isle-portable/LEGO1/realtime/realtime.cpp

#include "realtime.h"

// OFFSET: LEGO1 0x100a5b40
void CalcLocalTransform(const MxVector3 &p_posVec, const MxVector3 &p_dirVec,
                        const MxVector3 &p_upVec, MxMatrix &p_outMatrix)
{
  MxFloat x_axis[3], y_axis[3], z_axis[3];

  // This is an unrolled version of the "NORMVEC3" macro,
  // used here to apply a silly hack to get a 100% match
  {
    const MxFloat dirVec1Operation = (p_dirVec)[1] * (p_dirVec)[1];
    MxDouble len = sqrt(((p_dirVec)[0] * (p_dirVec)[0] + dirVec1Operation + (p_dirVec)[2] * (p_dirVec)[2]));
    ((z_axis)[0] = (p_dirVec)[0] / (len), (z_axis)[1] = (p_dirVec)[1] / (len), (z_axis)[2] = (p_dirVec)[2] / (len));
  }

  NORMVEC3(y_axis, p_upVec)

  VXV3(x_axis, y_axis, z_axis);

  // Exact same thing as pointed out by the above comment
  {
    const MxFloat axis2Operation = (x_axis)[2] * (x_axis)[2];
    MxDouble len = sqrt(((x_axis)[0] * (x_axis)[0] + axis2Operation + (x_axis)[1] * (x_axis)[1]));
    ((x_axis)[0] = (x_axis)[0] / (len), (x_axis)[1] = (x_axis)[1] / (len), (x_axis)[2] = (x_axis)[2] / (len));
  }

  VXV3(y_axis, z_axis, x_axis);

  // Again, the same thing
  {
    const MxFloat axis2Operation = (y_axis)[2] * (y_axis)[2];
    MxDouble len = sqrt(((y_axis)[0] * (y_axis)[0] + axis2Operation + (y_axis)[1] * (y_axis)[1]));
    ((y_axis)[0] = (y_axis)[0] / (len), (y_axis)[1] = (y_axis)[1] / (len), (y_axis)[2] = (y_axis)[2] / (len));
  }

  SET4from3(&p_outMatrix[0], x_axis,    0);
  SET4from3(&p_outMatrix[4], y_axis,    0);
  SET4from3(&p_outMatrix[8], z_axis,    0);
  SET4from3(&p_outMatrix[12], p_posVec, 1);
}