Hello, I am new to Inkscape and I want to use it to draw icons and logos for my Android apps . Currently I am working on a simple calculator image on which I applied Oil Painting effect. The document has a size of 500x500 px and the image looks just like I want .
The problem is that if I scale the image down to 72x72 px to export it as png for my app icon, the rectangle that has the filter applied goes invisible.. I have also a text over it and the text is shown and scaled properly. However, if I try to scale the rectangle without that filter on it, the scale goes fine..
I am using Inkscape 0.48.

What I am doing wrong? Can someone give me a good tutorial to learn about effects and how can I scale them correctly on Inkscape?

PS: Thank you for your great work!

Welcome to InkscapeForum!

Yeah, those filters can be SOooooo frustrating, lol. Some seem to only work on small objects, and others seem to work better on large ones. That's because most, if not all of the filters are actually raster content within the vector file. Raster means the colors are mapped to the pixels, and that's why scaling raster objects causes the phenomenon known as pixelation. That's why many people prefer vector graphics -- the scalability without distortion!

There may or may not be a way to tweak the filter to work in the situation where you need it. But first, instead of applying the filter and then scaling the object, have you tried scaling the object first, and then applying the filter? I'm guessing that will not work. But it might, and certainly not hard or time consuming to try it

Let's see.....since you included so many details in your message, I'll be able to do some experimenting. One question though -- do you have the Oil Paint filter applied to the text, or just to the calculator object?

There's a chapter in the manual on Filters. Well actually 2 chapters. Go to Help menu > Inkscape manual > Filter Effect (Preset) and (Custom). But good luck understanding the custom chapter, lol.

I'll let you know how my experiments go

Edit
Ok, I had the same experience as you. If you scale it smaller, after a certain point, the whole object just disappears! I think it has to do with the size of the object which was originally used to create the filter. However, if I scaled my sample rectangle first, and then applied the filter, it doesn't disappear. This technique does cause the effect created by the filter to appear slightly different. Maybe not even noticable difference. But if it is, you can probably tweak the filter a little to make up for it.

catalinp wrote:The document has a size of 500x500 px and the image looks just like I want

I would export at 500x500px and use a raster graphics program (such as The GIMP or Photoshop) to scale it to 72x72px. It may not give you exactly the same result, due to anti-aliasing, but it might be good enough for your needs.

Thank you both for your help , sorry for the late reply but I was in a trip .