wml::des::imgdot - 1pt Dot-Images for Webdesign

 #use wml::des::imgdot

 <: $file = &imgdot($base, $x, $y, $c, $r, $g, $b, $transp, $format); :>

 <imgdot [attributes]>

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 CW<grid> (see wml::des::grid(3) for details), the latter is supported by this CW<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 CW<img> tag which includes this image with appropriate CWwidth and CWheight attributes. The visual result is a invisible reserved space of size CWwidthXCWheight. Alternatively this tag can create the image with the requested size instead of scaling the 1pt image (see the CWnoscale attribute below). This approach is more safe (all browsers support this) but wastes bandwith and increases page load time.

base

Usually the created images are named imgdot-XxY-rrggbb.png where CWXxY is the dimension of the image and CWrrggbb the used color (or `CWtransp' for transparent). When you use a CWbase=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 CWbase=../../common/foo attribute, then the PNG images are created as ../../common/foo.imgdot-XxY-rrggbb.png. And for most flexibility when no base is specified and the variable CWIMGDOT_BASE is defined (usually from within a .wmlrc file via CW-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 CWIMAGE_BASE which defines in a single line all base names for images generated by WML.

format

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 CWIMAGE_FORMAT.

width

Specifies the width (x-dimension) of the reserved space in pixel. Default is 1 pixel.

height

Specifies the height (y-dimension) of the reserved space in pixel. Default is 1 pixel.

color

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 CWcolor attribute sets the color of the transparent color.

align

Sets the alignment of the image. Default is `CWbottom'. This alignment is used for the CWalign attribute of the inserted CW<img> tag.

noscale

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 (this option).

:img:ATTR=STR

The ``ATTR=STR'' pairs are passed along to the CW<img> HTML tag.

 Ralf S. Engelschall
 rse@engelschall.com
 www.engelschall.com

 Denis Barbier
 barbier@engelschall.com

 Internal: P1, P2, P3

HTML <CWimg> tag.