[r153] Adjust HSL - Luminosity makes a boarder

Found this when making customisable colour for in-game items (there's items that have two different sprites connected together like "Top hair" and "Back hair", and this bug ruins the visual effect)

I'm hoping this is a simple random little bug of easyness!

Link to .capx file (required!):

dl.dropboxusercontent.com/u/7765312/C2/hslcapx.capx

Steps to reproduce:

1. Create any sort of sprite, making sure to have the standard "1 Pixel border" around the sprite.

2. Have the "Adjust HSL" WebGL effect on.

3. Adjust the Luminosity parameter.

4. Notice the object lights up like expected, but has a darkened border surrounding it

If you shrink the sprite so that it does NOT have a 1-pixel border, the outline will no longer exist (however this isn't a quick fix for sprites that are circular)

This ONLY happens to Luminosity.

Observed result:

<img src="https://dl.dropboxusercontent.com/u/7765312/C2/hsl.png" border="0" />

Expected result:

There shouldn't be a border

Browsers affected:

Chrome: yes

Node-Webkite: yes

Operating system & service pack:

Windows 7 64bit

Construct 2 version:

r153

I'm not sure what we can do about this. We've gone through a few revisions of the effect now to fix other fringing issues for another game. I don't really want to change it again since it's likely to break the other fringing situations we've already fixed.

Feel free to hack away at the effect source if you want to try fixing it yourself...