Datasheet

53
CHAPTER 1
CHAPTER 2
CHAPTER 3
CHAPTER 4
CHAPTER 5
CHAPTER 6
CHAPTER 7
CHAPTER 8
CHAPTER 9
CHAPTER 10
CHAPTER 11
CHAPTER 12
CHAPTER 13
CHAPTER 14
APPENDICES
INDEX
disrupting the smooth surface. When prims overlap improperly, the textures on the overlapping prims
may “fl icker” as they fi ght to decide which texture is on top. When you build by the numbers you use
some simple math to position and size your prims perfectly.
■ THE M WORD (MATH)
For our fi rst example, we’ll build a 20-meter-long wall. As you know, the prim size limit is 10 meters,
so we will have to use two prims.
1. Rez two prims and enter the following size values: X = 10.000, Y = 0.500, and Z = 5.000.
2. Copy and paste the Y and Z position values of the fi rst wall over to the second wall.
This will line up the two wall segments on all but one axis.
We don’t want the same values for the X position on both wall segments; that would cause both
wall segments to occupy the same exact space! Instead we will do a little math so both prims are
precisely side by side.
3. Find the length of the fi rst prim (the x-axis size) and divide it by two. (That’s 10 ÷ 2 = 5.)
4. Find the length of the second prim (the x-axis size) and divide it by two.
(That’s also 10 ÷ 2 = 5.)
5. Add the two together. (5 + 5 = 10.) You now have the offset.
6. Find the x-axis position for the fi rst prim, add the offset of 10 to that value, and paste the
result into the X position for the second prim.
If you did everything correctly you should have two wall segments sitting side by side. There will
be no gaps and no overlap. It’s mathematically perfect!
■ USING SNAP TO GRID
Another way to build precisely is to use
the grid and the Snap to Grid option.
The Use Grid option is found in the Edit
window along with an Options button
that allows you to control the details.
To use the grid, grab the planar drag
handles (the little triangular move
handles) for the axis along which you
wish to move. A white grid will appear
around your prim; the grid includes a
solid white line that represents grid
units, and fi ner lines that represent
sub-units. You can toggle Snap to Grid
mode by pressing G or going to Tools
▶ Snap to Grid. Snapping to the grid
is a lifesaver when it comes to allowing
you to set precise positions without
having to do as much math.
By setting the Ruler mode in the
Edit window, you can chose between
using the global grid, which is based
on global coordinates, and local grid,
which adjusts the grid to fi t the prim’s
current position. You can also elect to
Figure 3.16: The Grid Options window
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