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[cmbruns]

In version 0.7.0 we have a wait cursor in the image pane, and a message in the status bar. But it would be nice to have a little progress spinner somewhere too.

[cmbruns]

• [x] Display "wait" cursor while image is loading.
• [x] Post "loading..." message in status bar.
• [x] Put progress bar in status bar during load.
• [ ] Display a placeholder texture as soon as the oriented image size is known.
  • [x] Put all glsl files into a sub package
  • [ ] Use a vertex buffer with omp coordinates, to support future tiled images
  • [ ] Use a uniform buffer object maybe
  • [ ] Put (image?) view state and shader reference into image_data
• [ ] Display a thumbnail image, if available, when the image is above a certain size.
• [x] Post and "loaded" or "load failed" messages in status bar.