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Script to do column to row
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MOTO(9.1) MOTO(9.1) NAME
moto - create animation scripts SYNOPSIS
fb/moto [ -fstart end ] [ -sskip ] [ file [ arg ... ] ] DESCRIPTION
Moto is a command generator tailored for an animator's needs. Its input is a concise description of the animation to be produced; its out- put is a command file suitable for input to rc or some other command interpreter. Its arguments are an optional file name containing a moto program (default standard input) and list of numeric parameters that are made available to the program. A moto program consists of a list of groups of commands guarded by a range of frames. Groups may contain parameter ranges enclosed in brackets []. For each frame, moto checks each group and processes those whose guards include the current frame number: 1,6: clr 128 1,4: clr -w [0,30] [0,30] [100,130] [100,130] 3,6: clr -w [100,70] [100,70] [130,100] [130,100] 255 This generates clr 128 clr -w 0 0 100 100 clr 128 clr -w 10 10 110 110 clr 128 clr -w 20 20 120 120 clr -w 100 100 130 130 255 clr 128 clr -w 30 30 130 130 clr -w 90 90 120 120 255 clr 128 clr -w 80 80 110 110 255 clr 128 clr -w 70 70 100 100 255 Two special guards, BEGIN and END, specify actions to be taken before and after processing frames. Moto allows complex computations inside parameter brackets: 1,10: clr [127.5*(1-cos([0,360]))] This generates clr 0 clr 29.82933350233 clr 105.35985734747 clr 191.25 clr 247.3108091502 clr 247.3108091502 clr 191.25 clr 105.35985734747 clr 29.82933350233 clr 0 Expressions may include constants and variables. All values are double-precision floating point numbers. The operators =, /, +, - (both unary and binary), <, >, <=, >=, ==, !=, ?: and !, all with their meanings as in C, except that all results are coerced to double. The result of a%b is a-b*(int)(a/b). The result of a&&b is a?b:a. The result of a||b is a?a:b. The exponentiation operator is ^, also writ- ten **. The expression [a,b] varies from a to b, linearly as the frame number varies between the guards of the group containing the expression. The expression a[b,c] has the value a*b+(1-a)*c. Its value varies from b to c as a varies from 0 to 1. The expression $i has the value of the i'th parameter following the file name on moto's command line. The precedence of operators is, from lowest to highest: = ? : || && < <= == != > >= + - * / % [ ] ^ ** - (unary) ! $ Expressions may be parenthesized to alter precedence. The following math functions are available: fabs floor ceil sqrt hypot sin cos tan asin acos atan exp log log10 sinh cosh tanh All math functions are as described in the C library, except that angles are measured in degrees rather than radians for the trig and inverse trig functions. In addition hypot may have two or three arguments, atan may take two arguments instead of one, and may also be spelled atan2. For parameterization, and to allow even more complex computations, moto has variables, assignment and computation groups. A computation group causes no output; rather its body is a group of expressions to be evaluated for their side effects. It is distinguished from a com- mand group by having a double colon separating the guard and body: BEGIN:: n=5 1,n:: x=512*sin([0,90]) 1,n: pcp -w 0 0 [x] 488 pic.[1,n] %0 This generates pcp -w 0 0 0 488 pic.1 %0 pcp -w 0 0 195.93391737093 488 pic.2 %0 pcp -w 0 0 362.03867196751 488 pic.3 %0 pcp -w 0 0 473.02632064578 488 pic.4 %0 pcp -w 0 0 512 488 pic.5 %0 Upon occasion it is useful to split moto's output into several files, under program control. A group that is separated from its guards by an at-sign @ instead of a colon names a file into which subsequent output is to be written. For example, 1,5@ file.[1,5] 1,5: This is file.[1,5]. creates 5 files, with names file.1, ..., file.5. Each file's contents will announce its name. As is true for all sufficiently large programs, moto has a shell escape. The text of a group separated from its guards by an exclamation point ! causes a copy of rc(1) to be started. The group's text is sent to rc's standard input, and its standard output inserted into moto's output. SOURCE
/sys/src/fb/moto.y MOTO(9.1)
