Sorry Buddhi, I was waiting for someone with more experience than myself to say something about the user formulas before I pitched in.
I've had a brief play with the user formulas, but I haven't gotten all that far with them, so I'd like to wait to see what others have to say about them, but the system does seem pretty powerful.
Just out of curiosity though, did you have to write a whole compiler extension (tokeniser, lexer, parser, code gen, etc.) from scratch, or was it part of a library or something? It's something I might like to do myself at some point, but I've no idea what to search for on Google on the subject.
As for the crashes, it does seem noticeably more stable, and the error reports help.
I've managed to identify one particular crash on my system. When trying to render any kind of Mandelbox, it crashes if I enable AO (as opposed to SSAO), but only when the camera is outside of the box. It seems to be quite happy doing proper grown-up AO from inside.
That crash gives me this error:
ERROR: ComamndQueue::finish() - Kernel (-36)
There's another crash, but so far, I haven't been able to identify exactly what it doesn't like. Just certain frames of an animation I'm doing.
ERROR: ComamndQueue::enqueueReadBuffer() (-36)
For that one.
Oh, here we go. This frame is the culprit. I don't know if it's any help, but here's the settings:
Mandelbulber 1.1899999999999999;
image_width 2560;
image_height 1440;
view_point_x -4.4299999999999997;
view_point_y -4.6600000000000001;
view_point_z -5;
angle_alfa -13.467000000000001;
angle_beta 0;
zoom 3.703703703703704e-009;
perspective 0.75;
formula 8;
quality 2;
ambient_occlusion 1.5;
background_color_1_G 0;
background_color_1_B 0;
background_color_2_R 0;
background_color_2_G 0;
background_color_2_B 0;
background_color_1_G 0;
background_color_1_B 0;
coloring_speed 300;
coloring_palette_offset 57.799999999999997;
main_light_intensity 1.5;
main_light_alfa 0.52359877559829882;
main_light_beta 0.52359877559829882;
start_frame 434;
end_frame 1800;
fish_eye 1;
mandelbox_color_X 0;
mandelbox_color_Y 0;
mandelbox_color_Z 0;
view_distance_max 52.398030754403003;
Other than that, great work Buddhi, and thank you very much for putting the power in the hands of the people (formula wise).
I'm intrigued to see what other people come up with, and looking forward hopefully to learning a thing or two about fractal formulas.
Edit: I've just noticed that the above crash seems to happen as the raymarcher crosses the centre line of the image, which is actually looking straight down a long line of fractal repetitions that are getting particularly detailed in that 'spinning off to infinity' way that fractals do. The frames either side of it seem perfectly happy. Don't know if that's any help.