Dimensions
One thing that still infuriates me when I try to use Blender is the modelling aspect. Dimensions are the most important fundamentals to get right and yet modelling things to the exact size in Blender is really difficult. A lot of 3D-work from people suffers because of this.
This manifests itself with things not modelled to scale as well as camera and lighting problems.
The “Cube” needs to have dimensions for all axes and the size of those dimensions should remain editable. Currently the dimensions of a primitive cannot be changed correctly. It appears that altering dimensions is just another form of scaling and this creates problems later on such as with the Bevel-modifier.
Curves/splines should also have primitive-shapes with editable dimensions as well as interactive entry that respects grid-snapping etc. Shapes are important for quickly ascertaining the size of edited meshes and also useful for vertex placement. eg Car wheel-arches. Shapes are also useful for 3D geometry such as: extrusions and lofts/sweeps.
11 Comments
Hello,
tl;dr: Blender allows for fast, accurate, and precise modeling, and also allows for fully parametric modeling with Geometry Nodes (GN). The difficulty of achieving these is subjective, but is on par with comparable DCC tools.
Funny story. When I finally got into Blender after multiple attempts (~2.4), I was coming from a script-based parametric modeling environment. I found that using the viewport gizmos lacked the accuracy and precision I was used to, particularly when animating. Then I discovered keyboard shortcuts and numerical input. Since then, I've created real-world-scale models of everything from staplers to skyscrapers in Blender.
Blender is as accurate and precise as one chooses. If you wish to use the gizmos, use snapping. It's not as versatile, but neither are gizmos.
Also, if you want parametric modeling, use Geometry Nodes to maintain the editablility of the primitives you use. GN is complicated and "unintuitive" versus editing in the 3D viewport, but you do get precision and accuracy baked in.
As for, "...primitive cannot be changed correctly," this is not true. You can change the parameters immediately upon adding any primitive. This is Blender's way - take an action, edit the results. We lose the ability to change primitives once we take any other action, and this has long been a complaint in the community. This is in part why we have GN.
As you discovered, manually changing the dimensions in object mode merely scales the object. Many tutorials warn against doing this (or suggest to apply the scale) because it messes with things like bevels. Better to do these things in edit mode.
Wow. You found my post too long and didn't read it ("tl;dr: Blender...") but chose to down-vote it anyway and then wrote about 100 words more and in those words you illustrated that you have no idea about what you are writing.
No need to be snippy. "tl;dr" doesn't mean they didn't read your post, it means "summary of my post if you don't wanna read it all because it's kinda long".
Try not to take downvotes personally. People might downvote you even when they agree with the gist of your request, if they find your solution to that request to be wrong or unhelpful. As an architect, for ex, I'm always on the side of more precision tools in Blender, but I don't see any tangible suggestions in your post as to how to make that possible. Not to mention you're wrong about how you can't change the dimensions of primitives correctly—you can, you either have to apply your scales in Object mode, or use Edit mode. You can enable "Edge Length" (and other) overlays in Edit Mode for precise information about topology as well.
Primitives will probably be fully parametric Geometry Nodes setups in the future, so that part's already "in development" in some sense. For (many) more curve primitives you can enable the "Add Curve: Extra Objects" addon that comes with Blender. They have many settings you can edit upon creation. You can always use grid snapping (or other kinds of snapping) with all kinds of geometry.
So that leaves... what?
I wouldn't mind the downvote if he actually knew about what he was writing.
Historically architects have not been great at 3D work which is why Architectural-Visualisations have been done by 3rd parties that typically use 3Ds max. 3Ds max is an example where you can change the properties of primitives for perpetuity, but that feature is not unique to 3Ds max.
"Not to mention you're wrong about how you can't change the dimensions of primitives correctly"
Really, make me a box with the dimensions of 4000mm 2000mm 1500mm and fillet/bevel the corners without going into edit-mode and taking 3X longer than necessary. In Blender the Cube has only one dimensional parameter... Scaling in object-mode causes problems (not unique to Blender).
Geometry-Nodes is a completely separate method of "Modelling".
So you don't know about what you write either...
Blender is deficient in an area, I raise that deficiency and then I have to fight through people like you that really don't know about what they write and I get called "Snippy" It is just really irritating and not the first systemic problem with Blender-development either. For example the stubbornness over the really awful user interface that wasted years of people investing into the project. (Hence the name of this forum)...
Make a cube.
Go into edit mode, move the top single face along the z axis so that it's no longer a perfect cube.
Without leaving edit mode, how high is the cube now?
Select all the points. There's a transform palette right there on the panel.... it doesn't show me the XYZ dimensions.... why, exactly?
Yes Sir!
Make a cube. DONE
Go into edit mode, move the top single face along the z axis so that it's no longer a perfect cube. DONE
Without leaving edit mode, how high is the cube now? 3.19371 m (the local z for the top plane plus the default 1 m to the bottom plane).
Select all the points. DONE
There's a transform palette right there on the panel.... The N-Panel, yes.
it doesn't show me the XYZ dimensions.... 2 x 2 x 3.19371 m (for reference)
why, exactly? It is not a display of Object dimensions, but the median of the combined values of the selected vertices, either in Global or Local (default) space.
simon2: "...without going into edit-mode and taking 3X longer than necessary."
thorn: "Go into edit mode..." philip: "Go into edit mode..."
If you go into the object properties of the object, its size cannot be edited, but location, rotation and scale can. However, scale is a bit pointless on account of the problems it causes.
Add cube interactively is often pointless and doesn't snap to grid.
If you want to model a 3D object using a collection of photographs on another screen, it is useful to be able to QUICKLY create boxes with dimensions that correspond to the maximum dimensions of the object in question. Items in a kitchen for example such as kitchen-units, fridges, cookers, ovens etc.
If you want to model a new car but don't have detailed blueprints, you want a bounding box based on the dimensions from their website so you can model the car from the review-video/photos of it.
Hello,
I ignored the ad hominem assertion that I do not know what I'm talking about because another had already pointed out the misunderstanding of "tl;dr".
My response to thorn gave me another opportunity to reply to your reiterated slander in third person ("if he actually knew about what he was writing"), which I considered momentarily, but figured I was correct to let it go before, and nothing had changed.
But since I have been dragged back in, I stand by my statement that the functionality you seek already exists in Blender. And correct me if I am wrong, but I think thorn's request for information was implicit support for the proposal (considering they voted for it).
I admit I did not read much of your earlier post, having started to skim after that first line. So let's do that now.
Something about architects and 3DS, then a quote, then a scenario much more complicated than the one referred to in the quote. I could make the box and add a bevel modifier, but this may still not meet your needs. And you added the stipulation it should not take 3x longer than necessary. Define that time please, for reference.
Next you make a bold claim: in Blender, cubes are one-dimensional. So, yes, I don't know what you are talking about. I am not saying you are incorrect, I just do not understand your perspective. Cubes are 3D, as I demonstrate in the video below.
Geometry nodes: I completely agree; it is a different way of modeling, and not suited to a lot of things.
We'll skip that next line.
Full disclosure, I cringed when I read the word "snippy," but their point is valid. I still do not know what the point of this proposal is. As for fighting, I mean, that's a big old red flag there. Asking for clarification is not fighting, it's discussion.
So, "the really awful user interface." The RCS paradigm frustrated my efforts all the way back to the 2.3 series when I first tried to use Blender. I did not try again for years. Then I found that I could change the behavior to left-click select, and things got better.
I was for changing the default to LCS in spite of the fact that RCS is ergonomically better. That is, RCS is the opposite of a really awful user interface. I cannot explain the ideas, but if you ever get a chance to ask Ton, just listen politely and he will lay it all out. It's also in some Conference videos I'm sure.
Now, the video.
You laid out another scenario. The video shows me accomplishing it in what I feel is a very reasonable time (~1.5 minutes). I made 5 boxes at various sizes and in mixed unit systems (I had a different thread in my head). I placed default cubes at their starting locations, and worked from there.
Note that I did enter edit mode to make the origin flush with the ground plane for 3 cubes as I was envisioning these as buildings (or perhaps kitchen appliances?) In the end, I selected all, and applied the scale.
Dimensions used: 40' x 40' x 100' 3m x 15m x 35m 12' x 10' x 12.5m 17.6 cm x 1' 5" x 2.7m 73" x 50 cm x 1.65 m
Because the proposal is titled "Dimensions," that is what I focused on. Specifically from line two: modelling things to the exact size in Blender is really difficult.
I believe we can agree that you can model to exact dimensions in Blender. In multiple ways, in fact. Difficulty is subjective, but a minute and a half for five oddly shaped boxes ain't bad. If this demonstration does not make my case because you have thought of another thing, I'm not playing that.
youtu.be/ajtlz9GYwdU
And finally, I would ask anyone who voted for this to please, in 1-2 sentences - describe the change(s) being asked for.
I think this proposal is about improved object modelling tools. Like Boxcutter?
I agree. Blender modeling tools are designed to be quick for organic models, such as sculpts, but when it comes to precision modeling, they feel uncomfortable, lacking. For example, the "Cube" active tool is absolutely useless, because there is no way to input the dimentions of the primitive while drawing it. I believe that precision modeling should take priority. There needs to be very obvious well designed methods of inputing precise values when using modeling tools, moving objects, aligning them, more better snapping options, polar direction snapping and so on.
it would be convenient for the size of the selected model, length, width, height, volume, and size to appear here in Edit Mode. I don't want to install addons showing the size on the model, it's not often necessary, and it would be convenient to see the size of the model, the length of the edge or the sides of the faces in the menu. I found a measurement. It's inconvenient when a lot of footnotes are shown on the object itself, everything is mixed up there, the output of footnotes under the arrow would be more beautiful, but it's still inconvenient to constantly see a lot of numbers when highlighting a large number of objects edges or faces. in the transformation tab, it's high time to add items of the size of the selected part. length area, height, width. blender.community/c/rightclickselect/mYEr/
When you go into edit mode you can press on the two overlapping circles on the top right you can enable Edge Length, Edge Angle, Face Area and Face Angle