topic Re: Hatch pattern: linetype problem in AutoCAD Forum

Hatch pattern: linetype problem

lancionm — Mon, 05 Feb 2024 15:38:08 GMT

Years ago, I would create a USER hatch pattern with a square grid measuring 12"x12" overlaid on a floor plan, and print it. The plan (with grid) would help my client determine if his equipment would fit in a room.

I changed the hatch pattern's linetype to dotted (or dashed) for legibility.

When I do this with AutoCAD 2021, the outline of the hatch pattern (when I select it) shows as dotted (or dashed) but not the actual hatch pattern! It remains continuous!! What am I doing wrong? See attached image.

Even when I put the hatch on a layer with linetype dashed, the hatch still shows as continuous. How can I dash the USER hatch pattern?

Thanks in advance!

Re: Hatch pattern: linetype problem

Kent1Cooper — Mon, 05 Feb 2024 16:36:40 GMT

Set the HPLINETYPE System Variable to 1.

Re: Hatch pattern: linetype problem

lancionm — Mon, 05 Feb 2024 16:40:11 GMT

Wow, thank you. That's so absurd. I'm surprised that this command was introduced, and that the legacy was made obsolete/not the default...

Re: Hatch pattern: linetype problem

Kent1Cooper — Mon, 05 Feb 2024 16:51:16 GMT

@lancionm wrote:

.... I'm surprised that this command was introduced, and that the legacy was made obsolete/not the default...

It's been around since at least as far back as 2015 [as far back as I could find on-line Help using the same kind of web address], and Off/0 [that is, use continuous linetype regardless] was the initial/default value then and ever since.

Re: Hatch pattern: linetype problem

lancionm — Mon, 05 Feb 2024 16:54:36 GMT

Fair enough; whether it was introduced in 2015 or later/earlier, I'm nonetheless surprised that this was introduced at all! Again, thank you for your help!!

Re: Hatch pattern: linetype problem

Kent1Cooper — Mon, 05 Feb 2024 17:47:42 GMT

I found something that indicates it was introduced in 2015. And they had a reason [emphasis mine]:

To maintain performance for hatches with non-continuous hatch lines, choose a predefined hatch pattern rather than loading and setting a non-continuous linetype. Beginning with AutoCAD 2015-based products, the HPLINETYPE system variable suppresses the display of non-continuous linetypes in hatches by default.

Which suggests that if you do a lot of this, and in large areas, it might be worth making a pattern in which the "linetype" [dashes & gaps] is part of the pattern definition [easy enough to do].

defined as:

0, -1,0, 0,12, 2,-2
90, 0,-1, 0,12, 2,-2

That's for 12" square at a Hatch scale of 1 appropriate to your usage. The origin is at an intersection. Play with the details [starting offsets from the origin, relative dash and gap sizes] as you like. Dots instead?

0, 0,0, 0,12, 0,-2
90, 0,0, 0,12, 0,-2

Re: Hatch pattern: linetype problem

Kent1Cooper — Thu, 19 Dec 2024 15:52:13 GMT

@Kent1Cooper wrote:

Set the HPLINETYPE System Variable to 1.

Someone added a Like to this, which brought my attention back to it, and I want to suggest a reason for not doing this kind of thing with continuous-line pattern definitions but non-continuous linetypes assigned to Hatch objects. Consider the difference between these two Hatch objects [the white parts]:

On the left is a Hatch pattern with the dashes and gaps included in the pattern definition [in the same ratio as in the HIDDEN linetype], and without a linetype override assigned.

On the right is a User-defined double-direction pattern [defined as continuous lines], with HIDDEN linetype assigned as a property override on the Hatch object, and with HPLINETYPE set to 1 so that the HIDDEN linetype property shows in the lines in the pattern.

Note that on the left, the intersections in the pattern are well-centered crosses, in accordance with the pattern definition. On the right, however, each line in the pattern gets its linetype override assigned to it on its own, relative to only its own endpoints, and not in relation to other lines in the pattern. So because of the irregularities in the locations of the ends of the lines [caused by the oddball boundary shape], their dash-gap positionings vary, and do not align with the positions in other lines [particularly different in the vertical ones in this case]. The grid intersections are not only not nicely centered crosses, but also not the same as each other.

Another example, with DASH on the left and a User-defined one-direction on the right with an equal-dash-and-gap linetype override:

The stagger from line to line gets thrown off on the right, and some of the ends are longer than the dash length.

So if you care about the nitty-gritty of the look of a pattern in use, it's preferable to achieve the non-continuous aspects within the pattern definition, not in linetype property assignment to continuous-line pattern definitions.