opentk在window系统渲染只显示在左下角问题

[OpenTK]

var source = PresentationSource.FromVisual(this);
if (source == null) return;

// 获取DPI缩放矩阵
Matrix m = source.CompositionTarget.TransformToDevice;
double dpiScaleX = m.M11;
double dpiScaleY = m.M22;

// 计算实际像素尺寸
double actualWidth = ActualWidth * dpiScaleX;
double actualHeight = ActualHeight * dpiScaleY;

// 设置视口 - 使用实际像素！
GL.Viewport(0, 0, (int)actualWidth, (int)actualHeight);