Rendering Engine: Big images aware

[jburel]

Add method

• retrieve viewport. For initial step we can use ROI, might new to add that to rendering def
• retrieve zooming level
• render region

There are several methods that may be added to the RenderingEngine to accommodate BigImages:
RenderRegionAsPacketInt(RenderDef, Region)

Render the region specified by the Region Parameter as a Packed Int.

RenderTileAsPacketInt(RenderDef, row, col)

Render the tile in the bigImage specified by row and col.

RenderRegionAsTileasPacketInt(RenderDef, Region)

Render the tiles that span the region as Packet Int.

Region is defined as

  x : int
  y : int
  width : int
  height : int