The concept of viewports

[CAD4All]

I understand that viewports are feature that is available in QCAD Pro. However, in the Community edition, if one goes to the Drawing Preferences, under "Layout" there is an option "Viewports" and if one selects this options one is presented with a variety of viewport layout options. If viewport functionality is limited to the QCAD Pro, then what is the significance of these options? What do they do?

My interest in viewports arose as a result of my looking for a way of scaling drawings and finding the suggestion that the way to do this is to scale using a viewport. If viewports are not able to be used in CE, how does one achieve scaling in this edition? What I am wanting to do is to produce a floor plan in the model space which is displayed in its entirety on-screen in a paper space.

[CVH]

Hi,

The difference is the duality of the term 'Viewports'.

A) GUI > Layout > Viewports or up to 4 views on your Model_Space arranged in the Graphical User Interface.
B) Page Layouts > Viewports or partial areas of your Model_Space included in a Layout Block.
(Assuming that there is no defined limit on how many.)

- - - - -

What you are attempting is basically an adequate Paper Scale when in Print Preview mode, Page Preview mode.
Please see the Printing tutorial .

Another way is to define it yourself in the Drawing Preferences:
- Paper size and orientation.
- Viewport Scale or Paper scale.
- Viewport Offset = Model coordinate corresponding to the left lower paper corner.

Remark that it is not the Model that is scaled.
Instead it is the paper area that is virtually scaled.
On export it will look as it looks "on paper", the gray background is outside the page.

In QCAD Pro one can use the Layout Block(s) to arrange whatever and however on a page using Viewports.
Typically a Layout Block is viewed in Page Preview mode.

- - - - -

"In its entirety on-screen in a paper space" depends on the zoom state.
Like in Model_Space we can zoom in-out while in Page Preview mode.

With a correct Paper scale and offset your design will fit the paper area "In its entirety".
To see that you need to zoom out (in) to the point that the page fits the screen.

Regards,
CVH

[CAD4All]

Thanks very much. That makes the situation much clearer.

I thought that there must be two meanings of "viewport", but I couldn't find any clarification of that point in the online User Manual, nor in any discussion of viewports in the CE Forum.

Yes. I did realise that scaling didn't apply to the Model itself. I think that the fact that the Model is defined in terms of actual dimensions is a difficult one to grasp initially, at least when it comes to drawing up house plans, because there is no real analog with drawing up house plans with pen and paper. In that case one only deals with scaled representations of buildings. However, once one internalises that concept, it becomes easier to understand the concepts of layouts and viewports.

[CVH]

I think that the fact that the Model is defined in terms of actual dimensions is a difficult one to grasp initially, at least when it comes to drawing up house plans, because there is no real analog with drawing up house plans with pen and paper.

The difference or analog is simple.
In the old days we took a real world measurement and scaled that down to paper size.
For something on paper we scaled the measurement back up to the real world.
Taking a related measurement in real, scaling down for paper ...
... And so on.

The advantage to draw in real world measurements is that we don't need to convert measurements forth and back.
Then metric factors 10-100-1000-1/10-1/100-1/1000 or imperial factors 12-1/12 were easy.
The relation between A4 and A3 is factor sqrt(2).

In a final stage we apply a paper scale and fit the design on a page.
What size of paper depends on the paper scale ... An not or no longer on the Model content or how it was drawn.

It is thus equally possible to draw a house plan in mm if the/your unit of choice is mm.
With a proper paper scale that will fit equally well as in cm-m-inch on any size of paper, for example A4 - A3 or larger.


This methodology is not mandatory.
You can equally draw a rectangle of 210 by 297mm (A4) and scale everything so that it fits the page area.
Called 'Drawing at scale', your paper scale is then 1.0.
But hey, this isn't easier at all.

Regards,
CVH

[CAD4All]

Yes. I understand the value of using real world measurements in the model space. However, I still have a problem in using the paper space.

To get a better understanding of the relationship between what appears in the model space and what one can do in the paper space, I put a very simple figure – a triangle - in the model space. I was able to view this figure in Print Preview. I then wanted to view the figure in the paper space and manipulate it in that space. However, when I entered the paper space by double clicking on the entry in the Block List, the triangle was not visible.From my reading of the User Manual is seemed that when one draws in the model space the figure should appear in the paper space and that it is only when one is using viewports to alter the layout in the paper space (which is not something that one can do in the Community Edition) that one has to take additional steps. However, from what I am seeing it seems that that is not the case. What am I missing?

[CVH]

Hi,

Model_Space is a (special) Block and Paper_Space or Layouts are also Blocks but then more dedicated for a page layout.
You can add content to each Block (Definition) individually like to any (standard) Block (Defintion).

Remark that the Print Preview Mode or Paper Mode is functional for any type of block.
By default turned ON for Layout Blocks, per preference turned OFF for Model_Space.
Typically turned ON for File .. Print commands or PDF export.

Including a representation of a Block in Model_Space is adding a Block Reference (BI).

Adding the Model_Space Block as Block Reference is not functional.
But you can make everything in Model_Space a (standard) Block (BC) and then add a Block Reference in a Layout.

Stiil, your best option is to buy a licence of QCAD Pro and work with Viewports
The cost of a licence should not be that much of a problem.

Regards,
CVH

[CAD4All]

I'm not sure that I understand everything that has been said here, but let me turn to something else that may help me to understand.

I have been looking at the video tutorials which I find very clear as far as they go. I have been looking especially at the video tutorial onboard Blocks. This tutorial uses the design of a park which includes a number of park benches, trees, paths etc as an example. The video begins by showing the design of the whole park (at 0.16 mins). At 0.26 mins the tutor brings up the block list. The block list shows that what is being displayed is the drawing in the model space.

Now, it has been explained that normally what is drawn in the Model_Space is drawn to real world dimensions. However, what is shown in the video is clearly not shown in real world dimensions. The scale at the top shows that the image of the park is about 34 cm across whereas the park itself must be many many metres across. So this is a scaled image of what is held in the Model_Space.

What I have been trying to work out is how to get such a scaled image of the house plan that I am wanting to draw. From what has been explained, my understanding is that I need to display the floor plan in Paper_Space and that in Paper_Space the image can be scaled. Whether or not this is so, the example of the drawing in the video tutorial does not appear to be originating from the Paper_Space. The Model_Space is the block selected for editing.

Obviously, I have some sort of misconception about scaling. However, I still have this misconception after days of reading up on QCAD, watching video tutorials, watching Youtube tutorials posted by other presenters.

[CVH]

So this is a scaled image of what is held in the Model_Space.

Please download the example file park.dxf listed in the video transcript.
The drawing unit of the file is 'meters'.

the park is about 34 cm across

Where does the assumption of cm comes from? CAD is typically in unnamed values.
What a certain size or linear value stands for, depends on the drawing unit.
And yes, then 34cm will fit on a A3 ... 34m not at all without a proper paper scale.

Indeed, the tutorial is all in Model_Space.
Swapping to page preview is not part of the tutorial.

With the park.dxf downloaded and open > Print Preview.
A dialog asks for 'Auto fit drawing to paper?' > Answer yes.

The design is fitted to paper, A4 as landscape with 10mm borders (Original drawing preferences) at a paper scale of 0.00618
This is the best fit, 1:200 or 0.005 would be more appropriate.
5mm on paper would then represent 1m in real world.

Simply enter 0.005 for the scale but then the lower left corner remains 'as is'.
You can center this again on the page with hitting the 'Auto Center' button.

Regards,
CVH

[CAD4All]

From where can the file park.dxf be downloaded? I'm not aware of anywhere where that file is available.

I had made the assumption that the tutorial video was made using a large wide screen and that the units on the scale were cm. So, I realise, now, that that was an incorrect assumption.

I understand the sequence of steps that you have given that would allow the drawing of the park to be displayed as shown.

What confused me was that in your previous post you said "Print Preview Mode or Paper Mode is ..." "per preference turned OFF for Model_Space". From that, I concluded that to use Print Preview one needed to work in Paper_Space, which was the reason for my question about how one gets a drawing that is in Model_Space into a Paper_Space.

One of the limitations of many the Youtube videos intended to teach new users how to use QCAD is that they omit critical steps. The steps may seem trivial to experts but omitting them may make all the difference for new users between Understanding exactly what to do and wasting countless hours trying to get going. Generally, I find the series of Tutorial Videos that QCAD has developed to be excellent, but as you can see, even these have a few gaps.

Thanks for this latest clarification. I think that I should now be able to make progress.

[CVH]

From where can the file park.dxf be downloaded? I'm not aware of anywhere where that file is available.

For example Tutorial: 1.11 Blocks in English > Scroll about a half page down.

I understand your ignorance ... Even navigating the main site is for experts
There's usually more than meets the eye.

Like on the main site we see the ribbon 'Download' to 'Search'.
'Documentation' is a dropdown list but it is also a link.
The content is somewhat different.
For example, List of all Keyboard Shortcuts can be found by the link, they are not listed in the dropdown.


To summarize:
The design is drawn in the Model_Space Block, typically not viewed in paper mode.
You can turn on the paper mode with for example Print Preview.
Related paper settings are stored in Drawing Preferences.

Paper_Space Blocks are special Blocks for additionally and specific arrangements on paper.
For example one for A4 and one for A3 and yet another with some enlarged details.
Paper_Space Blocks are typically viewed in paper mode.
They store their own paper settings.

Standard Blocks (all other) are used for design snippets, to group re-occurring things as one whole.

You don't need to use a Layout Block to present your design on paper.
Still, using a Layout Block with Viewports (Pro) opens more perspectives.

Regards,
CVH