Game Texture Development - Spellbook

Recently we were given the task of modelling and unwrapping a spellbook, ready for texturing in Adobe Photoshop. I started this task early and so did not have the original spellbook model as a reference point. In spite of this my mesh turned out to be very similar but with a couple of extra details on the spine of the book.

Starting out the modelling process with a polygon primitive cube, I extruded detail into the mesh adding edge loops to give me more geometry to work with. Pushing and pulling vertices around using the move tool gave way to a more interesting silhouette for the book, well as interesting as a book can get anyway. Once I was happy with the model I then looked at any unnecessary geometry, removing it with the target weld tool or CTRL deleting the edges and multi-cutting tris into place.

Then came the UV unwrapping of the asset. Some more complex models can be difficult to unwrap by selecting individual face of the model. For this reason I always to a camera based map of the whole asset, allowing me to split the UVs into manageable parts using the UV editor. Once the UVs are organised, the selection of the UV shells can easily be converted to face selections and re-mapped. Once the UV mapping is complete you can then use the smooth UV tool to unfold the UV shells. The unfold tool can also be used for this but I find that the smooth UV tool gives you more control. Looking back I should not of overlapped the UVs for the front and back cover of the book, this would have given me the ability to have different textures on each cover.

When opening a UV map in Photoshop I always insert a colour fill layer, this makes sure that there are no transparency values in the image. Unless of course you want the alpha values to carry through to Maya. Having a mid tone gray background also helps you to recognize the tonal values in your painting much more clearly.

Introducing the textures for the book cover, pages and metal clasps just by dragging and dropping from folders into Photoshop. For the leather image there were too many specular highlights, to tackle this problem I inverted the image and colourised it. The levels were then slightly altered until the desired effect was achieved.

More detail was added to the texture in the form of text with bevel and emboss values, ware marks and shading. To get the worn effect I added a worn leather texture to the document, making this a clipping mask to a new layer underneath it. Using a custom brush I then painted with a black colour value and a custom brush. This meant that the texture would only show through in the places that I was painting. The same effect could have been achieved using a layer mask.

So looking at the finished product I can say that I am happy with it for the most part. The clasps were added late in the process and so not much texture space was left for them, this could have been prevented with better planing before modelling. What this means is the clasp texture has a much lower resolution than the rest of the texture for the book. On the whole I believe this was a successful exercise and I have taken something away from it. Thanks for reading and have a good one.....