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bigelectricat wrote:how about providing the option to do anti-aliased rendering? it would smooth out the edges especially of rotated objects.

chris wrote:In an abstract sense, the CFDG language is interesting -- and appropriately named -- for the reason that all design rules are context-free. (Search google for "context free grammar" if you want to learn more about that). With that in mind, we'd rather not add anything to the language that violates this principal.

For examples: passing variables to child shapes,
[snipped]

rule CURVE(@segments, @anglepersegment)
{
  SQUARE { y 5 s 1 10 }
  (@segments > 0) CURVE(@segments - 1, anglepersegment) { y 10 r (@anglepersegment) }
}

{
  SQUARE { y 5 s 1 7 }
  CURVE(4, 7) { y 10 r 7 }
}

{
  SQUARE { y 5 s 1 7 }
}

• All parameter names shall be prefixed by '@' (or some other character, or suffixed, or what have you) to disambiguate them from any parameters (some of which might not have been added yet at the time the rule was created).
• A "rule class" has a list of parameter names enclosed in parentheses directly following its name.
• Parameters have only numeric values.
• An infix expression may be specified at any place a number is expected, provided it is surrounded by parentheses.
  
  Example:

  Code: Select all

      rule RECTANGLE(@width, @height)
      {
        SQUARE { s (@width) (@height) }
      }

• If such an expression precedes a rule's name, then it is treated as a boolean which, if false, excludes that statement entirely from the generated rule. As in C, relational operators shall return 0 for false and 1 for true, and any non-zero value shall be considered true for the purposes of predication.
• When invoking another rule, if the name supplied is that of a rule class and not a single rule, then the designated number of parameters shall follow as a list, enclosed in parentheses, of expressions. These expressions need not themselves be enclosed in parentheses.
  
  For an example, see the "CURVE" rule class above.
• This could interact with the looping proposal, such that an expression followed by an asterisk, a transformation expression, and a call to another rule repeats that transformation/rule as many times as the expression denotes.
  
  Example:

  Code: Select all

      rule CURVE(@segments, @anglepersegment)
      {
        (@segments) * [y 10 r (@anglepersegment)] SQUARE [y 5 s 1 10]
      }

1. The CFDG file is parsed down to a compact set of data structures.
2. The rendering algorithm is run on these rules to produce a list of shapes.
3. And the shapes are then sent to a canvas object to produce an image.

bigdrip681 wrote:it would be cool to have the program export as a PNG without the white background I.E. Transparent.

MtnViewJohn wrote:The output of Context Free often has over a million shapes. Your hard disk would quickly fill up and Illustrator would choke. Even simple images have tens of thousands of shapes.