OctBounds.cpp

#include "Components/Core/SceneComponent.h"
#include "Components/Core/TransformComponent.h"
#include "Systems/Core/TransformSystem.h"
#include "Context.h"
 
#include "Systems/OctSystem.h"
#include "OctBounds.h"
 
void Cogs::Core::Volumetric::OctBounds::getBounds(Context * context, Cogs::Geometry::BoundingBox & bounds)
{
  for (const auto & octComp : octSystem->pool) {
    const auto & octtreeData = octSystem->getData(&octComp);
 
    if (octtreeData.nodes.empty()) return;
 
    const auto * sceneComp = octComp.getComponent<SceneComponent>();
    if (sceneComp->visible == false) return;
 
    const auto * transComp = octComp.getComponent<TransformComponent>();
    auto & worldMatrix = context->transformSystem->getLocalToWorld(transComp);
 
    const auto & apex = octtreeData.nodes.back();
 
    const auto s = 1 << apex.ix4.w;
    for (unsigned i = 0; i < 8; i++) {
      auto r = glm::vec3(octtreeData.alignMinToZeroShift.x + s*int(apex.ix4.x + (i & 1)),
                         octtreeData.alignMinToZeroShift.y + s*int(apex.ix4.y + ((i >> 1) & 1)),
                         octtreeData.alignMinToZeroShift.z + s*int(apex.ix4.z + ((i >> 2) & 1)));
 
      auto q = octComp.blockExtent * r + octComp.blockShift;
      auto p = worldMatrix * glm::vec4(q, 1.f);
      auto l = (1.f / p.w)*glm::vec3(p.x, p.y, p.z);
 
      bounds += l;
    }
  }
}