et

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Offline claude

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« Reply #30 on: September 26, 2018, 07:18:14 PM »
Here are some test images. My program is written in Haskell, with a working title of BossaNova (from Burning Ship Series Approximation).  It doesn't do glitch detection or correction yet.

the kf images should have the locations embedded.

As you can see there are some issues, the "a" image is noticeably (un)skewed - but this even occurs with the series iterations forced to 0, so maybe something is broken in the series evaluation or initialization? EDIT fixed the skew, was an off-by-one in the perturbation iterations (it used the new reference instead of the old reference)

Also the b image seems to have a circular core instead of a miniship, rendering larger now but it's taking a long time, as my code is super inefficient - these render in a few seconds in KF, minutes with BossaNova...
« Last Edit: September 26, 2018, 08:51:06 PM by claude, Reason: fixed the skew »

Offline claude

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« Reply #31 on: July 02, 2019, 04:39:41 PM »
et-gtk (implemented in Haskell) is reasonably usable for exploration now:
- formula compiler with functional formula entry text widget
- mouse and keyboard controls for navigation (zoom, translate, rotate - no manual skew controls yet)
- analytic distance estimation, smooth iteration count, argmin_p |z_p| available for colouring (more options planned)
- perturbation rendering for deep zooming
- Newton zooming to mini-ship (works well) or embedded Julia set (experimental)
- auto skew with 3 methods (mini-local, Jacobian d/dc, Jacobian d/dc with d/dz too) (not aesthetically useful for all formulas, needs more research)
- sRGB gamma-correct supersampling via downscaled mipmaps (up to 8192x8192, depending on what OpenGL supports on your GPU - et-cli can go (I think..) up to 65536x65536)
- image save/load with formula and location metadata including one-keypress save to ~/Pictures/et/

next major TODO items:
- implement runtime colouring controls other than DE weight, perhaps via OpenGL fragment shader
- compute more layers for colouring algorithms (eg: z at min|z|, z at escape, ...)
- formula randomization button in the GUI
- image RGB histogram overlay, (mutlti)fractal dimension estimates, etc

also working on a bot for auto-zooming to interesting locations, more on that later

Offline claude

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« Reply #32 on: July 02, 2019, 04:51:47 PM »
Code: [Select]
Formula
 z:=(|y|+i|x|)^p+c
 z:=((-|y|)+i|x|)^p+c

p=4
q=2
d=1.0
e=0.0
a=-1.044585021345374
b=-0.15889347512983232
r=9.5367431640625e-7
t=(1.0,0.0,0.0,1.0)
n=4096

de=0.25

Offline claude

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« Reply #33 on: July 02, 2019, 05:06:34 PM »
Code: [Select]
Formula
 z:=(|y|+i(-|x|))^p+c
 z:=((-x)+iy)^p+c
 z:=((-y)+i(-|x|))^p+c
 z:=(|x|+i(-|y|))^p+c

p=3
q=2
d=1.0
e=0.0
a=-0.776170257999831300000004
b=0.1152689215106033
r=1.1920928955078125e-7
t=(1.0,0.0,0.0,1.0)
n=4096

de=0.25