| << Chapter < Page | Chapter >> Page > |
The purpose of these parameters is to provide compatibility with the speaking capability of the IVEO viewer .
If the output SVG file is opened in the IVEO viewer , the title for the svg element is spoken when the user opens the file.
The titles for the individual shapes are spoken by the IVEO viewer when the user touches a corresponding shape on the touchpad or clicks on thatshape on the screen.
If the SVG file won't be used with the IVEO viewer , just leave the title strings unchanged. If the SVG file will be used with thethe IVEO viewer , you can modify those strings to cause the viewer to speak whatever titles you choose. (Don't remove the quotation marks if you modify the title string.)
You can read more about this capability under The SVG graphics library .
SVG code to create a canvas
If you were to delete all of the remaining code in Listing 25 down to but not including the statement that writes the output SVG file, the resulting SVG codewould be that shown in Listing 4 .
| Listing 4 . SVG code to create a canvas. |
|---|
<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"><svg xmlns="http://www.w3.org/2000/svg" version="1.1"
width="990" height="765"><title>Document Title</title> |
The width and the height of the canvas
The first three lines of text in Listing 4 constitute housekeeping information that you needn't worry about. It will always be the same.
The fourth and fifth lines of text in Listing 4 define the width and height of the canvas.
As you can see, the width is set to a value of 990 and the height is set to a value of 765.
The last line of text in Listing 4 is the title element discussed earlier .
SVG units
SVG doesn't inherently deal with dimensions in inches (although it is possible to specify inches when you define the value for a size attribute.) . Instead, it deals with dimensions in something that I will refer to as "SVG units", and for reasons that I am unable to explain, there appear to be 90 SVG units per inch or 35.43SVG units per centimeter.
Thus, a width of 990 (as shown in Listing 4 ) corresponds to a width of 11 inches and a height of 765 corresponds to a height of 8.5 inches.
If you elect to write raw SVG code for you drawings, you will need to think in terms of SVG units instead of inches (or write all of the size attribute values something like "8.5in") . However, I designed my SVG graphics library so that you can think in terms of inches instead of SVG units without having toremember to specify the units for every size value.
The Java code in Listing 5 draws a rectangular border on the canvas by creating an SVG element of type rect (for rectangle) .
| Listing 5 . Draw a rectangular border on the canvas. |
|---|
//Draw a rectangular border on the canvas.
Element border = SvgLib21.makeRect(svg,ns,
"rectangle",//title0.015,/lower-left x-coordinate in inches
0.015,//lower-left y-coordinate in inches10.97,//width in inches
8.47 //height in inches); |
Notification Switch
Would you like to follow the 'Accessible physics concepts for blind students' conversation and receive update notifications?
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|