tech - visual programming 

Added rotation and skew to FragM's Camera2D code. Doing it only in the shaders is not possible because the mouse interactions don't match up with the image.

Hacked on some C++ code, to make a Logarithmic mode for sliders in Fragmentarium, most useful for the Camera2D Zoom shader uniform variable.

Demo video: mathr.co.uk/misc/2019-08-15_lo (25MB, 45secs)

mildly strobing video 

```
fract(0.5 * dwell + time / 3.0) < 0.5
? vec3(1.0, 0.0, 0.0)
: vec3(1.0);
```

Where dwell (aka ) is computed 4x per pixel for image-space distance estimation (because using dFdx and dFdy on computed data is too low-resolution and fraught with peril in the event of incoherent control flow, works fine for the input smooth coordinates to know where to offset the 4x dwell computations).

For some reason I always seem to end up with that look a bit like insects

Actually it turns out building a better parser for uniform/GUI mapping that respects is a because so many things are by the GPU driver and it's tricky to get at them from outside shader source, and it's trickier to get things from inside shader source to outside.

My current code works to an extent which is good enough for me, as long as I don't poke it.

rendered a with version of

the trick is to replace (in your camera frag vertex block) all uses of the `Zoom` uniform by `Zoom*pow(2.0, ZoomFactor)` and add a Linear easing curve to new `ZoomFactor` uniform.

keep ZoomFactor at 0 while navigating for sanity

this toot brought to you by "Qt's InExpo easing curve is a bit rubbish" code.qt.io/cgit/qt/qtbase.git/

claude boosted

Yikes, I really need to cut down even more on my meat consumption. 1 kg beef has an equivalent carbon opportunity cost as flying a return trip across the Atlantic!

monbiot.com/2019/08/13/spectre

#climate_crisis
#farming
#transportation

Got dynamic switching between float and double working (based on derivatives of pixel coordinates). But I don't know if it's actually computing both and switching afterwards - there isn't much noticeable speed increase at shallow zooms. GPUs are weird.

But there are some bugs in FragM that mean my desired workflow is not yet attainable: the code that parses the shader for annotations about uniforms to build a GUI with is a bit dumb and doesn't respect preprocessor , which I was hoping to use to fallback to float when double is unavailable.

Similar deal with and , even commenting it out doesn't help if the is the first thing on a line...

claude boosted

uk politics, brexit, petition 

claude boosted

a reminder that the perseids meteor shower has started and will reach it's highest activity around the 12th of august 🌠🌠

uk politics, brexit, petition 

I ported some of the formulas I use in to , for faster rendering. Because of legacy baggage in the existing code of I started work on a new framework for 2D fragment within FragM.

Similar in spirit to (my physically inspired raytracer for FragM), only with the added complication of wanting to support double precision ( 4) where available, while still working to some extent (without so deep zooms) on single precision float (OpenGL 3) if that is all the can do. Only single precision is implemented so far.

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