1 files changed, 39 insertions, 0 deletions
diff --git a/src/topology.c b/src/topology.c
new file mode 100644
index 0000000..10fc53f
--- /dev/null
+++ b/src/topology.c
@@ -0,0 +1,39 @@
+#include "cad/topology.h"
+#include "cad/util.h"
+
+#include <string.h>
+
+static void topo_resize(struct topology *topo, uint64_t newcapacity) {
+	resize_buffer((void**)&topo->elements, &topo->capacity, newcapacity, sizeof(struct topology_elem));
+}
+
+size_t frag_len(struct topology_elem *elems) {
+	struct topology_elem *cur = elems;
+	while(cur->cmd.op != TOPO_END) {
+		switch(cur->cmd.op) {
+			case TOPO_MOVETO:
+				cur += 2;
+				break;
+			case TOPO_LINETO:
+				cur += 2;
+				break;
+			case TOPO_ARCTO:
+				cur += 3;
+				break;
+			case TOPO_END:
+				abort();
+		}
+	}
+
+	return cur - elems;
+}
+
+void add_fragment(struct topology *topo, struct topology_elem *new) {
+	size_t new_num = frag_len(new);
+	if(new_num + topo->length > topo->capacity) {
+		topo_resize(topo, new_num + topo->length);
+	}
+
+	memcpy(topo->elements + topo->length, new, new_num * sizeof(struct topology_elem));
+	topo->length += new_num;
+}