Is 3D coding harder than 2D? Maybe not

In this article share why 3D coding can be easier than 2D coding for young beginners. This result surprised me! I’m not saying that there aren’t any ways in which 3D can be more difficult, but that with the right tool, 3D is just as accessible as 2D if not more so. The short version is that 3D is a more natural way to think about the world. But read on for more detail.

I thought 3D coding would be harder

I have written a lot of educational content for Scratch, p5.js and other creative 2D platforms. Before trying 3D coding myself I had accepted that it would be harder than 2D. This topic has come up in the Scratch community with a forum discussion mentioning that 3D was specifically rejected because “The purpose of Scratch is to teach beginners basic programming concepts, which is best accomplished with a 2D interface. Adding a 3D interface could make Scratch more difficult to learn and teach.” Before I had reason to think deeply about the topic, I had just accepted this point of view. It seems intuitive that 3D would be harder than 2D.

And this discussion on 3D vs 2D makes the case that creating in 3D game engines is harder than 2D, but a lot of the argument is actually around access to 3D assets and advanced graphics and optimisation techniques which are separate from 3D conceptually. When focussing on programming, I would always provide a set of assets anyway, and I wouldn't expect children to be working with 3D graphics shaders. 

There are many examples of children creating 3D in 2D tools, but that's not a beginner activity. Creating your own 3D raycasting engine (which can view a scene from a particular perspective) is a brilliant project for some young people who have significant experience and motivation. My knowledge of this kind of 3D might have influenced my own assumptions. But creating your own 3D engine is a very different task to programming in 3D when you have a 3D engine available.

My experience with 3D coding

When I got the opportunity to create resources for Unity, I used it to explore 3D coding. I was expecting it to be more challenging than creating in 2D. There's an extra dimension to consider, right? So it must be harder.

I should add at this point that my own spatial skills are terrible. I find concepts like rotation hard in 2D. I use techniques like iterating with feedback (computers are fab for that), using maths and logic, and I'm persistent! I thought I might struggle even more with 3D.

Well, I was mostly wrong. Of course, creating in Unity is more complex than creating in Scratch. But the difficulty doesn't come from creating in 3D itself. Part of it comes from working with a tool designed for adults, with a very wide feature set and no built-in assets. There's a learning curve. But 3D didn't turn out to be as big a part of it as I had expected.

I later worked with the Unreal Editor for Fortnite, which provides more structure and a built-in set of assets and devices. Again, it's a tool designed for professionals with a rich feature set to learn. But 3D itself wasn't the barrier.

Why do we assume beginners should start in 2D?

These experiences made me reevaluate my assumptions. I'd always assumed that we start teaching coding with 2D because it's easier. But that thinking didn't seem to match my own experiences.

You do have an extra dimension to consider, but the professional platforms offer visual drag-and-drop editors that help a lot. I did find it hard to work with rotation and perspective in 3D space sometimes, and feedback cycles were a bit slow in the professional tools, but I didn't find coding in 2D with p5.js that easy either when I had to work with spatial concepts.

And of course young people spend a lot of time in 3D virtual worlds, games and social spaces. It was clear that they enjoy these spaces and are experienced in navigating them. This thinking led to me creating the first version of Flock XR with block-based coding in 3D.

Designing 3D coding to be accessible

At the time I was still concerned about 3D coding being harder. I was very aware of my own limited spatial skills and the research on females in general having weaker spatial skills (this may not be true, which I look at in a future article, but I wasn’t aware of the critical perspective on this at the time). One of my key goals with Flock XR was to make creating with technology appeal to girls, creatives and other underestimated groups. The last thing I wanted to do was make it inaccessible to them.

So I built in graphical gizmos to build a scene. The objects in a scene always have corresponding code blocks, which are synchronised. This gives you two different representations that you can work with. I added colour-blind-friendly colour coding for the x, y and z dimensions. And you can use other objects as reference points for rotation and movement.

There are block-based coding tools that surface the concepts of an underlying 3D engine that has been designed for adults. Of course, that is complex and advanced. Flock XR doesn’t do that, it does use a professional 3D web engine, but it heavily wraps it in beginner friendly language and concepts. These concepts are a step towards the professional tools but designed for an earlier point on the learning journey.

When 2D feels harder than 3D

During the same time period as I was creating Flock XR, I was reviewing computing education resources for young children aged 5–7. These resources involved planning routes for floor robots using cards with arrows on. They also involved slides for use on a projector which put 2D programs on a vertical screen.

Oh wow, there was no way I could mentally rotate a picture of the floor robot to follow instructions when the 'floor' was vertical. This was all 2D but seemed incredibly difficult to me. Working in 3D certainly didn't feel harder than this. (Of course, this approach lacks the affordances of immediate feedback or alternative representations too.)

After observing many, many groups of young people creating with Flock XR and just getting on with creating in 3D, I had to reconsider my assumptions. We also had several educators say that Flock XR was easier than popular block-based 2D coding tools.

Hmm, so why doesn't 3D coding seem to be harder than 2D?

What do children think?

I run Computer Science Masterclasses for children for the Royal Institution as a Women in Games ambassador. During one session, I asked a group of 10-year-olds whether they thought 3D coding was harder than 2D.

When they said 'no', I asked them why. I got some excellent answers.

1. “The real world is 3D, so we think in 3D”

Hard to argue with! Our imagination works with representations of the real world which is 3D and spatial. We don’t think in terms of 2D with flat characters that can only be viewed from one perspective.

Many children try to create 3D in 2D. But when the tool doesn’t support this it’s hard work as discussed above. Most children want to create games, animation and simulations, not a 3D game engine!

2. “We play 3D games, so this is familiar”

I've definitely observed this. Children who play 3D games come with a lot of knowledge about how virtual 3D worlds work that they can apply to 3D coding.

We have to be careful about equity here, as some pupils may not have access and we must not assume it. For them, developing this experience that their peers have is important.

3. “In 2D, if you want to make something further away, you have to make it smaller. In 3D, you just make it further away.”

Gah, that was supposed to be the one they didn't get, that I would reveal.

Yeah, a 10-year-old girl realised immediately what it had taken me ages to figure out! 3D offers a more natural representation of the real (physical and digital!) worlds that young people inhabit.

In a 3D world, lots of our knowledge transfers. We can work with different perspectives, objects can be hidden behind other objects, and the concepts of position and distance behave as we would expect. If you want something to appear further away, then you position it further away! We don’t have to think in terms of a 2D projection of a 3D world.

You don't have to use all three dimensions at once

Another point is that very often when working in 3D we're just placing and moving items in two dimensions on the ground. It's natural to start here and then add the up/down dimension later. This means we have the extra benefits of 3D without immediately needing to consider three dimensions when programming.

We’ve found that children spontaneously discover how to use three dimensions in Flock XR either by using the gizmos or because they want to put an object up off the ground and therefore have a need for the concept. It’s much easier to understand a concept if it’s the answer to a question you already have.

Doing 3D vector maths is a bit harder than 2D vector maths, but that’s not something a beginner needs to do. That’s all hidden with friendly blocks that cover beginner concepts.

3D assets included

Flock XR includes a set of low-poly 3D models and animated characters.  These models have been designed to be easy to customise and are based on our co-design work with young people. They models are simplified low-poly both because this looks visually appealing and to make sure they are quick to load. We also provide a full set of animations so characters can walk, dance and wave. This addresses the genuine practical issue for beginners starting in 3D - finding suitable models.

So is 3D coding harder than 2D?

So it seems that 3D isn't automatically harder than 2D. In fact, some concepts are more natural in 3D. And Flock XR is packed with affordances that provide alternative representations and immediate feedback to make creating in 3D accessible.

That isn't to say that creating in 3D (or 2D) space is easy. It requires spatial reasoning skills that some learners will find challenging. But creating in 3D also provides opportunities to develop those skills in a constructionist way - learning by doing in a meaningful context.

One decision we have deliberately made in Flock XR is not to support 2D as well as 3D. Many professional tools such as Unity support both. That’s a valid decision for a professional games platform, but having a tool for children that covers both paradigms would be more complex. Just focussing on 3D allows the user interface in Flock XR to be just simpler than it would be if it also covered 2D.

A note on accessibility and diversity

It’s important to note that not everyone imagines 3D in the same way. Some people have aphantasia which means a lack of mental imagery. Others (like me) struggle to mentally rotate objects. Those who are blind use sound, touch and smell to build spatial representations, and there are conditions that affect depth perception. I’ll cover these topics in more detail in future, but it’s important to be aware that there is diversity in how people perceive 3D space and reason about it.

Can you start with 3D coding?

Do children need to use 2D coding before 3D coding? Originally I thought this would be the case. And certainly lots of the concepts from 2D block-based coding transfer over to Flock XR. If young people have learned how to drag blocks and work with computational concepts such as sequences, loops and conditions, then that knowledge can be applied. Spatial concepts such as move, glide and rotate are also present in 3D form and knowledge of their 2D versions can be relevant.

But now I think it’s quite reasonable to start with 3D coding. Flock XR has been used with children as young as 6. In fact, it was our educator community that alerted us to success with younger ages than we had originally considered.

We now have curriculum resources for age 7 through to age 14+. There’s obviously a progression over time. But younger learners naturally take to working in 3D. And there are some 2D concepts that you just don’t need, like making objects smaller to make them seem far away, or having to create completely different graphics to view an object from different angles.

Release 2 of Flock XR (2027) has improved user experience for younger creators including editing tools for users with less fine motor control, and better support for mobile devices such as iPads that are common with younger ages.

Try 3D coding for ages 7-14+ with Flock XR.