ericw-tools/qbsp/csg4.cc

386 lines
10 KiB
C++

/*
Copyright (C) 1996-1997 Id Software, Inc.
Copyright (C) 1997 Greg Lewis
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
See file, 'COPYING', for details.
*/
// csg4.c
#include <qbsp/brush.hh>
#include <qbsp/csg4.hh>
#include <qbsp/map.hh>
#include <qbsp/solidbsp.hh>
#include <qbsp/qbsp.hh>
#include <atomic>
#include <mutex>
#include "tbb/parallel_for.h"
/*
NOTES
-----
Brushes that touch still need to be split at the cut point to make a tjunction
*/
// acquire this for anything that can't run in parallel during CSGFaces
std::mutex csgfaces_lock;
/*
==================
MakeSkipTexinfo
==================
*/
int MakeSkipTexinfo()
{
// FindMiptex, FindTexinfo not threadsafe
std::unique_lock<std::mutex> lck{csgfaces_lock};
mtexinfo_t mt{};
mt.miptex = FindMiptex("skip", true);
mt.flags = {};
mt.flags.is_skip = true;
return FindTexinfo(mt);
}
/*
==================
NewFaceFromFace
Duplicates the non point information of a face, used by SplitFace and
MergeFace.
==================
*/
face_t *NewFaceFromFace(const face_t *in)
{
face_t *newf = new face_t{};
newf->planenum = in->planenum;
newf->texinfo = in->texinfo;
newf->planeside = in->planeside;
newf->contents = in->contents;
newf->lmshift = in->lmshift;
newf->src_entity = in->src_entity;
newf->origin = in->origin;
newf->radius = in->radius;
return newf;
}
face_t* CopyFace(const face_t* in)
{
face_t *temp = NewFaceFromFace(in);
temp->w = in->w;
return temp;
}
void UpdateFaceSphere(face_t *in)
{
in->origin = in->w.center();
in->radius = 0;
for (size_t i = 0; i < in->w.size(); i++) {
in->radius = max(in->radius, qv::distance2(in->w[i], in->origin));
}
in->radius = sqrt(in->radius);
}
/*
==================
SplitFace
Frees in. Returns {front, back}
==================
*/
std::tuple<face_t *, face_t *> SplitFace(face_t *in, const qplane3d &split)
{
vec_t *dists = (vec_t *)alloca(sizeof(vec_t) * (in->w.size() + 1));
side_t *sides = (side_t *)alloca(sizeof(side_t) * (in->w.size() + 1));
std::array<size_t, SIDE_TOTAL> counts{};
vec_t dot;
size_t i, j;
face_t *newf, *new2;
qvec3d mid;
if (in->w.size() < 0)
Error("Attempting to split freed face");
/* Fast test */
dot = split.distance_to(in->origin);
if (dot > in->radius) {
counts[SIDE_FRONT] = 1;
counts[SIDE_BACK] = 0;
} else if (dot < -in->radius) {
counts[SIDE_FRONT] = 0;
counts[SIDE_BACK] = 1;
} else {
counts = in->w.calc_sides(split, dists, sides, ON_EPSILON);
}
// Plane doesn't split this face after all
if (!counts[SIDE_FRONT]) {
return {nullptr, in};
}
if (!counts[SIDE_BACK]) {
return {in, nullptr};
}
newf = NewFaceFromFace(in);
new2 = NewFaceFromFace(in);
// distribute the points and generate splits
for (i = 0; i < in->w.size(); i++) {
// Note: Possible for numpoints on newf or new2 to exceed MAXEDGES if
// in->w.numpoints == MAXEDGES and it is a really devious split.
const qvec3d &p1 = in->w[i];
if (sides[i] == SIDE_ON) {
newf->w.push_back(p1);
new2->w.push_back(p1);
continue;
}
if (sides[i] == SIDE_FRONT) {
new2->w.push_back(p1);
} else {
newf->w.push_back(p1);
}
if (sides[i + 1] == SIDE_ON || sides[i + 1] == sides[i])
continue;
// generate a split point
const qvec3d &p2 = in->w[(i + 1) % in->w.size()];
dot = dists[i] / (dists[i] - dists[i + 1]);
for (j = 0; j < 3; j++) { // avoid round off error when possible
if (split.normal[j] == 1)
mid[j] = split.dist;
else if (split.normal[j] == -1)
mid[j] = -split.dist;
else
mid[j] = p1[j] + dot * (p2[j] - p1[j]);
}
newf->w.push_back(mid);
new2->w.push_back(mid);
}
if (newf->w.size() > MAXEDGES || new2->w.size() > MAXEDGES)
FError("Internal error: numpoints > MAXEDGES");
/* free the original face now that it is represented by the fragments */
delete in;
// {front, back}
return {new2, newf};
}
face_t *MirrorFace(const face_t *face)
{
face_t *newface = NewFaceFromFace(face);
newface->w = face->w.flip();
newface->planeside = face->planeside ^ 1;
newface->contents.swap();
newface->lmshift.swap();
return newface;
}
static void FreeFaces(std::list<face_t *> &facelist)
{
for (face_t *face : facelist) {
delete face;
}
facelist.clear();
}
//==========================================================================
static std::vector<std::unique_ptr<brush_t>> SingleBrush(std::unique_ptr<brush_t> a)
{
std::vector<std::unique_ptr<brush_t>> res;
res.push_back(std::move(a));
return res;
}
/*
==================
SubtractBrush
Returns the fragments from a - b
==================
*/
static std::vector<std::unique_ptr<brush_t>> SubtractBrush(std::unique_ptr<brush_t> a, const brush_t& b)
{
// first, check if `a` is fully in front of _any_ of b's planes
for (const auto &side : b.faces) {
// is `a` fully in front of `side`?
bool fully_infront = true;
// fixme-brushbsp: factor this out somewhere
for (const auto &a_face : a->faces) {
for (const auto &a_point : a_face.w) {
if (Face_Plane(&side).distance_to(a_point) < 0) {
fully_infront = false;
break;
}
}
if (!fully_infront) {
break;
}
}
if (fully_infront) {
// `a` is fully in front of this side of b, so they don't actually intersect
return SingleBrush(std::move(a));
}
}
std::vector<std::unique_ptr<brush_t>> frontlist;
std::vector<std::unique_ptr<brush_t>> unclassified = SingleBrush(std::move(a));
for (const auto &side : b.faces) {
std::vector<std::unique_ptr<brush_t>> new_unclassified;
for (auto &fragment : unclassified) {
// destructively processing `unclassified` here
auto [front, back] = SplitBrush(std::move(fragment), Face_Plane(&side));
if (front) {
frontlist.push_back(std::move(front));
}
if (back) {
new_unclassified.push_back(std::move(back));
}
}
unclassified = std::move(new_unclassified);
}
return frontlist;
}
/*
==================
BrushGE
Returns a >= b as far as brush clipping
==================
*/
bool BrushGE(const brush_t& a, const brush_t& b)
{
// same contents clip each other
if (a.contents == b.contents && a.contents.clips_same_type()) {
// map file order
return a.file_order > b.file_order;
}
// only chop if at least one of the two contents is
// opaque (solid, sky, or detail)
if (!(a.contents.chops(options.target_game) || b.contents.chops(options.target_game))) {
return false;
}
int32_t a_pri = a.contents.priority(options.target_game);
int32_t b_pri = b.contents.priority(options.target_game);
if (a_pri == b_pri) {
// map file order
return a.file_order > b.file_order;
}
return a_pri >= b_pri;
}
/*
==================
ChopBrushes
Clips off any overlapping portions of brushes
==================
*/
std::vector<std::unique_ptr<brush_t>> ChopBrushes(const std::vector<std::unique_ptr<brush_t>>& input)
{
logging::print(logging::flag::PROGRESS, "---- {} ----\n", __func__);
// each inner vector corresponds to a brush in `input`
// (set up this way for thread safety)
std::vector<std::vector<std::unique_ptr<brush_t>>> brush_fragments;
brush_fragments.resize(input.size());
/*
* For each brush, clip away the parts that are inside other brushes.
* Solid brushes override non-solid brushes.
* brush => the brush to be clipped
* clipbrush => the brush we are clipping against
*
* The output of this is a face list for each brush called "outside"
*/
tbb::parallel_for(static_cast<size_t>(0), input.size(), [&](const size_t i) {
const auto& brush = input[i];
// the fragments `brush` is chopped into
std::vector<std::unique_ptr<brush_t>> brush_result = SingleBrush(
// start with a copy of brush
std::make_unique<brush_t>(*brush)
);
for (auto &clipbrush : input) {
if (brush == clipbrush) {
continue;
}
if (brush->bounds.disjoint(clipbrush->bounds)) {
continue;
}
if (BrushGE(*clipbrush, *brush)) {
std::vector<std::unique_ptr<brush_t>> new_result;
// clipbrush is stronger.
// rebuild existing fragments in brush_result, cliping them to clipbrush
for (auto &current_fragment : brush_result) {
for (auto &new_fragment : SubtractBrush(std::move(current_fragment), *clipbrush)) {
new_result.push_back(std::move(new_fragment));
}
}
brush_result = std::move(new_result);
}
}
// save the result
brush_fragments[i] = std::move(brush_result);
});
// Non parallel part:
std::vector<std::unique_ptr<brush_t>> result;
for (auto &fragment_list : brush_fragments) {
for (auto &fragment : fragment_list) {
result.push_back(std::move(fragment));
}
}
logging::print(logging::flag::STAT, " {:8} brushes\n", input.size());
logging::print(logging::flag::STAT, " {:8} chopped brushes\n", result.size());
return result;
}