One tip if you do go down this route: Expression Blend has good support for applying Clipping Paths to elements. So this technique might work quite well in code, but not so straightforwardly in XAML, unless you have simple, static shapes. If the element changes in size, the geometry has to be updated too – and WPF won’t do that automatically. The thing that makes this not quite so easy to use as the ClipToBounds method is that the geometry in the Clip property has to match exactly the shape of the element you’re applying it to. To get the background fill, I put another copy of the shape behind (using a Grid to layer the two) and set its Fill to the colour I want. Here’s a rectangle with an inner shadow on just its top edge:Īs you can see, I’m using the same trick of applying the DropShadowEffect to a shape with a solid border but transparent fill, then clipping off the outer shadow, this time by setting a Clip region on the same shape. Want shadows on just a couple of edges? That’s easy: just turn off the appropriate lines on the inner Border using its BorderThickness property. For example, a BorderThickness of 10 (and a Margin of –12 to compensate) gives you:
This lets you vary the density of the inner shadow. I use negative margins on the inner border to push out its edge so that it gets clipped by the Clip region of the outer border, effectively hiding it.Īnother thing you can experiment with is changing the thickness of the inner border.This is what clips off the outer part of the drop shadow. The critical part that makes this shadow an inner, and not an all-round, shadow: the Border with the DropShadowEffect is nested inside another border which has ClipToBounds="True".There’s the Color property to experiment with too. Fiddle with DropShadowEffect’s BlurRadius and Opacity properties if you want to vary the lightness of the shadow. This also ensures that the shadow is even in all directions. The DropShadowEffect has its ShadowDepth set to 0 so that there’s no gap between the border and the start of the shadow.This produces a shadow effect on both sides of the border. I apply the DropShadowEffect to an element (a Border in this case) that has a solid border, but transparent fill.Here’s how I created the inner shadow shown above: This is the easiest way of using Clip regions because you don’t have to think about their geometry or worry about resizing if the element changes size: WPF uses the natural bounding-rectangle of the element as the Clip region. Set this to true, and WPF will make sure that no part of an element or its children will spill outside of its borders. I’ll start with the simplest technique for drawing Inner Shadows: applying Clip regions using the ClipToBounds property. If the pixel in the Opacity Mask is opaque, or semi-opaque, then WPF renders that pixel of your element. If the pixel in the Opacity Mask is transparent, then WPF ignores the corresponding pixel of your element. Each pixel in your element is given the same opacity as the corresponding pixel in the Opacity Mask. Opacity Masks are like stencils which WPF lays over the top of your element. They tell WPF, thus far shalt thou render, and no further.
Everything inside the geometry is rendered, everything outside ignored. Clip regions are geometries – rectangles, ellipses, or arbitrary paths, which specify the boundaries of a shape.
They instruct WPF to trim off, or hide, certain parts of a visual when rendering it to the screen. DropShadowEffect can be used to create an inner shadow, using one of two nifty WPF features: Clip regions and Opacity Masks.Ĭlip regions and Opacity Masks both achieve a similar effect, though in different ways. Question is, how can we create an inner shadow in WPF? Look in the namespace, and you’ll find the DropShadowEffect class, but no InnerShadowEffect. Subtle, isn’t it? But it adds a touch of realism to the rendering. If you've not met an inner shadow before, allow me to introduce you.Īnd here's a grey rectangle with an inner shadow: In this article, I'll show you a couple of ways of creating inner shadow effects in WPF, one of which also works for Silverlight. So you'll know that whilst it does a pretty good job of importing simple Photoshop files, it struggles when asked to convert the little flourishes with which designers like to top off their masterpieces. If you've ever been tasked with converting a Photoshop design into a WPF UI, you'll probably have tried the Expression Blend Photoshop Import feature.
0 kommentar(er)
