Online Learning/ MAT

Reflection:

What photoshop and texturing skills have you learnt so far?

So far, I have learnt how to create my own UV unwraps for my 3D objects, assigning planar, cylinder and spherical UVs. Recently, we have also learnt how to unfold a UV.

With regards to Photoshop, we have learnt the basics, including how to create FX layers, masking, and what the different tools in the software do

Skills I would like to improve

I would like to improve my ability to blend colours in Photoshop, as I believe it will improve the artwork I create in the software. I can develop my skills in this area of Photoshop by watching online tutorials and by attending Gareth’s workshop sessions.

MAT:

This blog post is about creating our MAT characters. MAT is a downloadable 3D character which is used to help learn about texturing in Maya. As part of this project, we are creating our own MAT characters whilst learning about PBR (physically based rendering).

By the end of this term I would ideally like to have made a couple of MAT characters which allow me to practice making different kinds of materials. I would also like to learn how to texture one of my MAT models to achieve a cel shaded look .

Week 1 – Introduction to MAT

This week we designed our MAT characters and added textures in Photoshop before exporting them as Targa files.

Once I had opened the MAT Maya file, my first step was to select the head of my MAT character and open the UV editor. Next, to be able to open the UV in Photoshop, I needed to take a UV snapshot. I did this by selecting the camera icon in the UV editor.

annotated image — Initial idea for a MAT character

Week 2 – Normal Maps

What are normal maps?

Normal mapping is a technique that is used to fake the lighting of bumps and dents. It is traditionally used to add detail to low polygon models while maintaining the illusion of a high polygon model, which enables developers and artists to add more detail to models without sacrificing performance in game, reduces render times and saves poly count.

Most effective to convey tiny details in the model where we wouldn’t want to use a lot of polygons.

samus

If we turn off the normals and smoothing groups in any 3D software, a mesh like a sphere which we would expect to be smooth looks like it’s made from tiny polygons and like a disco ball. This is because without normals, each polygon or tri is treated with its own individual plane, meaning that lighting will effect the entirety of it without considering how it transitions between or across neighbouring parts of the model. This can be useful for items where you have drastic areas of sharp details (weapons, electronic devices with lots of buttons).

Types of normal maps

There are essentially three types of normal maps:

types of maps

We are focusing on Tangent Space, as this is commonly used when designing video game characters. Tangent space normal maps are based on the direction of each face.

When designing normal maps, we traditionally use red, green and blue channels to signify height information.

Red = left and right
Green = up and down
Blue = flat

We use 100% blue, 50% red and 50% green as a base as it allows us to go up, down, left and right equal measures when making our textures.

Making normal maps in Photoshop

The first thing I needed to do was select my MAT model in Maya and open the UV editor.

uv editor screenshot

Next, I took a UV snapshot with the following settings:

uv snapshot

With my UV file saved, I then opened Photoshop and created a custom preset, ensuring that my width and height were set to 2048 pixels (same as my UV file), the resolution was set to 300 pixels/inch, and that the colour mode was set to RGB colour 8 bit.

Having made a new layer, I went to ‘window’ > ‘colour’ in order to access my RGB colour settings. With my colour window open, I set the red and green values to 128 and the blue value to 255, as we use 100% blue and 50% red and green. With my base colour made, I then selected the paint bucket tool to add this colour to my layer.

colour

After inserting my UV map into Photoshop, to make the UV more visible I selected the transparency lock on my layer and using the brush tool, went over my UV in white.

Next, I made a new layer above my purple layer and below my UV layer to draw my design on.

capture

With this completed, I hid my UV layer and then went to filter > 3D > generate normal map and adjusted the settings accordingly.

Next, I saved my document as a PNG, and I was then able to open my MAT file, add a lambert material to my MAT character which I then added my file to. I then selected the bump mapping option which I set to ‘tangent space normals’.