Shapes and Brushes

WPF ships a small family of Shape classes — Rectangle, Ellipse, Line, Polyline, Polygon, and Path — that render vector graphics directly inside the visual tree, unlike bitmap-based drawing in WinForms GDI+. Because a Shape derives from FrameworkElement, it participates fully in layout, data binding, styling, and animation, so a Rectangle can be resized by its parent Grid, bound to a ViewModel property, and animated exactly like a Button. A Brush, separately, is the object that actually paints a region: shapes use Fill for their interior and Stroke for their outline, and both properties accept any Brush subtype.

All shapes derive from the abstract Shape class, which exposes Fill, Stroke, StrokeThickness, StrokeDashArray, and StrokeLineJoin. Rectangle and Ellipse take Width/Height plus optional RadiusX/RadiusY for rounded corners; Line takes X1/Y1/X2/Y2 coordinates; Polygon and Polyline take a Points collection, with Polygon automatically closing the last point back to the first. Path is the most powerful member because its Data property accepts any Geometry object — including combinations of geometries via GeometryGroup or CombinedGeometry — so a Path can render arbitrary curves, arcs, and Bezier segments that the simpler shapes cannot express.

SolidColorBrush paints a single flat Color and is the default for most Fill and Stroke assignments. LinearGradientBrush interpolates colors along a StartPoint/EndPoint axis defined in relative (0-1) or absolute coordinates using GradientStop children, while RadialGradientBrush interpolates outward from a center and focus point, useful for glow or spotlight effects. ImageBrush stretches or tiles a bitmap into the fill region using Stretch and TileMode, and VisualBrush is the most flexible of all because it paints with a live snapshot of any WPF Visual — including another control — which is how WPF implements effects like reflections and magnifiers.

ImageBrush and VisualBrush both consume a Viewport and Viewbox pair that control how their source content is scaled and tiled into the target region, and TileMode set to Tile or FlipXY produces repeating pattern fills such as a checkerboard or wallpaper texture. VisualBrush is commonly used to create a live reflection under a control by rendering a ScaleTransform-flipped copy of the source Visual with decreasing Opacity, and it is also the backbone of WPF's magnifier and thumbnail preview scenarios because the brush re-renders whenever its source Visual changes.

The Data property of a Path accepts either a Geometry object graph (LineGeometry, RectangleGeometry, EllipseGeometry, PathGeometry) or a compact mini-language string like "M 20,150 C 60,100 140,200 180,150" where M moves the pen, L draws a line, C draws a cubic Bezier, and Z closes the figure. PathGeometry offers a rich object model with PathFigure and PathSegment collections that supports data binding and animation of individual points, whereas StreamGeometry is a lighter, write-once, non-bindable alternative built with a StreamGeometryContext that renders faster and consumes less memory for static, complex artwork such as icon sets.