Hello Sankari, I'll be the teaching assistant handling your lesson 4 critique.

Starting with your organic forms it is clear that you're aiming to stick to the characteristics of simple sausages that are introduced here, and some of your forms are spot on. There are a few little inconsistencies, such as sometimes the ends get slightly flattened or stretched out and pointy, or the occasional subtle bulge along the length of a form. Nothing particularly concerning, just things to keep an eye on when practising this exercise in your warmups.

Nice work experimenting with shifting the degree of your contour curves. I'd like you to take a look at this diagram showing the different ways in which our contour lines can change the way in which the sausage is perceived. You're doing great where you want to express a form as having both or neither ends facing the viewer. When only one end of the form faces towards the viewer, we'll usually expect the degree of your contour lines to be shifting wider as we slide along the sausage form, moving farther away from the viewer. This is also influenced by the way in which the sausages themselves turn in space, but farther = wider is a good rule of thumb to follow. If you're unsure as to why that is, review the Lesson 1 ellipses video.

Moving on to your insect constructions there's a great deal here that you're doing really well. You're starting your constructions with simple solid forms, and gradually building them up piece by piece, usually without attempting to add more complexity than can be supported by the existing structures at any given point. You're showing a developing understanding of how all the various pieces of your constructions exist in 3D space and connect together with specific relationships. You're making good use of the methods shown in the demos, and I have just a couple of supplemental pieces of advice for you to keep in mind as you move forward.

I usually spend a portion of lesson 4 critiques introducing students to a concept that we don't talk about much in the lesson material, but will be helpful as you tackle animal constructions in the next lesson.

This advice relates to differentiating between the actions we can take when interacting with a construction, which fall into two groups:

• Actions in 2D space, where we're just putting lines down on a page, without necessarily considering the specific nature of the relationships between the forms they're meant to represent and the forms that already exist in the scene.

• Actions in 3D space, where we're actually thinking about how each form we draw exists in 3D space, and how it relates to the existing 3D structures already present. We draw them in a manner that actually respects the 3D nature of what's already there, and even reinforces it.

Because we're drawing on a flat piece of paper, we have a lot of freedom to make whatever marks we choose, but many of those marks would contradict the illusion you're trying to create and remind the viewer that they're just looking at a series of lines on a flat piece of paper. In order to avoid this and stick only to the marks that reinforce the illusion we're creating, we can force ourselves to adhere to certain rules as we build up our constructions. Rules that respect the solidity of our construction.

For example - once you've put a form down on the page, do not attempt to alter its silhouette. Its silhouette is just a shape on the page which represents the form we're drawing, but its connection to that form is entirely based on its current shape. If you change that shape, you won't alter the form it represents - you'll just break the connection, leaving yourself with a flat shape. You can see an example of this in this diagram showing the various kinds of actions we can take using the context of a sphere.

You're doing a good job of building your constructions additively, I'm not seeing any significant cases of trying to cut back inside the silhouette of forms you have already drawn. There are plenty of places where you're building your constructions up by adding in 3D, which is great. There are a few places where you'd made an addition to a construction "in 2D" by extending an existing form with a partial shape, such as this section I've marked in blue on the head of your ant.

So instead, when we want to build on our construction or alter something we add new 3D forms to the existing structure. Forms with their own complete silhouettes - and by establishing how those forms either connect or relate to what's already present in our 3D scene. We can do this either by defining the intersection between them with contour lines (like in lesson 2's form intersections exercise), or by wrapping the silhouette of the new form around the existing structure as shown here.

This is all part of understanding that everything we draw is 3D, and therefore needs to be treated as such in order for both you and the viewer to believe in that lie.

You can see this in practice in this beetle horn demo, as well as in this ant head demo. You can also see some good examples of this in the lobster and shrimp demos on the informal demos page. As Uncomfortable has been pushing this concept more recently, it hasn't been fully integrated into the lesson material yet (it will be when the overhaul reaches Lesson 4). Until then, those submitting for official critiques basically get a preview of what is to come.

So, here I've marked out a few places where I thought there was scope to make the ant construction more 3D, and this image shows the changes I would make. We talked about the head a bit earlier, and I'd changed the partial shape to a complete form that attaches to the ball of the head in 3D space.

The changes to the back of the thorax and the abdomen are a bit more nuanced, as you had already drawn complete forms here. At the back of the thorax the edge of your additional form followed the silhouette of the existing ball form, defining a 2D relationship between these two structures. By overlapping the additional form with the existing ball form we can show how they connect together in 3D. The addition to the abdomen completely engulfed the ball form you had already drawn, effectively replacing the smaller ball form. In general, try to avoid entirely engulfing an existing structure in the new element you add. This can limit how much actual contact the new mass's silhouette has with the existing structure, and therefore defines a weaker relationship with it. Instead, we can break apart the new mass into separate pieces, as shown here, defining each one's relationship individually, and ultimately yielding a stronger, more solid result.

When it comes to the leg, I'm actually really happy to see that you've stuck with the sausage method of leg construction, and have been pretty conscientious about applying the contour curve at the joints. It is good to see that you've been exploring building onto your basic sausage structures to capture the kinds of lumps, bumps and complexity we see in these creatures. We want to continue to take actions in 3D along these finer elements of construction, by drawing complete forms instead of extending off the sausages with one-off lines as shown in these diagrams.

This approach can be pushed much further, as shown in this ant leg demo and also here in the context of this dog leg demo as this method should be used throughout lesson 5 too.

Okay, I think that should cover it. You're doing a good job and I'll go ahead and mark this lesson as complete.