#version 300 es
layout(location = 0) in vec3 aPos;
layout(location = 1) in vec3 aNormal;
layout(location = 2) in vec4 aInstRot;
layout(location = 3) in vec3 aInstPos;
layout(location = 4) in vec3 aInstScale;
layout(location = 5) in vec4 aInstColor;
layout(location = 6) in vec4 aInstParams;   // x = emissive, y = receiveShadow, z = fresnel, w = bands
layout(location = 7) in vec4 aInstFx;       // x = flow strength, y = noise scale, z = vertex warp (world units), w = ring band (world units)
#include "_graphics_uniforms.glsl"
out highp vec3 vNormal;
out highp vec3 vWorldPos;
out vec3 vObjPos;   // unit-primitive position — stable domain for the band pattern
out vec4 vColor;
out float vEmissive;
out float vReceiveShadow;
out vec2 vMaterial;   // x = fresnel, y = bands
out vec2 vFlow;       // x = strength, y = noise scale
vec3 quatRotate(vec4 q, vec3 v) {
    return v + 2.0 * cross(q.xyz, cross(q.xyz, v) + q.w * v);
}
void main() {
    vec3 pos = aPos;
    // absolute ring band: pull a ring's inner verts (radius < 1) out to a constant world-unit width,
    // so a scaling shockwave front stays slim instead of thickening with its radius
    if (aInstFx.w > 0.0) {
        float r = length(pos.xy);
        if (r > 0.001 && r < 0.99) {
            float innerObj = max(1.0 - aInstFx.w / max(aInstScale.x, 0.001), 0.0);
            pos.xy = (pos.xy / r) * innerObj;
        }
    }
    vec3 world = quatRotate(aInstRot, pos * aInstScale) + aInstPos;
    // inverse-transpose of a diagonal scale is 1/scale — exact for axis-aligned box normals
    vNormal = quatRotate(aInstRot, normalize(aNormal / aInstScale));
    // vertex warp: traveling waves along the surface + a fast high-frequency shiver — field energy,
    // not a drifting blob
    if (aInstFx.z > 0.0) {
        highp float t = u_timeParams.y;
        highp vec2 p = world.xy * aInstFx.y;
        float n = sin(p.x * 2.3 + p.y * 1.9 - t * 3.1) * 0.55
                + sin(p.x * -1.4 + p.y * 2.6 + t * 2.3) * 0.35
                + sin((p.x + p.y) * 3.7 - t * 7.0) * 0.25;
        world += vNormal * (n * aInstFx.z);
    }
    gl_Position = u_viewProjection * vec4(world, 1.0);
    vWorldPos = world;
    vObjPos = aPos;
    vColor = aInstColor;
    vEmissive = aInstParams.x;
    vReceiveShadow = aInstParams.y;
    vMaterial = aInstParams.zw;
    vFlow = aInstFx.xy;
}