reduce duplicated list of elements

- made tag_tuple able to instantiate any template type that accepts the same template parameters as the tag_tuple
- suffix element_tags and tool_tags with `_t` to denote that they are types and not variables

.gitignore

@@ -48,3 +48,6 @@ Release/
 *.sln
 *.filters
 *.user
+
+# Save files for Circuit Playground
+*.sav

CircuitPlayground/gamestate.hpp

@@ -20,10 +20,13 @@
 
 class GameState {
 private:
+
+    // the possible elements that a pixel can represent
     // std::monostate is a 'default' state, which represents an empty pixel
-    using element_variant_t =     std::variant<std::monostate, ConductiveWire, InsulatedWire, Signal, Source, PositiveRelay, NegativeRelay, AndGate, OrGate, NandGate, NorGate>;
-    // for consistency, the element order in this tag_tuple should be the same as the variant above
-    using element_tags = extensions::tag_tuple<std::monostate, ConductiveWire, InsulatedWire, Signal, Source, PositiveRelay, NegativeRelay, AndGate, OrGate, NandGate, NorGate>;
+    using element_tags_t = extensions::tag_tuple<std::monostate, ConductiveWire, InsulatedWire, Signal, Source, PositiveRelay, NegativeRelay, AndGate, OrGate, NandGate, NorGate>;
+
+    using element_variant_t = element_tags_t::instantiate<std::variant>;
+
     extensions::heap_matrix<element_variant_t> dataMatrix;
 
     friend class StateManager;

CircuitPlayground/mainwindow.hpp

@@ -19,7 +19,7 @@ class MainWindow {
 public:
 
     // compile-time type tag which stores the list of available elements
-    using tool_tags = extensions::tag_tuple<Selector, Panner, Eraser, ConductiveWire, InsulatedWire, Signal, Source, PositiveRelay, NegativeRelay, AndGate, OrGate, NandGate, NorGate>;
+    using tool_tags_t = extensions::tag_tuple<Selector, Panner, Eraser, ConductiveWire, InsulatedWire, Signal, Source, PositiveRelay, NegativeRelay, AndGate, OrGate, NandGate, NorGate>;
 
     // logical units
     constexpr static int LOGICAL_TOOLBOX_WIDTH = 128;

CircuitPlayground/playarea.cpp

@@ -93,7 +93,7 @@ void PlayArea::processMouseMotionEvent(const SDL_MouseMotionEvent& event) {
         int offsetY = physicalOffsetY - translationY;
         offsetX = extensions::div_floor(offsetX, scale);
         offsetY = extensions::div_floor(offsetY, scale);
-        MainWindow::tool_tags::get(mainWindow.selectedToolIndices[*drawingIndex], [this, offsetX, offsetY](const auto tool_tag) {
+        MainWindow::tool_tags_t::get(mainWindow.selectedToolIndices[*drawingIndex], [this, offsetX, offsetY](const auto tool_tag) {
             using Tool = typename decltype(tool_tag)::type;
             if constexpr (std::is_base_of_v<Pencil, Tool>) {
                 processDrawingTool<Tool>(offsetX, offsetY);
@@ -126,7 +126,7 @@ void PlayArea::processMouseButtonEvent(const SDL_MouseButtonEvent& event) {
     offsetY = extensions::div_floor(offsetY, scale);
 
     size_t inputHandleIndex = MainWindow::resolveInputHandleIndex(event);
-    MainWindow::tool_tags::get(mainWindow.selectedToolIndices[inputHandleIndex], [this, event, offsetX, offsetY, inputHandleIndex](const auto tool_tag) {
+    MainWindow::tool_tags_t::get(mainWindow.selectedToolIndices[inputHandleIndex], [this, event, offsetX, offsetY, inputHandleIndex](const auto tool_tag) {
         // 'Tool' is the type of tool (e.g. Selector)
         using Tool = typename decltype(tool_tag)::type;
 

CircuitPlayground/statemanager.cpp

@@ -94,7 +94,7 @@ void StateManager::readSave() {
             saveFile.read(reinterpret_cast<char*>(&element_index), sizeof element_index);
 
             GameState::element_variant_t element;
-            GameState::element_tags::get(element_index, [&element](const auto element_tag) {
+            GameState::element_tags_t::get(element_index, [&element](const auto element_tag) {
                 using Element = typename decltype(element_tag)::type;
                 element = Element();
             });
@@ -115,7 +115,7 @@ void StateManager::writeSave() {
     for (int32_t y = 0; y != gameState.dataMatrix.height(); ++y) {
         for (int32_t x = 0; x != gameState.dataMatrix.width(); ++x) {
             GameState::element_variant_t element = gameState.dataMatrix[{x, y}];
-            GameState::element_tags::for_each([&element, &saveFile](const auto element_tag, const auto index_tag) {
+            GameState::element_tags_t::for_each([&element, &saveFile](const auto element_tag, const auto index_tag) {
                 size_t index = element.index();
                 if (index == decltype(index_tag)::value) {
                     saveFile.write(reinterpret_cast<char*>(&index), sizeof index);

CircuitPlayground/tag_tuple.hpp

@@ -62,14 +62,20 @@ namespace extensions {
 
 
         /**
-        * Invokes callback(tag<T>) for the T at the given index.
-        * If index is out of bounds, then callback will not be invoked.
-        */
+         * Invokes callback(tag<T>) for the T at the given index.
+         * If index is out of bounds, then callback will not be invoked.
+         */
         template <typename Callback>
         inline static void get(const size_t index, Callback&& callback) {
             get_by_index<0>(index, std::forward<Callback>(callback));
         }
 
+        /**
+         * Generic template instantiation helper
+         */
+        template <template <typename...> typename TemplateType>
+        using instantiate = TemplateType<T...>;
+
     };
 
 }

CircuitPlayground/toolbox.cpp

@@ -64,10 +64,10 @@ void Toolbox::render(SDL_Renderer* renderer) const {
 
 
     // draw the buttons to the screen one-by-one
-    MainWindow::tool_tags::for_each([this, renderer, button_font](const auto tool_tag, const auto index_tag) {
+    MainWindow::tool_tags_t::for_each([this, renderer, button_font](const auto tool_tag, const auto index_tag) {
         // 'Tool' is the type of tool (e.g. ConductiveWire)
         using Tool = typename decltype(tool_tag)::type;
-        // 'index' is the index of this element inside the tool_tags
+        // 'index' is the index of this element inside the tool_tags_t
         constexpr size_t index = decltype(index_tag)::value;
 
         SDL_Color backgroundColorForText = MainWindow::backgroundColor;
@@ -116,7 +116,7 @@ void Toolbox::processMouseMotionEvent(const SDL_MouseMotionEvent& event) {
 
     // element index
     size_t index = static_cast<size_t>((offsetY - PADDING_VERTICAL) / (BUTTON_HEIGHT + BUTTON_SPACING));
-    if (index >= MainWindow::tool_tags::size) return;
+    if (index >= MainWindow::tool_tags_t::size) return;
 
     // check if the mouse is on the button spacing instead of on the actual button
     if ((offsetY - PADDING_VERTICAL) - static_cast<int32_t>(index) * (BUTTON_HEIGHT + BUTTON_SPACING) >= BUTTON_HEIGHT) return;
@@ -136,7 +136,7 @@ void Toolbox::processMouseButtonDownEvent(const SDL_MouseButtonEvent& event) {
 
     // element index
     size_t index = static_cast<size_t>((offsetY - PADDING_VERTICAL) / (BUTTON_HEIGHT + BUTTON_SPACING));
-    if (index >= MainWindow::tool_tags::size) return;
+    if (index >= MainWindow::tool_tags_t::size) return;
 
     // check if the mouse is on the button spacing instead of on the actual button
     if ((offsetY - PADDING_VERTICAL) - static_cast<int32_t>(index) * (BUTTON_HEIGHT + BUTTON_SPACING) >= BUTTON_HEIGHT) return;