Colors, styles and shadows Properties Describe fillStyle Set/return the color, gradient or pattern used to fill the drawing strokeStyle Set/return the color, gradient or pattern used for the strokes shadowColor Set/return the color to use for the drop shadow shadowBlur Set/return opacity level for shadow shadowOffsetX Set/return horizontal distance of shadow from shape shadowOffsetY Set/return the vertical distance of the shadow from the shape
Method Describe createLinearGradient() Create a linear gradient (for use on canvas content) createPattern() Iterate over a specified element in the specified direction createRadialGradient() Create a radial/circular gradient (for use on canvas content) addColorStop() Specify color and stop position in a gradient object
Line style Properties Describe lineCap Set/return the style of the bullets for a line lineJoin Set/return the type of angle generated, when two lines meet lineWidth Set/return current line width miterLimit Set/return the maximum miter length
Rectangle Method Describe rect() Create a rectangle fillRect() Draw a rectangle "with fill" strokeRect() Draw a rectangle (no fill) clearRect() Remove specified pixels within a given rectangle
Calibration curve Method Describe fill() Fill in the current drawing (standard line) stroke() Draw the standard curve you have determined in practice beginPath() Start a calibration curve or reset the current calibration curve moveTo() Move the reference line to the specified point in the canvas without creating the line closePath() Create a reference line from the current point back to the starting point lineTo() Add a new point and create a line to it from the last specified point in the canvas clip() Crop an area of any shape and size from the original canvas quadraticCurveTo() Creating quadratic Bézier curves bezierCurveTo() Creating a cubic Bézier curve arc() Create an arc/curve (used to create circles or sections of circles) arcTo() Create an arc/curve between two tangents isPointInPath() Returns true if the specified point is within the current calibration curve, false otherwise
Change Method Describe scale() Scale the current drawing larger or smaller rotate() Rotate current drawing translate() Fix position (0,0) on canvas transform() Substitute the current transformation matrix for the drawing setTransform() Reset transforms the current into an identity matrix. Then run transform()
Document Properties Describe font Set/return current font properties for body text textAlign Set/return current alignment of body text textBaseline Set/return the current text baseline used when drawing text
Method Describe fillText() Draw the word "with color" on the canvas strokeText() Draw text on canvas (no fill color) measureText() Returns an object containing the specified text width
Draw pictures Method Describe drawImage() Draw an image, canvas or video onto the canvas
Pixel manipulation Properties Describe width Returns the width of the ImageData . object Cao Returns the height of the ImageData . object data Returns an object containing the image data of the specified ImageData object
Method Describe createImageData() Create a new, empty ImageData object getImageData() Returns an ImageData object that copies the pixel data for the specified rectangle on the canvas putImageData() Set image data (from a specified ImageData object) back to canvas
Compositing Properties Describe globalAlpha Set/return the current alpha or transparency value of the drawing globalCompositeOperation Set/return how a new image is drawn over an existing image
Other Method Describe save() Save the state of the current context restore() Returns the state and properties of the previously saved calibration curve createEvent() getContext() toDataURL()
Marvin Fry Update 10 May 2022