We encourage you to discuss the assignments with other students. However, you should not share any of your codes with anyone else.  Each student is responsible for implementing the assignment on their own.   You may assist other in debugging their codes, but you should not copy  and  paste.   ANU  is  using  Turnitin  to  detect  possible  duplications.    Consulting  with previous year students who enrolled in this course on specific assignment is also not allowed. You may use the internet as a resource for learning the materials, but you should not borrow any existing codes found online.

The homework assignments involve a significant amount of C/C++ programming.  However, for most cases, a skeletal code base is provided, and you only need to fill in the missing parts, and/or fix bugs if any.

You will submit a single ZIP file as your submission, which must contain the following files:

(1) All source codes (ending in .h, or .hpp, or .cpp), and CMakeLists.txt.     Please include all   needed   source   codes   for   successful   compilation.    Please   also    remove   all intermediate files and folders (such as  .vscode/ and build/)  that are not needed for the compilation –  Failing to do so will lead to penalty to the marks.

(2) A written CLab1-Report (minimum 10-point font size, single column A4, in PDF format, with task statement, methods used, any new features that you have implemented, any known bugs in your code,  answer any questions that have been asked in the task, instruction for the tutor to use your code,  example experiment results. )

Your ZIP file must be named as “COMPX610_2024_HW1_UID.zip” .    Replace ‘X’ with 4 or 8. Replace  the  UID  with  your  Uxxxxxxxx;  Please  submit  your  ZIP  file  to  Wattle  before  the deadline.  Late submission will lead to penalty as per the ANU policy.     Later-than-one-week submission will not be accepted, which may result zero mark, unless a pre-approval for special consideration is obtained in written before the submission deadline.

Tasks for HW1:

Task-1: C/C++ Programming Basics

We will introduce basic C/C++ programming knowledge including development environment, fundamental  syntax  and  constructs  of  C/C++  project  that  will  be  used  in  the  homework assignments.  If you come across any further problems with C/C++, please refer to online resourcesC++ documentation — DevDocs,Stack Overflow – Where Developers Learn, Share, & Build Careersor post on Ed Forum.

1.1 Development Environment

We use Visual Studio Code (VSCode) as our IDE (Integrated Development Environment). It’s already installed and set up in the virtual machine. You can use VSCode to open your project.

1.2 C++ Programming

1.2.1    Basic programming

First, you need to include essential header files at the front of the code.

Define a main function as the entry of your program.

Call some mathematic functions.

1.2.2    Vector manipulation with Eigen library

Eigen is  a  C++  library  for  linear  algebra,  matrix  and  vector  operations.  Please  refer  to use_eigen.cpp for some common usage of Eigen and more information atEigen: Quick reference guide.

1.3     Organize your project with CMake

CMake is an open-source, cross-platform family of tools designed to build, test and package software. CMake is used to control the software compilation process using simple platform and compiler independent configuration files and generate native makefiles and workspaces that can be used in the compiler environment of your choice.

1.3.1    Writing a CMakeLists.txt

CMake  uses  a  configuration  file  called  CmakeLists.txt  to  organize  a  project.   Below  is  a minimum example of CmakeLists.txt with detailed comments.

1.3.2    Configure with CMake

To use CMake in VSCode, press CTRL + SHIFT + P to open the Command Palette and select CMake: Configure.

Choose GCC as the project compiler.

Then,   VSCode   will   invoke   CMake   to   setup   the    project   according   to   the    provided CmakeLists.txt and generate a build folder under the project root directory.

Build the project in the terminal by cmake .. && make:

1.4 Debug with VSCode

Select a build target at the bottom status bar.

Set a breakpoint at the target line by click or press F9.

Press CTRL+F5 to start debugging.

1.5 Check if a point is inside a triangle:

In computer graphics, determining whether a point is inside a triangle on the plane is a very popular algorithm. You need to implement this algorithm according to the lecture in the provided code framework task1.cpp.

Task-2:  OBJ Mesh file I/O and operations:

Get  yourself  familiar  with  Wavefront   OBJ  file  format   by   reading  the  Wikipedia   page: Wavefront .obj file - Wikipedia.

You need to complete the following two sub-tasks:

(a)  Find the  provided  mesh Cottage.obj in the model folder and visualize it with MeshLab.

(b) Create a simple house mesh by hand (which means you can only create the mesh in a text editor without any 3D software) and save it as house.obj in the model folder. Basically, the house mesh should contain a cuboid base, a triangular prism roof and a

chimney. Note that you only need to create the vertices and faces of the mesh.

Figure: An example of a simple house mesh.

Task-3:   Spatial Transformations for Graphics Rendering

From the first two weeks, you have learned how to use transformation matrices to prepare an object for graphics rendering. Now it is time to put them into practice. In this task, we will create a house mesh and display it in the screen. You need to finish the task by following steps:

(a)  Implement  the  get_model_matrix function  that  calculates  a  transformation

matrix given the rotation angle, translation and scale.

(b)  Implement a draw_circle function according to the lecture slides.

(c)  Currently, the camera is fixed and always looking towards the -z direction.

Please update your code to enable camera movement by keyboard and ensure the camera is always looking at the origin. To do this, you may need to implement the look_at function and used it in the get_view_matrix function.

(d)  Run your code to see the result.

Task-4:   Spatial transformations

4.1. In order to perform geometric transformations of a rigid body in 3D space, we often use 4x4 homogeneous matrices. Write down any 4x4 matrix which represents a rigid Euclidean transformation and prove that your specific 4x4 matrix is indeed a rigid Euclidean transformation.

4.2. Write the homogeneous transformation matrix that rotates a point around the Y-axis by 90 degrees with the centre at point (2, 3, 4).    Please list the steps of your calculation.

4.3. Given the 3D cube mesh cube.obj with 12 triangles. Use this cube as the primitive    shape, write some C++ codes to model the following cubic dog using transformed primitive cuboids, and render it as wireframe.    Report your rendering result in your Lab report.

Figure: A dog modelled with translated, rotated, and scaled cuboids. (Courtesy of Morgan McGuire).