// rzm_pin_detected.hlsl
// RZMenu: Pins the closest hovered object ID detected during the frame,
//         copies extended hit metadata, and resets the per-frame accumulator.
//
// Expected bindings:
//   cs-u0 = ResourceRZMDetectID,         RWBuffer<float4> (frame accumulator)
//   cs-u1 = ResourceRZMPinnedDetectID,   RWBuffer<float>  (legacy pinned R32_FLOAT)
//   cs-u2 = ResourceRZMPinnedDetectInfo, RWBuffer<float4> (pinned extended info)
//
// Accumulator/pinned info layout:
//   [0] legacy ABI, do not reorder:
//       x = best hit ID (-1 on miss)
//       y = best depth
//       z = firstIndex of winning range
//       w = hit triangle count
//   [1] xyz = hit point on object, world space; w = object mode
//   [2] x = firstIndex; y = absolute indexBase; z = local triangle; w = face ID
//   [3] x/y/z = absolute vertex indices; w = nearest vertex slot
//   [4] xyz = barycentric hit weights; w = inside-triangle flag
//   [5] xyz = geometric face normal, world space; w = screen winding sign
//   [6] xyz = nearest vertex position, world space; w = screen distance squared
//   [7] x = layout version; y = object index; z = object count; w = nearest vertex index
//
// After running:
//   ResourceRZMPinnedDetectID[0]   = best.x (used by INI store -> $Detected)
//   ResourceRZMPinnedDetectInfo[*] = copied extended info, or miss/reset payload
//   ResourceRZMDetectID[*]         = reset for next frame

#define RZM_DETECT_SLOTS 8u

RWBuffer<float4> gAccumulated : register(u0);
RWBuffer<float>  gPinnedID    : register(u1);
RWBuffer<float4> gPinnedInfo  : register(u2);

static const float kHugeDepth = 3.402823e+38f;
static const float4 kResetSlot0 = float4(-1.0f, kHugeDepth, 0.0f, 0.0f);
static const float4 kResetSlotN = float4(0.0f, 0.0f, 0.0f, 0.0f);

[numthreads(1, 1, 1)]
void main(uint3 dispatchThreadID : SV_DispatchThreadID)
{
    float4 best    = gAccumulated[0];
    bool   invalid = best.x < 0.0f || best.y > 1e30f;

    gPinnedID[0] = invalid ? -1.0f : best.x;

    [unroll]
    for (uint slot = 0u; slot < RZM_DETECT_SLOTS; slot++)
    {
        float4 value = invalid ? (slot == 0u ? kResetSlot0 : kResetSlotN) : gAccumulated[slot];
        gPinnedInfo[slot] = value;
        gAccumulated[slot] = slot == 0u ? kResetSlot0 : kResetSlotN;
    }
}
