Why do I need to include settings method in my sketch
Since processing-3.0 that is where processing expects you to set size/mode/smooth/full_screen, if you are using processing ide this gets hidden from you.
How do I set sketch title
Use sketch_title method (in setup or draw) uses surface.set_title under the hood
The jruby-complete jar is not included in the jruby_art gem
Unlike ruby-processing no sketch absolutely requires jruby-complete, providing that you have an installed jruby. The size of jruby-complete would make the gem too big to be distributed by rubygems, and k9 --install is all you need do install jruby-complete and the examples.
Why do I keep getting these warning messages when I run jruby_art sketches?
array_2d.rb:20 warning: ambiguous Java methods found, using background(int)
array_2d.rb:25 warning: ambiguous Java methods found, using stroke(float)
This is because you are using an overloaded java method, ie one that takes more than one type of argument. Background for example can also take an PImage as its argument, and stroke an int. Generally you should not worry about such messages, as jruby makes a sensible choice for you ( it is just being noisy about it ).
Can I avoid getting messages about overloaded methods when calling java?
Yes you can provide signature-specific aliases for overloaded methods, for frequently called methods this might be worth doing, as it reduces the 'overhead' of the look up calls. But for the sake of simplicity, we've not bothered, but there is nothing to stop you though.
# signature-specific aliases for overloaded methods
java_alias :background_int, :background, [Java::int]
java_alias :fill_int, :fill, [Java::int]
# using alias in place of regular method
background_int 0
fill_int 0
Can I export my sketches to javascript, coffeescript?
Absolutely not, this is a feature of vanilla processing (which is antlr parsed code). Here processing code is treated as if it were java, making use of jruby to integrate it with ruby. Nothing to stop you from inventing some cool parser, interpreter, whatever.
How do I ensure that ruby-complete is used to run a sketch
Set config JRUBY: false, you need to this if you have not installed jruby locally.
Why is there a difference between using jruby-complete and the system installed jruby
There are some security differences, that affected ruby-processing, but do not affect JRubyArt thanks to use of data_path to provide absolute path to the data folder.
How do increase the memory limit?
Create a 'data' folder if you haven't got one already in that folder create a file "java_args.txt" add the usual jvm command line options to the file eg
-Xms756m -Xmx756m (if using jruby this gets converted to -J-Xms756m -J-Xmx756m under the hood, note since jdk7 the limits may already be higher, and limits should not set lower than the default).
You can also set java_args: -Xms756m -Xmx756m in config.yml but local "java_args.txt" overrides if present.