Reproducing steps in custom plugin

[dopestuff]

Hi. I'm trying to write my first plugin that reproduces the steps in this video:

 

I have everything set up in Visual Studio, the plugin loads fine and so far everything's good. But I'm not sure where to begin. My OnRender() sub is empty. I don't know where to look for documentation on the effect class.

Could somebody give me a push in the right direction or tell me what functions I need to call do to what. I would appreciate it a lot.

[BoltBait]

You should probably start by reading this series of tutorials:

http://www.BoltBait.com/pdn/CodeLab/Help

[Red ochre]

There is already a chromatic (color) aberation plugin - here

http://forums.getpaint.net/index.php?/topic/19513-color-aberation-ymd100726/

 

Just thought I'd mention it ... I highly recommend writing your own plugins though!

[MJW]

Sometimes it's not easy to find the functions you need. For what you want to do, you should know about src.GetBilinearSample(x, y), src.GetBilinearSampleClamped(x, y), and src.GetBilinearSampleWrapped(x, y).  "src" is the source surface. It could be a different surface, but src is the one you'll probably use. "x" and "y" are floating point numbers representing the image coordinates of the point you want to fetch. "Clamped" and "Wrapped" refer to how coordinates outside the image range are handled. For each color channel, you'll need to add float offsets (converted from input-variable doubles) to float versions of the image x and y coordinates (the for loop variables), then get the pixel, as a ColorBgra.

 

If you only want to allow integer shifts, then you can directly index into the src surface. This has the advantage of avoiding blurring caused by bilinear interpolation at non-integer shifts, but the disadvantage of allowing only integer shifts. Normally, there's little reason to use the slower GetBilinearSample calls if the coordinate arguments only take integer values.

Edited June 19, 2015 by MJW