Large style->height parameter causes blank rendering

[cmdcolin]

Unknown reasons but it seems to come up totally blank sometimes with larger style->height

[cmdcolin]

For the 1000 genomes case, it may be running into the maximum size limit of a canvas.

http://stackoverflow.com/questions/6081483/maximum-size-of-a-canvas-element

This suggests maximum size of a canvas is around the max size of a signed short (2^15-1=32,767)

For example, for 1000 genomes, style.height=13 works but style.height=14 doesn't. With 2504 samples in the 1000 genomes, this means that 14 breaks it but 13 does not

2504*13
[1] 32552
2504*14
[1] 35056