I have a series of control pages that time out to a sort of Indigo-based screensaver for iPad mini wall-based controllers. The way it works is this:
- I have a small (2 pixels by 2 pixels), blank PNG that is invisible on a page. This is called screendim+.png and also saved as screendim+false.png
- I have a large number of photos called screendim+n.png where n is a reference number between 1 and X. Each of these is 2060 x 1545 pixels)
- I have a variable called ScreenDim which is either false or a random number between 1 and X. It defaults to false after a set period of time
- I insert the screendim+ image on a control page to reflect the variable state of ScreenDim, and with a client action to switch ScreenDim to false when the image is pressed.
- Every five minutes, the variable changes to a different number (and hence image).
This works pretty well (would be even better if I got the photos exactly the right size, but they are very close). The default is that an image shows. If I tap the image, I reveal the control beneath, and after fifteen minutes or so, the screensaver starts again.
But there's a problem (of course because otherwise I wouldn't be posting). For an iPad page displaying in Indigo Touch, the PNG needs to be located right in the middle of the control page - Indigo Touch centres the image on the page. But if I then view that control page in Safari (either on the iPad or on a computer), the photo images display down and to the right, only covering a quarter of the screen - Safari seems to put the top left hand corner of the image in the centre of the control page, rather than the centre of the image.
Is this a bug? Am I doing something wrong?