diff --git a/vis/CMakeLists.txt b/vis/CMakeLists.txt
index 12f2dd9..394e3c0 100644
--- a/vis/CMakeLists.txt
+++ b/vis/CMakeLists.txt
@@ -12,3 +12,6 @@ add_executable(vis src/main.cpp)
 target_include_directories(vis PRIVATE include)
 target_link_libraries(vis PRIVATE tc glad glm glfw)
 add_dependencies(vis shaders)
+
+add_executable(ctest src/combotest.cpp)
+target_include_directories(ctest PRIVATE include)
diff --git a/vis/include/combo_iterator.hpp b/vis/include/combo_iterator.hpp
index 8890bee..49bdb5c 100644
--- a/vis/include/combo_iterator.hpp
+++ b/vis/include/combo_iterator.hpp
@@ -1,38 +1,43 @@
 #pragma once
 
+#include <vector>
 #include <array>
 #include <algorithm>
 #include <numeric>
 #include <stdexcept>
 
-template<size_t N, size_t K>
+size_t choose(size_t n, size_t k) {
+    if (k == 0) return 1;
+    return n * choose(n - 1, k - 1) / k;
+}
+
+template<class T>
 class ComboIterator {
-    static_assert(N > K, "N must be larger than K");
+private:
+    const std::vector<T> &options;
 
-public:
-    size_t at;
-    std::array<bool, N> bits;
-    std::array<size_t, K> curr;
+    std::vector<bool> bits;
+    std::vector<T> curr;
+    int at;
 
-    void inc() {
-        std::prev_permutation(bits.begin(), bits.end());
-        for (int i = 0, k = 0; i < N; ++i) {
-            if (bits[i]) curr[k++] = i;
+    void set_curr() {
+        for (int i = 0, j = 0; i < bits.size(); ++i) {
+            if (bits[i]) curr[j++] = options[i];
         }
-        at++;
     }
 
 public:
-    ComboIterator(size_t at = 0) : at(at), bits(), curr() {
-        std::iota(curr.begin(), curr.end(), 0);
-        std::fill(bits.begin(), bits.begin() + K, true);
+    ComboIterator(const std::vector<T> &options, int k, int at = 0)
+        : options(options), bits(options.size()), curr(k), at(at) {
+        std::fill(bits.begin(), bits.begin() + k, true);
+        set_curr();
     }
 
-    [[nodiscard]] bool operator==(const ComboIterator<N, K> &o) const {
+    [[nodiscard]] bool operator==(const ComboIterator<T> &o) const {
         return at == o.at;
     }
 
-    [[nodiscard]] bool operator!=(const ComboIterator<N, K> &o) const {
+    [[nodiscard]] bool operator!=(const ComboIterator<T> &o) const {
         return at != o.at;
     }
 
@@ -40,36 +45,41 @@ public:
         return curr;
     }
 
-    const auto *operator->() const {
-        return &curr;
+    const auto &operator->() const {
+        return &this;
     }
 
     auto operator++(int) {
-        auto res = *this;
-        inc();
-        return res;
+        std::prev_permutation(bits.begin(), bits.end());
+        set_curr();
+        ++at;
+        return *this;
     }
 
     auto operator++() &{
-        inc();
-        return *this;
+        auto res = *this;
+        (*this)++;
+        return res;
     }
 };
 
-size_t choose(size_t n, size_t k) {
-    if (k == 0) return 1;
-    return n * choose(n - 1, k - 1) / k;
-}
-
-template<size_t N, size_t K>
+template<class T>
 class Combos {
 private:
+    const std::vector<T> options;
+    int k;
+    int size;
+
 public:
-    auto begin() const {
-        return ComboIterator<N, K>();
+    Combos(const std::vector<T> &options, int k)
+        : options(options), k(k), size(choose(options.size(), k)) {
     }
 
-    auto end() const {
-        return ComboIterator<N, K>(choose(N, K));
+    ComboIterator<T> begin() const {
+        return ComboIterator<T>(options, k);
+    }
+
+    ComboIterator<T> end() const {
+        return ComboIterator<T>(options, k, size);
     }
 };
diff --git a/vis/src/combotest.cpp b/vis/src/combotest.cpp
index 9eb1976..6438fba 100644
--- a/vis/src/combotest.cpp
+++ b/vis/src/combotest.cpp
@@ -1,275 +1,15 @@
-#include <glad/glad.h>
-#include <GLFW/glfw3.h>
-#include <cmath>
+#include <combo_iterator.hpp>
 #include <iostream>
 
-#include <glm/gtc/type_ptr.hpp>
+int main() {
+    auto cs = Combos<int>({7, 2, 3}, 2);
 
-#include <tc/groups.hpp>
+    auto beg = cs.begin();
+    auto end = cs.end();
 
-#include "util.hpp"
-#include "mirror.hpp"
-#include "geometry.hpp"
-
-#include <cgl/vertexarray.hpp>
-#include <cgl/shaderprogram.hpp>
-#include <cgl/pipeline.hpp>
-#include <random>
-
-#include <chrono>
-
-#ifdef _WIN32
-extern "C" {
-__attribute__((unused)) __declspec(dllexport) int NvOptimusEnablement = 0x00000001;
-}
-#endif
-
-struct Matrices {
-    glm::mat4 proj;
-    glm::mat4 view;
-
-    Matrices(const glm::mat4 &proj, const glm::mat4 &view)
-        : proj(proj), view(view) {
-    }
-};
-
-template<unsigned N>
-struct Drawable {
-    GLenum mode{};
-    cgl::VertexArray vao{};
-    cgl::Buffer<Primitive<N>> ibo{};
-
-    Drawable(GLenum mode) : mode(mode), vao(), ibo() {}
-
-    Drawable(Drawable &) = delete;
-
-    Drawable(Drawable &&) = delete;
-
-    void draw_deferred() {
-        vao.bound([&]() {
-            glDrawArrays(GL_POINTS, 0, ibo.count() * N);
-        });
-    }
-
-    void draw_direct() {
-        vao.bound([&]() {
-            ibo.bound(GL_ELEMENT_ARRAY_BUFFER, [&]() {
-                glDrawElements(mode, ibo.count() * N, GL_UNSIGNED_INT, nullptr);
-            });
-        });
-    }
-};
-
-class Slice {
-
-};
-
-Matrices build(GLFWwindow *window, float st) {
-    int width, height;
-    glfwGetFramebufferSize(window, &width, &height);
-
-    auto aspect = (float) width / (float) height;
-    auto pheight = 1.4f;
-    auto pwidth = aspect * pheight;
-    glm::mat4 proj = glm::ortho(-pwidth, pwidth, -pheight, pheight, -10.0f, 10.0f);
-
-    auto view = glm::identity<glm::mat4>();
-    view *= utilRotate(0, 1, st * .40f);
-    view *= utilRotate(0, 2, st * .20f);
-    view *= utilRotate(0, 3, st * 1.30f);
-    view *= utilRotate(1, 2, st * .50f);
-    view *= utilRotate(1, 3, st * .25f);
-    view *= utilRotate(2, 3, st * 1.42f);
-
-    return Matrices(proj, view);
-}
-
-template<unsigned N, class T>
-auto hull(const tc::Group &group, T all_sg_gens) {
-    std::vector<std::vector<Primitive<N>>> parts;
-    auto g_gens = gens(group);
-    for (const auto &sg_gens : all_sg_gens) {
-        const auto &base = triangulate<N>(group, sg_gens);
-        const auto &tiles = each_tile(base, group, g_gens, sg_gens);
-        for (const auto &tile : tiles) {
-            parts.push_back(tile);
-        }
-    }
-    return parts;
-}
-
-template<unsigned N>
-auto full_hull(const tc::Group &group) {
-    auto g_gens = gens(group);
-//    const Combos<int> &combos = Combos(g_gens, N - 1);
-//    return hull<N, Combos<int>>(group, combos);
-}
-
-class Shaders {
-public:
-    cgl::pgm::vert defer = cgl::pgm::vert::file(
-        "shaders/slice/deferred.vs.glsl");
-    cgl::pgm::vert direct_ortho = cgl::pgm::vert::file(
-        "shaders/direct-ortho.vs.glsl");
-    cgl::pgm::vert direct_stereo = cgl::pgm::vert::file(
-        "shaders/direct-stereo.vs.glsl");
-
-    cgl::pgm::geom slice = cgl::pgm::geom::file(
-        "shaders/slice/slice.gm.glsl");
-    cgl::pgm::geom curve_stereo = cgl::pgm::geom::file(
-        "shaders/curve-stereo.gm.glsl");
-    cgl::pgm::geom curve_ortho = cgl::pgm::geom::file(
-        "shaders/curve-ortho.gm.glsl");
-
-    cgl::pgm::frag solid = cgl::pgm::frag::file(
-        "shaders/solid.fs.glsl");
-    cgl::pgm::frag diffuse = cgl::pgm::frag::file(
-        "shaders/diffuse.fs.glsl");
-};
-
-std::vector<vec4> points(const tc::Group &group, const std::vector<float> &coords) {
-    auto cosets = group.solve();
-    auto mirrors = mirror<5>(group);
-
-    auto corners = plane_intersections(mirrors);
-
-    auto start = barycentric(corners, coords);
-
-    auto higher = cosets.path.walk<vec5, vec5>(start, mirrors, reflect<vec5>);
-    std::vector<vec4> res(higher.size());
-    std::transform(higher.begin(), higher.end(), res.begin(), stereo<4>);
-
-    return res;
-}
-
-void run(GLFWwindow *window) {
-    glEnable(GL_PROGRAM_POINT_SIZE);
-    glEnable(GL_POINT_SMOOTH);
-    glEnable(GL_DEPTH_TEST);
-//    glEnable(GL_CULL_FACE);
-    glCullFace(GL_BACK);
-    glEnable(GL_BLEND);
-    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-
-    Shaders sh;
-
-    auto proj_pipe = cgl::pipeline();
-    proj_pipe
-        .stage(sh.direct_stereo)
-        .stage(sh.solid);
-
-    auto slice_pipe = cgl::pipeline();
-    slice_pipe
-        .stage(sh.defer)
-        .stage(sh.slice)
-        .stage(sh.solid);
-
-    auto group = tc::schlafli({5, 3, 3, 2});
-//    std::cout << group.solve({}).size() << std::endl;
-//    const auto &all = merge(full_hull<4>(group));
-//    std::cout << all.size() / sizeof(Primitive<4>) << std::endl;
-//    const auto &one = merge(full_hull<4>(tc::schlafli({5, 3, 3})));
-//    std::cout << one.size() / sizeof(Primitive<4>) << std::endl;
-
-
-    auto slice_faces = hull<4>(group, (std::vector<std::vector<int>>) {
-        {0, 1, 2},
-        {0, 1, 4},
-        {0, 2, 4},
-        {1, 2, 4},
-
-//        {0, 1, 2,},
-//        {0, 1, 3,},
-//        {0, 2, 3,},
-//        {1, 2, 3,},
-    });
-    auto slice_face_data = merge<4>(slice_faces);
-
-    auto slice_edges = hull<4>(group, (std::vector<std::vector<int>>) {
-        {0, 1, 3},
-        {0, 1, 4},
-        {0, 2, 3},
-        {0, 2, 4},
-        {1, 2, 3},
-        {1, 2, 4},
-        {1, 3, 4},
-    });
-    auto slice_edge_data = merge<4>(slice_edges);
-
-    Drawable<4> edges(GL_POINTS);
-    edges.ibo.put(slice_edge_data);
-    edges.vao.ipointer(0, edges.ibo, 4, GL_UNSIGNED_INT);
-
-    Drawable<4> faces(GL_POINTS);
-    faces.ibo.put(slice_face_data);
-    faces.vao.ipointer(0, faces.ibo, 4, GL_UNSIGNED_INT);
-
-    auto pbo_white = cgl::Buffer<vec4>(points(group, {0.3f, 0.12f, 0.12f, 0.12f, 0.025f}));
-    auto pbo_black = cgl::Buffer<vec4>();
-
-    auto ubo = cgl::Buffer<Matrices>();
-    glBindBufferBase(GL_UNIFORM_BUFFER, 1, ubo);
-
-    while (!glfwWindowShouldClose(window)) {
-        auto time = (float) glfwGetTime();
-        pbo_black.put(points(group, {0.5f, 0.1f, 0.1f, 0.1f, sinf(time / 2)}));
-
-        int width, height;
-        glfwGetFramebufferSize(window, &width, &height);
-        glViewport(0, 0, width, height);
-
-        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-
-        auto st = time / 16 - 1;
-        Matrices mats = build(window, st);
-        ubo.put(mats);
-
-        glLineWidth(1.5);
-
-        slice_pipe.bound([&]() {
-            glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, pbo_black);
-            glProgramUniform4f(sh.solid, 2, 0.3, 0.3, 0.3, 1.0);
-            edges.draw_deferred();
-
-            glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, pbo_white);
-            glProgramUniform4f(sh.solid, 2, 1.0, 1.0, 1.0, 1.0);
-            faces.draw_deferred();
-        });
-
-        glfwSwapInterval(2);
-        glfwSwapBuffers(window);
-
-        glfwPollEvents();
+    while (beg != end) {
+        const auto &c = *(++beg);
+        for (const auto &e : c) std::cout << e << " ";
+        std::cout << std::endl;
     }
 }
-
-int main(int argc, char *argv[]) {
-    if (!glfwInit()) {
-        std::cerr << "Failed to initialize GLFW" << std::endl;
-        return EXIT_FAILURE;
-    }
-
-    auto window = glfwCreateWindow(
-        1280, 720,
-        "Coset Visualization",
-        nullptr, nullptr);
-
-    if (!window) {
-        std::cerr << "Failed to create window" << std::endl;
-        glfwTerminate();
-        exit(EXIT_FAILURE);
-    }
-
-    glfwMakeContextCurrent(window);
-    gladLoadGLLoader((GLADloadproc) glfwGetProcAddress);
-    glfwSwapInterval(1);
-    glClear(GL_COLOR_BUFFER_BIT);
-    glfwSwapBuffers(window);
-
-    std::cout << utilInfo();
-
-    run(window);
-
-    glfwTerminate();
-    return EXIT_SUCCESS;
-}
diff --git a/vis/src/main.cpp b/vis/src/main.cpp
index fa88957..0bbeaa2 100644
--- a/vis/src/main.cpp
+++ b/vis/src/main.cpp
@@ -60,12 +60,6 @@ struct Drawable {
     }
 };
 
-float factor(unsigned index, unsigned size) {
-    auto num = (float) index;
-    auto den = size > 1 ? (float) size - 1 : 1;
-    return num / den;
-}
-
 Matrices build(GLFWwindow *window, float st) {
     int width, height;
     glfwGetFramebufferSize(window, &width, &height);
@@ -100,13 +94,6 @@ auto hull(const tc::Group &group, T all_sg_gens) {
     return parts;
 }
 
-template<unsigned N>
-auto full_hull(const tc::Group &group) {
-    auto g_gens = gens(group);
-    const Combos<int> &combos = Combos(g_gens, N - 1);
-    return hull<N, Combos<int>>(group, combos);
-}
-
 class Shaders {
 public:
     cgl::pgm::vert defer = cgl::pgm::vert::file(
@@ -168,16 +155,15 @@ void run(GLFWwindow *window) {
 
     auto group = tc::schlafli({5, 3, 3, 2});
 
-//    auto wire_data = full_hull<2>(group);
-
-    //    slice_parts.erase(slice_parts.end() - 1, slice_parts.end());
     auto slice_faces = hull<4>(group, (std::vector<std::vector<int>>) {
         {0, 1, 2},
     });
+
     unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
     std::default_random_engine rand(seed);
     std::shuffle(slice_faces.begin(), slice_faces.end(), rand);
     slice_faces.erase(slice_faces.begin(), slice_faces.begin() + slice_faces.size() / 2);
+
     auto slice_face_data = merge<4>(slice_faces);
     auto slice_edges = hull<4>(group, (std::vector<std::vector<int>>) {
         {0, 1, 3},
@@ -190,9 +176,6 @@ void run(GLFWwindow *window) {
     });
     auto slice_edge_data = merge<4>(slice_edges);
 
-//    Drawable<2> wires(GL_LINES);
-//    wires.ibo.put(wire_data);
-
     Drawable<4> edges(GL_POINTS);
     edges.ibo.put(slice_edge_data);
     edges.vao.ipointer(0, edges.ibo, 4, GL_UNSIGNED_INT);
@@ -230,11 +213,6 @@ void run(GLFWwindow *window) {
             faces.draw_deferred();
         });
 
-//        proj_pipe.bound([&]() {
-//            glProgramUniform4f(sh.solid, 2, 0.3, 0.3, 0.3, 0.4);
-//            wires.draw_direct();
-//        });
-
         glfwSwapInterval(2);
         glfwSwapBuffers(window);
 
@@ -243,7 +221,6 @@ void run(GLFWwindow *window) {
 }
 
 int main(int argc, char *argv[]) {
-    //region init window
     if (!glfwInit()) {
         std::cerr << "Failed to initialize GLFW" << std::endl;
         return EXIT_FAILURE;
@@ -265,7 +242,6 @@ int main(int argc, char *argv[]) {
     glfwSwapInterval(1);
     glClear(GL_COLOR_BUFFER_BIT);
     glfwSwapBuffers(window);
-    //endregion
 
     std::cout << utilInfo();