4.12 Halo Settings
By using halo settings, only the vertices of a mesh object will be visible when rendered (Figure 4.18). The vertices will display as points of light, which look like rings, lines, or stars, or a combination.
4.13 Vertex Painting
In addition to the options for adding materials to an object as described so far in this chapter, Blender also provides the “Vertex Paint” tool, which allows you to manually paint a material onto the surface of an object.
You can paint by changing the 3D window from object mode to vertex paint mode (Fig-ure 4.19). You will be able to paint a selected object immediately, but before you can render an image with the paint showing, you must have a material added. A new object added to the 3D window displays with the default
“Halo” is selected.
Rings, lines, and stars combined
Mirror color Figure 4.18
Figure 4.19 Specular color
Blender gray color, but, as you can see in the properties win-dow “Material” button, there are no control tabs displayed.
With the new object selected in the 3D window, in the prop-erties window “Material” button, press “Add Material.” The new object still displays in the 3D window as the same gray color but now the “Material” button contains control tabs.
Go to the “Material” button – “Options” tab and tick
“Vertex Color Paint” (Figure 4.20). “Vertex Color Paint” tells Blender to use the painted material instead of the base color when you render an image. It must be ticked before the paint color will render.
As vertex paint suggests, the process involves painting vertices. The default cube in the 3D window only has eight vertices, therefore it doesn’t provide much scope for a dem-onstration. Delete the cube and add a UV sphere. The default UV sphere has 32 segments and 16 rings, which provides a vertex at each intersection point. If you would care to count the intersections, you will find there are a lot more vertices in the sphere than the cube. You can also subdivide in edit mode to add more vertices.
Change the 3D window to “Vertex Paint Mode”—the UV sphere looks like a white disk and your 3D cursor changes to an orange circle (Figure 4.21). The tool panel at the left of the window displays with the “Brush” tab open. In the “Brush” tab, you have a circular color picker for selecting the paint color with a bar across the bottom that shows the color selected (Figure 4.22). By default, the selected color is white. To paint, click in the colored circle to select a color then, in the 3D win-dow, click, hold, and drag the brush across the UV sphere.
Figure 4.20
Figure 4.21 UV sphere
Paint brush
95 4.13. Vertex Painting
Immediately below the color bar are two sliders.
“Radius” controls the size of the brush (the circular 3D cursor), and “Strength” controls how much paint color is applied. Another way of controlling the size of the brush is to press the F key and click and drag the cur-sor towards or away from the center of the brush circle (Figure 4.23). Click the LMB when finished. The size of the brush circle changes and the slider value in the tool shelf is reset.
Besides the “Brush” tab, the tool panel contains five other tabs. Starting at the bottom:
t The “Tool” tab. Here you can select the tool specific to vertex paint and use a drop down menu for selecting the brush mode (Figure 4.24). The default mode is “Mix.”
t The “Appearance” tab. Here you can see a color bar showing the color of the brush circle. Clicking on the bar opens a color picker for changing the color of the circle.
t The “Options” tab. This tab provides settings for how the brush operates. For example, with “All Faces” ticked, the brush will apply paint to all faces adjacent to the vertex being painted (Figure 4.25). Placing the cursor over each option displays a description of the function. Unfortunately, some of the descriptions are ambiguous.
t The “Curve” tab. This tab provides a graphical method for controlling how the brush applies paint. A small graph is displayed with a curve containing control handles (Figure 4.26). The handles may be manipulated, altering the curve shape and changing the brush paint application. There are also quick select buttons for changing the shape of the curve.
Figure 4.22
Figure 4.23 Press the F key and drag the
cursor to change the brush size.
t The “Stroke” tab. This tab provides controls for brush application; you should experiment with the different effects.
Remember that although the UV sphere looks like a flat disc, it is in fact a 3D sphere. You can display the segments and rings and subsequently the vertices and faces of the sphere by activating the “Face Selection Mask” in the 3D window header (Figure 4.27). When painting, you can only paint the visible surface of the object. You have to pan the 3D view or rotate the object to paint the hidden surfaces (Figure 4.28). The vertex paint color can only be seen in vertex paint mode or in a rendered image (Figure 4.29).
There is plenty to experiment with regarding this topic and, now that you have grasped some of the basics, it’s a good idea to look at some tutorials on the internet (see the Refer-ences section of this manual for a starting point). Video tutorials pack in a lot of informa-tion and there are some good tips to be found:
Tips:
t In vertex paint, the default viewing mode is “Solid.” I have mentioned turning on “Face Select Mask” to see the mesh vertices, but you can also Figure 4.24
Figure 4.26
Figure 4.25
Select this tool for vertex paint. appears to act like an eraser.
Drop down selection menu
97 4.13. Vertex Painting
Figure 4.27
Figure 4.28
Figure 4.29
“Face Selection Mask” in the 3D window header
The visible surface is painted.
The 3D view is rotated, showing the unpainted hidden surface.
“Face Selection Mask” activated, showing segments and rings
Vertex paint mode Rendered image
switch to “Textured Viewing” to see the actual surface of the mesh while you paint.
t Click on the icon in the “Brush” tab for the quick set brush options in the
“Tool” tab (Figure 4.30).
t If you want to paint the entire surface of the mesh, go to the 3D window header (while in vertex paint mode) and select “Paint – Set Vertex Colors.” Whatever color has been selected in the brush color picker will be applied to the whole mesh surface.
t Sometimes it is difficult to see what is being painted in the 3D window. Re-member the default 3D scene only has a single point lamp in place. Therefore, you are going to have shadow that obstructs the paint view. Add some more light with additional point lamps or spot lamps (see Chapter 7 for more infor-mation).
Click on the brush tab.
Figure 4.30
The option names are hard to see.
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