metaforce/Runtime/Graphics/CPVSVisSet.cpp

#include "Runtime/Graphics/CPVSVisSet.hpp"

#include "Runtime/Graphics/CPVSVisOctree.hpp"

namespace metaforce {

void CPVSVisSet::Reset(EPVSVisSetState state) {
  x0_state = state;
  x4_numBits = 0;
  x8_numLights = 0;
  // xc_ = false;
  x10_ptr = nullptr;
}

EPVSVisSetState CPVSVisSet::GetVisible(u32 idx) const {
  if (x0_state != EPVSVisSetState::NodeFound)
    return x0_state;

  u32 numFeatures = x4_numBits - x8_numLights;
  if (idx < numFeatures) {
    /* This is a feature lookup */
    if (!(x10_ptr[idx / 8] & (1 << (idx & 0x7))))
      return EPVSVisSetState::EndOfTree;
    return EPVSVisSetState::OutOfBounds;
  }

  /* This is a light lookup */
  u32 lightTest = idx - numFeatures + idx;
  const u8* ptr = &x10_ptr[lightTest / 8];
  lightTest &= 0x7;
  if (lightTest != 0x7)
    return EPVSVisSetState((ptr[0] & (0x3 << lightTest)) >> lightTest);
  return EPVSVisSetState((ptr[0] >> 7) | ((ptr[1] & 0x1) << 1));
}

void CPVSVisSet::SetFromMemory(u32 numBits, u32 numLights, const u8* leafPtr) {
  x0_state = EPVSVisSetState::NodeFound;
  x4_numBits = numBits;
  x8_numLights = numLights;
  x10_ptr = leafPtr;
}

void CPVSVisSet::SetTestPoint(const CPVSVisOctree& octree, const zeus::CVector3f& point) {
  if (!octree.GetBounds().pointInside(point)) {
    Reset(EPVSVisSetState::OutOfBounds);
    return;
  }

  const u8* octCur = octree.GetOctreeData();
  octree.ResetSearch();
  s32 nextNodeRel;
  u8 curNode;
  while ((nextNodeRel = octree.IterateSearch((curNode = *octCur++), point)) != -1) {
    if (nextNodeRel) {
      /* Skip node data */
      if (!(curNode & 0x60)) {
        octCur += hecl::SBig(reinterpret_cast<const u16*>(octCur)[nextNodeRel - 1]);
      } else if (curNode & 0x20) {
        octCur += *(octCur + nextNodeRel - 1);
      } else {
        const u8* tmp = octCur + (nextNodeRel - 1) * 3;
        octCur += (tmp[0] << 16) + (tmp[1] << 8) + tmp[2];
      }
    }

    /* Skip children data */
    if (!(curNode & 0x60)) {
      octCur += (octree.GetNumChildren(curNode) - 1) * 2;
    } else if (curNode & 0x20) {
      octCur += octree.GetNumChildren(curNode) - 1;
    } else {
      octCur += (octree.GetNumChildren(curNode) - 1) * 3;
    }
  }

  /* Handle leaf type */
  switch (curNode & 0x18) {
  case 0x18:
    SetFromMemory(octree.GetNumObjects(), octree.GetNumLights(), octCur);
    break;
  case 0x10:
    Reset(EPVSVisSetState::EndOfTree);
    break;
  case 0x08:
  default:
    Reset(EPVSVisSetState::OutOfBounds);
    break;
  }
}

} // namespace metaforce