Impl saving image with "S"

src/imgui_helper.hpp

@@ -29,6 +29,7 @@ namespace Tri {
             ImGui::Text("Press \"R\" to undo.");
             ImGui::Text("Press \"C\" to change colors");
             ImGui::Text("Press \"B\" to change background color");
+            ImGui::Text("Press \"S\" to save what was drawn as a png image");
             ImGui::End();
         }
     }
@@ -68,6 +69,26 @@ namespace Tri {
             ImGui::End();
         }
     }
+
+    inline void draw_save(Tri::State *state) {
+        if(state->get_flags().test(6)) {
+            auto *filenameBuffer = state->get_save_filename_buffer();
+            ImGui::Begin("Save");
+            ImGui::InputText("Filename", filenameBuffer->data(), filenameBuffer->size() - 1);
+            if(ImGui::Button("Save")) {
+                if(state->do_save()) {
+                    state->close_save();
+                }
+            } else if(ImGui::Button("Cancel")) {
+                state->close_save();
+            }
+            auto string_view = state->failed_save_message();
+            if(!string_view.empty()) {
+                ImGui::TextUnformatted(string_view.data(), string_view.data() + string_view.size());
+            }
+            ImGui::End();
+        }
+    }
 }
 
 #endif

src/state.cpp

@@ -2,6 +2,7 @@
 
 #include <cstring>
 #include <cassert>
+#include <string>
 
 #include <imgui-SFML.h>
 
@@ -35,6 +36,8 @@ bgColor(sf::Color::Black)
     pointCircle.setFillColor(sf::Color::White);
     pointCircle.setOutlineColor(sf::Color::Black);
     pointCircle.setOutlineThickness(1.0f);
+
+    saveFilenameBuffer.fill(0);
 }
 
 Tri::State::~State() {
@@ -49,6 +52,7 @@ void Tri::State::handle_events() {
             window.close();
             flags.reset(1);
         } else if(event.type == sf::Event::KeyPressed) {
+            if(!flags.test(6)) {
                 if(event.key.code == sf::Keyboard::H) {
                     flags.flip(0);
                 } else if(event.key.code == sf::Keyboard::U) {
@@ -100,9 +104,12 @@ void Tri::State::handle_events() {
                     flags.flip(2);
                 } else if(event.key.code == sf::Keyboard::B) {
                     flags.flip(5);
+                } else if(event.key.code == sf::Keyboard::S) {
+                    flags.flip(6);
+                }
             }
         } else if(event.type == sf::Event::MouseButtonPressed) {
-            if(!flags.test(2) && !flags.test(5)) {
+            if(!flags.test(2) && !flags.test(5) && !flags.test(6)) {
                 switch(currentTri_state) {
                 case CurrentState::NONE:
                     currentTri[0] = sf::Vector2f(event.mouseButton.x, event.mouseButton.y);
@@ -170,24 +177,14 @@ void Tri::State::update() {
     Tri::draw_show_help(this);
     Tri::draw_color_picker(this);
     Tri::draw_bg_color_picker(this);
+    Tri::draw_save(this);
     Tri::draw_help(this);
 
     ImGui::EndFrame();
 }
 
 void Tri::State::draw() {
-    window.clear(bgColor);
-
-    // draw tris
-    for(unsigned int i = 0; i < trisIndex; ++i) {
-        window.draw(tris[i]);
-    }
-
-    // draw points
-    for(unsigned int i = 0; i < currentTri_state; ++i) {
-        pointCircle.setPosition(currentTri[i]);
-        window.draw(pointCircle);
-    }
+    draw_to_target(&window);
 
     // draw gui stuff
     ImGui::SFML::Render(window);
@@ -195,6 +192,23 @@ void Tri::State::draw() {
     window.display();
 }
 
+void Tri::State::draw_to_target(sf::RenderTarget *target, bool draw_points) {
+    target->clear(bgColor);
+
+    // draw tris
+    for(unsigned int i = 0; i < trisIndex; ++i) {
+        target->draw(tris[i]);
+    }
+
+    // draw points
+    if(draw_points) {
+        for(unsigned int i = 0; i < currentTri_state; ++i) {
+            pointCircle.setPosition(currentTri[i]);
+            target->draw(pointCircle);
+        }
+    }
+}
+
 unsigned int Tri::State::get_width() const {
     return width;
 }
@@ -220,3 +234,45 @@ float* Tri::State::get_bg_color() {
     flags.set(4);
     return bgColorPickerColor;
 }
+
+Tri::State::FilenameBufferType* Tri::State::get_save_filename_buffer() {
+    return &saveFilenameBuffer;
+}
+
+bool Tri::State::do_save() {
+    sf::RenderTexture saveTexture;
+    if(!saveTexture.create(width, height)) {
+#ifndef NDEBUG
+        puts("ERROR: Failed to create texture for saving");
+#endif
+        failedSaveMessage = std::string("Failed to create texture for saving");
+        return false;
+    }
+
+    draw_to_target(&saveTexture, false);
+    saveTexture.display();
+
+    sf::Image saveImage = saveTexture.getTexture().copyToImage();
+    std::string filename = std::string(saveFilenameBuffer.data());
+    if(saveImage.saveToFile(filename)) {
+#ifndef NDEBUG
+        printf("Saved to \"%s\"\n", filename.c_str());
+#endif
+        failedSaveMessage.clear();
+        return true;
+    } else {
+#ifndef NDEBUG
+        printf("ERROR: Failed to save \"%s\"\n", filename.c_str());
+#endif
+        failedSaveMessage = std::string("Failed to save (does the name end in \".png\"?)");
+        return false;
+    }
+}
+
+std::string_view Tri::State::failed_save_message() const {
+    return failedSaveMessage;
+}
+
+void Tri::State::close_save() {
+    flags.reset(6);
+}

src/state.hpp

@@ -3,6 +3,7 @@
 
 #include <bitset>
 #include <vector>
+#include <array>
 
 #include <SFML/System.hpp>
 #include <SFML/Graphics.hpp>
@@ -22,6 +23,7 @@ namespace Tri {
          * 3 - color picker color dirty
          * 4 - bg color picker color dirty
          * 5 - display bg color picker
+         * 6 - draw save
          */
         typedef std::bitset<64> BitsetType;
         BitsetType flags;
@@ -44,11 +46,19 @@ namespace Tri {
         float bgColorPickerColor[3];
         sf::Color bgColor;
 
+        typedef std::array<char, 256> FilenameBufferType;
+        FilenameBufferType saveFilenameBuffer;
+        std::string failedSaveMessage;
+
     public:
         void handle_events();
         void update();
         void draw();
 
+    private:
+        void draw_to_target(sf::RenderTarget *target, bool draw_points = true);
+
+    public:
         unsigned int get_width() const;
         unsigned int get_height() const;
 
@@ -58,6 +68,11 @@ namespace Tri {
 
         float* get_color();
         float* get_bg_color();
+
+        FilenameBufferType* get_save_filename_buffer();
+        bool do_save();
+        std::string_view failed_save_message() const;
+        void close_save();
     };
 }