int TestLine_r( int node, vec3_t start, vec3_t stop ){
tnode_t *tnode;
float front, back;
vec3_t mid;
float frac;
int side;
int r;
if ( node & ( 1 << 31 ) ) {
return node & ~( 1 << 31 ); // leaf node
}
tnode = &tnodes[node];
switch ( tnode->type )
{
case PLANE_X:
front = start[0] - tnode->dist;
back = stop[0] - tnode->dist;
break;
case PLANE_Y:
front = start[1] - tnode->dist;
back = stop[1] - tnode->dist;
break;
case PLANE_Z:
front = start[2] - tnode->dist;
back = stop[2] - tnode->dist;
break;
default:
front = ( start[0] * tnode->normal[0] + start[1] * tnode->normal[1] + start[2] * tnode->normal[2] ) - tnode->dist;
back = ( stop[0] * tnode->normal[0] + stop[1] * tnode->normal[1] + stop[2] * tnode->normal[2] ) - tnode->dist;
break;
}
if ( front >= -ON_EPSILON && back >= -ON_EPSILON ) {
return TestLine_r( tnode->children[0], start, stop );
}
if ( front < ON_EPSILON && back < ON_EPSILON ) {
return TestLine_r( tnode->children[1], start, stop );
}
side = front < 0;
frac = front / ( front - back );
mid[0] = start[0] + ( stop[0] - start[0] ) * frac;
mid[1] = start[1] + ( stop[1] - start[1] ) * frac;
mid[2] = start[2] + ( stop[2] - start[2] ) * frac;
r = TestLine_r( tnode->children[side], start, mid );
if ( r ) {
return r;
}
return TestLine_r( tnode->children[!side], mid, stop );
}
/*
==============
TestPatchToFace
Sets vis bits for all patches in the face
==============
*/
void TestPatchToFace (unsigned patchnum, int facenum, int head, unsigned bitpos)
{
patch_t *patch = &patches[patchnum];
patch_t *patch2 = face_patches[facenum];
// if emitter is behind that face plane, skip all patches
if ( patch2 && DotProduct(patch->origin, patch2->normal) > PatchPlaneDist(patch2)+1.01 )
{
// we need to do a real test
for ( ; patch2 ; patch2 = patch2->next)
{
unsigned m = patch2 - patches;
// check vis between patch and patch2
// if bit has not already been set
// && v2 is not behind light plane
// && v2 is visible from v1
if ( m > patchnum
&& DotProduct (patch2->origin, patch->normal) > PatchPlaneDist(patch)+1.01
&& TestLine_r (head, patch->origin, patch2->origin) == CONTENTS_EMPTY )
{
// patchnum can see patch m
int bitset = bitpos+m;
vismatrix[ bitset>>3 ] |= 1 << (bitset&7);
}
}
}
int TestLine_color (int node, vec3_t start, vec3_t stop, vec3_t occluded)
{
occluded[0] = occluded[1] = occluded[2] = 1.0;
if (doing_texcheck)
return TestLine_r_texcheck (node, 0, start, stop, start, stop, occluded);
else
return TestLine_r (node, start, stop);
}
int TestLine (vec3_t start, vec3_t stop)
{
vec3_t occluded;
occluded[0] = occluded[1] = occluded[2] = 1.0;
if (doing_texcheck)
return TestLine_r_texcheck (0, 0, start, stop, start, stop, occluded);
else
return TestLine_r (0, start, stop);
}
//without texture checking
int TestLine_r (int node, vec3_t set_start, vec3_t stop)
{
tnode_t *tnode;
float front, back;
vec3_t mid, _start;
vec_t *start;
float frac;
int side;
int r;
start = set_start;
re_test:
r = 0;
if (node & (1<<31))
{
if ((r = node & ~(1<<31)) != CONTENTS_WINDOW)
{
return r;
}
return 0;
}
tnode = &tnodes[node];
switch (tnode->type)
{
case PLANE_X:
front = start[0] - tnode->dist;
back = stop[0] - tnode->dist;
break;
case PLANE_Y:
front = start[1] - tnode->dist;
back = stop[1] - tnode->dist;
break;
case PLANE_Z:
front = start[2] - tnode->dist;
back = stop[2] - tnode->dist;
break;
default:
front = (start[0]*tnode->normal[0] + start[1]*tnode->normal[1] + start[2]*tnode->normal[2]) - tnode->dist;
back = (stop[0]*tnode->normal[0] + stop[1]*tnode->normal[1] + stop[2]*tnode->normal[2]) - tnode->dist;
break;
}
if (front >= -ON_EPSILON && back >= -ON_EPSILON)
{
node = tnode->children[0];
goto re_test;
}
if (front < ON_EPSILON && back < ON_EPSILON)
{
node = tnode->children[1];
goto re_test;
}
side = front < 0;
frac = front / (front-back);
mid[0] = start[0] + (stop[0] - start[0])*frac;
mid[1] = start[1] + (stop[1] - start[1])*frac;
mid[2] = start[2] + (stop[2] - start[2])*frac;
if ((r = TestLine_r (tnode->children[side], start, mid)))
return r;
node = tnode->children[!side];
start = _start;
start[0] = mid[0];
start[1] = mid[1];
start[2] = mid[2];
goto re_test;
}
int TestLine (vec3_t start, vec3_t stop)
{
return TestLine_r (0, start, stop);
}
