java - Rendering Large Rectangular Tiled Images with an OpenGL QuadTree -


i designing , developing bespoke imagery viewer exceptionally large image files (sometimes in gigapixels). fortunately these provided 256x256 tiles in staged resolution layers, passed across opengl when required.

the tiles managed via quadtree seems strong solution "almost power-of-two" images. given image extremely wide aspect ratio (e.g. 1 gigapixel x 50,000) model starts falter large amounts of null tiles. there ever limited number of tile's on display @ time.

i using java 7 lwjgl provide opengl context.
quadtree solution fit problem, or there better alternatives managing data?

edit: edited title make more sense.

the quad tree enforces split along both coordinate axes. problems has wide aspect 1 of axes oversplit.

you have 2 solutions:

  • use bsp. similar concept instead of spliting both coordinate ranges pick 1 , split 2. can split along large range more on smaller one.
  • use grid of quadtrees @ top level. way split space rough squares make better use of bits. suggested @andreas in comments.

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