In this thread I try to explain how to do a simple car graphic. Sorry that all in images is in Polish but I'm Polish and I work in polish version of GIMP 2,8. I translate what is necessary in every step, so don't worry
Part of the things you have to deduce but I am sure that you can do it.
1. You have to have a images of car, which you wanna have
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For Examples : I use in this case a SWAT bearcat which I found on wikipedia (https://pl.wikipedia.org/wiki/Niewojsko…ash_Bearcat.jpg)
2. Add alfa
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with right mouse button clik and choose alfa canal or in second way
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3. Cutting background
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with left button we mark the area, to end click to the first point.
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now click right button edition and cut.
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more more more
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and done with this step.
4. Reduction
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image -> scaling
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this mark should be close
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choose the height (I use 60 or 40 px) and scaling
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done.
5. Save
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file -> export as
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name with .png ( it is really important to have Transparent Background) and export
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and export.
6. emergency lights
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you can increase picture by "magnifying glass" or shift/ctrl with a roll of the mouse( This does not change the main image size )
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add new channel (right mouse button)
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transparent and OK
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new chanel move down and choose with lef mouse button
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1. brush , 2. choose color 3. brush options, e.g., size etc.
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now choose a pictures channel and use a lasso. TIP you can mark more area when you use a shift
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fill marked areas with this( you can choose a little lighter color)
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Save as previously
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DONE!
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I hope that I helped
PS. Merry Christmas and happy new year