[nostaliga/core] Add Drawer system and make ImGui use configurable

src/nostalgia/core/config.hpp

@@ -8,12 +8,25 @@
 
 #pragma once
 
+#if __has_include(<imgui.h>)
+#define IMGUI_IMPL_OPENGL_ES3
+#include <imgui_impl_opengl3.h>
+#include <imgui_impl_glfw.h>
+#endif
+
 #include <ox/std/types.hpp>
 
 namespace nostalgia::core {
 
 namespace config {
 
+constexpr auto ImGuiEnabled =
+#if __has_include(<imgui.h>)
+true;
+#else
+false;
+#endif
+
 enum class SdlVsync {
 	Adaptive = -1,
 	Off = 0,

src/nostalgia/core/context.hpp

@@ -12,10 +12,19 @@
 
 namespace nostalgia::core {
 
+class Context;
+
+class Drawer {
+	public:
+		virtual ~Drawer() = default;
+		virtual void draw(Context*) noexcept = 0;
+};
+
 // User Input Output
 class Context {
 	public:
 		ox::FileSystem *rom = nullptr;
+		ox::Vector<Drawer*, 5> drawer;
 	private:
 		void *m_windowerData = nullptr;
 		void *m_rendererData = nullptr;

src/nostalgia/core/gfx.cpp

@@ -141,6 +141,19 @@ char charMap[128] = {
 	0,  // ~
 };
 
+void addCustomDrawer(Context *ctx, Drawer *cd) noexcept {
+	ctx->drawer.emplace_back(cd);
+}
+
+void removeCustomDrawer(Context *ctx, Drawer *cd) noexcept {
+	for (auto i = 0u; i < ctx->drawer.size(); ++i) {
+		if (ctx->drawer[i] == cd) {
+			oxIgnoreError(ctx->drawer.erase(i));
+			break;
+		}
+	}
+}
+
 void setSprite(Context *c, const Sprite &s) noexcept {
 	setSprite(c, s.idx, s.x, s.y, s.tileIdx, s.spriteShape, s.spriteSize, s.flipX);
 }

src/nostalgia/core/gfx.hpp

@@ -76,6 +76,10 @@ ox::Error initGfx(Context *ctx) noexcept;
 
 ox::Error shutdownGfx(Context *ctx) noexcept;
 
+void addCustomDrawer(Context *ctx, Drawer *cd) noexcept;
+
+void removeCustomDrawer(Context *ctx, Drawer *cd) noexcept;
+
 [[nodiscard]]
 int getScreenWidth(Context *ctx) noexcept;
 

src/nostalgia/core/glfw/gfx.cpp

@@ -7,9 +7,8 @@
  */
 
 #include <GLFW/glfw3.h>
-#include <imgui.h>
-#include <imgui_impl_glfw.h>
 
+#include <nostalgia/core/config.hpp>
 #include <nostalgia/core/userland/gfx.hpp>
 
 #include "core.hpp"
@@ -38,14 +37,15 @@ ox::Error initGfx(Context *ctx) noexcept {
 	}
 	glfwSetWindowUserPointer(id->window, ctx);
 	glfwMakeContextCurrent(id->window);
-	IMGUI_CHECKVERSION();
-	ImGui::CreateContext();
-	auto &io = ImGui::GetIO();
-	io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
-	io.MouseDrawCursor = true;
-	ImGui_ImplGlfw_InitForOpenGL(id->window, true);
-	oxReturnError(renderer::init(ctx));
-	return OxError(0);
+	if constexpr(config::ImGuiEnabled) {
+		IMGUI_CHECKVERSION();
+		ImGui::CreateContext();
+		auto &io = ImGui::GetIO();
+		io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
+		io.MouseDrawCursor = true;
+		ImGui_ImplGlfw_InitForOpenGL(id->window, true);
+	}
+	return renderer::init(ctx);
 }
 
 ox::Error shutdownGfx(Context *ctx) noexcept {

src/nostalgia/core/userland/gfx_opengl.cpp

@@ -10,10 +10,6 @@
 
 #include <nostalgia/glutils/glutils.hpp>
 
-#define IMGUI_IMPL_OPENGL_ES3
-#include <imgui_impl_opengl3.h>
-#include <imgui_impl_glfw.h>
-
 #include <ox/std/bit.hpp>
 #include <ox/std/fmt.hpp>
 
@@ -232,7 +228,7 @@ ox::Error shutdown(Context *ctx) noexcept {
 
 ox::Error loadBgTexture(Context *ctx, int section, void *pixels, int w, int h) noexcept {
 	oxTracef("nostalgia::core::gfx::gl", "loadBgTexture: { section: {}, w: {}, h: {} }", section, w, h);
-	const auto &id = ctx->rendererData<GlImplData>();
+	const auto id = ctx->rendererData<GlImplData>();
 	auto &tex = id->backgrounds[static_cast<std::size_t>(section)].tex;
 	tex = loadTexture(w, h, pixels);
 	return OxError(0);
@@ -241,7 +237,7 @@ ox::Error loadBgTexture(Context *ctx, int section, void *pixels, int w, int h) n
 }
 
 uint8_t bgStatus(Context *ctx) noexcept {
-	const auto &id = ctx->rendererData<renderer::GlImplData>();
+	const auto id = ctx->rendererData<renderer::GlImplData>();
 	uint8_t out = 0;
 	for (unsigned i = 0; i < id->backgrounds.size(); ++i) {
 		out |= id->backgrounds[i].enabled << i;
@@ -250,19 +246,19 @@ uint8_t bgStatus(Context *ctx) noexcept {
 }
 
 void setBgStatus(Context *ctx, uint32_t status) noexcept {
-	const auto &id = ctx->rendererData<renderer::GlImplData>();
+	const auto id = ctx->rendererData<renderer::GlImplData>();
 	for (unsigned i = 0; i < id->backgrounds.size(); ++i) {
 		id->backgrounds[i].enabled = (status >> i) & 1;
 	}
 }
 
 bool bgStatus(Context *ctx, unsigned bg) noexcept {
-	const auto &id = ctx->rendererData<renderer::GlImplData>();
+	const auto id = ctx->rendererData<renderer::GlImplData>();
 	return id->backgrounds[bg].enabled;
 }
 
 void setBgStatus(Context *ctx, unsigned bg, bool status) noexcept {
-	const auto &id = ctx->rendererData<renderer::GlImplData>();
+	const auto id = ctx->rendererData<renderer::GlImplData>();
 	id->backgrounds[bg].enabled = status;
 }
 
@@ -272,16 +268,23 @@ void draw(Context *ctx) noexcept {
 	renderer::tickFps(id);
 	ImGui_ImplOpenGL3_NewFrame();
 	ImGui_ImplGlfw_NewFrame();
-	ImGui::NewFrame();
+	if constexpr(config::ImGuiEnabled) {
+		ImGui::NewFrame();
+	}
 	// clear screen
 	glClearColor(0, 0, 0, 1);
 	glClear(GL_COLOR_BUFFER_BIT);
 	// render
+	renderer::drawBackgrounds(id);
 	//bool showDemo = true;
 	//ImGui::ShowDemoWindow(&showDemo);
-	renderer::drawBackgrounds(id);
-	ImGui::Render();
-	ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+	for (const auto cd : ctx->drawer) {
+		cd->draw(ctx);
+	}
+	if constexpr(config::ImGuiEnabled) {
+		ImGui::Render();
+		ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+	}
 }
 
 void clearTileLayer(Context *ctx, int layer) noexcept {