diff --git a/templates/1_convolve_simple.cpp b/examples/1_convolve_simple.cpp
similarity index 100%
rename from templates/1_convolve_simple.cpp
rename to examples/1_convolve_simple.cpp
diff --git a/templates/2_convolve_overlap_save.cpp b/examples/2_convolve_overlap_save.cpp
similarity index 100%
rename from templates/2_convolve_overlap_save.cpp
rename to examples/2_convolve_overlap_save.cpp
diff --git a/templates/3_fir.cpp b/examples/3_fir.cpp
similarity index 100%
rename from templates/3_fir.cpp
rename to examples/3_fir.cpp
diff --git a/templates/4_fir_pro.cpp b/examples/4_fir_pro.cpp
similarity index 100%
rename from templates/4_fir_pro.cpp
rename to examples/4_fir_pro.cpp
diff --git a/templates/5_fir_differentiator.cpp b/examples/5_fir_differentiator.cpp
similarity index 100%
rename from templates/5_fir_differentiator.cpp
rename to examples/5_fir_differentiator.cpp
diff --git a/templates/6_iir_test.cpp b/examples/6_iir_test.cpp
similarity index 100%
rename from templates/6_iir_test.cpp
rename to examples/6_iir_test.cpp
diff --git a/templates/7_iir_echo.cpp b/examples/7_iir_echo.cpp
similarity index 100%
rename from templates/7_iir_echo.cpp
rename to examples/7_iir_echo.cpp
diff --git a/source/circular.hpp b/source/circular.hpp
index 33b8ee0..6b82068 100644
--- a/source/circular.hpp
+++ b/source/circular.hpp
@@ -1,3 +1,14 @@
+/**
+ * @file circular.hpp
+ * @brief Small utility for filling a buffer in a circular manner.
+ *
+ * Copyright (C) 2021 Clyne Sullivan
+ *
+ * Distributed under the GNU GPL v3 or later. You should have received a copy of
+ * the GNU General Public License along with this program.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
 #ifndef CIRCULAR_HPP
 #define CIRCULAR_HPP
 
diff --git a/source/code.cpp b/source/code.cpp
index 7a9afaa..14f603c 100644
--- a/source/code.cpp
+++ b/source/code.cpp
@@ -1,3 +1,14 @@
+/**
+ * @file code.cpp
+ * @brief Functionality for compiling and disassembling source code.
+ *
+ * Copyright (C) 2021 Clyne Sullivan
+ *
+ * Distributed under the GNU GPL v3 or later. You should have received a copy of
+ * the GNU General Public License along with this program.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
 #include "stmdsp.hpp"
 #include "stmdsp_code.hpp"
 
@@ -9,10 +20,13 @@
 #include <string>
 
 extern std::shared_ptr<stmdsp::device> m_device;
-extern void log(const std::string& str);
+void log(const std::string& str);
 
-std::string tempFileName; // device.cpp
+std::ifstream compileOpenBinaryFile();
+void compileEditorCode(const std::string& code);
+void disassembleCode();
 
+static std::string tempFileName;
 static std::string newTempFileName();
 static bool codeExecuteCommand(
     const std::string& command,
@@ -22,6 +36,14 @@ static void stringReplaceAll(
     const std::string& what,
     const std::string& with);
 
+std::ifstream compileOpenBinaryFile()
+{
+    if (!tempFileName.empty())
+        return std::ifstream(tempFileName + ".o");
+    else
+        return std::ifstream();
+}
+
 void compileEditorCode(const std::string& code)
 {
     log("Compiling...");
diff --git a/source/device.cpp b/source/device.cpp
index abcc88a..11e181e 100644
--- a/source/device.cpp
+++ b/source/device.cpp
@@ -30,9 +30,9 @@
 #include <thread>
 #include <vector>
 
-extern std::string tempFileName;
 extern void log(const std::string& str);
 extern std::vector<stmdsp::dacsample_t> deviceGenLoadFormulaEval(const std::string&);
+extern std::ifstream compileOpenBinaryFile();
 
 std::shared_ptr<stmdsp::device> m_device;
 
@@ -224,15 +224,21 @@ void deviceLoadLogFile(const std::string& file)
 bool deviceGenStartToggle()
 {
     if (m_device) {
-        bool running = m_device->is_siggening();
+        const bool running = m_device->is_siggening();
+
         if (!running) {
-            if (wavOutput.valid())
+            if (wavOutput.valid()) {
                 std::thread(feedSigGenTask, m_device).detach();
-            else
+            } else {
+                std::scoped_lock dlock (mutexDeviceLoad);
                 m_device->siggen_start();
+            }
             log("Generator started.");
         } else {
-            m_device->siggen_stop();
+            {
+                std::scoped_lock dlock (mutexDeviceLoad);
+                m_device->siggen_stop();
+            }
             log("Generator stopped.");
         }
 
@@ -332,7 +338,7 @@ void deviceAlgorithmUpload()
         log("No device connected.");
     } else if (m_device->is_running()) {
         log("Cannot upload algorithm while running.");
-    } else if (std::ifstream algo (tempFileName + ".o"); algo.is_open()) {
+    } else if (auto algo = compileOpenBinaryFile(); algo.is_open()) {
         std::ostringstream sstr;
         sstr << algo.rdbuf();
         auto str = sstr.str();
diff --git a/source/device_formula.cpp b/source/device_formula.cpp
index c94eab7..a70f465 100644
--- a/source/device_formula.cpp
+++ b/source/device_formula.cpp
@@ -1,31 +1,63 @@
+/**
+ * @file device_formula.cpp
+ * @brief Function for filling generator buffer using a mathematical formula.
+ * This is kept in its own file as exprtk.hpp takes forever to compile.
+ *
+ * Copyright (C) 2021 Clyne Sullivan
+ *
+ * Distributed under the GNU GPL v3 or later. You should have received a copy of
+ * the GNU General Public License along with this program.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
 #include "stmdsp.hpp"
 #include "exprtk.hpp"
 
 #include <algorithm>
+#include <random>
 #include <string_view>
 #include <vector>
 
+static std::random_device randomDevice;
+
 std::vector<stmdsp::dacsample_t> deviceGenLoadFormulaEval(const std::string& formulaString)
 {
     double x = 0;
 
     exprtk::symbol_table<double> symbol_table;
+    exprtk::function_compositor<double> compositor (symbol_table);
     exprtk::expression<double> expression;
     exprtk::parser<double> parser;
 
-    symbol_table.add_variable("x", x);
     symbol_table.add_constants();
+    symbol_table.add_variable("x", x);
+    symbol_table.add_function("random",
+        [](double l, double h) -> double {
+            return std::uniform_real_distribution<double>(l, h)(randomDevice);
+        });
+    compositor.add(exprtk::function_compositor<double>::function()
+                       .name("square")
+                       .var("X")
+                       .expression("ceil(sin(pi*X))"));
+    compositor.add(exprtk::function_compositor<double>::function()
+                       .name("triangle")
+                       .var("X")
+                       .expression("ceil(sin(pi*X))*(X-floor(X))+ceil(-sin(pi*X))*(-X-floor(-X))"));
+    compositor.add(exprtk::function_compositor<double>::function()
+                       .name("pulse")
+                       .var("L")
+                       .var("X")
+                       .expression("if(X<=L,1,0)"));
     expression.register_symbol_table(symbol_table);
     parser.compile(formulaString, expression);
 
-    std::vector<stmdsp::dacsample_t> samples (stmdsp::SAMPLES_MAX);
-
-    auto genFun = [&x, &expression] {
-        stmdsp::dacsample_t s = expression.value();
+    const auto genFun = [&x, &expression] {
+        const auto s = std::clamp(expression.value(), -1., 1.) * 2048. + 2048.;
         ++x;
-        return s;
+        return static_cast<stmdsp::dacsample_t>(std::min(s, 4095.));
     };
 
+    std::vector<stmdsp::dacsample_t> samples (stmdsp::SAMPLES_MAX);
     std::generate(samples.begin(), samples.end(), genFun);
     return samples;
 }
diff --git a/source/file.cpp b/source/file.cpp
index a5ef1d8..fe5dafb 100644
--- a/source/file.cpp
+++ b/source/file.cpp
@@ -40,7 +40,7 @@ enum class FileAction {
 
 static FileAction fileAction = FileAction::None;
 static std::string fileCurrentPath;
-static std::vector<std::filesystem::path> fileTemplateList;
+static std::vector<std::filesystem::path> fileExampleList;
 
 static void saveCurrentFile()
 {
@@ -66,9 +66,9 @@ static void openNewFile()
     editor.SetText(stmdsp::file_content);
 }
 
-static std::vector<std::filesystem::path> fileScanTemplates()
+static std::vector<std::filesystem::path> fileScanExamples()
 {
-    const auto path = std::filesystem::current_path() / "templates";
+    const auto path = std::filesystem::current_path() / "examples";
     const std::filesystem::recursive_directory_iterator rdi (path);
 
     std::vector<std::filesystem::path> list;
@@ -83,7 +83,7 @@ static std::vector<std::filesystem::path> fileScanTemplates()
 
 void fileInit()
 {
-    fileTemplateList = fileScanTemplates();
+    fileExampleList = fileScanExamples();
     openNewFile();
 }
 
@@ -102,8 +102,8 @@ void fileRenderMenu()
                 "ChooseFileOpenSave", "Choose File", ".cpp", ".");
         }
 
-        if (ImGui::BeginMenu("Open Template")) {
-            for (const auto& file : fileTemplateList) {
+        if (ImGui::BeginMenu("Open Example")) {
+            for (const auto& file : fileExampleList) {
                 if (ImGui::MenuItem(file.filename().c_str())) {
                     fileCurrentPath = file.string();
                     openCurrentFile();
diff --git a/source/gui.cpp b/source/gui.cpp
index 515d471..80120c4 100644
--- a/source/gui.cpp
+++ b/source/gui.cpp
@@ -19,15 +19,17 @@
 #include <SDL2/SDL.h>
 #include <SDL2/SDL_opengl.h>
 
-ImFont *fontSans = nullptr;
-ImFont *fontMono = nullptr;
-static ImGuiIO *io = nullptr;
+bool guiInitialize();
+void guiRender();
+bool guiHandleEvents();
+void guiShutdown();
+
 static SDL_Window *window = nullptr;
-static decltype(SDL_GL_CreateContext(nullptr)) gl_context;
+static SDL_GLContext gl_context;
 
 bool guiInitialize()
 {
-    if (SDL_Init(/*SDL_INIT_VIDEO*/0) != 0) {
+    if (SDL_Init(0) != 0) {
         printf("Error: %s\n", SDL_GetError());
         return false;
     }
@@ -42,6 +44,12 @@ bool guiInitialize()
         SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
         WINDOW_WIDTH, WINDOW_HEIGHT,
         SDL_WINDOW_OPENGL /*| SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI*/);
+
+    if (window == nullptr) {
+        puts("Error: Could not create the window!");
+        return false;
+    }
+
     gl_context = SDL_GL_CreateContext(window);
     SDL_GL_MakeCurrent(window, gl_context);
     SDL_GL_SetSwapInterval(1); // Enable vsync
@@ -49,10 +57,7 @@ bool guiInitialize()
     // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
-    io = &ImGui::GetIO();
     //io->ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
-    fontSans = io->Fonts->AddFontFromFileTTF("fonts/Roboto-Regular.ttf", 20);
-    fontMono = io->Fonts->AddFontFromFileTTF("fonts/RobotoMono-Regular.ttf", 20);
 
     ImGui_ImplSDL2_InitForOpenGL(window, gl_context);
     ImGui_ImplOpenGL2_Init();
@@ -99,13 +104,19 @@ bool guiInitialize()
     return true;
 }
 
-void guiRender(void (*func)())
+void guiRender()
 {
-   glViewport(0, 0, (int)io->DisplaySize.x, (int)io->DisplaySize.y);
-   glClearColor(1, 1, 1, 1);
-   glClear(GL_COLOR_BUFFER_BIT);
-   func();
-   SDL_GL_SwapWindow(window);
+    ImGui::Render();
+
+    const auto& displaySize = ImGui::GetIO().DisplaySize;
+    const int sizeX = static_cast<int>(displaySize.x);
+    const int sizeY = static_cast<int>(displaySize.y);
+
+    glViewport(0, 0, sizeX, sizeY);
+    glClearColor(1, 1, 1, 1);
+    glClear(GL_COLOR_BUFFER_BIT);
+    ImGui_ImplOpenGL2_RenderDrawData(ImGui::GetDrawData());
+    SDL_GL_SwapWindow(window);
 }
 
 bool guiHandleEvents()
@@ -114,10 +125,14 @@ bool guiHandleEvents()
 
     for (SDL_Event event; SDL_PollEvent(&event);) {
         ImGui_ImplSDL2_ProcessEvent(&event);
-        if (event.type == SDL_QUIT)
-            done = true;
-        if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(window))
+        if (event.type == SDL_QUIT) {
             done = true;
+        } else if (event.type == SDL_WINDOWEVENT) {
+            const auto& ew = event.window;
+            const auto wid = SDL_GetWindowID(window);
+            if (ew.event == SDL_WINDOWEVENT_CLOSE && ew.windowID == wid)
+                done = true;
+        }
     }
 
     return done;
diff --git a/source/gui_code.cpp b/source/gui_code.cpp
index 6917c72..19fa572 100644
--- a/source/gui_code.cpp
+++ b/source/gui_code.cpp
@@ -37,9 +37,9 @@ void codeEditorInit()
 void codeRenderMenu()
 {
     if (ImGui::BeginMenu("Code")) {
-        if (ImGui::MenuItem("Compile code"))
+        if (ImGui::MenuItem("Compile"))
             codeCompile();
-        if (ImGui::MenuItem("Show disassembly"))
+        if (ImGui::MenuItem("Disassemble"))
             codeDisassemble();
 
         ImGui::EndMenu();
diff --git a/source/gui_device.cpp b/source/gui_device.cpp
index a1d0555..43c0a58 100644
--- a/source/gui_device.cpp
+++ b/source/gui_device.cpp
@@ -55,7 +55,7 @@ void deviceRenderMenu()
         }
     };
 
-    if (ImGui::BeginMenu("Run")) {
+    if (ImGui::BeginMenu("Device")) {
         static std::string connectLabel ("Connect");
         addMenuItem(connectLabel, !m_device || !m_device->is_running(), [&] {
                 if (deviceConnect()) {
@@ -199,11 +199,6 @@ void deviceRenderWidgets()
             ImGui::PopStyleColor();
         }
 
-        if (ImGui::Button("Cancel")) {
-            siggenInput.clear();
-            ImGui::CloseCurrentPopup();
-        }
-
         if (ImGui::Button("Save")) {
             switch (siggenOption) {
             case 0:
@@ -219,6 +214,12 @@ void deviceRenderWidgets()
             ImGui::CloseCurrentPopup();
         }
 
+        ImGui::SameLine();
+        if (ImGui::Button("Cancel")) {
+            siggenInput.clear();
+            ImGui::CloseCurrentPopup();
+        }
+
         ImGui::EndPopup();
     }
 
@@ -387,12 +388,22 @@ void deviceRenderDraw()
         if (mouse.x > p0.x && mouse.x < p0.x + size.x &&
             mouse.y > p0.y && mouse.y < p0.y + size.y)
         {
-            const std::size_t si = (mouse.x - p0.x) / size.x * buffer.size();
-            const float s = buffer[si] / 4095.f * 6.6f - 3.3f;
-            char buf[12];
-            snprintf(buf, 16, "   %1.3fV", s);
+            char buf[16];
             drawList->AddLine({mouse.x, p0.y}, {mouse.x, p0.y + size.y}, IM_COL32(255, 255, 0, 255));
-            drawList->AddText(ImGui::GetMousePos(), IM_COL32(210, 210, 0, 255), buf);
+
+            {
+                const std::size_t si = (mouse.x - p0.x) / size.x * buffer.size();
+                const float s = buffer[si] / 4095.f * 6.6f - 3.3f;
+                snprintf(buf, sizeof(buf), "   %1.3fV", s);
+                drawList->AddText(mouse, IM_COL32(255, 0, 0, 255), buf);
+            }
+
+            if (drawSamplesInput) {
+                const std::size_t si = (mouse.x - p0.x) / size.x * bufferInput.size();
+                const float s = bufferInput[si] / 4095.f * 6.6f - 3.3f;
+                snprintf(buf, sizeof(buf), "   %1.3fV", s);
+                drawList->AddText({mouse.x, mouse.y + 20}, IM_COL32(0, 0, 255, 255), buf);
+            }
         }
 
         ImGui::End();
diff --git a/source/imgui/TextEditor.cpp b/source/imgui/TextEditor.cpp
index b45a21e..85bff74 100644
--- a/source/imgui/TextEditor.cpp
+++ b/source/imgui/TextEditor.cpp
@@ -46,7 +46,7 @@ TextEditor::TextEditor()
 	, mHandleKeyboardInputs(true)
 	, mHandleMouseInputs(true)
 	, mIgnoreImGuiChild(false)
-	, mShowWhitespaces(true)
+	, mShowWhitespaces(false)
 	, mStartTime(std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()).count())
 {
 	SetPalette(GetDarkPalette());
diff --git a/source/logview.cpp b/source/logview.cpp
index 267cecb..5a771bf 100644
--- a/source/logview.cpp
+++ b/source/logview.cpp
@@ -41,7 +41,7 @@ void LogView::Draw(const char* title, bool* p_open, ImGuiWindowFlags flags)
     }
 
     ImGui::Text("Log ");
-    ImGui::SameLine();
+    ImGui::SameLine(ImGui::GetWindowWidth() - 120);
     if (ImGui::Button("Clear"))
         Clear();
     ImGui::SameLine();
diff --git a/source/main.cpp b/source/main.cpp
index 5eac338..e8641bc 100644
--- a/source/main.cpp
+++ b/source/main.cpp
@@ -19,37 +19,31 @@
 
 #include <chrono>
 #include <cmath>
+#include <iostream>
 #include <string>
 #include <thread>
 
-extern ImFont *fontSans;
-extern ImFont *fontMono;
-
-bool guiInitialize();
-bool guiHandleEvents();
-void guiShutdown();
-void guiRender(void (*func)());
-
-void fileRenderMenu();
-void fileRenderDialog();
-void fileInit();
-
 void codeEditorInit();
 void codeRenderMenu();
 void codeRenderToolbar();
 void codeRenderWidgets();
-
 void deviceRenderDraw();
 void deviceRenderMenu();
 void deviceRenderToolbar();
 void deviceRenderWidgets();
+void fileRenderMenu();
+void fileRenderDialog();
+void fileInit();
+bool guiInitialize();
+bool guiHandleEvents();
+void guiShutdown();
+void guiRender();
 
-static LogView logView;
+void log(const std::string& str);
 
-void log(const std::string& str)
-{
-    logView.AddLog(str);
-}
+static LogView logView;
+static ImFont *fontSans = nullptr;
+static ImFont *fontMono = nullptr;
 
 static void renderWindow();
 
@@ -58,6 +52,14 @@ int main(int, char **)
     if (!guiInitialize())
         return -1;
 
+    auto& io = ImGui::GetIO();
+    fontSans = io.Fonts->AddFontFromFileTTF("fonts/Roboto-Regular.ttf", 20);
+    fontMono = io.Fonts->AddFontFromFileTTF("fonts/RobotoMono-Regular.ttf", 20);
+    if (fontSans == nullptr || fontMono == nullptr) {
+        std::cout << "Failed to load fonts!" << std::endl;
+        return -1;
+    }
+
     codeEditorInit();
     fileInit();
 
@@ -78,6 +80,11 @@ int main(int, char **)
     return 0;
 }
 
+void log(const std::string& str)
+{
+    logView.AddLog(str);
+}
+
 void renderWindow()
 {
     // Start the new window frame and render the menu bar.
@@ -124,9 +131,6 @@ void renderWindow()
     deviceRenderDraw();
 
     // Draw everything to the screen.
-    ImGui::Render();
-    guiRender([] {
-        ImGui_ImplOpenGL2_RenderDrawData(ImGui::GetDrawData());
-    });
+    guiRender();
 }