PhosphorISF shaders on a Mac, for free
ISF is the shader format VDMX made popular: a GLSL fragment shader with a JSON header that describes its controls. Phosphor runs them natively, as generators and as effects, with 325 of the 327 shaders in the public ISF collection importing today.
Where to put them
Phosphor scans the same folders VDMX uses: /Library/Graphics/ISF and ~/Library/Graphics/ISF, plus ~/Documents/VDMX Media/ISF and its own folder (Help → Open ISF Shader Folder). Drop .fs files (and their .vs if they have one) there and they appear in the Sources and Effects browsers within seconds, converted in the background; the first use compiles on a worker thread so the show never hitches.
What works
Single-pass and multi-pass shaders, persistent (feedback) buffers, imported pictures, up to 60 controls, event buttons, colour and point inputs, and audio / audioFFT inputs fed by a live waveform and spectrum from whatever the audio panel listens to, including the music Phosphor itself plays. MadMapper materials import too when MadMapper is installed (its MadNoise and MadSDF includes have clean-room equivalents).
Audio-reactive shaders
Set the Audio panel to a microphone, an input, or Clip sound (the clips Phosphor plays) and every shader with an audio or audioFFT input gets the live signal; Radial Spectrogram, Audio Waveform Shape and the rest of the collection move with the music. Any shader control can also be driven by LFOs, audio bands or the beat with a right-click → Modulate.
Write your own
The Shader Editor panel compiles as you type, with a live preview and errors on the line. Phosphor's own format is WGSL with a short header for controls; ISF files you write by hand work the same way, and the importer tells you exactly what it could not convert.
Questions
Which ISF shaders don't work?
Two of the 327 in the collection: ones that have no JSON header at all. Shaders whose vertex stage moves geometry are shown without that movement.
Can I use my VDMX shader folder as it is?
Yes. Phosphor reads /Library/Graphics/ISF and ~/Library/Graphics/ISF directly; nothing to copy.
Do ISF shaders work in the browser version?
Yes, the same converter runs there. Audio inputs follow the browser's audio source.
Is Phosphor free?
Yes, free and open source (GPL) for Mac, and in Chrome or Edge.
More: free VJ software for Mac · coming from MadMapper · coming from Resolume · coming from VDMX.