Piano's Final Touch

Piano's final look.

In order to make the texture looks more interesting as well as giving it more a sense of history and character, I added the remains of ripped off posters and children's handwritings on the piano, hinting that people may have been sticking random information on the piano that was later removed, and the fact that children may have played around the piano and left marker pen writings on the piano as well as damaging it during the piano's time in the town hall.

After I finished the final touch of the texture map, I decided to enhance the 3D effect further by adding a 'Bump Map'. From the advanced research I have conducted, I learnt that they are just grey scale information, which suggests the level of depth through the level of brightness in various areas. So the holes and some scratches would look deeper because they are a lot darker than other the other parts of the image. So I created an 'Adjustment Layer' in photoshop and applied a 'Black and White' filter to create the bump map.

Above images are comparison of different depths of bump.

A 'Specular Map' works in the same way as a bump map, but it effects the level of reflection on the surface instead. In other words, the brighter a certain part of the image is, it is going to be more reflective, and the darker a certain part of the image is, it is going to be less reflective.

In order to make the specular map, a few minor adjustments were required. By looking at the image, I could tell that the scratches will be more reflective than the other areas because they are brighter. However, from what I have observed, scratched wood actually reflects less light than normal wooden surfaces. As a result, I applied an 'Invert' filter over the base and the scratches layer, and then applied an adjustment layer of 'Brightness and Contrast' attempting to exaggerate the effect.

I plugged the specular maps into the 'Color' slot under 'Reflection' to make the specular map work accurately.

Ambient Occlusion

Source: By Sally Wibrew 2009 

Above are images from another PDF document Reno gave me. This teaches people how to render out a layer of ambient occlusion map from Maya and merge it together with other textures in Photoshop in order to reduce render time via cutting down the sub-shadow calculations.

Following the procedures demonstrated in the document, I rendered out an Ambient Occlusion map and 'multiply' it with the rest of the textures to produce the sub-shadows effect.

This is the final render image of the textured Piano so far. However, I still think the piano lacks identity, so I would like to find or create some images of writings, paint and water stains for example, on the piano as a final touch.

Bump Maps

Reno told me about this program called 'CrazyBump', which allows you to use one image and create a bump map through it. So I soloed a scratch layer and rendered it out separately as a targa file.
I then brought the image into CrazyBump in order to create a bump map.

The results are however always more intensified in Maya comparing to the settings in CrazyBump, so a lot of tweaking are required to get a good result.

I tried to use another layer of dirt, 'chipped marks', to create a bump map. With a setting of 50 in Intensity, created the result shown above.

With a setting of 5 in Intensity, created the result shown above. Still very exaggerated even with a very low setting.

After consulting with the director and another texture artist, we decided that we probably do not need to use a bump map for the piano due to the camera distance.

Piano Texturing 2.0

With a sample of all the dirt layers applied to one PSD (Photoshop) file, I decided to bring them to my base layer file and start building the dirt layers on top of it.

I basically bring in the particular layer of dirt which I wish to apply from my sample photoshop file and use 'brush tool', 'eraser tool' and 'stamp tool' to draw the dirt marks around the texture. With the knowledge I gained from my in-depth research, I have the awareness of painting the patterns with a sense of irregularity in order to prevent obvious repetition, which often provides a fake CG look.
Also from studying the aesthetic of texture painting, I learnt to think about the history and story of the object: Where has it been? Who has owned it? How long has it been? When was it produced? What could have happened on his journey from the production to our set, an old town hall? By answering these questions, I was able to quickly understand which areas of the object may be touched more often and hence retained more damage via different methods, and hence realise how I should paint the texture and what kind of dirt and dust layers I should put on which area to create a more genuine look.

The same principles applied throughout the entire process. This is another layer of small scratching patches and more scratch marks.

Another layer of big scratching patches and chipped marks.

When the scratch marks are done, I decided to put a layer of dust over it. Using the 'fill layer' technique I read from the PDF files, I applied 'grey fill layer' and hand painted out the area, which I think should have less dusts.

I then applied the texture file to the 3D piano model in Maya and rendered the images out at different camera distance. However, I was not very satisfied with the current look. The dust layer was too plain and lack of details.

So I decided to use 3 different images of dust patterns on the Internet in order to add the details I was looking for from the dust layers. Their colours did not match, so I did some simple colour corrections on each image via 'colour balance' and 'curve', I then merged all the images to the same layer, which allows me to access any section of the dust maps and blend them together as I wish. Again I did it very carefully to prevent the pattern repetition. During the working process, I discovered that constant change of 'brush size' and 'hardness', as well as the mirroring point while using 'stamp tool', create the best result.

The front part of the piano is going to be seen more often, so I applied two layers of dust maps on them to add another level of randomness to the texture as both layers contain different levels of detail.

This is the render of the piano with the customised dust layer on. But it didn't look dark enough.

As a result, I repainted the 'grey fill layer' I did previously so it would blend with my customised dust layer and create a more intensified effect.

From Research to Workflow

With the knowledge I gained from the PDF documents, I decided to redo the piano again.
Since I already have the base texture, I decided to build up on my layers of dirt and scratch marks from it.

I used the 'blend if' in the layer style options together with 'colour range', which I learnt from the research documents, to remove the pixels I do not need, leaving only the dark coloured scratch marks. Depending on the image, sometimes I might have to spend some time hand paint out certain areas to get a clean textures with just the scratch marks over alpha channel.

I then changed the scratch layer's 'blend mode' to 'Screen' in order to blend the two textures together. This way, I could also render out a bump map separately with whichever scratch layer that I want. However, I did experiment with various 'blend modes' to try out different effects. This quickly assisted me to gain a better understanding regarding various 'blend modes' and their functionalities.



With the same technique, I started to build layers and layers of dirt on top of the base texture. After experimenting with different 'blend modes' on this layer, I felt 'soft light' provides a more genuine look.

Base Texture.

Adding long deep scratches.

Adding short pale scratches.

Adding small scratching patches.

Adding big scratching patches.

Adding chipped marks. Final dirt layer samples.

In-Depth Research

Reno gave me a few PDF documents regarding texturing techniques in order to increase my knowledge of texturing.

Source: By Stefan Morrell from CG Society, http://stefan-morrell.cgsociety.org

Above document follows through a set of procedures from step 1 to 22, demonstrating how to texture a robot realistically with photoshop and 3ds Max. This is a good reference of the CG texturing workflow, which made me realise the importance of building up textures in layers and constantly referencing the texture maps in photoshop with the 3D geometry in Maya. I learnt an useful technique of creating the look of aged paint with photoshop from this document, too.

Source: By Leigh van der Byl from CG Society, http://www.onona3D.com or leigh@leighvanderbyl.com

Above document focuses more on the aesthetics of texturing. Basically how to give history and a sense of identity to the object you are texturing. The impact in which time, weather and human touches have on the objects being textured. When was the object created? Where has the object been? What has happened to the object? Who does the object belong to? By answering questions like these, it is not difficult to visualise what the object should look like.

Subtle things like at the edges of the object where it is touched more often should be worn off more so than areas that are less likely to be touched. Despite how obvious this may sound, small details like this is what makes a good texturing artist stand out from another.

Furthermore, analysing the surface properties to determine the amount of reflectivity, refractivity, incandescence, specularity and translucency for example, would help to achieve the optimum look when selecting the textures for particular shaders.

Source: Tutorial 2 September 2008 by Jeroen Maton from CGSociety, http://features.cgsociety.org/story_custom.php?story_id=4678

This last document discusses more in relation to the actual techniques artists may use when texturing in photoshop. Techniques like using 'unsharp masks' to sharpen the images to get a crispy look on the textures, using 'blend if' to exact certain parts of an image to fuse it together with the base texture via different blend modes and applying a fill layer at the top while paint out certain areas to create the look of dirt or dust layer for example.
Although there are only a few techniques being illustrated in the document above, but just by familiarising myself with the techniques shown above, it has already helped tremendously with my texturing workflow as well as broadening the options of my working method.