Rendering Command Implementation Notes

The output of the state sorting stage is a large list of the individual commands that are to be rendered using OpenGL or OpenAL. In this document we describe the various sets of commands and the order that they can be expected in, so that implementations can be coded to work with it. Each of these commands are represented by constants defined in the org.j3d.aviatrix3d.pipeline.RenderOps interface.

Single Layer

Corresponds scene graph that has a single layer and single viewport with no layers in the viewport, and no transparent objects, lights, fog etc.

1. START_VIEWPORT
2. START_LAYER
3. START_RENDER
4. START_STATE
5. RENDER_GEOMETRY
6. STOP_STATE
7. STOP_RENDER
8. continue for as many objects are are in the scene
9. STOP_LAYER
10. STOP_VIEWPORT

Multiple Layers

Corresponds scene graph that has a multiple layers each with a single viewport with no layers in the viewport, and no transparent objects, lights, fog etc.

1. START_VIEWPORT
2. START_LAYER
3. START_RENDER
4. START_STATE
5. RENDER_GEOMETRY
6. STOP_STATE
7. STOP_RENDER
8. continue for as many objects are are in the scene
9. STOP_LAYER
10. STOP_VIEWPORT
11. START_VIEWPORT
12. START_LAYER
13. START_RENDER
14. START_STATE
15. RENDER_GEOMETRY
16. STOP_STATE
17. STOP_RENDER
18. continue for as many objects are are in the scene
19. STOP_LAYER
20. STOP_VIEWPORT
21. ... for however many layers

Multiple Viewports in a single layer

Corresponds scene graph that has a single layer containing multiple viewports with no layers in the viewports, and no transparent objects, lights, fog etc.

1. START_VIEWPORT
2. START_LAYER
3. START_RENDER
4. START_STATE
5. RENDER_GEOMETRY
6. STOP_STATE
7. STOP_RENDER
8. continue for as many objects are are in the scene
9. STOP_LAYER
10. STOP_VIEWPORT
11. START_VIEWPORT
12. START_LAYER
13. START_RENDER
14. START_STATE
15. RENDER_GEOMETRY
16. STOP_STATE
17. STOP_RENDER
18. continue for as many objects are are in the scene
19. STOP_LAYER
20. STOP_VIEWPORT

This pattern repeats per layer, so if you have multple layers with multiple viewports, you'll see the same pattern repeated for each successive layer.

Multipass Rendering

Corresponds scene graph that has a single layer and single viewport with no layers in the viewport. The viewport contains a multipass scene with 2 rendering passes (though it can be generalised to n passes, with no transparent objects, lights, fog etc.

1. START_VIEWPORT
2. START_LAYER
3. START_MULTIPASS
4. START_MULTIPASS_STATE (for up to 4 different buffers)
5. START_MULTIPASS_PASS
6. START_RENDER
7. START_STATE
8. RENDER_GEOMETRY
9. STOP_STATE
10. STOP_RENDER
11. continue for as many objects are are in the scene
12. STOP_MULTIPASS_PASS
13. STOP_MULTIPASS_STATE (for up to 4 different buffers)
14. CHANGE_MULTIPASS_STATE (for up to 4 different buffers)
15. START_MULTIPASS_STATE (for up to 4 different buffers)
16. START_MULTIPASS_PASS
17. START_RENDER
18. START_STATE
19. RENDER_GEOMETRY
20. STOP_STATE
21. STOP_RENDER
22. continue for as many objects are are in the scene
23. STOP_MULTIPASS_PASS
24. STOP_MULTIPASS_STATE (for up to 4 different buffers)
25. STOP_LAYER
26. STOP_VIEWPORT

Combined Multipass and Single Pass Rendering

Corresponds scene graph that has a two layers: The first containing a single pass render and the second containing a multipass render. The second layer contains a multipass scene with 2 rendering passes (though it can be generalised to n passes, with no transparent objects, lights, fog etc.

1. START_VIEWPORT
2. START_LAYER
3. START_RENDER
4. START_STATE
5. RENDER_GEOMETRY
6. STOP_STATE
7. STOP_RENDER
8. continue for as many objects are are in the scene
9. STOP_LAYER
10. START_LAYER
11. STOP_VIEWPORT
12. START_VIEWPORT
13. START_MULTIPASS
14. START_MULTIPASS_STATE (for up to 4 different buffers)
15. START_MULTIPASS_PASS
16. START_RENDER
17. START_STATE
18. RENDER_GEOMETRY
19. STOP_STATE
20. STOP_RENDER
21. continue for as many objects are are in the scene
22. STOP_MULTIPASS_PASS
23. STOP_MULTIPASS_STATE (for up to 4 different buffers)
24. CHANGE_MULTIPASS_STATE (for up to 4 different buffers)
25. START_MULTIPASS_STATE (for up to 4 different buffers)
26. START_MULTIPASS_PASS
27. START_RENDER
28. START_STATE
29. RENDER_GEOMETRY
30. STOP_STATE
31. STOP_RENDER
32. continue for as many objects are are in the scene
33. STOP_MULTIPASS_PASS
34. STOP_MULTIPASS_STATE (for up to 4 different buffers)
35. STOP_LAYER
36. STOP_VIEWPORT