Viewing This Site

The only browsers I have access to for testing purposes are Firefox and IE (Microsoft Internet Explorer). However, many of the remarks below will still be useful to users of other browsers.

Text Size & Content Width

To make the Sudoku Grids look right, you need to set the correct values for Text Size and Zoom, if your browser has these settings available.

If your browser has a Text Size setting, you should set View / Text Size = Medium or Normal.

And if your browser has a Zoom setting, you should (initially) set View / Zoom = 100% or Reset.

With those settings, the page content is probably readable. If not, there are buttons for layout adjustment.

At the top left of every page, there are two buttons <−  −> −> <− for adjusting the content width. (These will have an effect only if your screen is larger than 800 x 600 pixels.)

And at the top right are three buttons +   − for adjusting the text size: + increases the text size, − decreases it, and   resets it to the default size.

If you have cookies enabled, then any settings you make via these five buttons are stored in a cookie: if you switch to another page on this site, those settings are automatically propagated (by the cookie) to the new page. (The cookie is a session cookie, which means that it never gets written to your hard drive: it dies when you close down your browser.)

If you feel compelled to make changes to the layout, you should try out the changes on a page such as Basics where there's a Sudoku Grid visible near the top of the page. I suggest making the adjustments in the following order:

• View / Zoom In if you want the Sudoku Grids bigger (if your browser has a Zoom setting).

• Use <−  −> −> <− to set the content width so that a Grid occupies about half of that width.

• Use +   − to set the text size to suit you.

However, if you have a big screen and you prefer to use a floating resized window, you'll want the content to be full-width in that window. So you'll probably proceed as follows:

• Click <−  −> until the content fills the entire window width.

• View / Zoom In if you want the Sudoku Grids bigger.

• Drag the right edge of the window to resize it so that a Grid occupies about half the window width.

• Use +   − to set the text size to suit you.

Microsoft IE6 has a bug which prevents multi-word labels in the navigation buttons from wrapping when you use the + control, so that these labels gradually get more and more clipped as you increase the text size.  IE8 does not have this bug; neither does Firefox.

Since the CSS design of this site is fluid (not fixed), when you use View / Zoom In or windows resizing, the text will flow, and you won't be stuck with a horizontal scrollbar.

 

Javascript

To view this site, you have to have Javascript enabled. All of the example Sudoku Grids are Javascript-generated, and the navigation bar on every page is Javascript-driven.

Javascript was designed to be safe. It cannot read or write files on your system. (Javascript is not Java.)

By contrast, Java and Active-X are both powerful constructs which carry the risk of doing things to your system you don't want done.

If you do not encounter "Enable Javascript" messages when viewing this site, then skip the rest of this section.

In Firefox 1, 2, or 3, do this to enable Javascript:

• click Tools / Options;
• click Web Features (FF1) or Content (FF2 or 3);
• check Enable Javascript;
• click OK.

In IE6, 7, or 8, you can enable Javascript this way:

• click Tools / Internet Options;
• click the Security tab;
• leave Internet selected (highlighted);
• click Custom Level to get the Security Settings dialog box;
• scroll way down to Scripting / Active Scripting and check Enable (note this is not Active-X);
• click OK; click next OK.

After enabling Javascript (in either Firefox or IE), click View / Reload or View / Refresh; if that doesn't succeed in producing a (rather large) navigation bar at the top of the page, then you will be forced to write down the address of this site, completely shut down your browser, and then relaunch the browser again.

 

Cookies

As noted above, when you use the <−  −> −> <− buttons to change the content width or the +   − buttons to change the text size, a cookie is saved on your computer to record your choices. If you switch to another page on this site, that cookie is read, and the content width and text size you chose are automatically applied to the new page.

But if you have cookies disabled, the content width and the text size revert to their default values every time you switch to a different page.

(If you never use the width and text size buttons, then skip the rest of this section.)

To enable cookies in Firefox 1:

• click Tools / Options;
• click Privacy;
• click Cookies;
• check Allow sites to set cookies;
• (optionally, check For the originating site only;)
• click OK.

To enable cookies in Firefox 2 or 3:

• click Tools / Options;
• click Privacy;
• click Cookies;
• check Accept cookies from sites;
• (optionally, un-check Accept third-party cookies;)
• click OK.

To enable cookies in IE6, 7, or 8:

• click Tools / Internet Options;
• click Privacy;
• click Advanced;
• check Override automatic cookie handling;
• select First-party Cookies: Accept;
• (optionally, select Third-party Cookies: Block;)
• click OK; click next OK.

After enabling cookies (in either Firefox or IE), click View / Reload or View / Refresh so that cookie enablement will apply to the current page.

 

Printing

There are three problems with printing the pages of this site.

First, the Sudoku Grids are HTML tables, not graphics, so a printer would usually tear any Grid in half that occurred near a page break. To prevent this from happening, I inserted a CSS command to force a page break before every Grid during printout:  now the Grids won't be wrecked, but you will undoubtedly not be happy with the extra white space on the printed pages.

(I originally inserted the CSS command page-break-inside: avoid, but both IE and Firefox ignored this, with the result that the printed Grids were often torn in half.)

Second, all the Sudoku Grid examples are colour-coded via background colours in various Cells. If you have a colour printer and want the Cell background colours to appear on the printout, you have to adjust your browser settings as follows.

In Firefox, do this:

• click File / Page Setup;
• check Print Background (colors & images);
• click OK.

For IE6 and 7 do this:

• click Tools / Internet Options;
• click the Advanced tab;
• scroll down to Printing, and check Print background colors and images;
• click OK.

For IE8, do this:

• click File / Page Setup;
• check Print Background Colors and Images;
• click OK.

After you've made this setting, your browser (Firefox or IE) will now print all background colours and background images forever. If you don't want that to happen, you will have to reverse the above action after you've finished printing pages from this site.

Third and last, you have to make a number of layout settings in order to get a reasonable printed result.

Oddly, View / Zoom and window resizing don't seem to affect the printed result.

But a lot of other things do. You have already set the option for printing background colours (as indicated above). These are the remaining things you need to do:

• Verify that you have View / Text Size set to Medium or Normal (if your browser has a View / Text Size setting, that is).

• In the +   − buttons, click the gray   button to reset the text to its default size.

• Click the <−  −> button until the content takes up the full window width.

• Click File / Print Preview.

• Set the %-size to 100% or Shrink to fit.

At this point you can look through the previewed pages. They should look all right, and you can click on Print (in the upper left corner), which will give you the usual dialog box for printing.

 

Problems with IE6's Rendering of Twin Tagging

In the explanatory text on this site, Microsoft IE6 randomly leaves off the underlining on a doubly Twin-tagged digit bearing both an underline and a vertical bar; this rendering error occurs most often when you use the scroll buttons or the mouse scroll-wheel (but only in Microsoft's browser). At the places where this can happen, I have indicated that you can click View / Refresh to restore the underlining.

Fortunately, this problem does not occur inside the Sudoku Grids themselves, because they're actually HTML tables. Microsoft assigns different layout properties to table-cell contents and manages to avoid lousing up the Twin-tagging in the Grids.

According to what I've read, IE7 cured some but not all of IE6's various layout errors; I don't know whether the underline-tag problem persists in IE7 or not. (I'm unable to get a copy of that browser.)

Firefox doesn't have these problems.

 

Browsers

If you would be interested in having a browser that doesn't accept invasive Active-X content, I strongly recommend installing Firefox.
Go to

and see what they have to say.  Installing Firefox does not force you to uninstall Microsoft IE.  With both Firefox and IE installed, you can use either one you want at any time (or even both simultaneously).

I routinely use Firefox, in which I refuse to click on any "Click Here to Download Plugin" notifications, thus avoiding the plugins that produce such a plague of advertising. For IE, I accede to some plugin-installation requests; if I happen to visit a site with Firefox that actually seems to need the plugin in order to function, I copy Firefox's address bar and then open an IE window and paste the address in its bar and hit Go (thus avoiding polluting my Firefox browser with toxic software).

Have a look at Mozilla's web site.