At the moment the whole object “dressed” the same color, varying only the illumination effect on its surface to provide the sense of volume.
The textures add a component of credibility to objects, practically only the lack add shadows to position in space.
Texture is the property that have external surfaces of objects, and sensations that cause, which are captured by the sense of touch. The texture is sometimes described as the ability to feel tactile sensations ( that are not captured by the hands). (W)
In this case we will add images on the surface of objects; a skin that brings new visual effects.
Start from a simple scene as always, so that we can experience and see the results immediately, strengthening technical learning.
A ground plane which serves (on which it can cast shadows) and a pair of single volumes (cube and sphere) illuminated from two points “light” omnidirectional scene elements used for this analysis.
When rendering the scene we see that, if not defined Material, objects have the same surface appearance. The contours may be confused or emphasized depending on the intensity of light in the scene.
The image information is based on differences in intensity of light falling on each point of the surface.
We emphasize this point because the final image is done by fusion of light and color. Observe how lighting affects not apply textures gives an idea of the intensity or strength of the different parts in the whole composition.
We will make several changes to the textures to understand the mechanism by which, varying the different parameters and observing the result.
To change the material of an object and add textures and select the corresponding object will first add a generic material. This material contains the color information, transparency, reflectivity and textures that will determine your final appearance.
In the Controls window, after selecting the edit mode materials, we can add a new button material “Add New“.
Immediately appear a set of windows that allow you to customize the material.
In particular we are interested in the window “Texture”. We will see a number of empty boxes and controls on your right.
The rectangles in the figure represent positions where we can add new textures. The window textures must be in an initial state with no texture defined. The final composition may contain different images thus superposed on each surface.
Clicking on “Add New” add a new texture to the material that will be reflected in the “pile textures”. The mark on the left of the texture (“Tex”) indicates that it is active.
On the right side of the window have a new button to delete the texture, “Clear” and a region with the texture name.
The textures are named automatically, but we can change the name simply by clicking on it and entering the corresponding text.
Choosing a suitable name can be useful later, but for our immediate goals is enough to know that this possibility exists.
The new texture is not yet defined. We generated the data structure required for storing and handling, but we have not indicated their content.
You can use a set of parametric textures included in the program as well as image files and scripts that generate new still or animated images.
You will see two sets of windows:
- Preview, to give us an idea of the texture chosen
- Defining the type of texture (“Textures”).
In the dropdown menu you get when clicking on “None” We can choose this option.
At this point define the type of texture (“Texture Type”) and we give way to establish a new set of values to customize the texture.
These adjusted values resizing texture and other factors that will be analyzed at the time.
The choice we have made gives us a regular pattern of black and white lines.
Actually applied to the object a pattern of lines that are then to be selected color, Texture “draw” on the surface of the white region with the chosen color.
For an approximate effect of the result in the 3D window of the application, change the display mode:
The object has been superimposed illumination color and texture chosen initial, that has “painted” a default pink, since we have not changed any color so far.
The result is shown below in rendering. The object has moved from a “color plano” a first “superposition” colored.
The textures are applied and defined in this simple example. With these simple elements and playing with the parameters, can make interesting images that illustrate the richness they add to the creation of synthetic images.
Before you begin to detail the parameters that govern the textures, encourage the student to explore these techniques independently for a short time. To try to make changes to the parameters and observe the results as a form of playful approach.
For example, the use of texture to simulate a semitransparent object
Feel like experimenting with textures?
Tutorial made for version 2.49b