Friday, 24 December 2010

Texture Tests

Karl gave me some of the objects that he had modelled so I could practice texturing on them. For this I was mainly trying out different methods of texturing and seeing which styles work the best for the objects I was working on. I first started by working a teddy bear which will be a background prop in our scene.

This image shows nothing more than a flat colour applied to the bear, if we decide to go with a more stylised look for our animation then a flat colour like this may work the best. This was easily done by changing the colour of the lambert material assigned to the object.

This is a fur texture applied to the lambert layer, rather than fully UV map the whole bear I quickly applied it just to see the general look it has. I think for a background prop the amount of detail on the bear is acceptable and doesn't need to be anymore complicated than that, however some parts of the texture are too dark so if we were to use this then I would have to edit the texture in photoshop properly and make sure the bear is UV mapped so it will wrap around the model correctly.

The image above shows how I used the fur texture as a bump map on the bear. This didn't provide the outcome I was hoping for instead making it look like the bear is made of a rough material or something like concrete. 

I thought that the sack texture which I used on the sphere in my last bump map test might work well but even that doesn't look quite right as you can see above. 

I decided to try using the fur attributes already in Maya to see how they work with the object. I instantly came across a problem which was that for the body the fur doesn't seem to attach to the geometry but almost looks like its coming from within the body. At first I thought it was a problem to do with the type of fur that I had selected to use but I had the same result with other fur types as well.

I tried shortening the fur which worked really well for the arms, legs and head but still the body would not have the fur applied to it for some reason. I figured the best way to apply the fur would be to have the arms, legs, head and body as separate pieces of geometry and then apply the fur individually like that.

Thursday, 16 December 2010

Bump Mapping

This is another series of tests which are a little off topic to what I've been doing previous, but also they're completely relevant at the same time. I was experimenting with Bump Mapping in Maya, Bump Mapping is a surface shader which doesn't alter the geometry but gives the impression that the object has bumps and depth to it by taking the white and black values of the image you're using as the shader and then altering the height and depth of the protusions by the light being used in the scene. So you could have a flat plane with a bump map applied to it and it will look like it has bumps and texture in the geometry, but the geometry itself will remain unaltered and flat like it was when you first made it. Through my research however I did find that there is a process similar to this one called Displacement Mapping which does alter the geometry.

I started practicing with Bump Maps on a File from my second year, it's a broken old fountain which I made for my groups Digital Environments project. The image above shows the scene file before I started practicing on it, as you can see the textures themselves look rather flat and unrealistic.

This image shows the same fountain after I applied a Fractal Bump Map to the texture on the fountain base. You can see that there is slightly more depth to the shadows, however the Fractal Map I used isn't really the best one for the type of texture the fountain is supposed to be, but adjusting the maps attributes properly should allow for some effective results, but generally using the pre loaded Bump Maps in Maya will produce mediocre results so it would be best to use my own textures for it instead.

The image above shows my first attempt at using images as bump maps rather than the pre-loaded ones already in Maya. I set up the scene using nothing more than a sphere and a plane, I then applied a sack texture as the bump map for the sphere and a wooden plank texture as the bump map for the plane. Now the sphere and the plane look like they are actually made from real materials rather than just having flat textures applied to them.

The above image shows the scene file in Maya, I have hardware texturing and High Quality Rendering turned on so I can see how the scene will look without having to keep rendering it, tis is useful as I found that adding bump maps increases the render time quite a bit and this is only for 2 basic polygon objects. I added a couple more planes to build a little set so I could do some more experimenting.

This is a render of how the scene looks when rendered.

What I wanted to try now was to see how placing a light in the scene would work with the Bump Maps. I used a directional light and loosely placed it just so I could get a shadow from the sphere against the ground plane and the wall behind it. I'm not at all proficient when it comes to using lights and everything I do has no method behind it, all i know is the type of effect i want to create and I reach that by nothing more than repeated trial and error. In the image above the shadow is too dark and bold, I wanted something a bit softer and more subtle rather than bold and in your face. 

The 3 images above are renders which show further experimenting with the shadows, light and colour. What i've found from doing this is that Bump Maps are definitely useful for objects which are not being seen close up to the camera, so objects in and around the environment in the background would benefit the most from this process because up close it can look very messy. Also after doing this I've found that it may not be necessary to use this method at all just because of the style we're going for which is a more simple and stylised look rather than a realistic detailed look.

One problem I found whilst using my own textures as bump maps was that once I had applied it to the object and closed the attribute editor for the shader it was impossible for me to find the editor at a later time to adjust the attributes of my textures, I searched in the outliner for it as well as through all my material tabs but couldn't find it anywhere, it has to be in there somewhere but I just can't find it at the moment. the problem this is now causing for me is that I have to make sure i have the attributes set exactly how I want them before I close it which is annoying because I will constantly be adjusting the settings to get the best outcome.

Wednesday, 15 December 2010

Fur Tests

This is a little off track to what I have been doing previously but it's something I wanted to try out and experiment with. One of the characters in our group animation is a teddy bear, when the character was being designed by Karen we had to decide as a group how the bear would look in Maya, whether it would have fur or just a flat texture. We all knew that having fur in our scene would greatly increase the render time and ultimately cause problems, but I was curious to see how fur actually works and looks once rendered.

I started to experiment by adding different fur materials to a sphere, what surprised me was how many different styles of fur there are and that the majority of them were nowhere near suitable for what we wanted for the teddy bear. Below are some of the render tests I did with different types of fur.

This fur is a bit too smooth and tidy.

Too long and scruffy.

The colour patches are not needed for Karens design.

A possible winner, but the fur looks a bit rough and hard instead of the soft feel that we want.

Too spikey, could be used for grass or wheat.

Too curly, almost looks like it could be itchy and uncomfortable.

Looks too sharp and rough.

The clumps look a little strange and don't suit our design choices.

The settings for each fur type can be manipulated so they can be changed to look more like you want them too, but getting the right style is incredibly difficult and requires a lot of time and effort which I can't afford right now as it's being spent on more relevant areas of work at the moment.

The render time was generally pretty long for just fur applied to a static sphere with no lights or anything else in the scene, plus the fur hasn't been animated so that would definitely bump up the render time. These shots are also rendered in low quality, the final renders of our animation will be in HD which will significantly increase the render time, depending on the amount of time we have for rendering this will not be practical to use. I will also play around with animating fur soon, just to see if it is practical or not to use on our project.

2nd Test

I originally planned to UV Map the whole of the 'Max for Maya' rig, however I encountered some problems to do with the assigned materials to the character in the hypershade, it seemed like the rig was locked and I couldn't assign any new shaders or materials to the geometry even though I could remove them, this was a problem because I needed separate Lambert materials for for the body and the head and since it wasn't allowing me to alter or change anything I had to call quit working on it and find a different rig. The rig I needed to successfully practice on would need to have no UV Mapping in the Texture Editor and for ease of use not have too many materials assigned to the geometry in the Hypershade.

I ended up going through a lot of commercial rigs before I could find one that suited my needs. I started working on a rig called 'Moom'. Before fully unwrapping a character in Maya, I wanted to try a technique where you select parts of the geometry and save it as a 'Set', after this you can quickly select whatever Set that you want to quick select different parts of the body geometry instantly, doing this also unwraps the geometry in the Texture Editor. The best thing about doing this is that it applies a checkered texture to the sets which shows how the textures will wrap around the geometry, this is useful to see if the UV mapping I've done is efficient and doesn't stretch any imported textures or apply them in any odd ways to the Sets, it's almost like a preview to make sure everything is layed out properly before you start working in photoshop on textures and then finding out problems once you start trying to apply them.

Using the Paint Tool in Maya I quickly selected all of the faces which make up the characters Torso. Using the Paint Tool is a lot quicker than selecting each face individually and you don't have to worry about selecting faces behind the ones in front because it will only detect the ones that are visible through the current view that is being used e.g. perspective, top, side. It's also much quicker than selecting each face individually with the Select Tool.

Once I had selected all of the faces that I needed,  I went to Create > Sets > Quick Select Sets and made a new set called 'Torso', after that, whenever I want to select the torso just on it's own I would only have to go to Edit > Quick Select Sets and then pick the Set named Torso, this will select all of the faces in the set and allow me to work on them rather than having to reselect them all individually every time that I need them.

Once I have the Set selected I have to make sure I have 'Hardware Texturing' turned on in 'Shading', after that I can make a Planar Projection which will then show a checkered texture on the geometry. As you can see in the image above, the black and white checkered pattern is layed out equally on the geometry and has no signs of tearing over the object which means that it is a good UV Map and any textures I make in photoshop will apply to the character perfectly.

In the above image you can see that the checker pattern has more black and white squares to this, this is because you can adjust the size of it as well as rotate it to make sure that it is laid out correctly on the geometry.

To make sure that i'm competent with this process I tried it out on another rig of a Troll. I made a UV Set of the trolls chest and stomach and then made a planar projection on it. The checked texture laid out fine so I decided to do the next step of taking the UV map into photoshop, painting a quick texture and then applying it to the Set.

For some reason when I applied the texture it would not work properly, it was tearing and smearing over the geometry and I couldn't find out why so I went back and re-did everything in case I had made a mistake along the way.

After re-doing it all it seemed to work alright, I still don't know what went wrong whether it was something that I had done or if it was just Maya having a little glitch. I still noticed one major problem though which I found to be very frustrating, In the image you will see that on the top and bottom part of the texture there are grey parts which look like they have been left blank; at first I thought that it was something to do with the materials in the hypershade but when I checked there was only 1 Lambert material assigned to the geometry. I'm still not entirely sure what the problem is but I've found this whole process to be more hassle than it's worth. As long as I unwrap the models I'm working on in a logical and simple way then there should be no reason to go through this process of checking the UV layouts with a checkered texture. I personally still prefer the process of painting the texture in photoshop, applying it to the model and then making adjustments back in photoshop if it's not working correctly, I feel I have more control doing it that way whereas this method still seems a little flaky and unreliable, however I will not completely dismiss it because I'm positive that it will be useful for more organic shaped objects as well as a lot of hard edged ones.

Above is the texture I made for the testing of this process, it's very basic and has only he minimum amount of colour and tones to show enough of the detail required to know if it was projecting properly on the geometry and was applied in the correct place.