Passing a negative angle to Arc Distortion

[javiersm]

Good Morning,

I have a doubt, I wrote this function to make a text effect:

Code: Select all

        double dargs[1] ;
        dargs[0] = -35;
        MagickDistortImage(wand, ArcDistortion, 1, dargs, MagickTrue );

The problem is when I give to the function this value (a negative one) the text is not getting distorted, is something wrong? or this function not allows negatives values in angle? Is there any other way to get the text bended in a negative angle? thanks a lot!

Best regards.

[el_supremo]

Does this do what you want?

Code: Select all

dargs[0] = 360-35;

Pete

[javiersm]

Hi,

I tried that angle too, but makes a concave form too, what I would like to generate is the opposite one, a convex one. thanks for your attention!, best regards.

[anthony]

I never designed Arc with negative angles in mind. I mean mathematically it does not make sense, though logically it does.

If you want to reverse the directon of the arc the simplist way is as given in IM examples. pre-rotate the text image so that it is upside-down, and add a 180 rotation offset argument to rotate it back as part of the Arc distort.

convert -font Candice -pointsize 20 label:' Around the World ' \
-virtual-pixel Background -background SkyBlue \
-rotate 180 -distort Arc '270 180' arc_flip.jpg