Matrices can be used to represent transformations of objects in space, and are an important tool to use in visualizations on the Web. This article explores how to create matrices and use them with CSS3 transforms and the matrix3d transform type.
The CanvasRenderingContext2D.addHitRegion() method of the Canvas 2D API adds a hit region to the bitmap. This allows you to make hit detection easier, lets you route events to DOM elements, and makes it possible for users to explore the canvas without seeing it.
The CanvasRenderingContext2D.arc() method of the Canvas 2D API adds an arc to the path which is centered at (x, y) position with radius r starting at startAngle and ending at endAngle going in the given direction by anticlockwise (defaulting to clockwise).
The CanvasRenderingContext2D.bezierCurveTo() method of the Canvas 2D API adds a cubic Bézier curve to the path. It requires three points. The first two points are control points and the third one is the end point. The starting point is the last point in the current path, which can be changed using moveTo() before creating the Bézier curve.
The CanvasRenderingContext2D.canvas property is a read-only reference to the HTMLCanvasElement object that is associated with the context. It might be null if there is no association with an <canvas> element.
The CanvasRenderingContext2D.clearRect() method of the Canvas 2D API sets all pixels in the rectangle defined by starting point (x, y) and size (width, height) to transparent black, erasing any previously drawn content.
The CanvasRenderingContext2D.closePath() method of the Canvas 2D API causes the point of the pen to move back to the start of the current sub-path. It tries to add a straight line (but does not actually draw it) from the current point to the start. If the shape has already been closed or has only one point, this function does nothing.
The CanvasRenderingContext2D.createImageData() method of the Canvas 2D API creates a new, blank ImageData object with the specified dimensions. All of the pixels in the new object are transparent black.
The CanvasRenderingContext2D.createLinearGradient() method of the Canvas 2D API creates a gradient along the line given by the coordinates represented by the parameters. This method returns a linear CanvasGradient.
The CanvasRenderingContext2D.createPattern() method of the Canvas 2D API creates a pattern using the specified image (a CanvasImageSource). It repeats the source in the directions specified by the repetition argument. This method returns a CanvasPattern.
The CanvasRenderingContext2D.createRadialGradient() method of the Canvas 2D API creates a radial gradient given by the coordinates of the two circles represented by the parameters. This method returns a CanvasGradient.