Here is a WIP project, to check with the future spherical billboard.
big_flare.png should always stay above and in front of logo.png.
Thank you, Patrice. I hope it will stay there -- some day.
Also, as long as we use a quad, it would be nice to handle rectangular mesh without any square-fit stretching (just like the wallpaper background).
You will have to exert yourself, my friend, to see it happen.
Now I have a request. I do not understand why ObjReader's camera behaves so weird with billboards. In fact, it refuses to support any type of billboarding and moreover, it fights against it going plain wild and crazy.
Apart from the three functions from your 3D chart bubble sprite sources that you have already published here, I need two more pieces of
3D chart camera code:
1. I need your exact 3D chart render routine -- the analog to gl_DrawScene() in the ObjReader sources. All of it without any abridgments or ommissions. I must know 100% exactly in what state OpenGL is when it draws the bubbles; if it's still in a LoadIdentity(), MODELVIEW and/or PROJECTION state, before/in the process of/after the drawing of wallpaper and other geometry, if that other geometry is already translated/rotated somehow or not yet and if yes then using pure OpenGL or rather your obscure GDImage magic, etc. etc. etc.
2. I need an abstract from your 3D chart message handling routine -- the analog to ProcessMouseInput() in the ObjReader sources in what concerns the handling of WM_LBUTTONDOWN/WM_RBUTTONDOWN/WM_MBUTTONDOWN/WM_MOUSEWHEEL and the entire WM_MOUSEMOVE. In fact, all parts that modify or affect in any way the rotation angles and/or translation distances, including possible transformations in what may be the analogs to ObjReader's Mobj_normalize(), Mobj_scale() and similar.
3. I need you absolute willingness to co-operate and advise me openly and thoroughly on all other matters that may arise when I study the sources as per items 1 and 2 above. I really wouldn't like having to make blind guesses or reverse engineer your other products when writing the ObjReader code for you.
C4D_project.png shows you how the meshes have been put horizontally in front of the cycle, with the star flare being put slightly above the tron logo.
No! Billboards -- cylindrical or spherical -- should
never ever be put on the ground! Their
centers must always exist in the model at their
exact XZ positions and Y heights where you intend to be seeing them at view time!
( If someone's camera differs from everybody else's cameras in just one pixel, degree, radian, or degree of a radian -- just as little as your FPS counter differs from mine -- then it's a lost case and the project is f*cked up beyond all repair. That someone ends up in hell with a totally custom camera that can't utilize a single bit of the entire knowledge base from the net. 
)
