rodecomp/Source/Contents/World/WorldOcclusion.cpp

#include "Contents/Ground/GroundGeometry.h"
#include "Contents/Models/ModelActor.h"
#include "Contents/World/WorldOcclusion.h"
#include "Contents/World/WorldRayQuery.h"
#include "Contents/World/WorldSpatialTree.h"
#include "Render/Projection/RenderProjection.h"

#include "Utility/Math/ScalarConversion.h"
#include <cstring>

// INLINED
void MarkWorldOcclusionRay(const float* ray, float actorLimit, float groundLimit, WorldSpatialTree& root, GroundGeometry& ground, bool markGround) {
  float actorRay[7];
  std::memcpy(actorRay, ray, 6 * sizeof(float));
  actorRay[6] = actorLimit;
  WorldRayQuery query;
  query.Collect(ray, &root);

  for (WorldSpatialTree* node : query.nodes) {
    for (C3dActor* model : node->objects) {
      model->MarkOccluded(actorRay);
    }
  }

  if (markGround) {
    for (WorldSpatialTree* node : query.nodes) {
      int row = node->groundCells[1];

      while (row <= node->groundCells[3]) {
        int column = node->groundCells[0];

        while (column <= node->groundCells[2]) {
          ground.MarkRay(ray, column, row, groundLimit);
          ++column;
        }

        ++row;
      }
    }
  }
}

// FUNCTION: fn_21286
void MarkScreenWorldOcclusion(
  const RenderProjection& projection, int screenX, int screenY, float rendererScale, const float* origin, const float* cameraMatrix, float playerHeight,
  float cameraHeight, WorldSpatialTree& root, GroundGeometry& ground, bool markGround
) {
  const float shifted = static_cast<float>(screenY) - rendererScale * 23.0f;
  const int y = TruncateToInt(shifted);
  float ray[6]{};
  projection.Ray(screenX, y, origin, cameraMatrix, ray);
  const float limit = (playerHeight + cameraHeight) - 16.0f;
  MarkWorldOcclusionRay(ray, limit, limit, root, ground, markGround);
}