Thinking of writing a perspective tool for krita

[Brendan Scott]

On 24/04/15 15:59, Wolthera wrote:
> No, sorry. Python support is something we really want to get in, but
> there's been no funding to pay for the necessary time we need to dedicate
> to it.
>
> As for the perspective tool, I understand the perspectice grid is a bit
> difficult to use, but we also have several tools in the assistants:
> https://www.youtube.com/watch?v=OhEv2pw3EuI
>
> Or were you thinking of something else entirely?

I think the assistants are awesome. In fact I built my own copy of 2.9(.2) just
to try them and can see lots of places where they would be useful.

What I was thinking about is:

* In 2 point perspective it's pretty standard to have a horizon line. There's
no easy way to set up two points on a horizon line - for example it's hard
to be sure that the assistant is even horizontal (shift will work for normal
lines, but not apparently for the assistants). This is probably my main issue
atm.

* In the drawing of the church the artist was "eyeballing" the distances. There
is no (easy) way to check the correspondence between distances in each of the
axes established by the perspective view. That is, the assistants allow you to create a
rectangular prism in perspective space but there's no simple way of ensuring that
sides on different axes are of equal length (eg: can't draw a perspective cube).
This is achieved through the use of measuring points and a distance point.

See the process explained here:
http://architecturerevived.blogspot.com.au/2014/01/how-to-draw-perfect-cube-in-perspective.html  

To create these you need to be able to measure pixel distances (to set the
measure points) and right angles (to get a point called a distance point from which
the measure points can be calculated). Short of putting a set square up against my
monitor I couldn't see how I could get this point through Krita (I could "eyeball"
it I guess but it seems it should be easier).

Thanks


Brendan