Texturing mentor

In this topic we will work on scorched, dry and barren landscape made up only of sun hardened mud which breaks up into big chunks which further breaks up in to random pieces. The background is made up of a simple gradient which has been randomized a bit by using the built in noise with a low frequency. The tree is a poly converted paint FX tree. The entire scene is illuminated by two lights. Create a scene with an uneven nurbs surface. The scene contains an uneven nurbs surface with a paint FX tree. The background is simply a randomized gradient ramp applied in camera’s environment.

As you know the usage of shadow casting light, we will now bake the lighting and shadows in to a file. Create a new lambert material and set its diffuse color to white. Select the surface and the lambert material’s shading group node and go to hypershade > edit > convert to file texture options. Enable the bake shading group lighting bake shadows and set the X and y resolution to 1024 and file format to wither default or any other format like TGA. Now click on convert and close. As you can see the lighting is now baked into a file texture. You may now delete the light and render. You will see that the lighting is still here, thanks to the baked up light map.

In UV terms, each face is mapped to the 0 to 1 texture space; hence it quickly simulates a tiled look. Select the surface, go to polygon UVs > unitize option box and enable the create new UV set option. Set the name to tiles and click on apply and close. As you can see the texture map tiles perfectly to our plane surface. Now we want to add a little dirt to the texture by layering a dirt and grime map. But we want this 1k map to be applied to the entire surface rather than unitized to each face. To achieve this, select the plane, go to polygon UVs > planar mapping option box and use the create new UV set option to create a new set called dirt.

Apply a layer mask to the concrete layer and use the cloud filter in it. Since the cloud filter produces a grey scale pattern, it lets us see through the concrete layer. To make things clear and interesting, keeping the layer mask selected, go to image > Adjustments > Threshold and adjust the settings till the time you get a good chipped off concrete look. Once you have got the basic look, use burn on the concrete layer to create, grime marks around the chipped areas. Also, use layers, paint with black and use smudge ti create water stains and more dirt and grime.

The layered texture in Maya opens up a lot of opportunities when designing a shading network. In the example, we will also bake lights a process of converting illumination and shadows into a texture. This is very widely used in the gaming industry to reduce processing overhead of real light lighting. Create a plane of 4 *4 divisions. Add a spot light with depth map shadows enabled. First we will design our basic tiles look. Create a lambert material and connect a new file texture. As the texture requires tiling, we can use repeat UV option in the placed 2d texture node. But here we will use a different technique called as unitize UV’s. This option maps the texture individually to each polygon face of the geometry.

Next, we will add a text layer which says ‘no parking’. To make it more interesting, use a blending mode and apply a layer mask. Paint with black on this layer mask using a brush to erase off areas of the text. This method ensures that the text stays vector and editable and still give a feel of being painted. To create a bump map, convert this image in to grey scale and use levels to tone down the luminance on the concrete layer by using levels. Save it out as a bump map. Finally in Maya, apply the color map as a texture to the color attribute of the shader and the bump map with a value of -30 using bump 2d nodes.

Adobe photoshop is your biggest ally while creating a texture. While bitmap texture occupies more RAM, the sheer flexibility of an image editing application makes it easy for us to create to make great textures. In this example we create a dirty wall texture in photoshop and apply it in Maya. Create a 2048 x 1024 size canvas in photoshop and import two texture files, one for concrete and the other for brick. If the textures are of smaller size than of the canvas, duplicate the layers; merge them and clone stamp out any edges. Ultimately you should be left out with just two layers, concrete and bricks underneath it.

Set the gradient map’s type to U Ramp. To create the fine grain observed on a cd, map a fractal to the bump attribute, set the bump value to 0.001 and the repeat UV of the fractal to 40.0000 and 40.000. Create a label for the cd and map it on the other side of the disc as seen earlier using a layered shader. Create a vinyl record if possible. While creating a cd texture at most care should be taken. It’s an easy task, but I’ve seen many people getting struggle while creating the cd texture. So just practice this and get used to it. And disprove the quote ‘creating a cd texture is no cake walk’.

Create a compact disc by using two tube primitives, one for the Cd’s write layer and the other for the plastic mould or open up the same file. For the outer plastic layer, simply use a blinn shader with a low specular color and 98% transparency. For the Cd’s write layer itself, drag a new anisotropic shader into the workspace and set the color to 40% grey. Next for the specular highlights set the roughness to 0.575, fresnel index to 9.008. To give the unique multi colored highlights as usually observed in a cd, drag a gradient from the 2D textures category and map it into the anisotropic material’s specular color attribute.

A compact disc demonstrates a most unique form of specular highlights known as anisotropic highlights. Anisotropy or anisotropic material has vertical or radial grooves in the surface as such as brushed metal, old vinyl records and a compact disc which has tracks in the form of pits and lands burned on the surface. These produce a unique linear highlight as opposed to a circular highlight as demonstrated by a typical surface or in CG a phong or blinn shader. Therefore to simulate a linear highlight we can use an anisotropic material.

The layered shader works very much like layers in photoshop where the materials on the left go on top of the ones next to it. Therefore label goes to left of glass. Now drag and drop the label materials into the layered shader’s transparency attribute. For positioning the label, use its placement node coverage and translate frame attribute. In this case we are using coverage U,V values of 0.344 and 0.424 and translate frame’s UV values of 0.32,0.310 . For simulating reflections as on a wine bottle, we are using three planes with their color and incandescence set to white so that it acts as our source of area lights. Render using Mental Ray.

Create a lambert shader and call it label. Create a new file texture node from the 2D textures category and connect the file texture to the lambert’s color attribute. Next connect the file texture’s out transparency to the transparency attribute of the lambert. In the file texture node color balance section set the alpha gain to 2. Now that both our materials are ready, we’ll layer them to finish the material. Drag a layered shader in to the workspace. Now drag and drop the glass material created earlier into the layered shader palette. Next, drag the label material into the layered shader palette.