Make the texture engine not affect the brush opacity/flow behaviour

[C2CL]

@Deif_Lou

@Daishishi

On Texture per Dab

1. Blend the brush tip and texture. Resulting in a textured dab.
2. Apply opacity and/or flow to the textured dab.

On Texture per Stroke

1. Apply the flow and/or opacity to the brush tip. Resulting in modified dab.
2. Blend the modified dab and texture.

The “texture per stroke” is almost correct. In the second point, if you blend the dab and the texture you are still applying the texture per dab.
Maybe it’s better to imagine that there in an intermediate stroke image where the dabs are painted. Like another layer on top of the current layer. When one is painting that layer is shown on top of the current layer and when one stops painting (a stroke is finished) it is merged with the current layer. This is a simplification as well, but helps visualizing the process. Then:

• If apply texture per stroke is used (this is my proposal):
  1. create a dab image using the pen tip and modifying it (size, rotation, color options, etc.)
  2. paint the dab in the “stroke image” (possibly with different rules depending on opacity, flow, paint mode, etc.)
  3. create the texture image modifying it with the scale, brightness and so on
  4. mix the stroke image with the texture image using the selected blend mode and strength. A new intermediate “textured stroke image” may be needed, since we’ll have to paint new dabs in the “untextured stroke image”, but we also need a textured version to show while painting.
  5. repeat steps 1 to 4 while a stroke is being painted
  6. when the stroke is finished, blend the “textured stroke image” with the current layer.

I think that’s how it works, but tomorrow I’ll check with Dmitry.

Does it mean that with ‘texture per stroke’, the way it works is that we are just revealing the texture underneath when we are painting? So it is as if the texture is in one layer and we are using a blend mode to reveal it or something. It may not be the exact explanation but that’s the feel when I get when I’m trying it in csp.

[Deif_Lou]

@C2CL

Does it mean that with ‘texture per stroke’, the way it works is that we are just revealing the texture underneath when we are painting? So it is as if the texture is in one layer and we are using a blend mode to reveal it or something. It may not be the exact explanation but that’s the feel when I get when I’m trying it in csp.

You can think of it that way, that is consisten with how it is explained in the page you linked earlier also.

[acc4]

@Deif_Lou

You can try using the halftone filter to emulate the texture per stroke mode and see if it’s similar, although the mode used by it to apply the texture is a variant of overlay. Paint black on white with different opacities and put the halftone with the pattern generator and your texture as a filter mask on the layer. Just as an experiment.

Yes, it exactly comes out the way it’s supposed to look like. Here’s the kra file in case anyone wants to test by themselves : halftone texture test ori.kra - Google Drive

At first it didn’t look like it at all, but it was because the Halftone ‘Hardness’ in Postprocessing tab was set to over 80%. Dropping it to under 10% fixed the problem.

One thing to keep in mind is that it behaves more like ‘Texture per Layer’ in this demo which means the strokes don’t overlap over each others, because (obviously) it uses filter mask/filter layer to get this texture effect.