View images in web browser with SVG support
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1. JavaScript UI control for image viewing in web browser with SVG support
The Vintasoft.Imaging.UI.WebImageViewerJS class is a JavaScript control for viewing images in any SVG compatible web browser. The class can be created on a client-side of web application. The class requires a web service for getting information about image and rendering an image. As the web service can be used ASP.NET Core Web API controller (ASP.NET Core), ASP.NET Web API 2 controller (ASP.NET MVC 5), HTTP handler or any other .NET compatible web service.Tutorial, which describes how to embed the SVG image viewer into an ASP.NET application can be found here:
Vintasoft.Imaging.UI.WebImageViewerJS can work separately and in this case:
- Vintasoft.Imaging.UI.WebImageViewerJS creates its own image collection
- the associated image collection can be accessed via Vintasoft.Imaging.UI.WebImageViewerJS.get_Images function
- the image collection can be navigated via Vintasoft.Imaging.UI.WebImageViewerJS.get_FocusedIndex and Vintasoft.Imaging.UI.WebImageViewerJS.set_FocusedIndex functions
- image will be added to the image viewer if the image is added to the associated image collection; image will be removed from image viewer if the image is removed from the associated image collection
- the link between viewers can be set via Vintasoft.Imaging.UI.WebImageViewerJS.set_MasterViewer function of slave viewer
- the slave viewer uses image collection of the master viewer
- the shared image collection can be accessed via Vintasoft.Imaging.UI.WebImageViewerJS.get_Images function of master or slave viewer
- the image collection can be navigated via Vintasoft.Imaging.UI.WebImageViewerJS.get_FocusedIndex and Vintasoft.Imaging.UI.WebImageViewerJS.set_FocusedIndex functions of master or slave viewer
- the focused index in master and slave viewers is changed synchronously
- image will be added to the image viewer if the image is added to the associated image collection; image will be removed from image viewer if the image is removed from the associated image collection
// create images
var imageSource = new Vintasoft.Shared.WebImageSourceJS("/Images/SourceImage.pdf");
var image1 = new Vintasoft.Shared.WebImageJS(imageSource, 0);
var image2 = new Vintasoft.Shared.WebImageJS(imageSource, 1);
// create an image viewer
var imageViewer1 = new Vintasoft.Imaging.UI.WebImageViewerJS("WebImageViewer1");
// get an image collection of image viewer
var images = imageViewer1.get_Images();
// add images to the image collection
images.addRange([image1, image2]);
// set focus to the last image in image collection
imageViewer1.set_FocusedIndex(images.get_Count() - 1);
1.1. Preview of images
1.1.1. Image viewer display mode
Vintasoft.Imaging.UI.WebImageViewerJS can display one or several images simulateously.The Vintasoft.Imaging.UI.WebImageViewerJS.set_DisplayMode function allows to set one of the predefined display modes:
- Single page - the image viewer simultaneously displays 1 image.
- Single continuous column - the image viewer simultaneously displays all images in 1 continuous column.
- Single continuous row - the image viewer simultaneously displays all images in 1 continuous row.
- Two columns - the image viewer simultaneously displays 2 images in 2 columns.
- Two rows - the image viewer simultaneously displays 2 images in 2 rows.
- Two continuous columns - the image viewer simultaneously displays all images in 2 continuous columns.
- Two continuous rows - the image viewer simultaneously displays all images in 2 continuous rows.
- Three columns - the image viewer simultaneously displays 3 images in 3 columns.
- Three rows - the image viewer simultaneously displays 3 images in 3 rows.
- Three continuous columns - the image viewer simultaneously displays all images in 3 continuous columns.
- Three continuous rows - the image viewer simultaneously displays all images in 3 continuous rows.
Also Vintasoft.Imaging.UI.WebImageViewerJS allows to define the custom image display mode using the following functions:
- Vintasoft.Imaging.UI.WebImageViewerJS.set_MultipageDisplayMode - Gets or sets the multipage display mode.
- Vintasoft.Imaging.UI.WebImageViewerJS.set_MultipageDisplayRowCount - Gets or sets the count of displayed images in row or column in multipage display mode.
- Vintasoft.Imaging.UI.WebImageViewerJS.set_MultipageDisplayLayoutDirection - Gets or sets the images layout direction in multipage display mode.
1.1.2. Image preview modes
Vintasoft.Imaging.UI.WebImageViewerJS can preview image in different modes.The Vintasoft.Imaging.UI.WebImageViewerJS.set_ImageSizeMode function allows to set one of the predefined preview modes:
- Normal - previews image using the image resolution without scaling
- PixelToPixel - previews image using the screen resolution without scaling, the image resolution is ignored
- FitToWidth - scales the image to fit the width of control
- FitToHeight - scales the image to fit the height of control
- BestFit - scales the image proportion to the control
- Zoom - zooms the image to the specified value
1.1.3. Image appearance
Vintasoft.Imaging.UI.WebImageViewerJS allows to specify the appearance (background brush, background color, border color, border width, border style) for focused image using the Vintasoft.Imaging.UI.WebImageViewerJS.set_FocusedImageAppearance function and for not focused images using the Vintasoft.Imaging.UI.WebImageViewerJS.set_ImageAppearance function.1.1.4. Rendering settings
Vector images/documents, for example PDF documents, must be rendered before preview in the Vintasoft.Imaging.UI.WebImageViewerJS.Rendering settings for vector images/documents can be set with the Vintasoft.Imaging.UI.WebImageViewerJS.set_RenderingSettings function.
1.1.5. Rotation of image
The Vintasoft.Imaging.UI.WebImageViewerJS.set_ImageRotationAngle function allows to set an orthogonal rotation angle of image in the image viewer.1.1.6. Caching images on the server
The Vintasoft.Imaging.UI.WebImageViewerJS.set_UseCache function allows to specify whether caching of the image tiles on server is necessary.If web viewer uses cache:
- Web API will render image tile on server side and save image tile on server in folder "<WebApplicationPath>\VintasoftCache\<SessionId>\Tiles\".
- Web API will send URL to rendered image tile to the web viewer.
- Web viewer will receive URL to image tile from Web API, web browser will download image from URL into browser cache and display image to the user.
- Rendered image tile will be stored on client computer until browser cache will not be cleared.
- Rendered image tile will be stored on server until web application cache (folder "<WebApplicationPath>\VintasoftCache\<SessionId>\Tiles\") will not be cleared.
If web viewer does not use cache:
- Web API will render image tile on server side and send image as base64 string to the web browser. Rendered image will NOT be saved on server.
- Web viewer will receive rendered image as base64 string from server, web browser will display image to the user.
- Rendered image will be destroyed when user closed web browser.
Web application, which uses cache on server, uses image tile from cache if image tile was rendered earlier. Web application, which does not use cache on server, always re-render image tile. Web application, which uses cache, in most cases works faster than web application, which does not use cache.
1.2. Context menu of image viewer
Vintasoft.Imaging.UI.WebImageViewerJS.get_ContextMenuFunc allows to get the handler for "contextmenu" event of the viewer.Vintasoft.Imaging.UI.WebImageViewerJS.set_ContextMenuFunc allows to set the handler for "contextmenu" event of the viewer.
1.3. Visual tools
The visual tools complement functionality of Vintasoft.Imaging.UI.WebImageViewerJS class and allow to process images visually.The active visual tool of the Vintasoft.Imaging.UI.WebImageViewerJS can be set using Vintasoft.Imaging.UI.WebImageViewerJS.set_VisualTool function.
More detailed information about visual tools can be found here: "Visual tools for SVG image viewer."
2. Web Document Viewer UI for image viewing in web browser with SVG support
Web Document Viewer UI always has image/annotation viewer.WebUiImageViewerPanelJS class represents a web UI panel that can be used in web document viewer and allows to display an image viewer.
Panel will create HTML5 image viewer if Vintasoft.Imaging.DocumentViewer.js file is used together with Vintasoft.Imaging.Html5.js file and if "annotations" flag is NOT enabled in web document viewer settings.
Panel will create SVG image viewer if Vintasoft.Imaging.DocumentViewer.js file is used together with Vintasoft.Imaging.Svg.js file and if "annotations" flag is NOT enabled in web document viewer settings.
Panel will create HTML5 annotation viewer if Vintasoft.Imaging.DocumentViewer.js file is used together with Vintasoft.Imaging.Html5.js and Vintasoft.Imaging.Annotation.Html5.js files and if "annotations" flag is enabled in web document viewer settings.
Panel will create SVG annotation viewer if Vintasoft.Imaging.DocumentViewer.js file is used together with Vintasoft.Imaging.Svg.js and Vintasoft.Imaging.Annotation.Svg.js files and if "annotations" flag is enabled in web document viewer settings.
Here is screenshot of image viewer panel in web application:
