a:outerShdw (Outer Shadow)

Applies an outer shadow effect to shapes with configurable blur, distance, angle, and color.

Parent elements

Child elements

## Description `a:outerShdw` applies an **outer shadow effect** to a DrawingML shape. It is defined in **ECMA-376 Part 1 §20.1.8.18**. The shadow appears outside the shape outline with the following properties: - **Blur radius** – How soft/blurred the shadow edges are - **Distance** – How far the shadow extends from the shape - **Direction** – Angle at which the shadow projects (in 60,000ths of a degree) - **Alignment** – Where the shadow originates (top-left, center, bottom-right, etc.) - **Opacity/Color** – Shadow color and transparency ## Attributes | Attribute | Type | Possible Values | Description | |---|---|---|---| | `blurRad` | `ST_Coordinate32` | 0 to 2147483647 (EMUs) | Blur radius for soft shadow edges; 0 = sharp edge. | | `dist` | `ST_Coordinate32` | 0 to 2147483647 (EMUs) | Distance the shadow extends from the shape boundary. | | `dir` | `ST_PositiveFixedAngle` | 0 to 21600000 (in 60,000ths of a degree) | Direction angle; 0° = right, 2700000 = 90° down. | | `algn` | `ST_RectAlignment` | `tl`, `t`, `tr`, `l`, `ctr`, `r`, `bl`, `b`, `br` | Shadow alignment relative to the shape. | | `rotWithShape` | `xsd:boolean` | 0 \| 1 | If true, shadow rotates with the shape. | | `sx` | `ST_Percentage` | -100000 to 100000 (in 1000ths of %) | Horizontal scaling. | | `sy` | `ST_Percentage` | -100000 to 100000 (in 1000ths of %) | Vertical scaling. | | `kx` | `ST_FixedAngle` | -5400000 to 5400000 (in 60,000ths of a degree) | Horizontal skew/shear. | | `ky` | `ST_FixedAngle` | -5400000 to 5400000 (in 60,000ths of a degree) | Vertical skew/shear. | | `algn` | `ST_RectAlignment` | `tl`, `t`, `tr`, `l`, `ctr`, `r`, `bl`, `b`, `br` | Shadow position reference. | | `tau` | `ST_Percentage` | 0 to 100000 (in 1000ths of %) | Vertical offset (tau parameter). | ## Examples ### Simple Black Outer Shadow

<a:outerShdw blurRad="38100" dist="38100" dir="2700000" algn="tl" rotWithShape="0">
  <a:srgbClr val="000000">
    <a:alpha val="50000"/>
  </a:srgbClr>
</a:outerShdw>

using DocumentFormat.OpenXml.Drawing;

var shadow = new OuterShadow
{
    BlurRadius = 38100,
    Distance = 38100,
    Direction = 2700000,  // 90 degrees
    Alignment = RectangleAlignmentValues.TopLeft,
    RotateWithShape = false
};

// Add semi-transparent black color
var color = new RgbColorModelHex { Val = "000000" };
color.Append(new Alpha { Val = 50000 });  // 50% opacity
shadow.Append(color);

### Soft Blurred Shadow with Center Alignment

<a:outerShdw blurRad="76200" dist="50800" dir="5400000" algn="ctr" rotWithShape="1">
  <a:srgbClr val="4A4A4A">
    <a:alpha val="40000"/>
  </a:srgbClr>
</a:outerShdw>

var shadow = new OuterShadow
{
    BlurRadius = 76200,      // More blur
    Distance = 50800,        // Farther distance
    Direction = 5400000,     // 135 degrees (diagonal)
    Alignment = RectangleAlignmentValues.Center,
    RotateWithShape = true   // Rotate with shape
};

var color = new RgbColorModelHex { Val = "4A4A4A" };
color.Append(new Alpha { Val = 40000 });  // 40% opacity
shadow.Append(color);

### Colored Shadow with Scheme Color

<a:outerShdw blurRad="50800" dist="63500" dir="2700000" algn="bl" rotWithShape="0">
  <a:schemeClr val="accent1">
    <a:alpha val="60000"/>
  </a:schemeClr>
</a:outerShdw>

var shadow = new OuterShadow
{
    BlurRadius = 50800,
    Distance = 63500,
    Direction = 2700000,
    Alignment = RectangleAlignmentValues.BottomLeft,
    RotateWithShape = false
};

var color = new SchemeColor { Val = ColorSchemeIndexValues.Accent1 };
color.Append(new Alpha { Val = 60000 });  // 60% opacity
shadow.Append(color);

## Notes - **Blur radius** typically ranges 25400–76200 EMUs (0.03–0.08 inches) for natural-looking shadows. - **Distance** is the offset from the shape; 25400–76200 EMUs is typical. - **Direction angle**: 0° = right, 2700000 (90°) = down, 5400000 (180°) = left, 8100000 (270°) = up. - **EMU conversion**: 914400 EMUs = 1 inch; 38100 EMUs ≈ 0.042 inches. - **Shadow color** is usually dark (black or dark gray) with transparency (alpha < 100000). - **Scheme colors** can be used instead of RGB for theme-aware shadows. - The `rotWithShape` attribute controls whether the shadow rotates when the shape is rotated. ## Notes - The permitted child elements and attribute values depend on the surrounding OOXML part and the schema version in use. - In practice, DrawingML content is usually generated from higher-level shape or picture APIs rather than built manually element-by-element. - When this element appears inside a document package, it is typically linked by relationships or contained in a drawing part that is referenced from a shape or graphic object.