On Sunday 06 May 2007, Bosse Arnholm wrote:
> Hi,
> I parently work on PGS 4.1.2.
> I have an A4 document with a photografic picture covering the ful page and
> I wnat to have a transparant .gif-logo on top of that.
> The logo is transparant but not when I've mounted it on the page.
> If I apply a mask, parts of the .gif becomes transparant, but not all of
> it.
It has been a while since I've worked with gif files in PgS so I could be
wrong, but I don't believe PgS uses the transparency information in a gif.
On to masking:
Did you use the PgS function to generate a mask? If so, here's a description
of how that works: it picks a color as the background color. I *think* this
is the color of the top-left corner pixel, but I'm not certain. For each
pixel row PgS reads from the left (and the right) until it finds a
non-background color pixel -- that marks the edge of the mask for that pixel
row. Although the mask can have a funky shape it will be continuous -- that
means there cannot be any holes so if you have a picture of a donut against a
neutral background it will mask out the *edges* of the background, but the
part of the background visible through the hole of the donut will *not* be
masked out.
It also means that the edging is *only* left-to-right, *not* top-to-bottom.
For example, if you take a picture of a human figure standing with arms
spread slightly from the sides and legs spread slightly, all against a
neutral background, the mask will go down the left arm to the tip of the
finger and then continue down the leg. It *won't* go up the inside of the
left arm to the armpit and down the left side.
It has been too long since I've worked with images that had "holes" to
remember if you can manually mask "donut" holes or not, but the second kind
of "hole" can be definitely be manually masked.
Basically, PgS's automatically generated mask is suitable for text wrapping,
not graphic composition. If you have a picture of a donut that text is being
wrapped around you don't normally want text to appear in the middle.
How to create your own masks? Any continuous vector drawing can be used.
Continuous means you can put the mouse cursor over any part of the line,
follow the line with the mouse cursor, never leave the line, and you will
eventually get back to where you started. There can be no "skips" or separate
pieces. You use the menu it "Apply Mask" with both the vector drawing and the
graphic selected.
Using the drawing tools in PgS it is fairly easy (though time consuming for
large, detailed graphics) to manually create a mask. To speed things up you
can have PgS generate a mask, release it (using the menu), and then edit it.
Tim Doty
.
arnholm.
