KasmVNC/kasmweb/docs/API-internal.md

1. Internal Modules

The noVNC client is composed of several internal modules that handle rendering, input, networking, etc. Each of the modules is designed to be cross-browser and independent from each other.

Note however that the API of these modules is not guaranteed to be stable, and this documentation is not maintained as well as the official external API.

1.1 Module List

• Mouse (core/input/mouse.js): Mouse input event handler with limited touch support.

• Keyboard (core/input/keyboard.js): Keyboard input event handler with non-US keyboard support. Translates keyDown and keyUp events to X11 keysym values.

• Display (core/display.js): Efficient 2D rendering abstraction layered on the HTML5 canvas element.

• Websock (core/websock.js): Websock client from websockify with transparent binary data support. Websock API wiki page.

1.2 Callbacks

For the Mouse, Keyboard and Display objects the callback functions are assigned to configuration attributes, just as for the RFB object. The WebSock module has a method named 'on' that takes two parameters: the callback event name, and the callback function.

2. Modules

2.1 Mouse Module

2.1.1 Configuration Attributes

name	type	mode	default	description
touchButton	int	RW	1	Button mask (1, 2, 4) for which click to send on touch devices. 0 means ignore clicks.

2.1.2 Methods

name	parameters	description
grab	()	Begin capturing mouse events
ungrab	()	Stop capturing mouse events

2.1.2 Callbacks

name	parameters	description
onmousebutton	(x, y, down, bmask)	Handler for mouse button click/release
onmousemove	(x, y)	Handler for mouse movement

2.2 Keyboard Module

2.2.1 Configuration Attributes

None

2.2.2 Methods

name	parameters	description
grab	()	Begin capturing keyboard events
ungrab	()	Stop capturing keyboard events

2.2.3 Callbacks

name	parameters	description
onkeypress	(keysym, code, down)	Handler for key press/release

2.3 Display Module

2.3.1 Configuration Attributes

name	type	mode	default	description
scale	float	RW	1.0	Display area scale factor 0.0 - 1.0
clipViewport	bool	RW	false	Use viewport clipping
width	int	RO		Display area width
height	int	RO		Display area height

2.3.2 Methods

name	parameters	description
viewportChangePos	(deltaX, deltaY)	Move the viewport relative to the current location
viewportChangeSize	(width, height)	Change size of the viewport
absX	(x)	Return X relative to the remote display
absY	(y)	Return Y relative to the remote display
resize	(width, height)	Set width and height
flip	(from_queue)	Update the visible canvas with the contents of the rendering canvas
pending	()	Check if there are waiting items in the render queue
flush	()	Resume processing the render queue unless it's empty
fillRect	(x, y, width, height, color, from_queue)	Draw a filled in rectangle
copyImage	(old_x, old_y, new_x, new_y, width, height, from_queue)	Copy a rectangular area
imageRect	(x, y, mime, arr)	Draw a rectangle with an image
startTile	(x, y, width, height, color)	Begin updating a tile
subTile	(tile, x, y, w, h, color)	Update a sub-rectangle within the given tile
finishTile	()	Draw the current tile to the display
blitImage	(x, y, width, height, arr, offset, from_queue)	Blit pixels (of R,G,B,A) to the display
blitRgbImage	(x, y, width, height, arr, offset, from_queue)	Blit RGB encoded image to display
blitRgbxImage	(x, y, width, height, arr, offset, from_queue)	Blit RGBX encoded image to display
drawImage	(img, x, y)	Draw image and track damage
autoscale	(containerWidth, containerHeight)	Scale the display

2.3.3 Callbacks

name	parameters	description
onflush	()	A display flush has been requested and we are now ready to resume FBU processing