Replace query_array with a more useful query_poll

libs/gfx/include/psemek/gfx/query.hpp

@@ -1,86 +1,33 @@
 #pragma once
 
 #include <psemek/gfx/gl.hpp>
+#include <psemek/util/function.hpp>
 
 #include <vector>
 
 namespace psemek::gfx
 {
 
-	struct query_array
+	struct query_pool
 	{
-		query_array() = default;
-		query_array(std::size_t size);
-		~query_array();
+		struct scope
+		{
+			GLenum target;
+
+			~scope();
+		};
+
+		scope begin(GLenum target, util::function<void(GLint)> callback);
+
+		void poll();
 
 		std::size_t size() const { return ids_.size(); }
 
-		void resize(std::size_t size);
-
-		GLuint operator[](std::size_t i) const;
-
-		struct [[maybe_unused]] query_scope
-		{
-			GLenum type;
-
-			query_scope(GLenum type)
-				: type{type}
-			{}
-
-			query_scope(query_scope const &) = delete;
-			query_scope(query_scope &&) = delete;
-
-			query_scope & operator = (query_scope const &) = delete;
-			query_scope & operator = (query_scope &&) = delete;
-
-			~query_scope()
-			{
-				gl::EndQuery(type);
-			}
-		};
-
-		query_scope begin(std::size_t i, GLenum type) const;
+		~query_pool();
 
 	private:
 		std::vector<GLuint> ids_;
+		std::vector<util::function<void(GLint)>> callbacks_;
 	};
 
-	inline query_array::query_array(std::size_t size)
-		: ids_(size)
-	{
-		gl::GenQueries(size, ids_.data());
-	}
-
-	inline query_array::~query_array()
-	{
-		gl::DeleteQueries(ids_.size(), ids_.data());
-		ids_.clear();
-	}
-
-	inline void query_array::resize(std::size_t size)
-	{
-		if (size < ids_.size())
-		{
-			gl::DeleteQueries(ids_.size() - size, ids_.data() + size);
-			ids_.resize(size);
-		}
-		else if (size > ids_.size())
-		{
-			std::size_t old_size = ids_.size();
-			ids_.resize(size);
-			gl::GenQueries(size - old_size, ids_.data() + old_size);
-		}
-	}
-
-	inline GLuint query_array::operator[](std::size_t i) const
-	{
-		return ids_[i];
-	}
-
-	inline query_array::query_scope query_array::begin(std::size_t i, GLenum type) const
-	{
-		gl::BeginQuery(type, ids_[i]);
-		return query_scope{type};
-	}
-
 }

libs/gfx/source/query.cpp

@@ -0,0 +1,58 @@
+#include <psemek/gfx/query.hpp>
+
+#include <optional>
+
+namespace psemek::gfx
+{
+
+	query_pool::scope::~scope()
+	{
+		gl::EndQuery(target);
+	}
+
+	query_pool::scope query_pool::begin(GLenum target, util::function<void(GLint)> callback)
+	{
+		std::optional<std::size_t> index;
+		for (std::size_t i = 0; i < ids_.size(); ++i)
+		{
+			if (callbacks_[i]) continue;
+			index = i;
+			break;
+		}
+
+		if (!index)
+		{
+			index = ids_.size();
+			gl::GenQueries(1, &ids_.emplace_back());
+			callbacks_.emplace_back();
+		}
+
+		callbacks_[*index] = std::move(callback);
+		gl::BeginQuery(target, ids_[*index]);
+
+		return {target};
+	}
+
+	void query_pool::poll()
+	{
+		for (std::size_t i = 0; i < ids_.size(); ++i)
+		{
+			if (!callbacks_[i]) continue;
+
+			GLint result;
+			gl::GetQueryObjectiv(ids_[i], gl::QUERY_RESULT_AVAILABLE, &result);
+			if (result == gl::TRUE)
+			{
+				gl::GetQueryObjectiv(ids_[i], gl::QUERY_RESULT, &result);
+				callbacks_[i](result);
+				callbacks_[i].reset();
+			}
+		}
+	}
+
+	query_pool::~query_pool()
+	{
+		gl::DeleteQueries(ids_.size(), ids_.data());
+	}
+
+}