Currently (as of HTML 3.2 and 1997 ;_) webdesigners use two commonly known
tricks for creating their layout on webpages: HTML tables and so-called 1pt
Dot-Images. The first one is nicely supported by the WML tag
"<grid>" (see wml::des::grid(3) for details), the latter is supported
by this "<imgdot>" tag.
The usual purpose of this tag is to create a transparent PNG or GIF image with a
physical size of 1x1 points and a corresponding "<img>" tag which
includes this image with appropriate "width" and "height" attributes. The
visual result is a invisible reserved space of size "width"X"height".
Alternatively this tag can create the image with the requested size instead of
scaling the 1pt image (see the "noscale" attribute below). This approach is
more safe (all browsers support this) but wastes bandwith and increases page
Usually the created images are named
imgdot-XxY-rrggbb.png where "XxY" is the dimension of the image and
"rrggbb" the used color (or `"transp"' for transparent). When you use a
"base=foo" attribute, then the resulting files are named
foo.imgdot-XxY-rrggbb.gif. Actually you can even use a complete filename
including a directory prefix, i.e. when you use "base=../../common/foo"
attribute, then the PNG images are created as
And for most flexibility when no base is specified and the variable
"IMGDOT_BASE" is defined (usually from within a .wmlrc file via
"-DIMGDOT_BASE~path/to/imgdot/dir/base") it is used. Use this feature to
redirect the created images to a particular directory.
You may also use the variable "IMAGE_BASE" which defines in a single line
all base names for images generated by WML.
By default, GIF images are generated. This attribute lets you use an
alternate image format (actually only PNG and GIF are recognized).
You may also change the default format with the variable "IMAGE_FORMAT".
Specifies the width (x-dimension) of the reserved space in pixel. Default is
Specifies the height (y-dimension) of the reserved space in pixel. Default is
Sets the color of the image. Default is transparent, i.e. no color. In
fact, this is not true, transparency is rendered by choosing a color
which is made transparent, which is white by default.
Prepending an hyphen to the "color" attribute sets the color of the
Sets the alignment of the image. Default is `"bottom"'. This alignment is
used for the "align" attribute of the inserted "<img>" tag.
Indicates if the image should be created with 1pt in size and scaled online by
the browser (default) or should be created with the correct physical size
The ``ATTR=STR'' pairs are passed along to the "<img>" HTML tag.