gui: Background image option in Game Select screen (#460)

* gui: add background images

* gui: add background alpha channel

* gui: replace background texture with GLObject

.gitmodules

@@ -27,6 +27,9 @@
 	path = src/external/spdlog
 	url = https://github.com/gabime/spdlog.git
 	branch = v1.x
+[submodule "src/external/stb"]
+	path = src/external/stb
+	url = https://github.com/nothings/stb
 [submodule "src/external/dirent"]
 	path = src/external/dirent
 	url = https://github.com/tronkko/dirent

src/emulator/config.cpp

@@ -100,6 +100,8 @@ bool serialize(Config &cfg) {
     config_file_emit_optional_single(emitter, "log-level", cfg.log_level);
     config_file_emit_optional_single(emitter, "pref-path", cfg.pref_path);
     config_file_emit_optional_single(emitter, "wait-for-debugger", cfg.wait_for_debugger);
+    config_file_emit_optional_single(emitter, "background-image", cfg.background_image);
+    config_file_emit_optional_single(emitter, "background-alpha", cfg.background_alpha);
 
     emitter << YAML::EndMap;
 
@@ -118,7 +120,7 @@ static bool deserialize(Config &cfg) {
     try {
         config_node = YAML::LoadFile("config.yml");
     } catch (YAML::Exception &exception) {
-        std::cerr << "Config file can't be load: Error: " << exception.what() << "\n";
+        std::cerr << "Config file can't be loaded: Error: " << exception.what() << "\n";
         return false;
     }
 
@@ -132,6 +134,8 @@ static bool deserialize(Config &cfg) {
     get_yaml_value_optional(config_node, "log-level", &cfg.log_level, static_cast<int>(spdlog::level::trace));
     get_yaml_value_optional(config_node, "pref-path", &cfg.pref_path);
     get_yaml_value_optional(config_node, "wait-for-debugger", &cfg.wait_for_debugger);
+    get_yaml_value_optional(config_node, "background-image", &cfg.background_image);
+    get_yaml_value_optional(config_node, "background-alpha", &cfg.background_alpha);
 
     // lle-modules
     try {

src/emulator/glutil/include/glutil/object.h

@@ -24,20 +24,25 @@
 
 class GLObject {
 public:
-    using Deleter = std::function<void(GLuint)>;
+    using SingularDeleter = std::function<void(GLuint)>;
+    using AggregateDeleter = std::function<void(int, const GLuint *)>;
 
     GLObject() = default;
     ~GLObject();
 
-    bool init(GLuint name, Deleter deleter);
+    bool init(GLuint name, AggregateDeleter aggregate_deleter);
+    bool init(GLuint name, SingularDeleter singular_deleter);
     GLuint get() const;
     operator GLuint() const;
+    operator bool() const;
 
 private:
+    bool init(GLuint name);
     const GLObject &operator=(const GLObject &) = delete;
 
     GLuint name = 0;
-    Deleter deleter = nullptr;
+    AggregateDeleter aggregate_deleter = nullptr;
+    SingularDeleter singular_deleter = nullptr;
 };
 
 using SharedGLObject = std::shared_ptr<GLObject>;

src/emulator/glutil/src/object.cpp

@@ -20,22 +20,37 @@
 #include <cassert>
 
 GLObject::~GLObject() {
-    if (deleter != nullptr) {
-        deleter(name);
+    if (aggregate_deleter != nullptr) {
+        aggregate_deleter(1, &name);
+    }
+    if (singular_deleter != nullptr) {
+        singular_deleter(name);
     }
     name = 0;
 }
 
-bool GLObject::init(GLuint name, Deleter deleter) {
+bool GLObject::init(GLuint name) {
     assert(name != 0);
     assert(this->name == 0);
     this->name = name;
-    if (deleter)
-        this->deleter = deleter;
 
     return name != 0;
 }
 
+bool GLObject::init(GLuint name, AggregateDeleter aggregate_deleter) {
+    if (aggregate_deleter)
+        this->aggregate_deleter = aggregate_deleter;
+
+    return init(name);
+}
+
+bool GLObject::init(GLuint name, SingularDeleter singular_deleter) {
+    if (singular_deleter)
+        this->singular_deleter = singular_deleter;
+
+    return init(name);
+}
+
 GLuint GLObject::get() const {
     assert(name != 0);
     return name;
@@ -45,3 +60,7 @@ GLObject::operator GLuint() const {
     assert(name != 0);
     return name;
 }
+
+GLObject::operator bool() const {
+    return name;
+}

src/emulator/gui/CMakeLists.txt

@@ -23,4 +23,4 @@ src/about_dialog.cpp
 )
 
 target_include_directories(gui PUBLIC include)
-target_link_libraries(gui PUBLIC sdl2 imgui glutil host kernel cpu util dialog)
+target_link_libraries(gui PUBLIC sdl2 stb imgui glutil host kernel cpu util dialog)

src/emulator/gui/include/gui/state.h

@@ -22,6 +22,8 @@
 #include <imgui.h>
 #include <imgui_memory_editor.h>
 
+#include <glutil/object.h>
+
 namespace gui {
 
 enum SelectorState {
@@ -90,6 +92,8 @@ struct State {
     char disassembly_count[5] = "100";
     std::vector<std::string> disassembly;
 
+    GLObject background_texture;
+
     SceUID thread_watch_index = -1;
 
     // imgui

src/emulator/gui/src/game_selector.cpp

@@ -33,10 +33,17 @@ void draw_game_selector(HostState &host) {
 
     ImGui::SetNextWindowPos(ImVec2(0, MENUBAR_HEIGHT), ImGuiSetCond_Always);
     ImGui::SetNextWindowSize(ImVec2(display_size.x, display_size.y - MENUBAR_HEIGHT), ImGuiSetCond_Always);
+    if (host.cfg.background_alpha)
+        ImGui::SetNextWindowBgAlpha(host.cfg.background_alpha.value());
     ImGui::Begin("Game Selector", nullptr, ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoBringToFrontOnFocus | ImGuiWindowFlags_NoSavedSettings);
 
     static ImGuiTextFilter search_bar;
 
+    if (host.gui.background_texture) {
+        ImGui::GetBackgroundDrawList()->AddImage(reinterpret_cast<void *>(host.gui.background_texture.get()),
+            ImVec2(0, 0), display_size);
+    }
+
     switch (host.gui.game_selector.state) {
     case SELECT_APP:
         ImGui::Columns(3);

src/emulator/gui/src/gui.cpp

@@ -29,6 +29,9 @@
 
 #include <SDL_video.h>
 
+#define STB_IMAGE_IMPLEMENTATION
+#include <stb_image.h>
+
 #include <fstream>
 #include <string>
 
@@ -120,12 +123,43 @@ static void init_font(State &gui) {
     gui.normal_font = io.Fonts->AddFontFromMemoryTTF(gui.font_data.data(), font_file_size, 16, &font_config, io.Fonts->GetGlyphRangesJapanese());
 }
 
+static void init_background(State &gui, const std::string &image_path) {
+    if (!std::ifstream(image_path).good()) {
+        LOG_INFO("Invalid background file path {}.", image_path);
+        return;
+    }
+
+    int32_t width = 0;
+    int32_t height = 0;
+    stbi_uc *data = stbi_load(image_path.c_str(), &width, &height, nullptr, STBI_rgb_alpha);
+
+    if (!data) {
+        LOG_INFO("Could not load background from {}.", image_path);
+        return;
+    }
+
+    GLuint texture;
+    glGenTextures(1, &texture);
+    gui.background_texture.init(texture, glDeleteTextures);
+
+    glBindTexture(GL_TEXTURE_2D, gui.background_texture.get());
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_R, GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+}
+
 void init(HostState &host) {
     ImGui::CreateContext();
     ImGui_ImplSdlGL3_Init(host.window.get());
 
     init_style();
     init_font(host.gui);
+    if (host.cfg.background_image) {
+        init_background(host.gui, host.cfg.background_image.value());
+    }
 }
 
 void draw_begin(HostState &host) {

src/emulator/host/include/host/config.h

@@ -40,4 +40,6 @@ struct Config {
     optional<std::string> pref_path;
     bool archive_log = false;
     optional<bool> wait_for_debugger;
+    optional<std::string> background_image;
+    optional<float> background_alpha;
 };

src/external/CMakeLists.txt

@@ -54,6 +54,9 @@ target_include_directories(elfio INTERFACE "${CMAKE_CURRENT_SOURCE_DIR}/elfio")
 add_subdirectory(spdlog EXCLUDE_FROM_ALL)
 target_compile_definitions(spdlog INTERFACE SPDLOG_WCHAR_FILENAMES=1 SPDLOG_NO_THREAD_ID=1 SPDLOG_ACTIVE_LEVEL=SPDLOG_LEVEL_TRACE)
 
+add_library(stb INTERFACE)
+target_include_directories(stb INTERFACE "${CMAKE_CURRENT_SOURCE_DIR}/stb")
+
 option(BUILD_SHARED_LIBS "Build shared instead of static libraries." OFF)
 option(OPTION_BUILD_TOOLS "Build tools." OFF)
 option(OPTION_BUILD_EXAMPLES "Build examples." OFF)