Negative Ink - Suggestion for a new option

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frozenknight
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Joined: Fri Dec 10, 2010 11:43 pm

Negative Ink - Suggestion for a new option

Postby frozenknight » Sat Dec 11, 2010 12:00 am

OK, I really don't want to sound dumb or anything, and so if this option can be done already in inkscape I'd like it if someone would teach me how to create it.

I like doing maps in isometric (axonometric) perspective in inkscape, you know like the view used in various elder games such as a big part of the Tycoon games, AoE... and the like. This maps are just fantasy and aren't really meant to be produced in some way...
Anyway, more to the point I sometimes make annotations in a different layer (jot down positions and markins like: "player should start here"). I mostly do it with a contrasting color than the background, to make sure I see them when I activate the layer.

The PROBLEM: It's no big deal changing colors everytime so they don't mix with the background, but it would be a nice thing if there was a way to make a filter or a color button that said negative.
and everywhere the ink would be it would show the complementary color for that pixel example:


0xFF0000, 0xFF8000, 0xFFFF00 would look like 0x00FFFF, 0x007FFF, 0x0000FF

So the calculation would be 0x1000000 - color, or better 0xFFFFFF XOR color.

It would really be cool in my opinion :)

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prkos
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Re: Negative Ink - Suggestion for a new option

Postby prkos » Sat Dec 11, 2010 12:17 pm

Check out the negative filter, http://www.openclipart.org/detail/17135

Why the large font in your post?
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druban
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Re: Negative Ink - Suggestion for a new option

Postby druban » Sun Dec 12, 2010 2:23 am

I agree, this would be nice to have as a layer blend mode, a la "difference" mode in raster programs, which is not a mode we have at present in Inkscape. Of course Filter effects can handle it, but integration into layers would be better.
Your mind is what you think it is.

ivan louette
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Joined: Thu Aug 21, 2008 4:08 am
Location: Belgium

Re: Negative Ink - Suggestion for a new option

Postby ivan louette » Sun Dec 12, 2010 6:44 am

You can assign any filter to a layer.

- draw an object
- apply to this object the filter you want to apply to your layer (for example the filter Color/Invert)
- open the Filters Editor
- open the Layer Editor and change the layer Blend mode from Normal to any other one ; you will see that a new filter appears in the Filters Editor
- open the XML Editor
- click on the svg:defs line on top of the tree ; it will unwrap and show a line with the filters
- take a look at the id number of the Invert filter (id="filter....")
- click on the line svg:g id= on the bottom of the tree
- click on style in the window on the right
- change the number in the bottom window in filter:url(#filter....) to the number of the Invert filter

Everything you draw in your layer is now negative.

And you can do that with any filter ; this is a very powerful feature !

ivan

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druban
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Re: Negative Ink - Suggestion for a new option

Postby druban » Sun Dec 12, 2010 3:10 pm

Thanks for the explanation, Mr. Louette. This is indeed as easy - if not easier - as selecting 'difference' and 'multiply' from a drop down menu in the layers dialog!
Your mind is what you think it is.

ivan louette
Posts: 215
Joined: Thu Aug 21, 2008 4:08 am
Location: Belgium

Re: Negative Ink - Suggestion for a new option

Postby ivan louette » Sun Dec 12, 2010 8:54 pm

druban wrote:Thanks for the explanation, Mr. Louette. This is indeed as easy - if not easier - as selecting 'difference' and 'multiply' from a drop down menu in the layers dialog!


Of course every filter in the document should be available from the Layers drop down list !

ivan

frozenknight
Posts: 2
Joined: Fri Dec 10, 2010 11:43 pm

Re: Negative Ink - Suggestion for a new option

Postby frozenknight » Mon Dec 13, 2010 10:11 pm

@prkos: I made some of the text larger to show that that is indeed the core of the problem and a important part, should I have made the post too lengthy/boring. So that part would stand out. If it's disturbing I can edit it back :D.

@ivan louette: Thank you for your post. That is indeed a simpler way of getting the negative of everything I post in there :).

But the thing I actually wanted to accomplish is something like this:
Image

Now it would be awesome the center negative region were a path with a negative stroke-paint. I know that that's not possible, but I would love if everything I draw in the "Negative layer" would shape the negative region of the lower layers.

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RobA
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Joined: Fri Aug 10, 2007 1:22 am

Re: Negative Ink - Suggestion for a new option

Postby RobA » Tue Dec 14, 2010 3:14 am

frozenknight wrote:I like doing maps in isometric (axonometric) perspective in inkscape, you know like the view used in various elder games such as a big part of the Tycoon games, AoE... and the like. This maps are just fantasy and aren't really meant to be produced in some way...


Hi-

Come over to www.cartographersguild.com and join the forum to share some of those maps!

-Rob A>


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