Difference between revisions of "HowTo:Use macros and loops"
Jump to navigation
Jump to search
(New page: == Loops == Loops are usually created to do one set of code thousands of times. The beauty of the loop is that the code can reference an array or a spline to write a rollercoaster track or...) |
(No difference)
|
Revision as of 23:46, 7 December 2007
Loops
Loops are usually created to do one set of code thousands of times. The beauty of the loop is that the code can reference an array or a spline to write a rollercoaster track or a roadway such that very complicated scenes can be created with the use of simple structures.
Loops may be constructed through the use of the #while statement. A typical loop may be constructed as follows.
#declare step = 0; #declare steps = 100; #while (step <= steps) #sphere { step*x, 0.4 pigment {Blue} } #declare step = step + 1; #end
Nested loops may be created to generate a two or three dimensional aspect to the scene. Beware that creating extra nested loops will dramatically increase the parse time for the scene.
The following nested loop will draw a series of Blue balls on the XZ plain
#declare xpos = 0; #declare zpos = 0; #declare xfinal = 10; #declare zfinal = 10; #while (xpos <= xfinal) #while (zpos <= zfinal) #sphere { <xpos,0,zpos> 0.4 pigment {Blue} } #declare zpos = zpos + 1; #end #declare xpos = xpos + 1; #declare zpos = 0; #end