Advice and things to note.

• Jerky animation. There seem to be some problems running on Samsung Galaxy S. The animation can be slow and very jerky. To get round this (and if seen on any other device) set the “smoother animation” option in the Preferences. Note that this uses more battery but only when you are animating.

• App stopping. More worrying, also on Galaxy S (the original, now ancient, S), is an occasional hang up of the program for a second or so. Once in a while this can last for 15 or more seconds and lead to the phone re-booting. This has been reported to Google and their only response was “it’s fixed in Honeycomb”, which isn’t much help! It is a rare condition – 99%+ of definitions never get it, and in the maybe 1% of definitions I create it can occur but may not happen for days at a time. It seems to be a very subtle timing thing – if a definition displays the 1 sec hang warning behaviour – be wary! The only thing to do is to modify the definition – adding or removing a source makes it go away, or else simply do not animate that definition. It has not been seen on HTC Wildfire or on Asus Transformer, but it could potentially be on some other phones, as it’s a bug in Android. To put this into perspective, out of about 1500 downloads, I have had just two ANR (app not responding) reports in 18 months.

• Speed. In both versions, the animation attempts to run at 30fps. It can manage this on most phones with 4 or so sources. A number of things have a big effect on speed:
  • the most obvious one is the size you are working at - changing from full-size animation (1000 pixels), on a tablet, say, to 2/3 size will generally result in noticeably faster running. The Asus Transformer is an excellent and powerful Android tablet but even it can struggle if you try to show animation at 1280*800 pixels. Animating at 3/4 size (750 pixels) instead is much easier as the app needs to calculate and draw less than one third the number of screen pixels.
  • some modes are slower than others - target and avoid are definitely slower.
  • in SourcesPro the use of optimizations will have a big effect on image quality but will also can have a marked effect on performance. "better waveforms" generally has little speed penalty, "++circles" and "++sweeps" have a moderate effect, but "smoothing" can cause quite a slowdown. Optimizations are designed more for generating high quality images for export, rather than for general exploring or playing.
  • the more sources you add the slower the app will run. As you add sources initially there will be no effect, since the 30fps "cap" will hide slowdown, but at some point the frame rate will fall below this and the changes will start to become noticeable. If you want animation - 5 or 6 sources is usually sufficient for even quite complex designs. If you want only to generate large still images, then add as many as you need.

• Examples. Most of the Examples provided have an interesting variant - just hit the "undo" button when you have loaded one.

• Epilepsy Warning. Sources, by its very nature, can produce complex moving patterns and it's impossible to predict programatically from a definition how it might appear when animated at any particular speed. Therefore, the warning below is shown (by default, and can be disabled) whenever the program starts up. If you feel that you are, or may be, susceptible to such effects, then do not download the program. Having said that, the vast majority of definitions show no flashing behaviour. (There is one example provided with SourcesPro - "flashing".)

"This program is designed for the creation of images and animations and it is normally completely safe, but it is possible to use it to make flashing patterns. Some people are susceptible to epileptic seizures or loss of consciousness when exposed to certain flashing lights or patterns; some may have a seizure while watching television or when using particular computer programs. This may happen even if you have no previous medical history of epilepsy or seizures. If you, or a member of your family, has ever had symptoms relating to epilepsy when exposed to flashing lights/patterns, you should consult your doctor prior to downloading or using this program. Do not use the program close to any possibly susceptible person or allow them to use it. If you feel unwell at any time when using the program, stop and consult your doctor."

• Upgrading to Pro version. If you move from the Lite version to SourcesPro and have any definitions that you would like to transfer then the method is as follows. Please note that you need to do this once only.
• first of all start up your old App - SourcesLite. Bring up the App menu, click on More, then click on "Save defs to External". This copies your definitions from internal, publicly inaccessible, storage to "external" storage - generally some form of SD card.
• Shut down SourcesLite - you are finished with it now.
• start SourcesPro and make sure you have at least one definition in your "Open..." menu. The automatically created "-AT_EXIT-" file is fine, or else just drag a single Source into the working area, click on "Save" in the menu and that is sufficient.
• You want to make sure that the external files and directories are set up for SourcesPro, so click "More..." then "Save defs to External", just as you did above.
• Shut down SourcesPro.
• If your device has a file manager then you can proceed without attaching your Android device to your computer.
• Assuming no file manager program, plug your device into its USB cable and plug that into your computer. What happens next may vary - in some cases you will be prompted to decide what to do, in other cases you will see an icon appear in your notification area which you can click on. There will in either case normally be some kind of option to "connect to PC", "mount SD card" "SD card as Disk drive". Check the instructions for your particular device. (For example, on the Samsung Galaxy S a "USB connected" notification appears and when you open this there is a "connect storage to PC" button.) Connect using the method appropriate for your device. On your PC navigate to the drive that represents your attached Android device - in my case it appears as "Removable Disk (I:)" in "My Computer".
• Now, whether you have reached this stage by connecting via a cable to a PC, or you have a file manager on your Android device, the process is the same. You want to navigate to "\Android\data\uk.co.fordartworks.SourcesGL.lite\files\definitions". Here you will see all of your "old" definitions. Select all or as many as you want to keep, do "copy" in your file manager or PC and paste them into "\Android\data\uk.co.fordartworks.SourcesGL.pro\files\definitions" .
• If you have attached to a PC via a cable, then unmount or disconnect your Android device storage - this will generally be done in a very similar way to how you mounted/connected it a couple of steps earlier. (Consult you device's documentation if you are unsure.) Disconnect the USB cable.
• All that remains is to get these definitions back into the working storage area for Apps. Start up SourcesPro. Go to the Options menu, click "More...", then click "Load Defs into App". There may be a delay of up to a couple of minutes if you have copied a large number of old definitions. When this operation finishes, look in your "Load..." menu and you should see all of your definitions transferred and available for use in SourcesPro.

• Wallpaper. Sources is ideal for creating still wallpaper images - just follow your usual procedure for setting an image from the gallery as wallpaper. Rather more excitingly, as of v1.3, SourcesPro will allow the creation and editing of definitions for the new, free! live wallpaper app SourcesWP. My main interest in Sources is in the creation of high quality still images, but playing with live wallpapers is a lot of fun.