Changing colors: what do I do wrong?

[FilipV]

Hello,

I'm new at using GIMP, so probably the answer is easy, but I can't find out what I do wrong. who can help me?

Attached a xcf file with a world map. I would like to change the color of South America to blue.

I have selected South America with
Tools - selection - oval  (remark: I use a Dutch language version, so maybe some translations aren't accurate)

Then
right clic - colors - tint/saturation

In the pop-up screen I select "Green"
and move the 'tint' indicator to value 130.  In this pop-up, the color next to "G" indeed turns blue.

Finally I press OK, and expect South America to become blue, but nothing happens. What goes wrong?

Who can shine light in my darkness?  Thanks already.

Filip

[Espermaschine]

Are you sure you have the map layer selected ? Because in your xcf file, there is also a transparent layer, which is active.
Make sure you leftclick on the map layer, so that it is selected, before you apply Hue/Saturation.

[Blighty]

As Espermaschine said you probably had the wrong layer selected.

In Gimp there is usually more than one way to achieve something. Here is another method.

1. Select South America. Use the Free Select tool and keep your selection out in the white sea.

2. Select the Select By Colour tool. In the tool options set the Mode to Intersect With Current Selection - the 4th option

3. Click on the green inside South Amerca. The green in South America is selected, the white lines are excluded.

4. Set the foreground colour to the blue that you want.

5. Bucket fill the selection with blue.

[rich2005]

That image started off as a vector (svg) graphic so the best way would be a vector editor such as inkscape
However
Yet another way using Gimp and this only works because the background is white.

Make a rough selection http://imgur.com/9l2HIdr.jpg

Fill that selection - top transparent layer - with blue http://imgur.com/8QPinwQ.jpg

Change the layer mode to screen. http://imgur.com/CwKf4mt.jpg

This avoids having to mess with the thin border of semi-transparent green pixels left over from a color selection.
But there might be other reasons, a distinct shape of South America, is needed in which back to previous method.

[Ofnuts]

Completely different method, using a script of mine, since you have paths:

1) In the Paths dialog, make all paths visible (shift-click the eye icon on any of them), and then "Merge visible paths" (you end up with one single path)
2) The the freehand selection to make a rough selection around South America
3) In the Path list, right click the path, and go to Edit>Extract strokes. You will get a path restricted to South America
4) Then Select>From path and bucket-fill

Step 3) assume you installed ofn-path-edits from here

PS to the usual suspects: this particular used uncovered a bug, the just-uploaded SourceForge version is fixed.

[FilipV]

Thank you all for the suggestions: I'm going to look into it and reply

[FilipV]

Thank you all for the different answers.  It is already clear to me there are several ways to reach Rome in GIMP.
I managed to get the color to be changed, but in all honesty, I didn't really know how I did it.
I suppose I need some serious  (class room - I'm old fashioned) tuition what GIMP is concerned.  I keep on trying.

Cheerio!

[Espermaschine]

(12-04-2016, 10:02 AM)Ofnuts Wrote: I managed to get the color to be changed, but in all honesty, I didn't really know how I did it.

In a nutshell:
the effect is applied to a layer, and you hadnt selected the correct layer.
You selected the transparent layer on top of your map and obviously a layer with nothing in it, cant have a color change.

[Ofnuts]

(12-12-2016, 08:30 PM)Espermaschine Wrote:

(12-04-2016, 10:02 AM)Ofnuts Wrote: I managed to get the color to be changed, but in all honesty, I didn't really know how I did it.

No, I didn't