UWP Composition API:圆角? [英] UWP Composition API: Rounded Corners?

问题描述

我正在努力想办法使用 Composition API 创建圆角的内容.这就是我所在的位置，任何帮助将不胜感激:

I'm struggling to figure out to to create rounded corners of content using Composition API. This is where I'm at, any help would be much appreciated:

void CreateRoundedCorners(Vector2 cornerRadius, CompositionSurfaceBrush imageSourceBrush, SpriteVisual targetVisual)
{
    CompositionRoundedRectangleGeometry roundedRectangle = _compositor.CreateRoundedRectangleGeometry();
    roundedRectangle.Size = new Vector2(;
    roundedRectangle.CornerRadius = cornerRadius;

    CompositionSpriteShape spriteShape = _compositor.CreateSpriteShape(roundedRectangle);
    spriteShape.FillBrush = _compositor.CreateColorBrush(Colors.Black);
    spriteShape.CenterPoint = new Vector2(_imageSize.X / 2, _imageSize.Y / 2);

    ShapeVisual spriteShapeVisual = _compositor.CreateShapeVisual();
    spriteShapeVisual.Size = _imageSize;
    spriteShapeVisual.Shapes.Add(spriteShape);

    CompositionMaskBrush maskBrush = _compositor.CreateMaskBrush();
    maskBrush.Source = imageSourceBrush;
    maskBrush.Mask = null; // How do I get the rectangle shape in here?

    targetVisual.Brush = maskBrush;
}

推荐答案

我想出了一个解决方案.创建一个 CompositionVisualSurface，向其中添加 ShapeVisual，并从中创建一个 CompositionSurfaceBrush 用作遮罩源.

I have figured out a solution. Creating a CompositionVisualSurface, adding the ShapeVisual to it, and creating a CompositionSurfaceBrush from that to use as the Mask source.

void CreateRoundedCorners(Vector2 cornerRadius, CompositionBrush imageSourceBrush, SpriteVisual targetVisual)
{
    CompositionRoundedRectangleGeometry roundedRectangle =_compositor.CreateRoundedRectangleGeometry();
    roundedRectangle.Size = _imageSize;
    roundedRectangle.CornerRadius = cornerRadius;

    CompositionSpriteShape spriteShape = _compositor.CreateSpriteShape(roundedRectangle);
    spriteShape.FillBrush = _compositor.CreateColorBrush(Colors.Black);
    spriteShape.CenterPoint = new Vector2(_imageSize.X / 2, _imageSize.Y / 2);

    ShapeVisual spriteShapeVisual = _compositor.CreateShapeVisual();
    spriteShapeVisual.BorderMode = CompositionBorderMode.Soft;
    spriteShapeVisual.Size = _imageSize;
    spriteShapeVisual.Shapes.Add(spriteShape);

    CompositionVisualSurface surface = _compositor.CreateVisualSurface();
    surface.SourceSize = _imageSize;
    surface.SourceVisual = spriteShapeVisual;

    CompositionMaskBrush maskBrush = _compositor.CreateMaskBrush();
    maskBrush.Source = imageSourceBrush;
    maskBrush.Mask = _compositor.CreateSurfaceBrush(surface);

    targetVisual.Brush = maskBrush;
}

也可以从 Shape 中获取蒙版，但前提是它已经在可视化树中:

A mask can also be obtained from a Shape but only if it's already in the visual tree:

Windows.UI.Xaml.Shapes.Shape rect = new Rectangle();
CompositionBrush mask = rect.GetAlphaMask();

这篇关于UWP Composition API:圆角?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！