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#include "rail.h"
#include "game/network/link.h"
#include <GL/glew.h>
#include <array>
#include <cache.h>
#include <cassert>
#include <gfx/gl/shader.h>
#include <gfx/models/texture.h>
#include <gfx/models/vertex.hpp>
#include <glm/gtx/transform.hpp>
#include <initializer_list>
#include <maths.h>
#include <stdexcept>
#include <type_traits>
#include <utility>
constexpr auto RAIL_CROSSSECTION_VERTICES {5U};
constexpr glm::vec3 RAIL_HEIGHT {0, .25F, 0};
RailLinks::RailLinks() : texture {Texture::cachedTexture.get("rails.jpg")} { }
void RailLinks::tick(TickDuration) { }
void
RailLinks::joinLinks(const LinkPtr & l) const
{
for (const auto & ol : links.objects) {
if (l != ol) {
for (const auto oe : {0, 1}) {
for (const auto te : {0, 1}) {
if (l->ends[te].first == ol->ends[oe].first) {
l->nexts[te].emplace_back(ol, oe);
ol->nexts[oe].emplace_back(l, te);
}
}
}
}
}
}
std::shared_ptr<RailLink>
RailLinks::addLinksBetween(glm::vec3 start, glm::vec3 end)
{
auto node1ins = nodes.insert(std::make_shared<Node>(start));
auto node2ins = nodes.insert(std::make_shared<Node>(end));
if (node1ins.second && node2ins.second) {
// Both nodes are new, direct link, easy
return addLink<RailLinkStraight>(start, end);
}
if (node1ins.second && !node2ins.second) {
// node1 is new, node2 exists, but we build from existing outwards
std::swap(node1ins, node2ins);
std::swap(start, end);
}
// Find start link/end - opposite entry dir to existing link; so pi +...
float dir = pi + [this](const auto & n) {
for (const auto & l : links.objects) {
for (const auto & e : l->ends) {
if (e.first == n) {
return e.second;
}
}
}
throw std::runtime_error("Node exists but couldn't find it");
}(*node1ins.first);
const glm::vec2 flatStart {start.x, start.z}, flatEnd {end.x, end.z};
// if (node2ins.second) { // Unimplemented second arc/stright required
const auto diff {end - start};
const auto vy {vector_yaw(diff)};
const auto n2ed {(vy * 2) - dir - pi};
const auto centre {find_arc_centre(flatStart, dir, flatEnd, n2ed)};
if (centre.second) { // right hand arc
std::swap(start, end);
}
return addLink<RailLinkCurve>(start, end, centre.first);
}
void
RailLinks::render(const Shader & shader) const
{
shader.setModel(glm::identity<glm::mat4>());
texture->Bind();
links.apply(&RailLink::render, shader);
}
void
RailLink::defaultMesh()
{
for (auto n = RAIL_CROSSSECTION_VERTICES; n < vertices.size(); n += 1) {
indices.push_back(n - RAIL_CROSSSECTION_VERTICES);
indices.push_back(n);
}
assert(vertices.capacity() == vertices.size());
assert(indices.capacity() == indices.size());
meshes.create<Mesh>(vertices, indices, GL_TRIANGLE_STRIP);
}
void
RailLink::render(const Shader &) const
{
meshes.apply(&Mesh::Draw);
}
constexpr const std::array<std::pair<glm::vec3, float>, RAIL_CROSSSECTION_VERTICES> railCrossSection {{
// ___________
// _/ \_
// left to right
{{-1.9F, 0.F, 0.F}, 0.F},
{{-.608F, RAIL_HEIGHT.y, 0.F}, 0.34F},
{{0, RAIL_HEIGHT.y * .7F, 0.F}, 0.5F},
{{.608F, RAIL_HEIGHT.y, 0.F}, 0.66F},
{{1.9F, 0.F, 0.F}, 1.F},
}};
constexpr auto sleepers {5.F}; // There are 5 repetitions of sleepers in the texture
inline auto
round_sleepers(const float v)
{
return round_frac(v, sleepers);
}
RailLinkStraight::RailLinkStraight(const NodePtr & a, const NodePtr & b) : RailLinkStraight(a, b, b->pos - a->pos) { }
RailLinkStraight::RailLinkStraight(NodePtr a, NodePtr b, const glm::vec3 & diff) :
RailLink({std::move(a), vector_yaw(diff)}, {std::move(b), vector_yaw(-diff)}, glm::length(diff))
{
vertices.reserve(2 * railCrossSection.size());
indices.reserve(2 * railCrossSection.size());
const auto len = round_sleepers(length / 2.F);
const auto e {flat_orientation(diff)};
for (int ei = 0; ei < 2; ei++) {
const auto trans {glm::translate(ends[ei].first->pos) * e};
for (const auto & rcs : railCrossSection) {
const glm::vec3 m {(trans * glm::vec4 {rcs.first, 1})};
vertices.emplace_back(m, glm::vec2 {rcs.second, ei ? len : 0.F}, up);
}
}
defaultMesh();
}
Transform
RailLinkStraight::positionAt(float dist, unsigned char start) const
{
const auto es {std::make_pair(ends[start].first.get(), ends[1 - start].first.get())};
const auto diff {es.second->pos - es.first->pos};
const auto dir {glm::normalize(diff)};
return Transform {es.first->pos + RAIL_HEIGHT + dir * dist, {-vector_pitch(dir), vector_yaw(dir), 0}};
}
RailLinkCurve::RailLinkCurve(const NodePtr & a, const NodePtr & b, glm::vec2 c) :
RailLinkCurve(a, b, {c.x, a->pos.y, c.y}, {!c, a->pos, b->pos})
{
}
RailLinkCurve::RailLinkCurve(const NodePtr & a, const NodePtr & b, glm::vec3 c, const Arc arc) :
RailLink({a, normalize(arc.first + half_pi)}, {b, normalize(arc.second - half_pi)},
(glm::length(a->pos - c)) * arc_length(arc)),
centreBase(c), radius {glm::length(ends[0].first->pos - centreBase)}, arc {arc}
{
const auto & e0p {ends[0].first->pos};
const auto & e1p {ends[1].first->pos};
const auto slength = round_sleepers(length / 2.F);
const auto segs = std::round(5.F * slength / std::pow(radius, 0.7F));
const auto step {glm::vec3 {-arc_length(arc), e0p.y - e1p.y, slength} / segs};
const auto trans {glm::translate(centreBase)};
int segCount = segs;
vertices.reserve((segCount + 1) * railCrossSection.size());
indices.reserve(segCount * 2 * railCrossSection.size());
for (glm::vec3 swing = {arc.second, e1p.y - centreBase.y, 0.F}; segCount >= 0; swing += step, --segCount) {
const auto t {trans * glm::rotate(swing.x - half_pi, up) * glm::translate(glm::vec3 {radius, swing.y, 0.F})};
for (const auto & rcs : railCrossSection) {
const glm::vec3 m {(t * glm::vec4 {rcs.first, 1})};
vertices.emplace_back(m, glm::vec2 {rcs.second, swing.z}, up);
}
}
defaultMesh();
}
Transform
RailLinkCurve::positionAt(float dist, unsigned char start) const
{
static constexpr std::array<float, 2> dirOffset {half_pi, -half_pi};
const auto frac {dist / length};
const auto es {std::make_pair(ends[start].first.get(), ends[1 - start].first.get())};
const auto as {std::make_pair(arc[start], arc[1 - start])};
const auto ang {as.first + ((as.second - as.first) * frac)};
const auto angArc {ang - half_pi};
const auto relPos {glm::vec3 {std::cos(angArc), 0, -std::sin(angArc)} * radius};
const auto relClimb {RAIL_HEIGHT
+ glm::vec3 {0, -centreBase.y + es.first->pos.y + ((es.second->pos.y - es.first->pos.y) * frac), 0}};
const auto pitch {vector_pitch({0, (es.first->pos.y - es.second->pos.y) / length, 0})};
return Transform {relPos + relClimb + centreBase, {pitch, normalize(ang + dirOffset[start]), 0}};
}
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