Hi,

I am testing macrogen for 30 days now and am working with patternmaker since a few years. So far so good. I understand the working with points in general.

But could someone explain to me for what practical use the commands arc arc intersect and arc line intersect are used?

I understand how to use but not FOR WHAT reasons?

Hope someone can explain

Hello Monika,

When you draft a pattern using instructions from a patternmaking system they will use a lot adding a point which is the intersection between 2 lines. These lines can be 2 straight lines or a curve and a straight line or 2 curves. It is used a lot when the lines are steep and not vertical or horizontal.
In Tutorial 2 which you can find via Tutorials in the first screen of MG, it is used in adding Point S21.
Where is it used: You can think of as you have a curved line and you want to cut this line at a certain height. Then you would add points to draw that line at the certain height and then the intersection point between the curve and the straight line will be the intersection point, the new added point.
Whenever you use in Patternmaker Snap intersection you will use in MG one of the 3 line-arc possibilities.
Eugenie

Thank you Eugenie,

Point S 21 is a part of the cap of sleeve and is a continue point.

I found examples for all things even line distance for Shoulder width but arc arc intersect or arc line intersect I didnt find.

Monika,

I looked it over again in the manual of MG 4.5 and I find it in chapter 2 Translating drafting instructions / Planning a curve ; on page 30 in my manual(page number could be a little different when page settings are different in USA) the following:

We are going to place corner points in two places: the crotch and the line connecting the hip and waist. First, let’s
figure out the corner point for the hip. We want it to flow smoothly from the leg, so, according to rules A and B
above, the corner point needs to be part of both the leg line and the waist line. We can achieve this by placing the
point at an intersection of the two lines.
Line Line Intersect (21) = intersection between the 2 lines S18-S14 and S7-Start
Pt. Name S21
1 Start S18
1 End S14
2 Start S7
2 End Start

And also S23 is again a intersection point between 2 lines

Eugenie

Ahh ok but this is line line intersect. Therefore I found even more examples but not for "arc arc intersect" and "arc line intersect". Question was if there are practical examples for those kinds of point. Or are they used so rarely?

Monika,

The "arc arc intersect" and the "arc line intersect" are automatically used when editing in PatternMaker and using either snap to intersection or the cut function. The only use of them when drafting a Patter I can think of is if you need a point that is equal distance from two other points. You could create two quarter circle arcs and use "arc arc intersection".

Ok, I understand, I even didnt find practical use so I thought perhaps someone else knows something. But seems they belong to the so called automatically created points - if I understand right.

Hi monika,
the best to understand this function is to use it with the edit Macro (6th button from the left at the top).
When you want to cut a shape and that shape has curves, the new point on the shape (created but cutting with a line) is a arc-line intersect.

That editing function allows you to quit Macrogen temporarily to open PatternMaker and use some editing tools like the cut-a-shape function.

When you close the window and go back to macrogen, the arc-line intersection becomes obvious.

Have a try and follow the picture I have uploaded.

Hi Coco, thank you - this makes sense. I will try examples tomorrow