week 12 - optimising, retopologising and baking a texture onto the model

After I have built an Ice crystal formation out of only modular elements, I came up with a really nice final product, but it had too much information, too many polygons were hidden and hence unused, so that was basically overloading the system unnecessarily.

These are the 2 basic crystals initially created.

Using them and scaling, rotating, moving and duplicating, I have achieved 3 separate Ice crystal formations to be used in one of the levels of the game to be released. 

Here are the renders of the elements created. 

Ice_Crystal_03_MESH

                           

Ice_Crystal_02_MESH

Ice_Crystal_01_MESH

However, as I mentioned before, in order to be included in a game aimed to be released on Ipads and Iphones, I needed to reduce the information and I have retopologised the meshes.

The first one I have started with, was Ice_Crystal_03_MESH, and for doing this, I have used the Freeform option, and PolyDraw with step Build. This basically, allowed me to recreate polygons using the outer surface of my model created, ignoring the information not needed form the inside.

So, my actual final model to be used in the game looks as the following image will show, and the difference is, not so much in the look of it, but in the number of polygons, significantly reduced (from 229 in the original model, down to 138 in the final one).

Ice_Crystal_03_optimised_MESH

Here they are, side by side, just to give a better idea of the differences (or lack of them) in visual aspect:

Ice crystal 03 original and retolopgised (optimised)

Next step, was unwrapping and texturing. 

The unwrapping was a little bit complicated due to the number of faces and angles the object has, but in the end, my UV looked like this: 

As I said, it might look some how untidy, but in order to keep the original shapes, I wanted to keep it as organic a s possible. And by doing this, I managed to keep the stretching of polygons to an absolute minimum. Here's how the checkered map looked on the object. :

Ice_Crystal_03_Optimised_MESH

Before starting the texturing process, I was advised to do a "bake" of the model, in order to pick up the details and have a starting point for my texture map.

It was the first time I have actually done a "bake" so, here are the steps that I have followed:

First, I have selected the model and applied a white material to it from the Material Editor in 3DS Max.

Then I have introduced a skylight in the scene, in order to create ambient occlusion and obtain realistic shadows.

Then, by opening the Rendering menu from the top bar of the screen, I have selected the Render to Texture option. This opens a window with a lot of parameters to chose from, so a lot more options. the basic ones that I worked with, were:

Output - I have selected where my rendered image will be saved

I have then ticked the option below this, which said Rendered Frame Window

The next element is Objects to Bake and if the element is selected, then under Name, my element name already appeared( Ice_Crystal_03_MESH).

Underneath, the Padding is set to 2 by default, and for a 512 x 512 texture, that should be enough, as padding is basically "The amount, in pixels, that edges are allowed to overlap in the flattened (“unwrapped”) texture." (3DS MAx Help)

Next step, in the Output section, the file name should already be displayed. Underneath, there is an option "Add", by clicking on that, there are several texture elements available to chose from. I have chosen BlendMap, as I only want to do a basic texture bake.

Next, I have chosen the size of the map, and I have chosen 512 x 512.

I have changed the Black default Element background colour, to a light blue, as I would find it really difficult to work on a black background in Photoshop.

And the baked map looks like this: 

Bake map

The difference between this render and the previous one is the slight shadow detail added, which can be used on the UVW map.

At the bottom of this window, there is the Unwrap Only option, which, if chosen, it will render only the UVW map with the baked information on. And that will be the starting point for the texture map in Photoshop.

This is how my baked UVW map looks like: 

baked UVW map