Table of Contents

Class ConicalGradient

Namespace
Egami.Drawing
Assembly
Egami.Drawing.dll

A gradient between two circles, as the HTML canvas's createRadialGradient, Skia's two-point conical gradient and a PDF type 3 shading define it: for each t, the circle whose center and radius are t of the way from the start circle to the end one; a pixel takes the largest t whose circle passes through it with a radius of at least 0. It covers a focal point inside a circle (a start radius of 0), one circle inside the other, and cones drawn on one side only.

public sealed record ConicalGradient : Gradient, ITextPaint, IEquatable<Paint>, IEquatable<Gradient>, IEquatable<ConicalGradient>
Inheritance
ConicalGradient
Implements
Inherited Members

Examples

using (RasterCanvas<Rgba8> canvas = raster.CreateCanvas())
{
    // Two colors along a line; past the ends the end colors repeat (TileMode.Clamp).
    canvas.FillRect(new RectF(0, 0, 200, 100), new LinearGradient(new Vector2(0, 0), new Vector2(200, 0), new RgbaF32(0.1f, 0.3f, 0.9f, 1), new RgbaF32(1, 0.8f, 0.2f, 1)));

    // Several stops, mixed in Oklab for even midpoints, repeating every 40 pixels.
    canvas.FillRect(new RectF(200, 0, 200, 100), new LinearGradient(
        new Vector2(200, 0),
        new Vector2(240, 0),
        new GradientStop(0, new Rgba8(230, 40, 60, 255)),
        new GradientStop(0.5f, new Rgba8(250, 210, 60, 255)),
        new GradientStop(1, new Rgba8(230, 40, 60, 255)))
    {
        Tile = TileMode.Repeat,
        Interpolation = GradientInterpolation.Oklab,
    });

    // A radial gradient stretched into an ellipse by its local matrix, and a sweep around a center.
    canvas.FillOval(new RectF(10, 110, 180, 80), new RadialGradient(Vector2.Zero, 1, new RgbaF32(1, 1, 1, 1), new RgbaF32(0, 0.4f, 0.2f, 1))
    {
        LocalMatrix = Matrix3x2.CreateScale(90, 40) * Matrix3x2.CreateTranslation(100, 150),
    });
    canvas.FillCircle(new Vector2(300, 150), 45, new SweepGradient(
        new Vector2(300, 150),
        new GradientStop(0, new Rgba8(255, 0, 0, 255)),
        new GradientStop(0.5f, new Rgba8(0, 0, 255, 255)),
        new GradientStop(1, new Rgba8(255, 0, 0, 255))));
}

Constructors

ConicalGradient(Vector2, float, Vector2, float, params ReadOnlySpan<GradientStop>)

Initializes a new instance of the ConicalGradient class.

public ConicalGradient(Vector2 start, float startRadius, Vector2 end, float endRadius, params ReadOnlySpan<GradientStop> stops)

Parameters

start Vector2

The start circle's center, in paint coordinates.

startRadius float

The start circle's radius, where t is 0.

end Vector2

The end circle's center.

endRadius float

The end circle's radius, where t is 1.

stops ReadOnlySpan<GradientStop>

The stops; at least one.

Exceptions

ArgumentException

A center is not finite, or there are no stops.

ArgumentOutOfRangeException

A radius is negative or not finite.

Properties

End

Gets the end circle's center.

public Vector2 End { get; init; }

Property Value

Vector2

Exceptions

ArgumentException

The point is not finite.

EndRadius

Gets the end circle's radius.

public float EndRadius { get; init; }

Property Value

float

Exceptions

ArgumentOutOfRangeException

The value is negative or not finite.

Start

Gets the start circle's center.

public Vector2 Start { get; init; }

Property Value

Vector2

Exceptions

ArgumentException

The point is not finite.

StartRadius

Gets the start circle's radius.

public float StartRadius { get; init; }

Property Value

float

Exceptions

ArgumentOutOfRangeException

The value is negative or not finite.

Edit this page