为什么我的三角形是白色的？

Question

我正在尝试绘制一个绿色三角形。我设法绘制了三角形，但它是白色而不是绿色。有谁知道是什么原因造成的？

这是我的代码：

protected override void LoadContent()
    {
        _vertexPositionColors = new[]
{
    new VertexPositionColor(new Vector3(0, 0, 0), Color.Green),
    new VertexPositionColor(new Vector3(100, 0, 0), Color.Red),
    new VertexPositionColor(new Vector3(100, 100, 0), Color.Blue)
};
        _basicEffect = new BasicEffect(GraphicsDevice);
        _basicEffect.World = Matrix.CreateOrthographicOffCenter(
            0, GraphicsDevice.Viewport.Width, GraphicsDevice.Viewport.Height, 0, 0, 1);
        _basicEffect.LightingEnabled = false;
        _basicEffect.VertexColorEnabled = true;
    }

protected override void Draw(GameTime gameTime)
    {
        GraphicsDevice.Clear(Color.CornflowerBlue);

        EffectTechnique effectTechnique = _basicEffect.Techniques[0];
        EffectPassCollection effectPassCollection = effectTechnique.Passes;
        foreach (EffectPass pass in effectPassCollection)
        {
            pass.Apply();
            GraphicsDevice.DrawUserPrimitives(PrimitiveType.TriangleList, _vertexPositionColors, 0, 1);
        }
        base.Draw(gameTime);
    }

Answer 1

问题出在你的Draw上。当您只需要应用当前技术时，您正在应用所有技术。执行以下操作对我有用：

protected override void Draw(GameTime gameTime)
{
    GraphicsDevice.Clear(Color.CornflowerBlue);
    _basicEffect.CurrentTechnique.Passes[0].Apply();
    GraphicsDevice.DrawUserPrimitives(PrimitiveType.TriangleList, _vertexPositionColors, 0, 1);
    base.Draw(gameTime);
}

为什么我的三角形是白色的？

Why is my triangle white?

c#

xna

2d

monogame