OpenRA3 v0.0.1: C++26 modules, BIG4/RefPack reader, minimal skirmish

src/client/ra3.client.cppm

@@ -0,0 +1,74 @@
+module;
+
+#include <cstdint>
+#include <memory>
+#include <string_view>
+
+export module ra3.client;
+
+import ra3.core;
+import ra3.logic;
+
+/**
+ * The presentation layer: an abstract output surface plus the client facade
+ * that owns the simulation and drives the frame loop.
+ *
+ * A future W3D/D3D9 backend implements the same `display` interface; the
+ * default headless backend keeps OpenRA3 runnable on a CPU-only box.
+ */
+export namespace ra3::client {
+    using ra3::core::uint32;
+
+    /**
+     * Abstract output surface presented once per logic frame.
+     */
+    class display {
+    public:
+        virtual ~display() = default;
+
+        virtual auto begin_frame() -> void = 0;
+        virtual auto end_frame() -> void = 0;
+        [[nodiscard]] virtual auto name() const -> std::string_view = 0;
+    };
+
+    /**
+     * A display that renders nothing and consumes no resources.
+     */
+    class headless_display final : public display {
+    public:
+        auto begin_frame() -> void override {}
+        auto end_frame() -> void override {}
+        [[nodiscard]] auto name() const -> std::string_view override { return "headless"; }
+    };
+
+    /**
+     * Owns the simulation and its display, and drives the frame loop.
+     */
+    class game_client {
+    public:
+        game_client() = default;
+
+        [[nodiscard]] auto logic() -> logic::game_logic & { return logic_; }
+        [[nodiscard]] auto display() -> client::display & { return *display_; }
+
+        auto set_display(std::unique_ptr<client::display> value) -> void { display_ = std::move(value); }
+
+        /**
+         * Run `frames` logic steps, bracketing each with a present.
+         *
+         * @param target Simulation to advance.
+         * @param frames Number of 30 Hz logic frames to run.
+         */
+        auto run(logic::game_logic &target, uint32 frames) -> void {
+            for (uint32 i = 0; i < frames; ++i) {
+                display_->begin_frame();
+                target.update();
+                display_->end_frame();
+            }
+        }
+
+    private:
+        logic::game_logic logic_;
+        std::unique_ptr<client::display> display_ = std::make_unique<headless_display>();
+    };
+}