Add functionality to draw nodes with user-defined inputs count

include/nodes.h

@@ -5,6 +5,8 @@
 #include "ui.h"
 
 #define MAX_NODES 1024
+#define IO_INPUT_COUNT 0
+#define OP_INPUT_COUNT 2
 
 typedef i32 (*node_func)(i32 a, i32 b);
 typedef enum node_type node_type;
@@ -28,6 +30,7 @@ struct node {
   ui_elem_colours colours;
   node_type type;
   node_data data;
+  u64 inputs;
 };
 
 #endif // !NODES_H

include/ui.h

@@ -39,8 +39,9 @@ struct ui_elem_colours {
 
 typedef struct ui_node_elem ui_node_elem;
 struct ui_node_elem {
-  line noodle;
   rect rec;
+  line *noodles;
+  u64 inputs;
 };
 
 struct ui_ctx {