LOVJ

A LÖVE2D VJing framework

LOVJ aims to be a LÖVE framework to create a live-coding, interactive VJing environment mainly targeted at live music performances. It revolves around the concept of video patches: these can be loaded, sequenced, and mixed in several ways.

It allows interaction with the patches through:

• code editing (with livecoding hot-reload features)
• common controls (mouse / keyboard / touch)
• external controls (OSC)

Moreover, it supports advanced functionalities such as:

• GLSL shaders support (for advanced rendering techniques, such as ray-marching).
• Spout Send/Receive functions (allowing streaming to/from external apps, feedback loops, etc.).
• Savestates (save/recall patches internal status quickly).
• OSC network server via UDP.

Setup

• LÖVE version 11.4+
• Add LOVE2D bin folder to your PATH variable
• Download/clone this repository.
• From this repo main folder (containing the main.lua script), run:

love .

Usage

General

• F1 ... F12 to switch between patches.
• CTRL + Return toggle fullscreen.
• CTRL + S toggle shader on/off
• CTRL + U upscale
• S cycle through effects

Visual effects adjustments

You should use them in combination with the UP or DOWN arrow keys to change the effect intensity, after selecting the corresponding effect with the S key.

• W for warp effect
• K kaleidoscope effect
• G blur effect

Porting GLSL shaders

You can port GLSL shaders to LOVJ by creating a new patch in postProcess and readapt the shader code.

Keep in mind that in order to modify the shader parameters, you need to pass everything in cfg/cfg_shaders.lua

Assuming that your shader is called "porting", this is how a shader should look like:

-- lib/shaders/postProcess/19_porting.glsl
vec4 effect(vec4 color, Image tex, vec2 texture_coords, vec2 screen_coords) {
    -- your shader code here
}

Passing time to shader

One common use case, is pass the time parameter to a shader:

-- cfg/cfg_shaders.lua
if string.find(shader.name, "porting") then
    shader.object:send("_time", cfg_timers.globalTimer.T)
end

Passing a parameter to shader

Another useful common use case is to pass a parameter to the shader that can be controlled by the user.

In this specific case, your GLSL shader should look like

external float _whateverParameter;

vec4 effect(vec4 color, Image tex, vec2 texture_coords, vec2 screen_coords) {
    ...
}

And in the cfg_shaders.lua file, you should add:

-- cfg/cfg_shaders.lua
-- ...
-- porting
if kp.isDown("m") then
    if kp.isDown("up") then s:set("_whateverParameter", (s:get("_whateverParameter") + 0.1)) end
    if kp.isDown("down") then s:set("_whateverParameter", (s:get("_whateverParameter") - 0.1)) end
end

Feel free to adapt the parameter name and the value to your needs, this is just an example that binds the parameter to the M key and allows to change it with the UP and DOWN arrow keys.

Then, in order to use the shader, you need to cycle through the effects with the S key, until you reach the desired effect.

Issues

LOVJ is still in a work-in-progress state. Development is messy and several features are kind of broken. It can be played with, but don't expect the software to be working reliably in its current state. Check Issue tracker for more info.

Running the demos

• Open cfg/cfg_patches.lua.
• Edit the defaultPatch or the patches list.
• Run LOVJ.
• Select the chosen demo from patches with the [F1 ... F12] keys.

Credits

• lick original LICK implementation for live-coding features (MIT license).
• json.lua v.0.1.2 Json library (MIT license).
• losc v.1.0.1 Lua OSC library (MIT license).
• Spout Spout library (BSD-2 license).

MIDI to OSC

A simple tool to relay MIDI messages to OSC messages based on some configuration can be found here.