Initial commit: testpattern → fakesink pipeline over MXL shared memory

- NodeBase, Signal, FlowDef, V210 shared headers - testpattern node: SMPTE 75% color bars writer at 25fps - fakesink node: non-blocking MXL reader with per-second stats - studio-manager: FlowGraph data model, graph-driven fork/exec launcher - mxl pinned as submodule at 0ae1dc5 Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-06-23 13:35:01 +03:00
commit ca682eaf0a
17 changed files with 1269 additions and 0 deletions
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+#pragma once
+
+#include <string>
+#include <vector>
+#include <nlohmann/json.hpp>
+
+namespace dmf {
+
+// A node instance in the pipeline graph.
+struct NodeDef {
+    std::string    id;     // unique instance id; becomes node_id in NODE_CONFIG
+    std::string    type;   // binary suffix: "testpattern" → "dmf-node-testpattern"
+    nlohmann::json params; // node-specific config (width, height, fps_num, ...)
+};
+
+// A directed edge between two nodes, carried by one MXL flow.
+//
+// from_port / to_port are the NODE_CONFIG keys each end receives the flow descriptor under.
+// The injected value is a JSON object: { "id": "<uuid>", ...format fields }.
+// Nodes read the UUID as cfg["flow_id"]["id"] and format fields as cfg["flow_id"]["fps_num"] etc.
+//
+// format examples:
+//   video: { "kind":"video", "width":1920, "height":1080, "fps_num":25, "fps_den":1 }
+//   audio: { "kind":"audio", "sample_rate":48000, "channels":2, "bit_depth":24 }
+//
+// PiP sink example: two edges with to_port "input_a_flow_id" and "input_b_flow_id".
+struct FlowEdge {
+    std::string    id;        // UUID for the MXL flow (set by build_graph)
+    std::string    from_node;
+    std::string    from_port; // key injected into source's NODE_CONFIG
+    std::string    to_node;
+    std::string    to_port;   // key injected into sink's NODE_CONFIG
+    nlohmann::json format;    // flow format metadata (kind, width, height, fps_num, ...)
+};
+
+// The complete pipeline description.
+struct FlowGraph {
+    std::vector<NodeDef>  nodes;
+    std::vector<FlowEdge> edges;
+
+    // Returns the full NODE_CONFIG JSON for one node.
+    // Each connected edge injects a flow descriptor object under the port key:
+    //   cfg[port] = { "id": "<uuid>", ...format fields }
+    nlohmann::json node_config(const std::string& node_id) const {
+        const NodeDef* nd = nullptr;
+        for (const auto& n : nodes)
+            if (n.id == node_id) { nd = &n; break; }
+        if (!nd) return {};
+
+        nlohmann::json cfg = nd->params;
+        cfg["node_id"] = nd->id;
+        for (const auto& e : edges) {
+            nlohmann::json port = e.format;
+            port["id"] = e.id;
+            if (e.from_node == node_id) cfg[e.from_port] = port;
+            if (e.to_node   == node_id) cfg[e.to_port]   = port;
+        }
+        return cfg;
+    }
+};
+
+} // namespace dmf