ICanvas4

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Interface ICanvas4

interface ICanvas4

Extends ICanvas3 ICanvas4 interface extends ICanvas3 with primitives for drawing the shadows of Rect and RRect occluders, following CSS box-shadow semantics.

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Methods

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drawShadowRect()

void drawShadowRect(Rect* rect, Point offset, Color color, float sigma)

Draws a box shadow cast by the given Rect. The shadow is rendered as the rect filled with the given color, offset by the given amount and Gaussian-blurred by the given sigma.

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Parameters

rect

Rect* — Required The Rect that casts the shadow.

offset

Point — Required Shadow offset. Point

color

Color — Required The color of the shadow. Color

sigma

float — Required Standard deviation of the Gaussian blur applied to the shadow. Larger values produce a softer, wider edge.

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Throws

• InvalidArgumentError — if sigma is zero or negative.

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drawShadowRRect()

void drawShadowRRect(RRect* rRect, Point offset, Color color, float sigma)

Draws a box shadow cast by the given RRect. The shadow is rendered as the rounded rect filled with the given color, offset by the given amount and Gaussian-blurred by the given sigma.

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Parameters

rRect

RRect* — Required The RRect that casts the shadow.

offset

Point — Required Shadow offset. Point

color

Color — Required The color of the shadow. Color

sigma

float — Required Standard deviation of the Gaussian blur applied to the shadow. Larger values produce a softer, wider edge.

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Throws

• InvalidArgumentError — if sigma is zero or negative.

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