MapLibreParticleLab/shaders/retained_underlay_composite.vertex.glsl

layout (location = 0) in vec2 a_pos;
out vec2 v_uv;

void main() {
    gl_Position = vec4(a_pos.x * 2.0 - 1.0, 1.0 - a_pos.y * 2.0, 0.0, 1.0);
    v_uv = vec2(a_pos.x, 1.0 - a_pos.y);
}