gzdoom/src/nodebuild_classify_sse2.cpp

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2016-03-01 15:47:10 +00:00
#ifndef DISABLE_SSE
#include "doomtype.h"
#include "nodebuild.h"
#define FAR_ENOUGH 17179869184.f // 4<<32
// You may notice that this function is identical to ClassifyLine2.
// The reason it is SSE2 is because this file is explicitly compiled
// with SSE2 math enabled, but the other files are not.
extern "C" int ClassifyLineSSE2 (node_t &node, const FSimpleVert *v1, const FSimpleVert *v2, int sidev[2])
{
double d_x1 = double(node.x);
double d_y1 = double(node.y);
double d_dx = double(node.dx);
double d_dy = double(node.dy);
double d_xv1 = double(v1->x);
double d_xv2 = double(v2->x);
double d_yv1 = double(v1->y);
double d_yv2 = double(v2->y);
double s_num1 = (d_y1 - d_yv1) * d_dx - (d_x1 - d_xv1) * d_dy;
double s_num2 = (d_y1 - d_yv2) * d_dx - (d_x1 - d_xv2) * d_dy;
int nears = 0;
if (s_num1 <= -FAR_ENOUGH)
{
if (s_num2 <= -FAR_ENOUGH)
{
sidev[0] = sidev[1] = 1;
return 1;
}
if (s_num2 >= FAR_ENOUGH)
{
sidev[0] = 1;
sidev[1] = -1;
return -1;
}
nears = 1;
}
else if (s_num1 >= FAR_ENOUGH)
{
if (s_num2 >= FAR_ENOUGH)
{
sidev[0] = sidev[1] = -1;
return 0;
}
if (s_num2 <= -FAR_ENOUGH)
{
sidev[0] = -1;
sidev[1] = 1;
return -1;
}
nears = 1;
}
else
{
nears = 2 | int(fabs(s_num2) < FAR_ENOUGH);
}
if (nears)
{
double l = 1.f / (d_dx*d_dx + d_dy*d_dy);
if (nears & 2)
{
double dist = s_num1 * s_num1 * l;
if (dist < SIDE_EPSILON*SIDE_EPSILON)
{
sidev[0] = 0;
}
else
{
sidev[0] = s_num1 > 0.0 ? -1 : 1;
}
}
else
{
sidev[0] = s_num1 > 0.0 ? -1 : 1;
}
if (nears & 1)
{
double dist = s_num2 * s_num2 * l;
if (dist < SIDE_EPSILON*SIDE_EPSILON)
{
sidev[1] = 0;
}
else
{
sidev[1] = s_num2 > 0.0 ? -1 : 1;
}
}
else
{
sidev[1] = s_num2 > 0.0 ? -1 : 1;
}
}
else
{
sidev[0] = s_num1 > 0.0 ? -1 : 1;
sidev[1] = s_num2 > 0.0 ? -1 : 1;
}
if ((sidev[0] | sidev[1]) == 0)
{ // seg is coplanar with the splitter, so use its orientation to determine
// which child it ends up in. If it faces the same direction as the splitter,
// it goes in front. Otherwise, it goes in back.
if (node.dx != 0)
{
if ((node.dx > 0 && v2->x > v1->x) || (node.dx < 0 && v2->x < v1->x))
{
return 0;
}
else
{
return 1;
}
}
else
{
if ((node.dy > 0 && v2->y > v1->y) || (node.dy < 0 && v2->y < v1->y))
{
return 0;
}
else
{
return 1;
}
}
}
else if (sidev[0] <= 0 && sidev[1] <= 0)
{
return 0;
}
else if (sidev[0] >= 0 && sidev[1] >= 0)
{
return 1;
}
return -1;
}
#endif