diff --git a/doc/tutorial_imgs/4-0.png b/doc/tutorial_imgs/4-0.png
new file mode 100644
index 0000000..54acbfc
Binary files /dev/null and b/doc/tutorial_imgs/4-0.png differ
diff --git a/doc/tutorial_imgs/4-1.png b/doc/tutorial_imgs/4-1.png
new file mode 100644
index 0000000..ff7de05
Binary files /dev/null and b/doc/tutorial_imgs/4-1.png differ
diff --git a/doc/tutorial_imgs/4-2.png b/doc/tutorial_imgs/4-2.png
new file mode 100644
index 0000000..e30dc54
Binary files /dev/null and b/doc/tutorial_imgs/4-2.png differ
diff --git a/doc/tutorial_imgs/4-4.png b/doc/tutorial_imgs/4-4.png
new file mode 100644
index 0000000..f47ae3d
Binary files /dev/null and b/doc/tutorial_imgs/4-4.png differ
diff --git a/doc/tutorial_imgs/5-3.png b/doc/tutorial_imgs/5-3.png
new file mode 100644
index 0000000..0176689
Binary files /dev/null and b/doc/tutorial_imgs/5-3.png differ