Add support for cubemaps and skybox (#72)

* Add support for cubemaps and skybox

Currently not set up to be used in a Scene: will need external resources first.

* Add editor::FileBrowser

- Rename `BrowseGltf` to `FileBrowser`.
- Incorporate "*.skybox" into browsers and drops.
- Use `string_view` for events.

* Add operator""_B, FixedBitmap

- Use `u` instead of `U` for unsigned literals.

* Integrate Skybox and enable async loads

- Remove increment logic from `MaybeFuture` and expose class in thread_pool.hpp.
- Add `LoadFuture` with increment logic to gltf_loader.hpp.

* Add zip_ranges

- Use `zip_ranges()` instead of `enumerate()` for loading skybox data.
- Remove enumerate.hpp from TUs where it's unused.

Author: karnkaul

CMakeLists.txt

@@ -37,15 +37,18 @@ if(FACADE_BUILD_EXE AND FACADE_BUILD_SHADERS)
     ${CMAKE_CURRENT_SOURCE_DIR}/src/shaders/default.vert
     ${CMAKE_CURRENT_SOURCE_DIR}/src/shaders/unlit.frag
     ${CMAKE_CURRENT_SOURCE_DIR}/src/shaders/lit.frag
+    ${CMAKE_CURRENT_SOURCE_DIR}/src/shaders/skybox.frag
 
     OUTPUT
     ${CMAKE_CURRENT_SOURCE_DIR}/src/bin/default_vert.spv.hpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/bin/unlit_frag.spv.hpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/bin/lit_frag.spv.hpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/src/bin/skybox_frag.spv.hpp
 
     COMMAND embed-shader ${CMAKE_CURRENT_SOURCE_DIR}/src/shaders/default.vert > ${CMAKE_CURRENT_SOURCE_DIR}/src/bin/default_vert.spv.hpp
     COMMAND embed-shader ${CMAKE_CURRENT_SOURCE_DIR}/src/shaders/unlit.frag > ${CMAKE_CURRENT_SOURCE_DIR}/src/bin/unlit_frag.spv.hpp
     COMMAND embed-shader ${CMAKE_CURRENT_SOURCE_DIR}/src/shaders/lit.frag > ${CMAKE_CURRENT_SOURCE_DIR}/src/bin/lit_frag.spv.hpp
+    COMMAND embed-shader ${CMAKE_CURRENT_SOURCE_DIR}/src/shaders/skybox.frag > ${CMAKE_CURRENT_SOURCE_DIR}/src/bin/skybox_frag.spv.hpp
   )
 endif()
 

lib/engine/CMakeLists.txt

@@ -43,6 +43,7 @@ target_sources(${PROJECT_NAME} PRIVATE
   include/${target_prefix}/engine/editor/browse_file.hpp
   include/${target_prefix}/engine/editor/common.hpp
   include/${target_prefix}/engine/editor/drag_drop_id.hpp
+  include/${target_prefix}/engine/editor/file_browser.hpp
   include/${target_prefix}/engine/editor/inspector.hpp
   include/${target_prefix}/engine/editor/log.hpp
   include/${target_prefix}/engine/editor/reflector.hpp
@@ -54,6 +55,7 @@ target_sources(${PROJECT_NAME} PRIVATE
 
   src/editor/browse_file.cpp
   src/editor/common.cpp
+  src/editor/file_browser.cpp
   src/editor/inspector.cpp
   src/editor/log.cpp
   src/editor/reflector.cpp

lib/engine/include/facade/engine/editor/file_browser.hpp

@@ -0,0 +1,31 @@
+#pragma once
+#include <facade/engine/editor/browse_file.hpp>
+
+namespace facade::editor {
+///
+/// \brief Persistent modal pop up to browse for a file given a list of extensions.
+///
+/// Uses Modal and BrowseFile.
+///
+class FileBrowser {
+  public:
+	struct Result {
+		std::string selected{};
+		std::string_view browse_path{};
+		bool path_changed{};
+	};
+
+	FileBrowser(std::string label, std::vector<std::string> extensions, std::string browse_path);
+
+	Result update(bool& out_trigger);
+
+	std::vector<std::string> extensions;
+
+  private:
+	std::string m_browse_path;
+	std::string m_label;
+	std::vector<std::string_view> m_extensions_view{};
+	env::DirEntries m_dir_entries{};
+	bool m_trigger{};
+};
+} // namespace facade::editor

lib/engine/include/facade/engine/engine.hpp

@@ -83,11 +83,11 @@ class Engine {
 	void request_stop();
 
 	///
-	/// \brief Load a GLTF scene asynchronously.
+	/// \brief Load a GLTF scene / Skybox asynchronously.
 	///
 	/// Subsequent requests will be rejected if one is in flight
 	///
-	bool load_async(std::string gltf_json_path, UniqueTask<void()> on_loaded = {});
+	bool load_async(std::string json_path, UniqueTask<void()> on_loaded = {});
 	///
 	/// \brief Obtain status of in-flight async load request (if active).
 	///

lib/engine/include/facade/engine/scene_renderer.hpp

@@ -4,18 +4,21 @@
 #include <facade/vk/buffer.hpp>
 
 namespace facade {
+class Skybox;
+
 class SceneRenderer {
   public:
 	explicit SceneRenderer(Gfx const& gfx);
 
-	void render(Scene const& scene, Renderer& renderer, vk::CommandBuffer cb);
+	void render(Scene const& scene, Ptr<Skybox const> skybox, Renderer& renderer, vk::CommandBuffer cb);
 
   private:
 	void write_view(glm::vec2 const extent);
 	void update_view(Pipeline& out_pipeline) const;
-	std::span<glm::mat4x4 const> make_instances(Node const& node, glm::mat4x4 const& parent);
+	std::span<glm::mat4x4 const> make_instances(Node const& node, glm::mat4x4 const& parent) const;
 
-	void render(Renderer& renderer, vk::CommandBuffer cb, Node const& node, glm::mat4 const& parent = matrix_identity_v);
+	void render(Renderer& renderer, vk::CommandBuffer cb, Skybox const& skybox) const;
+	void render(Renderer& renderer, vk::CommandBuffer cb, Node const& node, glm::mat4 const& parent = matrix_identity_v) const;
 
 	Gfx m_gfx;
 	Sampler m_sampler;
@@ -24,7 +27,7 @@ class SceneRenderer {
 	Texture m_white;
 	Texture m_black;
 
-	std::vector<glm::mat4x4> m_instance_mats{};
+	mutable std::vector<glm::mat4x4> m_instance_mats{};
 	Scene const* m_scene{};
 };
 } // namespace facade

lib/engine/src/editor/browse_file.cpp

@@ -2,6 +2,7 @@
 #include <imgui.h>
 #include <facade/engine/editor/browse_file.hpp>
 #include <facade/util/env.hpp>
+#include <facade/util/fixed_string.hpp>
 #include <filesystem>
 
 namespace facade::editor {
@@ -75,6 +76,16 @@ auto BrowseFile::operator()(NotClosed<Popup> popup, std::string& out_path) -> Re
 		if (ImGui::Button("Downloads")) { cd(std::move(downloads)); }
 	}
 
+	ImGui::Separator();
+	auto exts = FixedString{};
+	if (extensions.empty()) {
+		exts = "*.*";
+	} else {
+		exts = FixedString{"*{}", extensions[0]};
+		for (auto it = std::next(extensions.begin()); it != extensions.end(); ++it) { exts += FixedString{", *{}", *it}; }
+	}
+	ImGui::Text("%s", exts.c_str());
+
 	ImGui::Separator();
 	if (auto window = editor::Window{popup, "File Tree"}) {
 		env::GetDirEntries{.extensions = extensions}(out_entries, out_path.c_str());

lib/engine/src/editor/file_browser.cpp

@@ -0,0 +1,29 @@
+#include <imgui.h>
+#include <facade/engine/editor/file_browser.hpp>
+
+namespace facade::editor {
+FileBrowser::FileBrowser(std::string label, std::vector<std::string> extensions, std::string browse_path)
+	: extensions(std::move(extensions)), m_browse_path(std::move(browse_path)), m_label(std::move(label)) {
+	if (m_label.empty()) { m_label = "Browse..."; }
+}
+
+auto FileBrowser::update(bool& out_trigger) -> Result {
+	auto ret = Result{};
+	if (out_trigger && !ImGui::IsPopupOpen(m_label.c_str())) { Modal::open(m_label.c_str()); }
+	out_trigger = false;
+	if (ImGui::IsPopupOpen(m_label.c_str())) { ImGui::SetNextWindowSize({400.0f, 250.0f}, ImGuiCond_FirstUseEver); }
+	if (auto popup = Modal{m_label.c_str()}) {
+		m_extensions_view.clear();
+		m_extensions_view.reserve(extensions.size());
+		for (auto const& extension : extensions) { m_extensions_view.push_back(extension); }
+		auto [selected, changed] = BrowseFile{.out_entries = m_dir_entries, .extensions = m_extensions_view}(popup, m_browse_path);
+		ret.path_changed = changed;
+		ret.browse_path = m_browse_path;
+		if (!selected.empty()) {
+			popup.close_current();
+			ret.selected = std::move(selected);
+		}
+	}
+	return ret;
+}
+} // namespace facade::editor

lib/engine/src/editor/reflector.cpp

@@ -1,6 +1,5 @@
 #include <imgui.h>
 #include <facade/engine/editor/reflector.hpp>
-#include <facade/util/enumerate.hpp>
 #include <facade/util/fixed_string.hpp>
 #include <optional>