Tuesday, 14 May 2013

Reflective Journal - BA3



Making a rudimentary level in Maya.

I decided to base the work in this project on the actual architecture of NUA itself. Many of the buildings are old and date back several hundred years, with modern renovations creating an interesting juxtaposition – metal and plate glass against non-uniform brick, ect. Also many of the shapes are relatively simple from a 3d point of view, and I’m not yet experienced in modelling.

I collected a bunch of reference photography of some of NUA’s buildings.

I decided to create an original environment comprising various parts of the NUA buildings cobbled together, with the tunnel under the bar as the central focus. I made a rudimentary Maya model, using a figure exported from Mudbox (.obj) as reference for an average human’s height.

I quickly decided this would be too complex an environment for my first proper go on Maya, and so chose to focus on a smaller element to practise on. The main entrance to one of the buildings caught my eye, as it’s sandstone blocks would be easy to replicate as a repeating texture. The blockiness of the entranceway felt like the perfect structure to practise my 3d modelling on.

Again I constructed a simple maya model to get to grips with the shape, and how I could construct it digitally.

I placed a reference photograph on a flat plane in Maya to use a template in getting the right proportions. The orthographic view from the front has no perspective, so it’s important to use that angle. For lack of a human body model (I don’t have Mudbox on my laptop) I used this orange cuboid and scaled it to the average height of the figures in the photo. The figure guide and reference photograph are put onto separate layers to the actual entrance work, so I can get rid of or hide them later on.

I did try to keep the structure relatively simple and blocky, so as to keep unwrapping the UVs simple.

Planar mapping is particularly useful while unwrapping, as it can be used to join several adjacent faces together early on in the texture editor.

The checkerboard texture is used to make sure the scale and orientation of the UVs is correct across the model. Once the model is properly textured, it should look something like this:

However, applying a placeholder texture to the entrance shows that some UVs do not reflect a consistent size across the whole model. This could be fixed at a later stage via subdividing large faces.

The metal railings can be made using a single face which is semi-transparent. I used a photograph of the bars and erased the background to get the required ‘diffuse’ (colour) map.

I saved the bar diffuse map as a PNG, which when imported in Maya grants the required selectively transparent effect. I could do something similar using and independent alpha channel map.

The stairs only really need a grey stoney texture, sourced easily enough off the web.

I used the program Crazy Bump to make a rudimentary bump map to give the stone a bit of depth to it.

As it turns out, UDK doesn’t like already compressed image files(something to do with recompressing them in the import process) so I’ve had to resave the texture files as TGA or BMPs. This had the added complication of meaning that I had to add an alpha channel to the metal bars, as opposed to simply using a PNG. Applying an alpha channel is actually rather simple, and can be done quickly in photoshop.
Changing the texture filetypes succeeded in allowing me to export the model of the entrance with the textures attached. This speeds up the import process in UDK, as I would otherwise have to import and place the textures separately in UDK. A successful UDK import does this automatically for me, however.

Here is a test of the entrance as it appears in UDK:

A minor issue I have encountered is that the glass door texture appears on the wrong side of its face. This is only observable in UDK, as Maya shows textures from behind the side of the face they are mapped to. The easiest way to fix this in Maya is to spin the face 180 degrees.

Added wall behind entrance and ground to the environment.

The model looks pretty good in UDK, but again some of the textures are projected on the wrong side of their faces. This will need correcting in UDK.

Changing the side on which the textures are projected is done by inverting the normals of the faces.
The ground texture is made from my own photograph of the paving at NUA tiled together, with a grungey texture sourced online to add asymmetry.
I applied an ambient occlusion map to the brick wall, importing it into the diffuse map in photoshop and choosing the multiply blend mode.

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