Blocks and flowgraph: added this time

oxydsp-flowgraph/src/graph.rs

@@ -0,0 +1,28 @@
+use crate::block::GraphableBlock;
+
+pub struct FlowGraph
+{
+    blocks: Vec<Box<dyn GraphableBlock + Send + 'static>>,
+}
+
+impl FlowGraph
+{
+    pub fn new() -> Self
+    {
+        FlowGraph { blocks: vec![] }
+    }
+
+    pub fn add_block<T: GraphableBlock + Send + 'static>(&mut self, block: T)
+    {
+        block.set_index(self.blocks.len());
+        self.blocks.push(Box::new(block));
+    }
+}
+
+impl Default for FlowGraph
+{
+    fn default() -> Self
+    {
+        Self::new()
+    }
+}