Monday, 22 August 2011

Game Design and Modelling

Introduction

In this essay I am going to assess the process of building a model and the actual model itself. I will compare this model to another, analysing each models assets determining whether they are good or bad examples. To reinforce the points I make I will bring in other models for comparison where relevant. I will explore the journey of each model from pre- production to final outcome, to illustrate what I am saying I will use photographic evidence to back up the point being expressed.
The models I have chosen to focus my study on I believe give accurate accounts of good and bad practices. I haven’t chosen a specifically ‘bad model’ as I believe it will be more beneficial to look at potential pitfalls in ‘good models’. However I will look at more models where relevant. I will break each model down to explore the full pitfalls that can or cannot be created through good preparation and careful practice.

Pre-Production

Pre-Production is your preparation stage before you begin to model. This will involve either taking photographs of the potential model (this will be if the object already exists) or drawing a model sheet, so the design is sketched in the needed perspectives which are front and side, it is also helpful to have the design in other perspectives such as a ¾ view. I personally prefer to draw model sheets for reference as I can gain a ‘feel’ for what the model is to look like by doing this. The pre-production stage is very important because these drawings become your guide as you model making them something you can constantly refer back to whilst modelling. Your image planes should be set up like this within Maya (see figure 1).
Figure 1 - Set up of image planes
                I have included this image as a good example of how to set up image planes because this is the most effective way to have them set up. This is the best way to set them up as they are in close relation to each other, so you can see both planes allowing you to refer back to both references rather than just relying on one. As if there was too much space between the planes you would only focus on one view point.
‘Without well researched and considered reference, a likeness of a person is extremely hard to capture.’ (Pattenden, 2001-2011) This proves that if you do not have a good reference basis you will struggle to model the desired design, especially when it comes to character models.
Darren Pattenden gathered very good photographs to use as reference for his preparation for modelling ‘Moff Tarkin’. Pattenden made sure that his front and side photographs were the same scale to each other. If they weren’t the same size it would make it difficult to determine the size of the models aspects. Below are the images Darren used as his reference.
Figure 2 - Moff Tarkin - Image Planes
 
Figure 3 - Moff Tarkin - Images scaled to each other
Julian J went against what I have said about referencing, when he modelled a house elf, as he didn’t use any. This could be because he has modelled this before and doesn’t need it. Even if this is the case it is always useful to have references on hand for guidance.
Carsten Lind modelled a cartoon man that I also looked at for this research. He too however did not use any referencing. I consider this bad practice as without a starting point (you’re starting point being your references) then you have nothing to help you through your modelling process which can become frustrating if you’re up against a problem and you don’t know which direction to go next. However I am not saying that a model created without reference is always a bad model  as you may not need it under certain circumstances, for example it may be a really quick and easy model where you completely know what you want to do and what way you want/need to do it.

Modelling

                Your next step after pre-production is your modelling process (production). This is where your design is created.
The head is seen as the place to start with many people. Most people start off with a cube to begin their head modelling, this was the case for Darren Pattenden and Carsten Lind but Julian started with a single plane. Julian used an extruding method, this is where, starting with the eye socket, he took the edges of his plane and extruded them to continue creating the shape of the face. Without reference images set up in Maya this method would prove difficult, personally I would find this a struggle as I wouldn’t know what scale I should make the parts of the face and the specific shape I am supposed to make them. To model in this way you would have to be very confident in your abilities as a modeller. Below are images of Julian’s starting point.
Figure 4 - Single plane
 
Figure 5 - Start of extruding method
As you can see from the two figures above there is no direction as to how the head is going to pan out unlike if you were to start with a cube.
Darren Pattenden used a cube for his starting point but before that he did a little more preparation. To help figure out the facial planes for ‘Moff’ Darren used Photoshop to apply the cutout filter and paint over one of his reference photographs, this helped mark out the bigger planes for the face. Also to further this research he used another photograph and drew on the edge loops to see where they should be going. I had never thought to do this kind of research but believe it would be a very helpful process when modelling the head, as you are giving yourself more guidance. For somebody who hasn’t got much experience and confidence in character modelling these steps could be crucial towards their success. Below are images of these steps.
Figure 6 - Moff Tarkin - Applied Cutout Filter
The above photograph shows the effect of the cutout filter in Photoshop. As you can see it becomes easier to determine the planes on his face.
Figure 7 - Moff Tarkin - Edge Loops
The above photograph shows where the edge loops should be running along his face.
Figure 8 - Moff Tarkin - Head progress
Above shows the stages Darren went through when modelling the characters head. As you can see once the model got to a certain point it become a case of observing the detail of Moff’s face to get the points of his own model where they needed to be.
Referring back to Julian’s model. To shape the head of the house elf Julian used the lattice tool. The lattice tool creates a grid around your model, by using the vertices on the grid you can move and reshape parts of your model. This is a useful tool as you may find it easier to select the vertices on your grid rather than on the actual model. Also this tool can make it easier to reshape what you need rather than without using it. Below is an image of the lattice tool being used on the house elf.
Figure 9 - Use of the Lattice tool
To save time when modelling, a technique that is best used is to mirror your model. So instead of working on the model as a whole, trying to make both sides of the model exactly the same, you can split your cube in half and just focus on modelling half of your design and then when you are happy with what you have modelled you can mirror that half of the model to create the other half. Once you have done that all you have to is stitch up the middle seam that will join both halves together. All three people used this process when modelling proving it is a very useful way of working.
To ensure good edge flow when creating the head Julian made sure that all the edge loops ran into the nostril of the house elf. This can be seen in the image below.
Figure 10 - House elf - edge loops

When modelling the body you could either use the ‘Create Polygon Tool’ or create a series of cylinders that represent each limb. With the ‘Create Polygon Tool’ you draw around half of your front plane image creating a series of points. You then connect the vertices. After that you extrude the faces of the polygon you just created. Once you have extruded the faces it is a case of adjusting the vertices in accordance with the side view plane. Below shows some of the stages of this process.
Figure 11 - Create Polygon Tool 1
 
Figure 12 - Create Polygon Tool 2
 
Figure 13 - Create Polygon Tool 3

The cylinder approach involves creating cylinders to represent the body parts i.e. a cylinder for the torso and a cylinder for the leg etc. Only create half of the body with the intention of using Maya’s mirror function. You need to split the torso cylinder in half to mirror it properly. Scale and adjust the vertices of the cylinders, rearranging them based on the side image plane and then the front. Then you need to join up the cylinders and tweak the vertices to create you basic mesh. Below shows this process being used.
Figure 14 - Cylinder 1
 
Figure 15 - Cylinder 2
                The good thing about using the ‘Create Polygon Tool’ is that you can model the body as a whole including the head. This could save time as you don’t need to stitch up all the separate parts of the body together. However this could also be a downfall as you end up having to focus on the whole body rather than work on parts individually, making the cylinder process just as good. I believe that choosing which process to use is down to personal preference. Julian however didn’t use either process instead choosing to continue with his extruding method.
                Once you get to a certain point with your models it just becomes a case of tweaking vertices to get the shape and look you want.
Figure 16 - House elf
Figure 17 - Moff Tarkin
Figure 18 - Bad example 1 - Torso
                I compared the two main models I looked at (Moff Tarkin and the house elf) to some other pieces of work. It is clear to see that the two I have looked at are of a very high standard of modelling. Figure 17 is an image of a modelled torso, the torso is too rough and edgy, and it looks like the modeller has tried to model the detail of muscle with the outcome not being good, compared to the smooth models of Moff and the elf.

Proportion

Proportion refers to the size and scale of parts of the model and how they look in relevance to each other. In other words, for example when modelling you need to make sure that the head is not too big or too small when on the body otherwise it will look out of place and your model as a whole will not look right. Your model sheets and reference are set up so that you can see what size you need to scale your characters aspects to, without these it would be a matter of guessing and deciding what size you think something should be.
Obviously if you have designed an exaggerated character where some assets of it are particularly bigger or smaller than other parts, your proportions will be different to when you are scaling an average human being.
Julian’s ‘house elf’ has exaggerated proportions as with larger ears and a smaller torso, the scale is different compared to the average human being. Whereas Darren’s ‘Moff’ has the same proportion to a human and has scaled the characteristics exactly to the size they should be, nothing seems out of place being too big or small. Both models have been proportioned very well, no aspects are out of place looking like they shouldn’t be the size they was made. The images below show off the models proportions.
Figure 19 - House elf - Proportion
 
Figure 20 - Moff Tarkin - Proportion
Figure 21 - Bad example – Proportion
                I think that the model shown in figure 21 is out of proportion. I feel that the arms and hands look too small. This makes the model look unrealistic and is not to the standard of Darren’s and Julian’s models. Therefore proving that proportion is very important for the look of a model.

UV Mapping & Texturing

Julian split the house elf into different UV maps. He used an auto UV plug-in that was created by Francois Grassard. A plug-in like this obviously makes it so much easier when having to arrange the UV maps for your model; however I am not sure if this plug-in has been released. The image below shows how he split the model.
Figure 22 - House Elf - Split into UV maps
For the normal bump map for his model Julian used Deeppaint 3D. Using this, Julian painted on lines to represent where he wanted the house elf’s wrinkles to go; this makes it easier to paint the wrinkles when this is opened in Photoshop. In Photoshop Julian put a grey layer on top of the texture that was made previously and turned the opacity down so that he could see the lines from the other layer. Following these lines he painted on the wrinkles using the tools ‘colour dodge’ and ‘colour burn’. For the colour maps Julian used high detail photographs instead of painting his own. Using photographs I believe is more effective than painting your own textures as they look more realistic. Julian used more than one map to create a texture giving it more detail, making the outcome more realistic.
Figure 23 - DeepPaint 3D
Figure 24 - House Elf - Texture 1
Figure 25 - House elf - Texture 2
Above are some of the textures Julian used for his house elf. I believe they are of a good quality showing detail of aged skin and fading tattoos.
I looked at a model by Carsten Lind but have not mentioned much about it. This is because when Carsten Lind modelled his cartoon character the problem I found was that he kept switching from modelling to texturing. He modelled the character’s head and began to texture it but before he finished the texturing he moved onto modelling the body of his character, he kept proceeding to do this throughout the whole production of his model. This way of working may have been what was best suited to Carsten but I think that it makes more sense to complete all of the modelling and then move on to the texturing as you may end up wanting to change part of your model and if this is already textured it could mess with your UV map and mean you possibly have to fix your texture map also. Carsten ended up changing his texture for his characters head numerous times. Both Darren and Julian completed all of their modelling before moving onto their texturing.
In conclusion, from following the development of different models I have come across good practices from different areas of each modeller’s process. Darren’s pre-production and research for his model were very good; he was very prepared for what he needed to do.  This showed in his final model. Although Julian worked in a way that was different from the other modellers and at first glance I saw this as a pitfall, the final model was to a very high standard and is something I would like to be able to achieve within my work.
I didn’t specifically look at one ‘bad model’ as I believed that by looking at potential pitfalls in good models would be more beneficial as it showed what needed to be avoided, if you wanted the model to be of such high standard. 

 



References
http://davegoosem.net/blog/maya/modelling-a-character-in-maya/


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