difference between PLACE FREEHAND SKETCH and PLACE POINT STREAM CURVE ?

As per subject.

  • Morning Thomas

    I know I can ’digitize’ the original drawing with Smart Lines – but then you end trying to have lines parallel, run into problems when the original isn’t ortoganal, skew etc, And many many clicks. Then it is better to really reconstruct the drawing  and have a drawing also usable for cad. In my case I only need this as illustration.

    Ultimately, it's for you to decide what approach will get you the end result you desire, nobody else can make that decision for you, but of course you can take into consideration advice if others have done similar before. I've drawn up many old buildings in my career and even if there is some slight variance in wall angles, more often than not it was perfectly acceptable to draw them orthogonally, if they were only slightly off the straight. However, there are also times when a true representation of textured wall surface is required.

    e.g. Here's a screenshot of a viaduct cross-section which I created from a point cloud about 5 years ago. I could have created the outer wall profile using a narrow Clip Volume and Place SmartLine, but I ended up saving myself a fair bit of time using Descartes to horizontally drape a line onto the Point Cloud, which I then refined afterwards.

    Example source point cloud:

    I'd be surprised if your old building requires such an extreme variance as this rough stone façade. I'd be interested to see a partial screenshot of what you are working from, and also the illustration output that you want to end up with.

  • I know I can ’digitize’ the original drawing with Smart Lines – but then you end trying to have lines parallel, run into problems when the original isn’t ortoganal, skew etc, And many many clicks. Then it is better to really reconstruct the drawing  and have a drawing also usable for cad. In my case I only need this as illustration.

    So I wanted to explore the possibilities with the pen tablet. Mostly to see if it is as fast as I hope. Background here is I have used Onenote on a Samsung pen tablet taking notes and sketches on drawings.

    I agree, beziere and Place Point or Stream Curve are no good.

     Place Freehand Sketch seems to be a preset/fixed version of Place Stream Line String.

    Give many vertices, but I don’t see any editing down the road in this project.

    It is not so fast as on a tablet so you can write. But doable for tracing.

    (a bit difficult to  evaluate currently because the Sketch command is a press-drag-release. And the release didn't work properly - a hardware sensor problem according to Wacom support. So the tablet is on its way to service...)

     

    regards /Thomas Voghera

  • What is the differenece between a linestring and a curve element more precisely?

    But I have a project with a building from 1920 and only scanns of old drawings. Tiffs and pdfs.

    Parts of the building are rebuillt so there is no good over all drawings.

    I can trace by hand on paper and pick from the best scanns. But I have a Wacom Cintiq 16 pen display and thought of tracing the drawing there.

    Stream Curve have more settings - but setting them to small numbers it seems to do the same job

    Seriously, don't even entertain the idea of using those commands for tracing over old drawings. Stick to Linestrings & Arcs or you will be in a world of pain if you have to make serious modifications due to the excessive amount of vertices that those other commands produce.

  • Yes I have tried, and they seems very similar.

    No, I haven't used them earlier.

    But I have a project with a building from 1920 and only scanns of old drawings. Tiffs and pdfs.

    Parts of the building are rebuillt so there is no good over all drawings.

    I can trace by hand on paper and pick from the best scanns. But I have a Wacom Cintiq 16 pen display and thought of tracing the drawing there.

    Stream Curve have more settings - but setting them to small numbers it seems to do the same job.

    What is the differenece between a linestring and a curve element more precisely?

    regards /Thomas Voghera

  • Have you tried the commands?

    Place Freehand Sketch creates a linestring element after holding down your left-mouse button and moving your input device across the screen, however, there is not options to configure the detail level of the created linestring. Place Stream Linestring is a superior command IMO.

    Place Point Stream Curve creates a curve element using either points or a Stream. In Points mode, the resulting curve is somewhat similar to a B-spline curve, but at the same time, vastly different as it can contain much more linear segments than a B-spline tends to during its creation. Personally, the command has never had any place in my workflows and having compared its output with similar commands, I can't think where it would ever be useful.