Simple Drop Shadows by SpaceRay

Simple Drop Shadows by SpaceRay
http://www.filterforge.com/filters/11571.html

I have had this snippet since long time ago and I have decided to submit it to the library for anyone that wants to add a drop shadow to any of your filters, you can do it with this one, although for now you can´t change the shadow direction

This shown in this thread below is an example of what can be done with this

Fractals by bomber

This without drop shadow



With added drop shadow



I think it looks much better and let´s separate the layers and does not look all glued and plain as the one without drop shadow

Couple notes: even if you set the levels with gamma set at -100 there's a good chance colors (or luminance values) will leak through with various situations. The point is, that's just how the levels component works.

In the current method, you're using the difference blend mode to combine two images together. Difference mode should be reserved for intentionally inverting parts of the image based on another (or seeing differences between two similar images). In this case, you got two big blobs of shadows being combined, in such cases, multiply blend mode works best. The reason why you're seeing problems when you use the get-alpha component is because you're using the difference blend mode. It's just behaving as it should.

Ah.... this is one of those filters where the construction itself forces you to use weird methods. I see what you did and the reason why you used the screen blend. It works, but it's technically not so clean.

Consider this: the screen blend is a dodge blend mode, meaning it's got brightening properties. Now in this case, you don't see that because you got a black shadow and alpha background. So if there's a situation where somebody wants to change the color of the shadow, then the screen blend at the end of the chain will affect the end result. Which is why I see it as a round-about way of creating the shadow amount parameter.

Typically the color image goes on top of the shadow layer, therefore using the Normal blend mode will suffice. However, because you want the "amount" parameter, this doesn't work. A simple, not-so-elegant solution is to simply place something that allows the user to alter colors, change alpha properties of the shadow, but this is like dealing with it "after the fact that shadows have been derived." So some of these factors do have to be "built-in" to the structure.

(Below) Here's a version I was constructing. Keeping in mind some of the parameters you set up, I tried to build it around what you were trying to accomplish.

New update already available in the Library

-------------------------------------------

Thanks very much for making an alternative and better way to make drop shadows and it looks well, will try it later.

Thanks for uploading it here, but I think that you could upload it to the library as a snippet too as it your own filter and whole creation.