I have an alpha mask layer which I want to add several radial gradient fills. The problem is that I want it to work with an open image, so I can't use specific x1 y1 x2 y2 coordinates (images will vary in size). I'm thinking I need to use percentages. Is this possible? Am I going down the wrong road?

Any input is greatly appreciated.

Thanks.

I think your approach is right, you'll have to use ratios. Do yourself a sketch of where you want the gradient fills to be, the lengths of the height and width of the image on your sketch will be 1. The x1 y1 y1 y2 of each fill on your sketch will be some ratio of 1, say x1=0,y1=0 to x2=0.5,y2=0.5 for a gradient fill in the lower left quadrant of the image.

In your code read the height and width of the image* that has been loaded then multiply these by the ratios you've worked out for each gradient fill to give you the x1 y1 x2 y2 coordinates you need.

*Check out gimp-image-width and gimp-image-height in the PDB.

*Edit - removed obvious errors

Sorry, I'm not even qualified to be a white belt in Script-Fu. Just started using Script-Fu last week. I've never coded before now.

I think I've figured out the basics, but couldn't find in the forums or in other peoples scripts how to code the specific area I want to gradient file.

So, remembering I'm a newbie (I'll even take the hit noob, because I desperately want to learn Script-Fu), this is all I've been able to put together. The following isn't meant to be perfectly structured, because I don't know the structure:
(define *
(let*
(
(set! x (car (gimp-image-width image)))
(set! y (car (gimp-image-height image)))
(x1)
(x2)
(y1)
(y2)
;(leaving out irrelevant definitions)

)

;leaving out all irrelevant procedures

;Some gradient procedures which I'm really not certain about or how to properly order them (hope I used the word "procedures" correctly).

; now the math
;i.e. x1 = .5x * w
;or as I understand it:

;Starting position

(set! x1 (car (* 0.5 x)))
(set! y1 (car (* 0.5 h)))

;I'm fairly certain this will place my starting position in the center of the image?

;Ending position

(set! x2 (car (* 0.05 x)))
(set! y2 (car (* 0.5 y)))

;I'm fairly certain this will place my ending position to the far left of the starting position ;close to the edge of the image.

)

)

Again, I have now idea how to code this and additionally I want to do several of these gradient files in a single mask layer.

Am I asking for to much help in the coding area. I'm not here to have someone code my work for me. All responses people are giving me, I'm truly using as a learning experience.

With that said, any input is gratefully appreciated.

Thank you.

You have the right idea, though there are some errors in your code examples. The following code will perform a radial gradient from the center of the image to the lower-right corner.

Thanks a lot saulgoode!

Works perfectly! Just needed to change FG-BG-RGB-MODE to FG-TRANSPARENT-MODE for multiple fills on one mask.

Just as a side note, I kept working on my original thoughts and it works (with help from your script), however your method is far more efficient in every way. I'll just post my script as reference.

(let*

(

(width (car (gimp-image-width image)))
(height (car (gimp-image-height image)))

(x1)
(x2)
(y1)
(y2)
)

(set! x1 (* 0.5 width))
(set! y1 (* 0.5 height))
(set! x2 (* 0.05 width))
(set! y2 (* 0.5 height))

(gimp-edit-blend alphaMask FG-TRANSPARENT-MODE NORMAL-MODE GRADIENT-RADIAL 100 0 REPEAT-NONE FALSE TRUE 3 0.2 TRUE x1 y1 x2 y2)

)

Thanks again!

Tag: x y coordinates multiple several radial gradient fill open image percent percentage percentages