3D Animation, Efectos: Create a Halo [Blogs experimental][ Blender ]

A halo can be classified within the lighting elements, or be considered a special effect.

We have seen an example of use of this technique as in the case of Halo of the Sun; we will see how to define and how to adjust some of its parameters.

The classification makes sense for the organization of the software interface, so that we can structure the menus and edit simple models.

Un halo brings light and form in the scene, so your variables will be found associated with this feature.

In asking What is a Halo? can respond from a study of color, or from a point of view geometric.

The approach depends on the use we want to make this utility available animation software used for the Blender tutorial. See its extension using curves, incorporating studying lighting effects to which we referred earlier.

Mode activation “Halo”

Let us first see how you can use the vertices of the geometry for visual effects animation tools available in Blender. Activate the corresponding calculation mode and adjust the parameters associated.

Any geometry can be displayed with different display types: softened, faceteada, Wired, halo… In this composite image of four identical spheres can be observed.

Different models to represent a sphere

To select the rendering mode type “Halo” we must first access the tabs corresponding to shading, namely, in defining the material properties of the object you are editing.

Different calculation steps , to obtain an image are highly structured in what is known as “graphic channel” or “graphics pipeline“.

Tab “Links and Pipeline” there are buttons that control the “Render Pipeline“, namely, how the image is rendered.

The button “Halo” must be active (lobbied) to use the vertices surfaces like particles emit a light spot.

If you activate button DICHO, object surfaces are represented, nor its edges. Only take into account the mesh vertices that define.

All vertices of a mesh will be activated in the same mode of representation. We will have different parameters to vary its visual presentation.

Halo Variables

When selecting the “Halo” appear new controls on the tab “Shaders”.

They can be more or less numerous depending on options or modes of calculation that are active.

These windows are contextual, adapting their controls based on the options available in each case.

Flare, Rings, Lines, Start… are effects that can be applied together or independently. Its effects accumulate to produce large number of variants of the halo effect.

We see two distinct regions on the tab “Shaders“:

• Elements possible to vary the parameters Calculation (left)
• Calculation modes (right, as buttons)

These controls are used to select the different modes or combinations of modes and for different parameters that govern affects both the intensity and the form which produces the halo around each vertex.

As we have seen the edit add a material, to adjust the parameters, we can use as a reference the preview window; select the simulation that best fits our model. This window will give us a rough idea of ​​the results that we will get to make the rendering of the scene.

Consider separately each of the modes and then analyze their combinations. For this, we can use a simple object like a cube. If we observe the effect on an individual on a single point, we remove the vertices needed to stay with one. (in edit mode select all but one and press the key “X“, then confirm that you want to delete vertices dichos).

Size

The size depends on the parameter “HaloSize” that is in the flange “Shaders”; high values ​​originate halos of larger diameter than lower values.

Flare (Flare)

Flare provide a series of circles with their centers aligned. Simulate circles effects produced by a lens (optics such as photo cameras) the approach to the vicinity of a light source.

We will have a new set of parameters to control this effect, among which defines the number of sub-halos which occur (Flares), and propagating in a direction mainly.

The seed (seed) will get Variations of this effect, increasing variability with different shapes and colors for the halo. We will have many more different effects by selecting different values ​​for this variable.

Rings (Rings)

Contribute a number of concentric rings. The colors alternate with different spacings between the circles. The variable Seed allows for different groups of effects.

The base construction is the circumference halo, as a representation of a phenomenon that occurs centered on a point.

Lines (Lines)

Add lines departing from the center, like the spokes of a wheel.

The distribution of the lines is performed more or less regularly, distributing more concentrated in some directions.

The number of lines can change their distribution manipulating the seed parameter (seed) allow us to choose between different pseudorandom patterns.

The color used for lines, halo rings and may be different.

The flange “Material” change its content in the time indicated that represents the geometry of the object using the mode “Halo”. In particular the labels associated with the colors.

It can be seen that the colors do not match the common properties color “material”, “diffused light” and “reflected light” as usual, but the names associated with “color Halo“, of “Lineto” and Rings” (rings) since these properties affect the new rendering mode.

There are other features of the halo less used but interesting that comment from a descriptive point of view then. The reader should experiment with them to deepen your study.

Star (Stars)

Assign a the halo star shape.

Number “tips” of the star is determined by the value of the variable “Star” of flange “Shaders”. By default generates a four-pointed star.

Halo Tex

Lets make the halo used as the basic color of a texture, rather than that defined in the flange “Material” as seen above.

If we vary the texture or any of its parameters in animation, the halo change color dynamically, providing effects of great interest to the scene.

HaloPun

Specify the halo size according to normal at each vertex. The small flat shapes and sizes will increase as the curvature will get bigger.

In the example we have used a plane with a deformed corner which shows the “Size” Light points.

X Alpha

This function transparency effect intensifies the halos.

We can associate a texture to change the channel “Alfa” transparency, is especially useful for some purposes in particle systems:

Fire, smoke, etc..

Last, discuss two additional functions such as “Shaded” allowing halo intensity and the color look affected by shadows that throw objects, and the role “Soft” that smoothes the intensity Halo.

We will see some examples of application.

¿Was the ANIMAS experience changing variables and mixing effects?.

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