The aim of this project is to provide a fast and lightweight library that helps to display online panorama scene. Pano.js is based upon Javascript and HTML5 technology. It uses WebGL for efficient hardware accelerated display. For older browsers where WebGL is not available, a canvas 2D rendering backend will be enabled as a fallback.
Pano.js can be easily integrated into online applications. The simplest usage only requires a single line:
var view = new Pano.View( canvas_tag, { equirectangular: 'my_panorama.jpg' } );which creates an instance of Pano.View, and then loads a panorama image and displays it on a given canvas element.
The library exposes only a single class Pano.View whose interface is kept as explicit as possible for use.
Pano.View(canvas, options)
Constructor to create a new instance of Pano.View on a given canvas with optional parameters.
canvas- A canvas element on which to create the view instance.options- A wrapper object holding a series of optional parameters, including:heading- The initial heading angle of the view. Default to 90.pitch- The initial pitch angle of the view. Default to 90.fov- The initial field of view angle. Default to 90.rendering- Suggests the rendering method to use. This can be 'webgl' or 'software'. Default to 'webgl' if WebGL is available on the browser.inertial- Set this to 'on' or 'off' to turn on/off inertial move. Default to 'on'.filtering- Whether and when to activate filtering to gain better image quality. This can be 'on', 'off' or 'on-idle'. Default to 'on-idle'.equirectangular- The URL of the panorama image to load. Default to empty string.
After Pano.View has been instantiated, the following method can be involked on it to manipulate the panorama and the view.
view.load(url, reset)
Set the URL of a new panarama image that will be loaded in.
url- The URL of the panorama image to load.reset- Whether to reinitialize the view when the new panorama image is loaded and applied. Default to false.
view.reset()
Reset the view to its initial state. If it is in navigation mode, the navigation will be cancelled immediately.
view.yaw(degs)
Rotate the view a given angle along the horizontal axis.
degs- Degrees to rotate.
view.pitch(degs)
Rotate the view a given angle along the vertical axis.
degs- Degrees to rotate.
view.zoom(degs)
Zoom in/out the view by changing the field of view a given degrees.
degs- Degrees to zoom in/out.
view.jumpTo(heading, pitch, fov)
Move the view to be aiming at a new position with new zoom factor given by the heading and pitch angles and the fov value. The change is applied immediately without approaching animation.
heading- The heading angle in degrees to jump to. Default to current angle.pitch- The pitch angle in degrees to jump to. Default to current angle.fov- The fov angle in degrees to jump to, which specifies the zoom factor. Default to current angle.
view.navigateTo(heading, pitch, fov, duration, callbackOnArrival, easingFn)
Similar to jumpTo except that it starts a navigation to the new position and zoom factor using animation.
heading- The heading angle in degrees to navigate to. Default to current angle.pitch- The pitch angle in degrees to navigate to. Default to current angle.fov- The fov angle in degrees to navigate to. Default to current angle.duration- Time length in milliseconds after which the target position is reached. Default to 2000.callbackOnArrival- A function that will be invoked at the end of the navigation. Default to null.easingFn- Specifies the interpolation method used to smooth the animation. Default to 'Quadratic.InOut'.
view.playTour(path)
Start a tour along the path defined by a given series of nodes.
path- An array which contains a series of nodes defining the path of the tour. Each node should be an object specifying the node's position and an optional action:heading- The heading angle in degrees that specifies the position of the node.pitch- The pitch angle in degrees that specifies the position of the node.fov- The fov angle in degrees that specifies the zoom factor on the node.duration- Time length in milliseconds of the animation between the node and the next node.hoverTime- Time length in milliseconds to hover on the node.onArrival- A function that will be called when the node is reached.
On implementation level, navigateTo is used to navigate between each node.
view.addLabel(innertHTML, heading, pitch, isInteractive, frameOptions, callbackOnLayout)
Add a label on a given position of the panorama.
innerHTML- Content of the label. It can either be a plain text or a segment of HTML enclosed by tags. This feature enables design of complicated labels.heading- The heading angle in degrees which specifies where the label should be placed.pitch- The pitch angle in degrees that specifies where the label should be placed.isInteractive- Whether the label is interactive.frameOptions- An object providing parameters to customize the frame of the label:width- The width of the whole label in pixels. Default to '200px'.textAlign- The text align style of the content. Default to 'left'.borderWidth- The width of the frame border in pixels. Default to '3px'.borderColor- The color of the frame border. Default to '#5a8f00'.foregroundColor- The color to render the content of the label. Default to '#333'.backgroundColor- The color used to fill the background of the label. Default to '#fff'.
callbackOnLayout- (todo)
An example of labeling can be found here.
view.addLensFlare(flareImgURLs, heading, pitch, range, scales)
Add a group of lens flare effect on a given position of the panorama.
flareImgURLs- An array containing the URLs of a group of circle/ring images which will be used for the flare.heading- The heading angle in degrees that specifies the position of the light source, where the flare starts.pitch- The pitch angle in degrees that specifies the position of the light source.range- This number influnces the distribution of circles/rings along the axis of the flare.scales- An array of factors which will be used to scale the circle/ring images to appropriate sizes to display.
An example of adding lens flares can be found here.
view.eulerToView(heading, pitch)
Utility method. Given a position by the heading and pitch angles, it returns the (x, y) coordinates on the canvas.
heading- The heading angle in degrees.pitch- The pitch angle in degrees.
view.viewToEuler(x, y)
Utility method. Given the coordinates on the canvas, it returns the equivelant heading and pitch angles.
x- X coordinate on canvas in pixels.y- Y coordinate on canvas in pixels.
view.maximize()
Resize the view/canvas to fill the client area of the browser.
view.restore()
Restore the view/canvas to original position and size before last call of maximize.
An example that demonstrates the usage of maximize and restore can be found here.
view.saveScreenshot(basename, format, quality)
Take a screenshot of the view and save it as an image file with the given name, format and expected quality.
basename- File name of the result. Default to 'screenshot'.format- Image format to save as. This can be 'jpeg', 'png', or 'gif'. Default to 'jpeg'.quality- Expected quality if the specified format uses lossy compression. Default to 0.8.