correctly generate and render edges

This commit is contained in:
2019-09-14 21:42:12 -04:00
parent 2e4e84ab80
commit a3573acca4
7 changed files with 156 additions and 59 deletions

View File

@@ -13,11 +13,14 @@ using namespace std;
class CosetsWindow : public Window {
GLint program;
GLuint tri;
GLuint points_vao, edges_vao;
GLuint verts;
GLuint verts_buf;
std::vector<glm::vec4> verts_data;
GLuint edges_buf;
std::vector<int> edge_data;
public:
void init() override {
auto vs = build_shader_file(
@@ -32,21 +35,34 @@ public:
program = build_program("main", vs, fs);
verts_data = vertices<3>(
schlafli<3>({5, 3}),
{10, 1, 1});
const Mults &mults = schlafli<4>({3, 4, 3});
verts_data = vertices<4>(mults, {10, 1, 1, 1});
edge_data = edges<4>(mults);
glGenBuffers(1, &verts);
glBindBuffer(GL_ARRAY_BUFFER, verts);
glGenBuffers(1, &verts_buf);
glBindBuffer(GL_ARRAY_BUFFER, verts_buf);
glBufferData(GL_ARRAY_BUFFER, sizeof(glm::vec4) * verts_data.size(), &verts_data[0], GL_STATIC_DRAW);
glGenBuffers(1, &edges_buf);
glBindBuffer(GL_ARRAY_BUFFER, edges_buf);
glBufferData(GL_ARRAY_BUFFER, sizeof(int) * edge_data.size(), &edge_data[0], GL_STATIC_DRAW);
glGenVertexArrays(1, &tri);
glBindVertexArray(tri);
glBindBuffer(GL_ARRAY_BUFFER, verts);
glGenVertexArrays(1, &points_vao);
glBindVertexArray(points_vao);
glBindBuffer(GL_ARRAY_BUFFER, verts_buf);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 4, GL_FLOAT, false, 0, nullptr);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glGenVertexArrays(1, &edges_vao);
glBindVertexArray(edges_vao);
glBindBuffer(GL_ARRAY_BUFFER, verts_buf);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 4, GL_FLOAT, false, 0, nullptr);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, edges_buf);
glBindVertexArray(0);
}
void render() override {
@@ -66,26 +82,30 @@ public:
const glm::mat4 proj = glm::ortho(-ar * sc, ar * sc, -sc, sc, -10.f, 10.f);
const glm::mat4 view = glm::rotate(id, angle, ax_1) * glm::rotate(id, angle, ax_2);
const glm::mat4 mat = proj * view;
glUseProgram(program);
glUniformMatrix4fv(1, 1, false, glm::value_ptr(mat));
glUniformMatrix4fv(1, 1, false, glm::value_ptr(proj));
glUniformMatrix4fv(2, 1, false, glm::value_ptr(view));
glEnable(GL_DEPTH_TEST);
glEnable(GL_POINT_SMOOTH);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glPointSize(10.f);
glBindVertexArray(tri);
glBindVertexArray(points_vao);
glUniform4f(0, 1, 1, 1, 1);
glDrawArrays(GL_POINTS, 0, verts_data.size());
glBindVertexArray(edges_vao);
glUniform4f(0, 1, 1, 0, 1);
glDrawElements(GL_LINES, edge_data.size(), GL_UNSIGNED_INT, 0);
swapbuffers();
}
void deinit() override {
glDeleteProgram(program);
glDeleteVertexArrays(1, &tri);
glDeleteVertexArrays(1, &points_vao);
}
};

View File

@@ -1,20 +1,14 @@
#include "util/mesh.hpp"
int main(int argc, char *argv[]) {
const auto &mults = schlafli<4>({4, 3, 3});
const std::vector<glm::vec4> &vs = vertices<4>(mults, {10, 1, 1, 1});
const int N = 3;
const Mults &mults = schlafli<N>({4, 3});
const std::vector<glm::vec4> &vs = vertices<N>(mults, {10, 1, 1});
for (const auto &v:vs) {
std::cout << glm::to_string(v) << std::endl;
}
std::cout << "# verts: " << vs.size() << std::endl;
// Table *table = solve({}, mults);
// std::cout << table->size() << std::endl;
//
// for (const auto &rel : mults.relations()) {
// for (const auto &e : rel) {
// std::cout << e << " ";
// }
// std::cout << std::endl;
// }
}
const auto es = edges<N>(mults);
return 0;
}

View File

@@ -1,6 +1,7 @@
#version 440 core
uniform mat4 proj;
uniform mat4 view;
in vec4 pos;
out vec4 v;
@@ -9,7 +10,10 @@ out vec4 screen;
void main(){
v = pos;
vec4 vert = view * pos;
/* stereographic projection */
vec4 vert = vec4(pos.xyz / (1 - pos.w), 1);
vert = vec4(vert.xyw / (1 - vert.z), 1);
screen = gl_Position = proj * vert;
}

View File

@@ -1,6 +1,7 @@
#pragma once
#include <iostream>
#include <utility>
#include <vector>
#include <iomanip>
#include <algorithm>
@@ -8,7 +9,6 @@
#include <map>
#include <tuple>
template<int N>
struct Mults {
std::map<std::tuple<int, int>, int> mults{};
@@ -40,11 +40,11 @@ struct Mults {
return res;
}
[[nodiscard]] std::vector<std::vector<int>> relations() const {
[[nodiscard]] std::vector<std::vector<int>> relations(std::vector<int> gens) const {
std::vector<std::vector<int>> res{};
for (int a = 0; a < N; ++a) {
for (int b = a; b < N; ++b) {
res.push_back(relation(a, b));
for (int a = 0; a < gens.size(); ++a) {
for (int b = a; b < gens.size(); ++b) {
res.push_back(relation(gens[a], gens[b]));
}
}
return res;
@@ -52,8 +52,8 @@ struct Mults {
};
template<int N>
Mults<N> schlafli(const int (&symbol)[N - 1]) {
Mults<N> mults{};
Mults schlafli(const int (&symbol)[N - 1]) {
Mults mults{};
for (int i = 0; i < N; ++i) {
mults.set(i, i + 1, symbol[i]);
}
@@ -61,23 +61,31 @@ Mults<N> schlafli(const int (&symbol)[N - 1]) {
}
struct Table {
int N;
const std::vector<int> gens;
std::vector<std::vector<int>> fwd{};
std::vector<std::vector<int>> rev{};
explicit Table(int N) {
this->N = N;
explicit Table(const std::vector<int> gens) : gens(gens) {
add_row();
}
[[nodiscard]] int gen_index(int gen) const {
for (unsigned i = 0; i < gens.size(); ++i)
if (gens[i] == gen)
return i;
throw std::logic_error("Referencing nonexistant generator");
}
void add_row() {
int N = gens.size();
fwd.emplace_back(N, -1);
rev.emplace_back(N, -1);
}
int add_coset() {
for (int from = 0; from < (int) size(); ++from) {
for (int gen = 0; gen < N; ++gen) {
for (int gen : gens) {
if (get(from, gen) < 0) {
int to = (int) size();
add_row();
@@ -94,16 +102,19 @@ struct Table {
}
void set(int from, int gen, int to) {
fwd[from][gen] = to;
rev[to][gen] = from;
int i = gen_index(gen);
fwd[from][i] = to;
rev[to][i] = from;
}
[[nodiscard]] int get(int from, int gen) const {
return fwd[from][gen];
int i = gen_index(gen);
return fwd[from][i];
}
[[nodiscard]] int rget(int gen, int to) const {
return rev[to][gen];
int i = gen_index(gen);
return rev[to][i];
}
std::vector<std::vector<int>> words() {
@@ -117,7 +128,7 @@ struct Table {
continue;
}
for (int gen = 0; gen < (int) N; ++gen) {
for (int gen : gens) {
int to = get(from, gen);
if (vecs[to] != nullptr) {
continue;
@@ -137,6 +148,31 @@ struct Table {
return res;
}
[[nodiscard]] int apply(int e, const std::vector<int> &word) const {
for (const auto &gen : word) {
e = get(e, gen);
}
return e;
}
[[nodiscard]] int apply(const std::vector<int> &word) const {
return apply(0, word);
}
[[nodiscard]] std::vector<int> apply_each(int e, const std::vector<std::vector<int>> &words) const {
std::vector<int> res{};
for (const auto &word:words) {
res.push_back(apply(e, word));
}
return res;
}
[[nodiscard]] std::vector<int> apply_each(const std::vector<std::vector<int>> &words) const {
return apply_each(0, words);
}
};
struct Row {
@@ -192,10 +228,8 @@ std::ostream &operator<<(std::ostream &out, const Row &row) {
return out;
}
template<int N>
Table *solve(const std::vector<int> &subgens, const Mults<N> &mults) {
const auto rels = mults.relations();
int gens = N;
Table *solve(const std::vector<int> &gens, const std::vector<int> &subgens, const Mults &mults) {
const auto rels = mults.relations(gens);
auto *table = new Table(gens);
for (int gen : subgens)
@@ -231,6 +265,15 @@ Table *solve(const std::vector<int> &subgens, const Mults<N> &mults) {
return table;
}
template<int N>
Table *solve(const std::vector<int> &subgens, const Mults &mults) {
std::vector<int> gens{};
for (int i = 0; i < N; ++i) {
gens.push_back(i);
}
return solve(gens, subgens, mults);
}
std::ostream &operator<<(std::ostream &out, const Table &table) {
int k = ceil(log10(table.size()));
@@ -238,10 +281,10 @@ std::ostream &operator<<(std::ostream &out, const Table &table) {
for (unsigned j = 0; j < table.size(); ++j) {
auto arr = table.fwd[j];
out << " " << std::setw(k) << j << " [";
for (int i = 0; i < table.N; ++i) {
for (int i = 0; i < (int) table.gens.size(); ++i) {
out << arr[i];
if (i < table.N - 1)
if (i < table.gens.size() - 1)
out << " ";
}

View File

@@ -23,8 +23,8 @@ glm::vec4 identity(const std::vector<glm::vec4> &normals, const float(&coords)[N
template<int N>
std::vector<glm::vec4>
vertices(const Mults<N> &mults, const float (&coords)[N]) {
Table *table = solve({}, mults);
vertices(const Mults &mults, const float (&coords)[N]) {
Table *table = solve<N>({}, mults);
const std::vector<glm::vec4> normals = mirror<N>(mults);
glm::vec4 ident = identity(normals, coords);
@@ -42,9 +42,25 @@ vertices(const Mults<N> &mults, const float (&coords)[N]) {
}
template<int N>
std::vector<unsigned> lines(const Mults<N> &mults) {
// Table *table = solve(N, {}, coxeter_rels(mults));
std::vector<int> edges(const Mults &mults) {
std::vector<int> res{};
return {};
Table *verts = solve<N>({}, mults);
int K = 1;
for (const auto &subgens : combinations(N, K)) {
Table *edge = solve(subgens, {}, mults);
std::vector<int> primitive = verts->apply_each(edge->words());
Table *cosets = solve<N>(subgens, mults);
for (const auto &coset : cosets->words()) {
for (const auto &e : primitive) {
res.push_back(verts->apply(e, coset));
}
}
}
return res;
}

View File

@@ -11,7 +11,7 @@
#include "coxeter.hpp"
template<int N>
std::vector<glm::vec4> mirror(const Mults<N> &mults) {
std::vector<glm::vec4> mirror(const Mults &mults) {
static_assert(1 <= N and N <= 4, "Vector size is unsupported");
std::vector<glm::vec4> mirrors{};

View File

@@ -57,3 +57,23 @@ std::vector<glm::vec4> plane_intersections(std::vector<glm::vec4> normals) {
return results;
}
std::vector<std::vector<int>> combinations(int N, int K) {
std::string bitmask(K, 1); // K leading 1's
bitmask.resize(N, 0); // N-K trailing 0's
std::vector<std::vector<int>> combos{};
do {
std::vector<int> combo{};
for (int i = 0; i < N; ++i) // [0..N-1] integers
{
if (bitmask[i]) {
combo.push_back(i);
}
}
combos.push_back(combo);
} while (std::prev_permutation(bitmask.begin(), bitmask.end()));
return combos;
}