Add basic functionality to draw instances

Allows creation of instances of meshes and drawing all of them with
single draw call. Instances can have their own transformation data
(location, rotation and scale).

graphics/src/mesh_controller.cpp

@@ -0,0 +1,75 @@
+#include "mesh_controller.hpp"
+
+#include <map>
+#include <queue>
+#include <memory>
+
+namespace rse::graphics::mesh
+{
+
+std::map<uint16_t, struct Mesh> g_meshes;
+std::queue<uint16_t> free_ids;
+
+std::map<uint16_t, std::queue<uint16_t>> instance_free_ids;
+
+uint16_t create_mesh(std::vector<rse::graphics::vulkanbase::Vertex> vertices, std::vector<uint16_t> indices)
+{
+    static uint16_t last_id = 0U;
+    uint16_t assignable_id = 0U;
+
+    if (free_ids.empty()) {
+        assignable_id = last_id++;
+    } else {
+        assignable_id = free_ids.front();
+        free_ids.pop();
+    }
+
+    g_meshes.emplace(assignable_id, Mesh (
+        assignable_id,
+        vertices,
+        indices
+    ));
+
+    return assignable_id;
+}
+
+void create_mesh_instance(uint16_t mesh_id, InstanceData instance_data)
+{
+    uint16_t instance_id = 0U;
+    auto& instances = g_meshes[mesh_id].instances;
+    auto& free_instance_ids = instance_free_ids[mesh_id];
+
+    if (free_instance_ids.empty()) {
+        instance_id = instances.size();
+    } else {
+        instance_id = free_instance_ids.front();
+        free_instance_ids.pop();
+    }
+
+    instances[instance_id] = std::make_unique<struct MeshInstance>(
+        instance_id,
+        instance_data
+    );
+}
+
+//TODO: Replace with something else. It will take to much time to do this each time we draw frame for all the objects
+std::vector<InstanceData> get_instance_data_for_mesh(uint16_t mesh_id) {
+    std::vector<InstanceData> data;
+
+    for(const auto& [id, instance] : g_meshes[mesh_id].instances) {
+        data.push_back(instance.get()->instance_data);
+    }
+
+    return data;
+}
+
+
+std::vector<rse::graphics::vulkanbase::Vertex> get_mesh_vertices(uint16_t mesh_id) {
+    return g_meshes[mesh_id].vertices;
+}
+
+std::vector<uint16_t> get_mesh_indices(uint16_t mesh_id) {
+    return g_meshes[mesh_id].indices;
+}
+
+} // namespace rse::graphics::mesh