Online Help for Chasys Photo

Automation : Syntax

What is Syntax?

Syntax refers to the formatting rules that need to be followed when writing a script. The use of syntax ensures that Chasys Photo will correctly interpret the script.

Syntax Rules

A script is made up of a list of instructions called statements. Each statement consists of a keyword (a command), parameters (if required) and a semi-colon at the end. For example, the second item in the list below instructs Chasys Photo to perform a rotation transform with angle as 45 degrees:

fx_synenhance;
xform_rotate 45.0;
fx_spinblur 30.0 12 12;
xform_skew 30.5 horz;
xform_flip vert;

A script may contain descriptive text; these are called comments. The starting point of a comment is denoted by two forward slashes. The comment spans the rest of the line it appears on:

//This is a comment
fx_synenhance;
xform_rotate 45.0; // This is another comment
// fx_spinblur 30.0 12 12; --- This is also treated as a comment even though the text seems to be a valid command
//The same applies here .. xform_skew 30.5 horz;
xform_flip vert;

Chasys Photo ignores comments when it is executing the scripts.

The semi-colon at the end of the statement is mandatory. The semi-colon is not required for comments.

Document Conventions

The parameters used by some commands may require special formatting; this information is conveyed in the documentation using format specifiers as shown below:

Format Specifier	Meaning
#color	Color value. Colors are specified using 32 bit hexadecimal digits padded to 8 symbols and preceded by a hash symbol "#". The lowest 8 bits are for blue, then green, then red, and finally alpha in the highest position. For example, R=0 G=128 B=255 A=192 is expressed as #c00080ff.
"string"	Quotes string. The parameter is a string that may contain any character except return, new line and double quotation marks. The start and end of the string are denoted by double quotation marks.
...	Variable list. The number of parameters is not fixed.

Some parameters may only accept certain values or ranges of values; this information is conveyed in the documentation using range specifiers as shown below:

Range Specifier	Meaning
[0..360]	Numerical range. Any numerical value between and including the indicated numbers may be specified. For example, when [0..100] is indicated, you may specify a value like 64.5.
[horz, vert]	Option. You may specify any one of the indicated values. For example, you may specify "horz" or "vert", but not both.
[r\|g\|b\|a]	Color channel flags. The parameter is a set of flags that may be combined to indicate which color channels to use; e.g. "rg" means "red and green".
[1\|2\|3\|4]	Numerical flags. The parameter is a set of numerical flags that may be combined by addition; i.e. to specify item "1" and item "2", set the parameter to "3" (i.e. 1+2). Normally used for color-channel specification such that B=1, G=2, R=4 and A=8, so that if you want to set R and B you specify 5, i.e. 1+4.