Bug 297971

Thanks.

Here is some tests about Flow:
http://i.imgur.com/kkUcFbz.png
http://i.imgur.com/u5a8aVF.png

And here is the explanation what need to do if someone cannot find Flow :)
http://i.imgur.com/jsF8e7M.png

>> Flow and Opacity need to have independent sensors entries

Today, I've hit a wall in my research for finding a softer preset with Pixel Brush. I wanted my preset to get a better response to the pressure, and a softer look.  I figured I needed pressure on the Flow value to reach the effect I wanted on my brush stroke, along pressure on the Opacity value. In Krita, a pressure curve on Flow along a pressure curve on Opacity still can't be set. Flow value is still linear in Wash mode and the slider is obsolete when switching to Build mode. In fact, when switching to 'Build mode' the opacity sensor transform into a 'Flow' opacity. 
Thank you for your consideration on this Flow/Opacity bug.

Hi, I did research this evening on the code of 'flow' and 'opacity'. 
on /krita/plugins/paintops/libpaintop/kis_pressure_flow_option.cpp

I tweaked the line .91 :
>> painter->setFlow(quint8(getFlow() * 255.0));
into :
>> painter->setFlow(quint8(getFlow() * getDynamicOpacity(info) * 255.0));q

My goal was to use the datas of the 'opacity curve sensor' ( getDynamicOpacity(info)  ) merged into the Flow ( getFlow() ) linear value, and turn it into a dynamic setting.
Results are good : ( http://i.imgur.com/8uYMeEq.png )  I can get opacity pressure AND flow pressure with this ; using same dynamics ( witch is fine ). The problem of this tweak is it force all preset to do this usage. It's bad, and does bad things on other brush engine than pixel brushes. 

A checkbox to activate or not such a basic 'Flow' dynamics ( one who copy the 'Opacity' dynamics curves ) could be a cool enhancement of the pixel brush engine. But this , I have no idea how to do it. It certainly beyond my nooby skill.  :-)

Well, we can do that, no problem :-).

oh super, thx !

Here is a mockup idea, for Pixel Brush, Opacity panel :
__________________________________

Opacity:  ███████1.00███████
     Flow:   ███████1.00███████
☑ Flow Dynamics
__________________________________

Video reference :
==============
FengZhu video – EP 34 - Photoshop & Wacom Basics Part 01 ( the video should start when he setup his basic brushes , at 11m34s )
link : http://youtu.be/eaH_WlD_rP4?t=11m34s
[ Note : Feng Zhu says a mistake about 'Flow jitter/dynamics' parameter in Ps , he says this settting is for "thick or thin" the start of his lines.  It's not, it's for the dynamics of the flow ( painting dabs individual opacities ). The size of his brush is managed by the top checkbox 'size dynamic'. ]

Description :
==========
His default brush-setup ( simple pressure curve on Flow and keep Opacity linear and control it manually with keyboard ) makes subtle flow variation on the start and ending of his strokes while keeping the core of the stroke 100% full opacity. FengZhu uses this for all his brushes according to this video and recommend it to his students, and channel suscribers.   

Problem :
========
It's currently impossible to replicate this setup in Krita because Flow and Opacity not being independants.  On Krita, you can :
- Or use pixel-brush Build-up , and get only Flow dynamics ( overwritting opacity sliders ) with 100% opacity locked. 
- Or use pixel-brush Wash, and get only Opacity dynamics ( and flow become linear ) with Flow possible to tweak, from 0% to 100%, but linear, no dynamics. 
I admit it's frustrating to cannot try this, and my workaround on previous comments ( #4 and #6 ) can't fix this.

Yeah. FengZhu is one of the best CG artists.

+1. We need to separete Flow and Opacity curves.

fixed in commit 1104470ee0258c2ca884ed6d390e89e700d1e747