue(backTexture); 
    device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[1], 0, 2); 
    effect.Parameters["xTexture"].SetValue(leftTexture); 
    device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[4], 0, 2); 
    effect.Parameters["xTexture"].SetValue(rightTexture); 
    device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[5], 0, 2); 

} 

}

Y en el método de sorteo de mi juego:

cubeEffect.CurrentTechnique = cubeEffect.Techniques["Textured"]; 
    foreach(EffectPass pass in cubeEffect.CurrentTechnique.Passes) { 
     pass.Apply(); 
     BasicShape s = new BasicShape(new Vector3(1, 1, 1), new Vector3(0, 0, 3)); 
     s.SetTopTexture(TextureLoader.GetTexture(4)); 
     s.SetSideTexture(TextureLoader.GetTexture(35)); 
     s.SetBottomTexture(TextureLoader.GetTexture(4)); 
     s.RenderShape(GraphicsDevice, cubeEffect); 

    } 

Como se puede ver, yo estoy cargando diferentes texturas, sin embargo, el resultado es este :

my cube http://www.tinyimg.org/images/769MinecraftClassic_2011_.bmp

estoy seguro de que las texturas son diferentes, sin embargo, la misma textura se dibuja en todos los lados. ¿Necesito un efecto separado para cada lado? Eso definitivamente parece excesivo.

Answer 1

Cualquier parámetro establecido en el efecto no se aplica hasta que llame a EffectPass.Apply(). Esto se debe a que la aplicación de cambios a un efecto es costosa y es posible que desee realizar varios cambios de una vez.

Su función RenderShape debería ser algo como:

public void RenderShape(GraphicsDevice device, Effect effect) 
{ 
    BuildShape(); 

    foreach (EffectPass pass in effect.CurrentTechnique.Passes) 
    { 
     effect.Parameters["xTexture"].SetValue(topTexture); 
     pass.Apply(); 
     device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[2], 0, 2); 

     effect.Parameters["xTexture"].SetValue(bottomTexture); 
     pass.Apply(); 
     device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[3], 0, 2); 

     effect.Parameters["xTexture"].SetValue(frontTexture); 
     pass.Apply(); 
     device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[0], 0, 2); 

     effect.Parameters["xTexture"].SetValue(backTexture); 
     pass.Apply(); 
     device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[1], 0, 2); 

     effect.Parameters["xTexture"].SetValue(leftTexture); 
     pass.Apply(); 
     device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[4], 0, 2); 

     effect.Parameters["xTexture"].SetValue(rightTexture); 
     pass.Apply(); 
     device.DrawUserPrimitives(PrimitiveType.TriangleList, shapeVertices[5], 0, 2); 
    } 
}