Region Fill As Brush Question

[Chris Northcross]

I've been trying out some brushes with the Region Fill As Brush and movie brushes and there's some behavior that I don't understand occuring.  I have my brush fill set up set to brush image and I noticed that the individual regions fill don't seem to be opaque but rather are doing some kind of compositing with new regions beneath rather than staying fully opaque.  Why is this?

Here's a snapshot of the images my brush is generating

A quick rundown of some settings for my brush:

Paint Fill Setup: fill from brush, fill to canvas image  Film from mod set to none
Paint Fill Apply: fill algorithm is set to apply, composite is set to replace.  Both depth mast and nib mask are set to none and normal respectively.
Path Brush Load: Is set to 'Image processing' and the source is set to brush.  (Don't think that this should matter..)
Path End: all options are set to none/off

Haven't noticed this before but now (as so often happens with SA4) I'm curious.






Thanks in advance for your help.

region as fill brush.jpeg

[Synthetik]

If you set the preset up like a normal paint preset, the movie brush gets interpolated to fit the region, and then that is used as a brush. So the luminance of the movie frames are blending between the fill from and fill to settings.

What you want to do is fill with the movie brush, but not use the movie brush as the brush that defines the fill from-to blending. You can do this by using the Source Alpha Brush option for the Brush Type in the Brush Type control panel. So then the brush that defines the fill from-to blend will be the alpha channel of the source brush.

Then, if you use the Alpha Only option for the Brush Option in the Region Fill as Brush control panel, the brush source alpha will be generated from the region fill as brush settings, and the original movie source brush will be available for doing the fill.

Here's a quick preset i threw together to show off what i'm talking about.

MovieBrushRegionAsBrushEx1.zip

[Chris Northcross]

That's a big help. Thanks John!

[Synthetik]

Region Fill as Brush pen mode can get a little confusing when you are programing the paint synthesizer, since it normally overrides the Brush Source control panel. The temporary brush is whatever region you manually or automatically generate. However, the Brush Source is still there for use as a fill for things like image or movie source brushes.