Documentation ¶
Index ¶
- Variables
- type Canvas
- func (el *Canvas) AppendToDocumentBody()
- func (el *Canvas) Arc(x, y, radius, startAngle, endAngle iotmaker_types.Coordinate, ...)
- func (el *Canvas) ArcTo(x1, y1, x2, y2, radius iotmaker_types.Coordinate)
- func (el *Canvas) BeginPath()
- func (el *Canvas) BezierCurveTo(cp1x, cp1y, cp2x, cp2y, x, y iotmaker_types.Coordinate)
- func (el *Canvas) Call(jsFunction string, value interface{}) js.Value
- func (el *Canvas) ClearRect(x, y, width, height iotmaker_types.Coordinate)
- func (el *Canvas) Clip(x, y iotmaker_types.Coordinate)
- func (el *Canvas) ClosePath(x, y iotmaker_types.Coordinate)
- func (el *Canvas) CreateEvent()
- func (el *Canvas) CreateImageData(data js.Value)
- func (el *Canvas) CreateLinearGradient(x0, y0, x1, y1 iotmaker_types.Coordinate)
- func (el *Canvas) CreatePattern(image js.Value, repeatRule CanvasRepeatRule)
- func (el *Canvas) CreateRadialGradient(x0, y0, r0, x1, y1, r1 iotmaker_types.Coordinate)
- func (el *Canvas) Data() js.Value
- func (el *Canvas) DrawImage(value DrawImage)
- func (el *Canvas) Fill()
- func (el *Canvas) FillRect(x, y, width, height iotmaker_types.Coordinate)
- func (el *Canvas) FillStyle(value string)
- func (el *Canvas) FillText(text string, x, y, maxWidth iotmaker_types.Coordinate)
- func (el *Canvas) Font(font Font)
- func (el *Canvas) Get(jsParam string, value ...interface{}) iotmaker_types.Coordinate
- func (el *Canvas) GetCanvas() js.Value
- func (el *Canvas) GetContext() js.Value
- func (el *Canvas) GetImageData(x, y, width, height iotmaker_types.Coordinate) [][]color.RGBA
- func (el *Canvas) GlobalAlpha(value iotmaker_types.Coordinate)
- func (el *Canvas) GlobalCompositeOperation(value CanvasCompositeOperationsRule)
- func (el *Canvas) Height() iotmaker_types.Coordinate
- func (el *Canvas) InitializeContext2DById(id string)
- func (el *Canvas) InitializeContext3DById(id string)
- func (el *Canvas) IsPointInPath(path js.Value, x, y iotmaker_types.Coordinate, fillRule CanvasFillRule) bool
- func (el *Canvas) LineCap(value CanvasCapRule)
- func (el *Canvas) LineJoin(value CanvasJoinRule)
- func (el *Canvas) LineTo(x, y iotmaker_types.Coordinate)
- func (el *Canvas) LineWidth(value iotmaker_types.Coordinate)
- func (el *Canvas) MeasureText(text string)
- func (el *Canvas) MiterLimit(value iotmaker_types.Coordinate)
- func (el *Canvas) MoveTo(x, y iotmaker_types.Coordinate)
- func (el *Canvas) PutImageData(imgData js.Value, ...)
- func (el *Canvas) QuadraticCurveTo(cpx, cpy, x, y iotmaker_types.Coordinate)
- func (el *Canvas) Rect(x, y, width, height iotmaker_types.Coordinate)
- func (el *Canvas) Restore()
- func (el *Canvas) Rotate(angle iotmaker_types.Coordinate)
- func (el *Canvas) Save()
- func (el *Canvas) Scale(scaleWidth, scaleHeight iotmaker_types.Coordinate)
- func (el *Canvas) Set(jsParam string, value ...interface{})
- func (el *Canvas) SetTransform(a, b, c, d, e, f iotmaker_types.Coordinate)
- func (el *Canvas) Stroke()
- func (el *Canvas) StrokeRect(x, y, width, height iotmaker_types.Coordinate)
- func (el *Canvas) StrokeStyle(value string)
- func (el *Canvas) StrokeText(text string, x, y, maxWidth iotmaker_types.Coordinate)
- func (el *Canvas) TextAlign(value CanvasFontAlignRule)
- func (el *Canvas) TextBaseline(value CanvasTextBaseLineRule)
- func (el *Canvas) Transform(a, b, c, d, e, f iotmaker_types.Coordinate)
- func (el *Canvas) Translate(x, y iotmaker_types.Coordinate)
- func (el *Canvas) Width() iotmaker_types.Coordinate
- type CanvasCapRule
- type CanvasCompositeOperationsRule
- type CanvasFillRule
- type CanvasFontAlignRule
- type CanvasFontStyleRule
- type CanvasFontVariantRule
- type CanvasFontWeightRule
- type CanvasJoinRule
- type CanvasRepeatRule
- type CanvasTextBaseLineRule
- type Document
- type DrawImage
- type Element
- type Font
- type Platform
Constants ¶
This section is empty.
Variables ¶
var CanvasCapRules = [...]string{
"",
"butt",
"round",
"square",
}
var CanvasCompositeOperationsRules = [...]string{
"",
"source-over",
"source-atop",
"source-in",
"source-out",
"destination-over",
"destination-atop",
"destination-in",
"destination-out",
"lighter",
"copy",
"xor",
}
var CanvasFillRules = [...]string{
"",
"nonzero",
"evenodd",
}
var CanvasFontAlignRules = [...]string{
"",
"start",
"end",
"center",
"left",
"right",
}
var CanvasFontStyleRules = [...]string{
"",
"normal",
"italic",
"oblique",
}
var CanvasFontVariantRules = [...]string{
"",
"normal",
"small-caps",
}
var CanvasFontWeightRules = [...]string{
"",
"normal",
"bold",
"bolder",
"lighter",
"100",
"200",
"300",
"400",
"500",
"600",
"700",
"800",
"900",
}
var CanvasJoinRules = [...]string{
"",
"bevel",
"round",
"miter",
}
var CanvasRepeatRules = [...]string{
"",
"repeat",
"repeat-x",
"repeat-y",
"no-repeat",
}
var CanvasTextBaseLineRules = [...]string{
"",
"alphabetic",
"top",
"hanging",
"middle",
"ideographic",
"bottom",
}
Functions ¶
This section is empty.
Types ¶
type Canvas ¶
en: The Canvas API provides a means for drawing graphics via JavaScript and the HTML <canvas> element. Among other things, it can be used for animation, game graphics, data visualization, photo manipulation, and real-time video processing.
The Canvas API largely focuses on 2D graphics. The WebGL API, which also uses the <canvas> element, draws hardware-accelerated 2D and 3D graphics.
func (*Canvas) AppendToDocumentBody ¶
func (el *Canvas) AppendToDocumentBody()
func (*Canvas) Arc ¶
func (el *Canvas) Arc(x, y, radius, startAngle, endAngle iotmaker_types.Coordinate, anticlockwise bool)
en: Creates an arc/curve (used to create circles, or parts of circles)
x: The horizontal coordinate of the arc's center. y: The vertical coordinate of the arc's center. radius: The arc's radius. Must be positive. startAngle: The angle at which the arc starts in radians, measured from the positive x-axis. endAngle: The angle at which the arc ends in radians, measured from the positive x-axis. anticlockwise: [Optional] An optional Boolean. If true, draws the arc counter-clockwise between the start and end angles. The default is false (clockwise). Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.beginPath(); ctx.arc(100, 75, 50, 0, 2 * Math.PI); ctx.stroke();
func (*Canvas) ArcTo ¶
func (el *Canvas) ArcTo(x1, y1, x2, y2, radius iotmaker_types.Coordinate)
en: Creates an arc/curve between two tangents
x1: The x-axis coordinate of the first control point. y1: The y-axis coordinate of the first control point. x2: The x-axis coordinate of the second control point. y2: The y-axis coordinate of the second control point. radius: The arc's radius. Must be non-negative. Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.beginPath(); ctx.moveTo(20, 20); // Create a starting point ctx.lineTo(100, 20); // Create a horizontal line ctx.arcTo(150, 20, 150, 70, 50); // Create an arc ctx.lineTo(150, 120); // Continue with vertical line ctx.stroke(); // Draw it
func (*Canvas) BeginPath ¶
func (el *Canvas) BeginPath()
en: Begins a path, or resets the current path The beginPath() method begins a path, or resets the current path. Tip: Use moveTo(), lineTo(), quadricCurveTo(), bezierCurveTo(), arcTo(), and arc(), to create paths. Tip: Use the stroke() method to actually draw the path on the canvas.
func (*Canvas) BezierCurveTo ¶
func (el *Canvas) BezierCurveTo(cp1x, cp1y, cp2x, cp2y, x, y iotmaker_types.Coordinate)
en: Creates a cubic Bézier curve
cp1x: The x-axis coordinate of the first control point. cp1y: The y-axis coordinate of the first control point. cp2x: The x-axis coordinate of the second control point. cp2y: The y-axis coordinate of the second control point. x: The x-axis coordinate of the end point. y: The y-axis coordinate of the end point. Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.beginPath(); ctx.moveTo(20, 20); ctx.bezierCurveTo(20, 100, 200, 100, 200, 20); ctx.stroke();
func (*Canvas) ClearRect ¶
func (el *Canvas) ClearRect(x, y, width, height iotmaker_types.Coordinate)
en: Clears the specified pixels within a given rectangle
x: The x-coordinate of the upper-left corner of the rectangle to clear y: The y-coordinate of the upper-left corner of the rectangle to clear width: The width of the rectangle to clear, in pixels height: The height of the rectangle to clear, in pixels The clearRect() method clears the specified pixels within a given rectangle. JavaScript syntax: context.clearRect(x, y, width, height); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.fillStyle = "red"; ctx.fillRect(0, 0, 300, 150); ctx.clearRect(20, 20, 100, 50);
func (*Canvas) Clip ¶
func (el *Canvas) Clip(x, y iotmaker_types.Coordinate)
en: Clips a region of any shape and size from the original canvas
The clip() method clips a region of any shape and size from the original canvas. Tip: Once a region is clipped, all future drawing will be limited to the clipped region (no access to other regions on the canvas). You can however save the current canvas region using the save() method before using the clip() method, and restore it (with the restore() method) any time in the future.
func (*Canvas) ClosePath ¶
func (el *Canvas) ClosePath(x, y iotmaker_types.Coordinate)
en: Creates a path from the current point back to the starting point
The closePath() method creates a path from the current point back to the starting point. Tip: Use the stroke() method to actually draw the path on the canvas. Tip: Use the fill() method to fill the drawing (black is default). Use the fillStyle property to fill with another color/gradient.
func (*Canvas) CreateEvent ¶
func (el *Canvas) CreateEvent()
func (*Canvas) CreateImageData ¶
en: Creates a new, blank ImageData object
width: The width of the new ImageData object, in pixels height: The height of the new ImageData object, in pixels imageData: AnotherImageData object There are two versions of the createImageData() method: 1. This creates a new ImageData object with the specified dimensions (in pixels): JavaScript syntax: var imgData = context.createImageData(width, height); 2. This creates a new ImageData object with the same dimensions as the object specified by anotherImageData (this does not copy the image data): JavaScript syntax: var imgData = context.createImageData(imageData); The createImageData() method creates a new, blank ImageData object. The new object's pixel values are transparent black by default. For every pixel in an ImageData object there are four pieces of information, the RGBA values: R - The color red (from 0-255) G - The color green (from 0-255) B - The color blue (from 0-255) A - The alpha channel (from 0-255; 0 is transparent and 255 is fully visible) So, transparent black indicates: (0, 0, 0, 0). The color/alpha information is held in an array, and since the array contains 4 pieces of information for every pixel, the array's size is 4 times the size of the ImageData object: width*height*4. (An easier way to find the size of the array, is to use ImageDataObject.data.length) The array containing the color/alpha information is stored in the data property of the ImageData object. Tip: After you have manipulated the color/alpha information in the array, you can copy the image data back onto the canvas with the putImageData() method. Examples: The syntax for making the first pixel in the ImageData object red: imgData = ctx.createImageData(100, 100); imgData.data[0] = 255; imgData.data[1] = 0; imgData.data[2] = 0; imgData.data[3] = 255; The syntax for making the second pixel in the ImageData object green: imgData = ctx.createImageData(100, 100); imgData.data[4] = 0; imgData.data[5] = 255; imgData.data[6] = 0; imgData.data[7] = 255; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); var imgData = ctx.createImageData(100, 100); for (var i = 0; i < imgData.data.length; i += 4) { imgData.data[i+0] = 255; imgData.data[i+1] = 0; imgData.data[i+2] = 0; imgData.data[i+3] = 255; } ctx.putImageData(imgData, 10, 10);
todo: fazer
func (*Canvas) CreateLinearGradient ¶
func (el *Canvas) CreateLinearGradient(x0, y0, x1, y1 iotmaker_types.Coordinate)
en: Creates a linear gradient (to use on canvas content)
x0: The x-coordinate of the start point of the gradient y0: The y-coordinate of the start point of the gradient x1: The x-coordinate of the end point of the gradient y1: The y-coordinate of the end point of the gradient The createLinearGradient() method creates a linear gradient object. The gradient can be used to fill rectangles, circles, lines, text, etc. Tip: Use this object as the value to the strokeStyle or fillStyle properties. Tip: Use the addColorStop() method to specify different colors, and where to position the colors in the gradient object. JavaScript syntax: context.createLinearGradient(x0, y0, x1, y1); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); var grd = ctx.createLinearGradient(0, 0, 170, 0); grd.addColorStop(0, "black"); grd.addColorStop(1, "white"); ctx.fillStyle = grd; ctx.fillRect(20, 20, 150, 100);
func (*Canvas) CreatePattern ¶
func (el *Canvas) CreatePattern(image js.Value, repeatRule CanvasRepeatRule)
en: Repeats a specified element in the specified direction
image: Specifies the image, canvas, or video element of the pattern to use repeatedElement repeat: Default. The pattern repeats both horizontally and vertically repeat-x: The pattern repeats only horizontally repeat-y: The pattern repeats only vertically no-repeat: The pattern will be displayed only once (no repeat) The createPattern() method repeats the specified element in the specified direction. The element can be an image, video, or another <canvas> element. The repeated element can be used to draw/fill rectangles, circles, lines etc. JavaScript syntax: context.createPattern(image, "repeat|repeat-x|repeat-y|no-repeat"); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); var img = document.getElementById("lamp"); var pat = ctx.createPattern(img, "repeat"); ctx.rect(0, 0, 150, 100); ctx.fillStyle = pat; ctx.fill();
func (*Canvas) CreateRadialGradient ¶
func (el *Canvas) CreateRadialGradient(x0, y0, r0, x1, y1, r1 iotmaker_types.Coordinate)
en: Creates a radial/circular gradient (to use on canvas content)
x0: The x-coordinate of the starting circle of the gradient y0: The y-coordinate of the starting circle of the gradient r0: The radius of the starting circle x1: The x-coordinate of the ending circle of the gradient y1: The y-coordinate of the ending circle of the gradient r1: The radius of the ending circle Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); var grd = ctx.createRadialGradient(75, 50, 5, 90, 60, 100); grd.addColorStop(0, "red"); grd.addColorStop(1, "white"); // Fill with gradient ctx.fillStyle = grd; ctx.fillRect(10, 10, 150, 100);
func (*Canvas) Data ¶
en: Returns an object that contains image data of a specified ImageData object
JavaScript syntax: imageData.data; The data property returns an object that contains image data of the specified ImageData object. For every pixel in an ImageData object there are four pieces of information, the RGBA values: R - The color red (from 0-255) G - The color green (from 0-255) B - The color blue (from 0-255) A - The alpha channel (from 0-255; 0 is transparent and 255 is fully visible) The color/alpha information is held in an array, and is stored in the data property of the ImageData object. Examples: The syntax for making the first pixel in the ImageData object red: imgData = ctx.createImageData(100, 100); imgData.data[0] = 255; imgData.data[1] = 0; imgData.data[2] = 0; imgData.data[3] = 255; The syntax for making the second pixel in the ImageData object green: imgData = ctx.createImageData(100, 100); imgData.data[4] = 0; imgData.data[5] = 255; imgData.data[6] = 0; imgData.data[7] = 255; Tip: Look at createImageData(), getImageData(), and putImageData() to learn more about the ImageData object. Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); var imgData = ctx.createImageData(100, 100); for (var i = 0; i < imgData.data.length; i += 4) { imgData.data[i+0] = 255; imgData.data[i+1] = 0; imgData.data[i+2] = 0; imgData.data[i+3] = 255; } ctx.putImageData(imgData, 10, 10);
func (*Canvas) DrawImage ¶
en: Draws an image, canvas, or video onto the canvas
img: Specifies the image, canvas, or video element to use sx: Optional. The x coordinate where to start clipping sy: Optional. The y coordinate where to start clipping swidth: Optional. The width of the clipped image sheight: Optional. The height of the clipped image x: The x coordinate where to place the image on the canvas y: The y coordinate where to place the image on the canvas width: Optional. The width of the image to use (stretch or reduce the image) height: Optional. The height of the image to use (stretch or reduce the image) The drawImage() method draws an image, canvas, or video onto the canvas. The drawImage() method can also draw parts of an image, and/or increase/reduce the image size. Position the image on the canvas: JavaScript syntax: context.drawImage(img, x, y); Position the image on the canvas, and specify width and height of the image: JavaScript syntax: context.drawImage(img, x, y, width, height); Clip the image and position the clipped part on the canvas: JavaScript syntax: context.drawImage(img, sx, sy, swidth, sheight, x, y, width, height); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); var img = document.getElementById("scream"); ctx.drawImage(img, 10, 10);
func (*Canvas) Fill ¶
func (el *Canvas) Fill()
en: Fills the current drawing (path)
The fill() method fills the current drawing (path). The default color is black. Tip: Use the fillStyle property to fill with another color/gradient. Note: If the path is not closed, the fill() method will add a line from the last point to the startpoint of the path to close the path (like closePath()), and then fill the path.
func (*Canvas) FillRect ¶
func (el *Canvas) FillRect(x, y, width, height iotmaker_types.Coordinate)
en: Draws a "filled" rectangle
x: The x-coordinate of the upper-left corner of the rectangle y: The y-coordinate of the upper-left corner of the rectangle width: The width of the rectangle, in pixels height: The height of the rectangle, in pixels The fillRect() method draws a "filled" rectangle. The default color of the fill is black. Tip: Use the fillStyle property to set a color, gradient, or pattern used to fill the drawing. JavaScript syntax: context.fillRect(x, y, width, height); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.fillRect(20, 20, 150, 100);
func (*Canvas) FillStyle ¶
en: Sets or returns the color, gradient, or pattern used to fill the drawing
The fillStyle property sets or returns the color, gradient, or pattern used to fill the drawing. Default value: #000000 JavaScript syntax: context.fillStyle = color|gradient|pattern;
func (*Canvas) FillText ¶
func (el *Canvas) FillText(text string, x, y, maxWidth iotmaker_types.Coordinate)
en: Draws "filled" text on the canvas
text: Specifies the text that will be written on the canvas x: The x coordinate where to start painting the text (relative to the canvas) y: The y coordinate where to start painting the text (relative to the canvas) maxWidth: Optional. The maximum allowed width of the text, in pixels The fillText() method draws filled text on the canvas. The default color of the text is black. Tip: Use the font property to specify font and font size, and use the fillStyle property to render the text in another color/gradient. JavaScript syntax: context.fillText(text, x, y, maxWidth); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.font = "20px Georgia"; ctx.fillText("Hello World!", 10, 50); ctx.font = "30px Verdana"; // Create gradient var gradient = ctx.createLinearGradient(0, 0, c.width, 0); gradient.addColorStop("0", "magenta"); gradient.addColorStop("0.5", "blue"); gradient.addColorStop("1.0", "red"); // Fill with gradient ctx.fillStyle = gradient; ctx.fillText("Big smile!", 10, 90);
func (*Canvas) Font ¶
en: Sets or returns the current font properties for text content
font-style: Specifies the font style. Possible values: normal | italic | oblique font-variant: Specifies the font variant. Possible values: normal | small-caps font-weight: Specifies the font weight. Possible values: normal | bold | bolder | lighter | 100 | 200 | 300 | 400 | 500 | 600 | 700 | 800 | 900 font-size/line-height: Specifies the font size and the line-height, in pixels font-family: Specifies the font family caption: Use the font captioned controls (like buttons, drop-downs, etc.) icon: Use the font used to label icons menu: Use the font used in menus (drop-down menus and menu lists) message-box: Use the font used in dialog boxes small-caption: Use the font used for labeling small controls status-bar: Use the fonts used in window status bar The font property sets or returns the current font properties for text content on the canvas. The font property uses the same syntax as the CSS font property. Default value: 10px sans-serif JavaScript syntax: context.font = "italic small-caps bold 12px arial"; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.font = "30px Arial"; ctx.fillText("Hello World", 10, 50);
func (*Canvas) Get ¶
func (el *Canvas) Get(jsParam string, value ...interface{}) iotmaker_types.Coordinate
func (*Canvas) GetContext ¶
func (*Canvas) GetImageData ¶
func (el *Canvas) GetImageData(x, y, width, height iotmaker_types.Coordinate) [][]color.RGBA
en: Returns an ImageData object that copies the pixel data for the specified rectangle on a canvas
x: The x coordinate (in pixels) of the upper-left corner to start copy from y: The y coordinate (in pixels) of the upper-left corner to start copy from width: The width of the rectangular area you will copy height: The height of the rectangular area you will copy return: [x][y]color.RGBA Note: return x and y are relative to the coordinate (0,0) on the image JavaScript syntax: context.getImageData(x, y, width, height); The getImageData() method returns an ImageData object that copies the pixel data for the specified rectangle on a canvas. Note: The ImageData object is not a picture, it specifies a part (rectangle) on the canvas, and holds information of every pixel inside that rectangle. For every pixel in an ImageData object there are four pieces of information, the RGBA values: R - The color red (from 0-255) G - The color green (from 0-255) B - The color blue (from 0-255) A - The alpha channel (from 0-255; 0 is transparent and 255 is fully visible) The color/alpha information is held in an array, and is stored in the data property of the ImageData object. Tip: After you have manipulated the color/alpha information in the array, you can copy the image data back onto the canvas with the putImageData() method. Example: The code for getting color/alpha information of the first pixel in the returned ImageData object: red = imgData.data[0]; green = imgData.data[1]; blue = imgData.data[2]; alpha = imgData.data[3]; Tip: You can also use the getImageData() method to invert the color of every pixels of an image on the canvas. Loop through all the pixels and change the color values using this formula: red = 255-old_red; green = 255-old_green; blue = 255-old_blue; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.fillStyle = "red"; ctx.fillRect(10, 10, 50, 50); function copy() { var imgData = ctx.getImageData(10, 10, 50, 50); ctx.putImageData(imgData, 10, 70); }
func (*Canvas) GlobalAlpha ¶
func (el *Canvas) GlobalAlpha(value iotmaker_types.Coordinate)
en: Sets or returns the current alpha or transparency value of the drawing
number: The transparency value. Must be a number between 0.0 (fully transparent) and 1.0 (no transparancy) Default value: 1.0 JavaScript syntax: context.globalAlpha = number; The globalAlpha property sets or returns the current alpha or transparency value of the drawing. The globalAlpha property value must be a number between 0.0 (fully transparent) and 1.0 (no transparancy) Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.fillStyle = "red"; ctx.fillRect(20, 20, 75, 50); // Turn transparency on ctx.globalAlpha = 0.2; ctx.fillStyle = "blue"; ctx.fillRect(50, 50, 75, 50); ctx.fillStyle = "green"; ctx.fillRect(80, 80, 75, 50);
func (*Canvas) GlobalCompositeOperation ¶
func (el *Canvas) GlobalCompositeOperation(value CanvasCompositeOperationsRule)
en: Sets or returns how a new image are drawn onto an existing image
The globalCompositeOperation property sets or returns how a source (new) image are drawn onto a destination (existing) image. source image = drawings you are about to place onto the canvas. destination image = drawings that are already placed onto the canvas. Default value: source-over JavaScript syntax: context.globalCompositeOperation = "source-in"; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.fillStyle = "red"; ctx.fillRect(20, 20, 75, 50); ctx.globalCompositeOperation = "source-over"; ctx.fillStyle = "blue"; ctx.fillRect(50, 50, 75, 50); ctx.fillStyle = "red"; ctx.fillRect(150, 20, 75, 50); ctx.globalCompositeOperation = "destination-over"; ctx.fillStyle = "blue"; ctx.fillRect(180, 50, 75, 50);
func (*Canvas) Height ¶
func (el *Canvas) Height() iotmaker_types.Coordinate
en: Returns the height of an ImageData object
The height property returns the height of an ImageData object, in pixels. Tip: Look at createImageData(), getImageData(), and putImageData() to learn more about the ImageData object. JavaScript syntax: imgData.height;
func (*Canvas) InitializeContext2DById ¶
todo: tem que saber que id é um canvas
func (*Canvas) InitializeContext3DById ¶
todo: tem que saber que id é um canvas
func (*Canvas) IsPointInPath ¶
func (el *Canvas) IsPointInPath(path js.Value, x, y iotmaker_types.Coordinate, fillRule CanvasFillRule) bool
en: Returns true if the specified point is in the current path, otherwise false
x: The x-axis coordinate of the point to check. y: The y-axis coordinate of the point to check. fillRule: The algorithm by which to determine if a point is inside or outside the path. "nonzero": The non-zero winding rule. Default rule. "evenodd": The even-odd winding rule. path: A Path2D path to check against. If unspecified, the current path is used. Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.rect(20, 20, 150, 100); if (ctx.isPointInPath(20, 50)) { ctx.stroke(); };
func (*Canvas) LineCap ¶
func (el *Canvas) LineCap(value CanvasCapRule)
en: Sets or returns the style of the end caps for a line
PlatformBasicType: "butt|round|square" The lineCap property sets or returns the style of the end caps for a line. Note: The value "round" and "square" make the lines slightly longer. Default value: butt JavaScript syntax: context.lineCap = "butt|round|square"; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.beginPath(); ctx.lineCap = "round"; ctx.moveTo(20, 20); ctx.lineTo(20, 200); ctx.stroke();
func (*Canvas) LineJoin ¶
func (el *Canvas) LineJoin(value CanvasJoinRule)
en: Sets or returns the type of corner created, when two lines meet
PlatformBasicType: "bevel|round|miter" The lineJoin property sets or returns the type of corner created, when two lines meet. Note: The "miter" value is affected by the miterLimit property. Default value: miter JavaScript syntax: context.lineJoin = "bevel|round|miter"; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.beginPath(); ctx.lineJoin = "round"; ctx.moveTo(20, 20); ctx.lineTo(100, 50); ctx.lineTo(20, 100); ctx.stroke();
func (*Canvas) LineTo ¶
func (el *Canvas) LineTo(x, y iotmaker_types.Coordinate)
en: Adds a new point and creates a line from that point to the last specified point in the canvas
x: The x-coordinate of where to create the line to y: The y-coordinate of where to create the line to The lineTo() method adds a new point and creates a line from that point to the last specified point in the canvas (this method does not draw the line). Tip: Use the stroke() method to actually draw the path on the canvas.
func (*Canvas) LineWidth ¶
func (el *Canvas) LineWidth(value iotmaker_types.Coordinate)
en: Sets or returns the current line width
PlatformBasicType: The current line width, in pixels The lineWidth property sets or returns the current line width, in pixels. Default value: 1 JavaScript syntax: context.lineWidth = number; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.lineWidth = 10; ctx.strokeRect(20, 20, 80, 100);
func (*Canvas) MeasureText ¶
en: Returns an object that contains the width of the specified text
text: The text to be measured The measureText() method returns an object that contains the width of the specified text, in pixels. Tip: Use this method if you need to know the width of a text, before writing it on the canvas. JavaScript syntax: context.measureText(text).width; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.font = "30px Arial"; var txt = "Hello World" ctx.fillText("width:" + ctx.measureText(txt).width, 10, 50) ctx.fillText(txt, 10, 100);
func (*Canvas) MiterLimit ¶
func (el *Canvas) MiterLimit(value iotmaker_types.Coordinate)
en: Sets or returns the maximum miter length
PlatformBasicType: A positive number that specifies the maximum miter length. If the current miter length exceeds the miterLimit, the corner will display as lineJoin "bevel" The miterLimit property sets or returns the maximum miter length. The miter length is the distance between the inner corner and the outer corner where two lines meet. Default value: 10 JavaScript syntax: context.miterLimit = number; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.lineWidth = 10; ctx.lineJoin = "miter"; ctx.miterLimit = 5; ctx.moveTo(20, 20); ctx.lineTo(50, 27); ctx.lineTo(20, 34); ctx.stroke();
func (*Canvas) MoveTo ¶
func (el *Canvas) MoveTo(x, y iotmaker_types.Coordinate)
en: Moves the path to the specified point in the canvas, without creating a line
x: The x-coordinate of where to move the path to y: The y-coordinate of where to move the path to The moveTo() method moves the path to the specified point in the canvas, without creating a line. Tip: Use the stroke() method to actually draw the path on the canvas.
func (*Canvas) PutImageData ¶
func (el *Canvas) PutImageData(imgData js.Value, x, y, dirtyX, dirtyY, dirtyWidth, dirtyHeight iotmaker_types.Coordinate)
en: Puts the image data (from a specified ImageData object) back onto the canvas
imgData: Specifies the ImageData object to put back onto the canvas x: The x-coordinate, in pixels, of the upper-left corner of where to place the image on the canvas y: The y-coordinate, in pixels, of the upper-left corner of where to place the image on the canvas dirtyX: Optional. The x-coordinate, in pixels, of the upper-left corner of where to start drawing the image. Default 0 dirtyY: Optional. The y-coordinate, in pixels, of the upper-left corner of where to start drawing the image. Default 0 dirtyWidth: Optional. The width to use when drawing the image on the canvas. Default: the width of the extracted image dirtyHeight: Optional. The height to use when drawing the image on the canvas. Default: the height of the extracted image JavaScript syntax: context.putImageData(imgData, x, y, dirtyX, dirtyY, dirtyWidth, dirtyHeight); The putImageData() method puts the image data (from a specified ImageData object) back onto the canvas. Tip: Read about the getImageData() method that copies the pixel data for a specified rectangle on a canvas. Tip: Read about the createImageData() method that creates a new, blank ImageData object. Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.fillStyle = "red"; ctx.fillRect(10, 10, 50, 50); function copy() { var imgData = ctx.getImageData(10, 10, 50, 50); ctx.putImageData(imgData, 10, 70); }
todo: fazer
func (*Canvas) QuadraticCurveTo ¶
func (el *Canvas) QuadraticCurveTo(cpx, cpy, x, y iotmaker_types.Coordinate)
en: Creates a quadratic Bézier curve
cpx: The x-axis coordinate of the control point. cpy: The y-axis coordinate of the control point. x: The x-axis coordinate of the end point. y: The y-axis coordinate of the end point. Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.beginPath(); ctx.moveTo(20, 20); ctx.quadraticCurveTo(20, 100, 200, 20); ctx.stroke();
func (*Canvas) Rect ¶
func (el *Canvas) Rect(x, y, width, height iotmaker_types.Coordinate)
en: Creates a rectangle
x: The x-coordinate of the upper-left corner of the rectangle y: The y-coordinate of the upper-left corner of the rectangle width: The width of the rectangle, in pixels height: The height of the rectangle, in pixels The rect() method creates a rectangle. Tip: Use the stroke() or the fill() method to actually draw the rectangle on the canvas. JavaScript syntax: context.rect(x, y, width, height); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.rect(20, 20, 150, 100); ctx.stroke();
func (*Canvas) Restore ¶
func (el *Canvas) Restore()
en: Returns previously saved path state and attributes
func (*Canvas) Rotate ¶
func (el *Canvas) Rotate(angle iotmaker_types.Coordinate)
en: Rotates the current drawing
angle: The rotation angle, in radians. To calculate from degrees to radians: degrees*Math.PI/180. Example: to rotate 5 degrees, specify the following: 5*Math.PI/180 The rotate() method rotates the current drawing. Note: The rotation will only affect drawings made AFTER the rotation is done. JavaScript syntax: context.rotate(angle); Example: var c = document.getElementById("my Canvas"); var ctx = c.getContext("2d"); ctx.rotate(20 * Math.PI / 180); ctx.fillRect(50, 20, 100, 50);
func (*Canvas) Scale ¶
func (el *Canvas) Scale(scaleWidth, scaleHeight iotmaker_types.Coordinate)
en: Scales the current drawing bigger or smaller
scaleWidth: Scales the width of the current drawing (1=100%, 0.5=50%, 2=200%, etc.) scaleHeight: Scales the height of the current drawing (1=100%, 0.5=50%, 2=200%, etc.) The scale() method scales the current drawing, bigger or smaller. Note: If you scale a drawing, all future drawings will also be scaled. The positioning will also be scaled. If you scale(2,2); drawings will be positioned twice as far from the left and top of the canvas as you specify. JavaScript syntax: context.scale(scalewidth, scaleheight); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.strokeRect(5, 5, 25, 15); ctx.scale(2, 2); ctx.strokeRect(5, 5, 25, 15);
func (*Canvas) SetTransform ¶
func (el *Canvas) SetTransform(a, b, c, d, e, f iotmaker_types.Coordinate)
en: Resets the current transform to the identity matrix. Then runs transform()
a: Scales the drawings horizontally b: Skews the drawings horizontally c: Skews the drawings vertically d: Scales the drawings vertically e: Moves the the drawings horizontally f: Moves the the drawings vertically Each object on the canvas has a current transformation matrix. The setTransform() method resets the current transform to the identity matrix, and then runs transform() with the same arguments. In other words, the setTransform() method lets you scale, rotate, move, and skew the current context. Note: The transformation will only affect drawings made after the setTransform method is called. JavaScript syntax: context.setTransform(a, b, c, d, e, f); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.fillStyle = "yellow"; ctx.fillRect(0, 0, 250, 100) ctx.setTransform(1, 0.5, -0.5, 1, 30, 10); ctx.fillStyle = "red"; ctx.fillRect(0, 0, 250, 100); ctx.setTransform(1, 0.5, -0.5, 1, 30, 10); ctx.fillStyle = "blue"; ctx.fillRect(0, 0, 250, 100);
func (*Canvas) Stroke ¶
func (el *Canvas) Stroke()
en: Actually draws the path you have defined
The stroke() method actually draws the path you have defined with all those moveTo() and lineTo() methods. The default color is black. Tip: Use the strokeStyle property to draw with another color/gradient.
func (*Canvas) StrokeRect ¶
func (el *Canvas) StrokeRect(x, y, width, height iotmaker_types.Coordinate)
en: Draws a rectangle (no fill)
x: The x-coordinate of the upper-left corner of the rectangle y: The y-coordinate of the upper-left corner of the rectangle width: The width of the rectangle, in pixels height: The height of the rectangle, in pixels The strokeRect() method draws a rectangle (no fill). The default color of the stroke is black. Tip: Use the strokeStyle property to set a color, gradient, or pattern to style the stroke. JavaScript syntax: context.strokeRect(x, y, width, height); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.strokeRect(20, 20, 150, 100);
func (*Canvas) StrokeStyle ¶
en: Sets or returns the color, gradient, or pattern used for strokes
The strokeStyle property sets or returns the color, gradient, or pattern used for strokes. Default value: #000000 JavaScript syntax: context.strokeStyle = color|gradient|pattern;
func (*Canvas) StrokeText ¶
func (el *Canvas) StrokeText(text string, x, y, maxWidth iotmaker_types.Coordinate)
en: Draws text on the canvas (no fill)
text: Specifies the text that will be written on the canvas x: The x coordinate where to start painting the text (relative to the canvas) y: The y coordinate where to start painting the text (relative to the canvas) maxWidth: Optional. The maximum allowed width of the text, in pixels The strokeText() method draws text (with no fill) on the canvas. The default color of the text is black. Tip: Use the font property to specify font and font size, and use the strokeStyle property to render the text in another color/gradient. JavaScript syntax: context.strokeText(text, x, y, maxWidth); var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.font = "20px Georgia"; ctx.strokeText("Hello World!", 10, 50); ctx.font = "30px Verdana"; // Create gradient var gradient = ctx.createLinearGradient(0, 0, c.width, 0); gradient.addColorStop("0", "magenta"); gradient.addColorStop("0.5", "blue"); gradient.addColorStop("1.0", "red"); // Fill with gradient ctx.strokeStyle = gradient; ctx.strokeText("Big smile!", 10, 90);
func (*Canvas) TextAlign ¶
func (el *Canvas) TextAlign(value CanvasFontAlignRule)
en: Sets or returns the current alignment for text content
The textAlign property sets or returns the current alignment for text content, according to the anchor point. Normally, the text will START in the position specified, however, if you set textAlign="right" and place the text in position 150, it means that the text should END in position 150. Tip: Use the fillText() or the strokeText() method to actually draw and position the text on the canvas. Default value: start JavaScript syntax: context.textAlign = "center | end | left | right | start"; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); // Create a red line in position 150 ctx.strokeStyle = "red"; ctx.moveTo(150, 20); ctx.lineTo(150, 170); ctx.stroke(); ctx.font = "15px Arial"; // Show the different textAlign values ctx.textAlign = "start"; ctx.fillText("textAlign = start", 150, 60); ctx.textAlign = "end"; ctx.fillText("textAlign = end", 150, 80); ctx.textAlign = "left"; ctx.fillText("textAlign = left", 150, 100); ctx.textAlign = "center"; ctx.fillText("textAlign = center", 150, 120); ctx.textAlign = "right"; ctx.fillText("textAlign = right", 150, 140);
func (*Canvas) TextBaseline ¶
func (el *Canvas) TextBaseline(value CanvasTextBaseLineRule)
en: Sets or returns the current text baseline used when drawing text
PlatformBasicType: alphabetic: Default. The text baseline is the normal alphabetic baseline top: The text baseline is the top of the em square hanging: The text baseline is the hanging baseline middle: The text baseline is the middle of the em square ideographic: The text baseline is the ideographic baseline bottom: The text baseline is the bottom of the bounding box The textBaseline property sets or returns the current text baseline used when drawing text. Note: The fillText() and strokeText() methods will use the specified textBaseline value when positioning the text on the canvas. Default value: alphabetic JavaScript syntax: context.textBaseline = "alphabetic|top|hanging|middle|ideographic|bottom"; Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); //Draw a red line at y=100 ctx.strokeStyle = "red"; ctx.moveTo(5, 100); ctx.lineTo(395, 100); ctx.stroke(); ctx.font = "20px Arial" //Place each word at y=100 with different textBaseline values ctx.textBaseline = "top"; ctx.fillText("Top", 5, 100); ctx.textBaseline = "bottom"; ctx.fillText("Bottom", 50, 100); ctx.textBaseline = "middle"; ctx.fillText("Middle", 120, 100); ctx.textBaseline = "alphabetic"; ctx.fillText("Alphabetic", 190, 100); ctx.textBaseline = "hanging"; ctx.fillText("Hanging", 290, 100);
func (*Canvas) Transform ¶
func (el *Canvas) Transform(a, b, c, d, e, f iotmaker_types.Coordinate)
en: Replaces the current transformation matrix for the drawing
a: Scales the drawing horizontally b: Skew the the drawing horizontally c: Skew the the drawing vertically d: Scales the drawing vertically e: Moves the the drawing horizontally f: Moves the the drawing vertically Each object on the canvas has a current transformation matrix. The transform() method replaces the current transformation matrix. It multiplies the current transformation matrix with the matrix described by: a | c | e ----------- b | d | f ----------- 0 | 0 | 1 In other words, the transform() method lets you scale, rotate, move, and skew the current context. Note: The transformation will only affect drawings made after the transform() method is called. Note: The transform() method behaves relatively to other transformations made by rotate(), scale(), translate(), or transform(). Example: If you already have set your drawing to scale by two, and the transform() method scales your drawings by two, your drawings will now scale by four. Tip: Check out the setTransform() method, which does not behave relatively to other transformations. JavaScript syntax: context.transform(a, b, c, d, e, f); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.fillStyle = "yellow"; ctx.fillRect(0, 0, 250, 100) ctx.transform(1, 0.5, -0.5, 1, 30, 10); ctx.fillStyle = "red"; ctx.fillRect(0, 0, 250, 100); ctx.transform(1, 0.5, -0.5, 1, 30, 10); ctx.fillStyle = "blue"; ctx.fillRect(0, 0, 250, 100);
func (*Canvas) Translate ¶
func (el *Canvas) Translate(x, y iotmaker_types.Coordinate)
en: Remaps the (0,0) position on the canvas
x: The value to add to horizontal (x) coordinates y: The value to add to vertical (y) coordinates The translate() method remaps the (0,0) position on the canvas. Note: When you call a method such as fillRect() after translate(), the value is added to the x- and y-coordinate values. JavaScript syntax: context.translate(x, y); Example: var c = document.getElementById("myCanvas"); var ctx = c.getContext("2d"); ctx.fillRect(10, 10, 100, 50); ctx.translate(70, 70); ctx.fillRect(10, 10, 100, 50);
func (*Canvas) Width ¶
func (el *Canvas) Width() iotmaker_types.Coordinate
en: Returns the width of an ImageData object
The width property returns the width of an ImageData object, in pixels. Tip: Look at createImageData(), getImageData(), and putImageData() to learn more about the ImageData object. JavaScript syntax: imgData.width;
type CanvasCapRule ¶
type CanvasCapRule int
const ( // en: Default. A flat edge is added to each end of the line KCapRuleButt CanvasCapRule = iota + 1 // en: A rounded end cap is added to each end of the line KCapRuleRound // en: A square end cap is added to each end of the line KCapRuleSquare )
func (CanvasCapRule) String ¶
func (el CanvasCapRule) String() string
type CanvasCompositeOperationsRule ¶
type CanvasCompositeOperationsRule int
const ( // en: Default. Displays the source image over the destination image KCompositeOperationsRuleSourceOver CanvasCompositeOperationsRule = iota + 1 // en: Displays the source image on top of the destination image. The part of the source image that is outside the // destination image is not shown KCompositeOperationsRuleSourceAtop // en: Displays the source image in to the destination image. Only the part of the source image that is INSIDE the // destination image is shown, and the destination image is transparent KCompositeOperationsRuleSourceIn // en: Displays the source image out of the destination image. Only the part of the source image that is OUTSIDE the // destination image is shown, and the destination image is transparent KCompositeOperationsRuleSourceOut // en: Displays the destination image over the source image KCompositeOperationsRuleDestinationOver // en: Displays the destination image on top of the source image. The part of the destination image that is outside // the source image is not shown KCompositeOperationsRuleDestinationAtop // en: Displays the destination image in to the source image. Only the part of the destination image that is INSIDE // the source image is shown, and the source image is transparent KCompositeOperationsRuleDestinationIn // en: Displays the destination image out of the source image. Only the part of the destination image that is OUTSIDE // the source image is shown, and the source image is transparent KCompositeOperationsRuleDestinationOut // en: Displays the source image + the destination image KCompositeOperationsRuleLighter // en: Displays the source image. The destination image is ignored KCompositeOperationsRuleCopy // en: The source image is combined by using an exclusive OR with the destination image KCompositeOperationsRuleXor )
func (CanvasCompositeOperationsRule) String ¶
func (el CanvasCompositeOperationsRule) String() string
type CanvasFillRule ¶
type CanvasFillRule int
const ( // en: In two-dimensional computer graphics, the non-zero winding rule is a means of determining whether a given point // falls within an enclosed curve. Unlike the similar even-odd rule, it relies on knowing the direction of stroke for // each part of the curve. KFillRuleNonZero CanvasFillRule = iota + 1 // en: The even–odd rule is an algorithm implemented in vector-based graphic software,[1] like the PostScript language // and Scalable Vector Graphics (SVG), which determines how a graphical shape with more than one closed outline will // be filled. Unlike the nonzero-rule algorithm, this algorithm will alternatively color and leave uncolored shapes // defined by nested closed paths irrespective of their winding. KFillRuleEvenOdd )
func (CanvasFillRule) String ¶
func (el CanvasFillRule) String() string
type CanvasFontAlignRule ¶
type CanvasFontAlignRule int
const ( // en: Default. The text starts at the specified position KFontAlignRuleStart CanvasFontAlignRule = iota + 1 // en: The text ends at the specified position KFontAlignRuleEnd // en: The center of the text is placed at the specified position KFontAlignRuleCenter // en: The text starts at the specified position KFontAlignRuleLeft // en: The text ends at the specified position KFontAlignRuleRight )
func (CanvasFontAlignRule) String ¶
func (el CanvasFontAlignRule) String() string
type CanvasFontStyleRule ¶
type CanvasFontStyleRule int
const ( // en: Specifies the font style normal. KFontStyleRuleNormal CanvasFontStyleRule = iota + 1 // en: Specifies the font style italic. KFontStyleRuleItalic // en: Specifies the font style oblique. KFontStyleRuleOblique )
func (CanvasFontStyleRule) String ¶
func (el CanvasFontStyleRule) String() string
type CanvasFontVariantRule ¶
type CanvasFontVariantRule int
const ( // en: Specifies the font variant normal. KFontVariantRuleNormal CanvasFontVariantRule = iota + 1 // en: Specifies the font variant small-caps. KFontVariantRuleSmallCaps )
func (CanvasFontVariantRule) String ¶
func (el CanvasFontVariantRule) String() string
type CanvasFontWeightRule ¶
type CanvasFontWeightRule int
const ( // en: Specifies the font weight normal. KFontWeightRuleNormal CanvasFontWeightRule = iota + 1 // en: Specifies the font weight bold. KFontWeightRuleBold // en: Specifies the font weight bolder. KFontWeightRuleBolder // en: Specifies the font weight lighter. KFontWeightRuleLighter // en: Specifies the font weight 100. KFontWeightRule100 // en: Specifies the font weight 200. KFontWeightRule200 // en: Specifies the font weight 300. KFontWeightRule300 // en: Specifies the font weight 400. KFontWeightRule400 // en: Specifies the font weight 500. KFontWeightRule500 // en: Specifies the font weight 600. KFontWeightRule600 // en: Specifies the font weight 700. KFontWeightRule700 // en: Specifies the font weight 800. KFontWeightRule800 // en: Specifies the font weight 900. KFontWeightRule900 )
func (CanvasFontWeightRule) String ¶
func (el CanvasFontWeightRule) String() string
type CanvasJoinRule ¶
type CanvasJoinRule int
const ( // en: Creates a beveled corner KJoinRuleBevel CanvasJoinRule = iota + 1 // en: A Creates a rounded corner KJoinRuleRound // en: Default. Creates a sharp corner KJoinRuleMiter )
func (CanvasJoinRule) String ¶
func (el CanvasJoinRule) String() string
type CanvasRepeatRule ¶
type CanvasRepeatRule int
const ( // en: Default. The pattern repeats both horizontally and vertically KRepeatRuleRepeat CanvasRepeatRule = iota + 1 // en: The pattern repeats only horizontally KRepeatRuleRepeatX // en: The pattern repeats only vertically KRepeatRuleRepeatY // en: The pattern will be displayed only once (no repeat) KRepeatRuleNoRepeat )
func (CanvasRepeatRule) String ¶
func (el CanvasRepeatRule) String() string
type CanvasTextBaseLineRule ¶
type CanvasTextBaseLineRule int
const ( // en: Default. The text baseline is the normal alphabetic baseline KTextBaseLineRuleAlphabetic CanvasTextBaseLineRule = iota + 1 // en: The text baseline is the top of the em square KTextBaseLineRuleTop // en: The text baseline is the hanging baseline KTextBaseLineRuleHanging // en: The text baseline is the middle of the em square KTextBaseLineRuleMiddle // en: The text baseline is the ideographic baseline KTextBaseLineRuleIdeographic // en: The text baseline is the bottom of the bounding box KTextBaseLineRuleBottom )
func (CanvasTextBaseLineRule) String ¶
func (el CanvasTextBaseLineRule) String() string
type Document ¶
type Document struct {
// contains filtered or unexported fields
}
func (*Document) AppendChild ¶
func (*Document) AppendChildToDocumentBody ¶
func (el *Document) AppendChildToDocumentBody(value interface{})
func (*Document) Initialize ¶
func (el *Document) Initialize()
type DrawImage ¶
type DrawImage struct { // en: Specifies the image, canvas, or video element to use Image js.Value // en: The x coordinate where to place the image on the canvas X iotmaker_types.Coordinate // en: The y coordinate where to place the image on the canvas Y iotmaker_types.Coordinate // en: Optional. The x coordinate where to start clipping SX iotmaker_types.Coordinate // en: Optional. The y coordinate where to start clipping SY iotmaker_types.Coordinate // en: Optional. The width of the clipped image SWidth iotmaker_types.Coordinate // en: Optional. The height of the clipped image SHeight iotmaker_types.Coordinate // en: Optional. The width of the image to use (stretch or reduce the image) Width iotmaker_types.Coordinate // en: Optional. The height of the image to use (stretch or reduce the image) Height iotmaker_types.Coordinate }
type Element ¶
func (*Element) AppendElementToDocumentBody ¶
func (el *Element) AppendElementToDocumentBody()
func (*Element) InitializeDocument ¶
func (el *Element) InitializeDocument()
func (*Element) InitializeExistentElementById ¶
type Font ¶
type Font struct { // en: Specifies the font style. Style CanvasFontStyleRule // en: Specifies the font variant. Variant CanvasFontVariantRule // en: Specifies the font weight. Weight CanvasFontWeightRule // en: Specifies the font size and the line-height, in pixels Size iotmaker_types.Coordinate // en: Specifies the font family Family string // en: Use the font captioned controls (like buttons, drop-downs, etc.) Caption string // en: Use the font used to label icons Icon string // en: Use the font used in menus (drop-down menus and menu lists) Menu string // en: Use the font used in dialog boxes MessageBox string // en: Use the font used for labeling small controls SmallCaption string // en: Use the fonts used in window status bar StatusBar string }
Source Files ¶
- appendToDocumentBody.go
- arc.go
- arcTo.go
- beginPath.go
- bezierCurveTo.go
- clearRect.go
- clip.go
- closePath.go
- const.go
- createEvent.go
- createImageData.go
- createLinearGradient.go
- createPattern.go
- createRadialGradient.go
- data.go
- drawImage.go
- fill.go
- fillRect.go
- fillStyle.go
- fillText.go
- font.go
- getCanvas.go
- getContext.go
- getImageData.go
- globalAlpha.go
- globalCompositeOperation.go
- height.go
- initializeContext2DById.go
- initializeContext3DById.go
- isPointInPath.go
- jsCall.go
- jsGet.go
- jsSet.go
- lineCap.go
- lineJoin.go
- lineTo.go
- lineWidth.go
- measureText.go
- miterLimit.go
- moveTo.go
- putImageData.go
- quadraticCurveTo.go
- rect.go
- restore.go
- rotate.go
- save.go
- scale.go
- setTransform.go
- stroke.go
- strokeRect.go
- strokeStyle.go
- strokeText.go
- textAlign.go
- textBaseline.go
- toDataURL.go
- transform.go
- translate.go
- typeCanvas.go
- typeCanvasCapRulle.go
- typeCanvasFont.go
- typeCanvasFontAlignRule.go
- typeCanvasFontStyleRule.go
- typeCanvasFontVariantRule.go
- typeCanvasFontWeightRule.go
- typeCanvasImageDrawing.go
- typeCanvasJoinRule.go
- typeCanvasTextBaseLineRule.go
- typeCompositeOperationsRule.go
- typeDocument.go
- typeElement.go
- typeFillRule.go
- typePlatform.go
- typeRepeatRule.go
- width.go