Organic Modeling & Foliage
From week 9 I started to work on modeling the tree that has fallen into the cabin. I'm sure that my method for creating the tree was long winded, but I find working in ZBrush allows me to create better organic shapes.
I tried not going too into detail with sculpting the tree, I added a few suggestive marks of a birch tree just to better visualize what the end result may look like. Since this mesh takes up the space of more than 4 meters, it is unreasonable to bake down. However I can use a mixture of tilling textures to get a similar look on a lower poly mesh.
This is the initial stage of the re-topping process. Like I said before this might have been quite a long winded process, but since I don't have access to speed-tree I thought this would lead to good results.
Additionally I can break off some of the mesh to create fallen/broken branches.
Here is the full re-topped version of the tree. Something that I want to point out is why I did a stump for the tree. I want to show where the tree originally was, if this can be seen from a window. Or if I expand the range of accessibility to outside, then there should be a stump.
Planning Foliage
When I was planning out how I should approach the foliage I originally thought that I should have everything contained on one texture sheet. However after giving it some thought I realized that it would be better to separate the different species of plant, onto their own separate uv's. This is so that I can better manage texel density and easily edit/change the textures.
Since I had been working on the tree in ZBrush, I thought that I should do the same for the foliage. Being able to sculpt allows me to add details that would be much more difficult in 3dsmax. However the only draw back to ZBrush is that I can get lost in adding details, its sometimes difficult to stop sculpting.
The process for creating my foliage starts with masking the shape/silhouette on a plane. I will often try to get the majority of the proportions correct at this point, as it would save time for later.
From there I cut out the shape and use zmodeler to qmesh the plane and make it into a 3d object instead fo a plane. I also add support loops to the edges to control the smoothing process.
Most of the time is spent in the dynamesh stage, where I will often tweak the silhouettes and add or take away from the mesh. Something that I found difficult with sculpting foliage in general, is that they are not perfectly symmetrical. There is an offset between the two sides, as if the veins are one after another. To speed up the process I would often sculpt symmetrically and then mask one side and move it to offset.
There will be an additional layer of detail, this will often try to break up some of the repetitive shapes and add the smaller details of veins and the cell like structure.
Once I have finalized the details, I then move onto creating variations. Here I use the transpose tool or move brush to offset the model. In this particular case there are some variations on how the dockleaf sort of folds/ripples. It's also important to look at references. I also keep one model completely flat, since I can distort the low poly model if I feel like I want more variations.
Before I move onto the texturing process, I wanted to touch on a quick method of creating hair/flowers. Using the tool fibermesh in zbrush allows you to control hair strands that populate a selected mesh. Using the masking tool controls where the fibers appear as well.
I export the high-poly models into my 3dsmax scene and then arrange the models to how they will fit to the texture sheet. When I arranged the models for the dock leaves I realized I could fit an extra leaf.
Some advice I have to improve the quality of the bake, is to place a high-poly plane below the foliage models. This is to stop any sort of bleeding edges. I found that without this, the area's around the leaves would be inset.
Here is what the leaves look like in Substance Painter. As you can see the texturing process is left quite simple. There isn't much of a need to go too in-depth with the textures. As the more detail you add might make the leaves easy to spot that they repeat in the scene.
Also you might see that the stems of these dock leaves look fairly strange. This is because I used the metal channel to paint a subsurface mask. Since there is no metal on foliage, I re-purposed that channel for other uses. As long as I do the same for all of my foliage, there will be no issues with this.
I then export the textures from Substance Painter and import them into Substance Designer. I use Designer to organize the textures and add more details to the textures. For the base colour I add a opacity mask, and then for the RGBA texture I add a different opacity mask, one that has holes and bite marks that insects would make. This will help break up the repetitiveness of the model.
For other textures such as the stinging nettles I create and add a stem to the texture. I find that adding tiling details such as the stem, is much easier in Designer as I can control the details and know that it will always tile.
After finishing the textures in Substance Designer it is then to the final stage of creating the low poly models. First is cutting out leaves. I find that working in passes, of adding more loops when they are needed works best.
After cutting out the leaves it is then distorting/warping the model to look more like the real life version. I used primarily the Bend and FFD modifiers to get the curves that I want.
The final stage is composing the separate leaves into a bundle. Again looking at references really helps, as it helps composing the models to look correct.
Looking back at the process I know there are somethings that I can do to improve the process. But everything so far has just been a lot of discoveries and self learning. It does take a while to create the textures, but it definitely speeds up towards the end. I also know that I could probably add more polys to the low poly models to get more detail. I can always go back and do so.
Repeat this process three times and this is essentially what I've been spending my time on from weeks 10 to 12.
So far I have created ferns, nettles and dock leaves. I still need to create Ivy and Grass.
Below is my material set up for the foliage. The set-up is fairly simple mainly compromising of controls for subsurface colour, and roughness.
From week 13 I'll be working on texturing the scene as much as I can, whilst also working on the last two remaining foliage. I hope to speed up development, which will be difficult as I'm forced to work from home. Not being able to access the university's computer labs has definitely affected my productivity. But I will try to do my best in these uncertain times.
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