Path2D

NOTE

This component is supported since API version 4. Updates will be marked with a superscript to indicate their earliest API version.

Path2D allows you to describe a path through an existing path. This path can be drawn through the stroke API of Canvas.

addPath

addPath(path: Object): void

Adds a path to this path.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 500px; height: 500px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path1 = ctx.createPath2D("M250 150 L150 350 L350 350 Z");
    var path2 = ctx.createPath2D();
    path2.addPath(path1);
    ctx.stroke(path2);
  }
}

setTransform

setTransform(scaleX: number, skewX: number, skewY: number, scaleY: number, translateX: number, translateY: number): void

Sets the path transformation matrix.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 300px; height: 250px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path = ctx.createPath2D("M250 150 L150 350 L350 350 Z");
    path.setTransform(0.8, 0, 0, 0.4, 0, 0);
    ctx.stroke(path);
  }
}

closePath

closePath(): void

Moves the current point of the path back to the start point of the path, and draws a straight line between the current point and the start point. If the shape is closed or has only one point, this method does not perform any action.

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 500px; height: 500px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path = ctx.createPath2D();
    path.moveTo(200, 100);
    path.lineTo(300, 100);
    path.lineTo(200, 200);
    path.closePath();
    ctx.stroke(path);
  }
}

moveTo

moveTo(x: number, y: number): void

Moves the current coordinate point of the path to the target point, without drawing a line during the movement.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 300px; height: 250px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path = ctx.createPath2D();
    path.moveTo(50, 100);
    path.lineTo(250, 100);
    path.lineTo(150, 200);
    path.closePath();
    ctx.stroke(path);
  }
}

lineTo

lineTo(x: number, y: number): void

Draws a straight line from the current point to the target point.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 400px; height: 450px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path = ctx.createPath2D();
    path.moveTo(100, 100);
    path.lineTo(100, 200);
    path.lineTo(200, 200);
    path.lineTo(200, 100);
    path.closePath();
    ctx.stroke(path);
  }
}

bezierCurveTo

bezierCurveTo(cp1x: number, cp1y: number, cp2x: number, cp2y: number, x: number, y: number): void

Draws a cubic bezier curve on the canvas.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 300px; height: 250px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path = ctx.createPath2D();
    path.moveTo(10, 10);
    path.bezierCurveTo(20, 100, 200, 100, 200, 20);
    ctx.stroke(path);
  }
}

quadraticCurveTo

quadraticCurveTo(cpx: number, cpy: number, x: number, y: number): void

Draws a quadratic curve on the canvas.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 300px; height: 250px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path = ctx.createPath2D();
    path.moveTo(10, 10);
    path.quadraticCurveTo(100, 100, 200, 20);
    ctx.stroke(path);
  }
}

arc

arc(x: number, y: number, radius: number, startAngle: number, endAngle: number, anticlockwise: number): void

Draws an arc on the canvas.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 300px; height: 250px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path = ctx.createPath2D();
    path.arc(100, 75, 50, 0, 6.28);
    ctx.stroke(path);
  }
}

arcTo

arcTo(x1: number, y1: number, x2: number, y2: number, radius: number): void

Draws an arc based on the radius and points on the arc.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 300px; height: 250px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path = ctx.createPath2D();
    path.arcTo(150, 20, 150, 70, 50);
    ctx.stroke(path);
  }
}

ellipse

ellipse(x: number, y: number, radiusX: number, radiusY: number, rotation: number, startAngle: number, endAngle: number, anticlockwise: number): void

Draws an ellipse in the specified rectangular region.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 500px; height: 450px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx =el.getContext('2d');
    var path = ctx.createPath2D();
    path.ellipse(200, 200, 50, 100, Math.PI * 0.25, Math.PI * 0.5, Math.PI, 1);
    ctx.stroke(path);
  }
}

rect

rect(x: number, y: number, width: number, height: number): void

Creates a rectangle.

Parameters

Example

<!-- xxx.hml -->
<div>
  <canvas ref="canvas" style="width: 500px; height: 450px; background-color: #ffff00;"></canvas>
</div>

// xxx.js
export default {
  onShow() {
    const el =this.$refs.canvas;
    const ctx = el.getContext('2d');
    var path = ctx.createPath2D();
    path.rect(20, 20, 100, 100);
    ctx.stroke(path);
  }
}

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