Project Goal: To build an open source cross-platform Fusion 360 3D CAD clone using C++, Qt, and OpenGL. Features should be as close to Fusion 360 as possible. Development Summary: 1 Initial Setup: We created the basic application structure with a MainWindow class. This window was set up with a top toolbar to act as a banner for tools and a central widget area as a placeholder for the 3D viewport. 2 3D Viewport Implementation: We created a ViewportWidget class (inheriting from QOpenGLWidget) to handle 3D rendering. This widget replaced the initial placeholder. To test functionality, we rendered a simple, multi-colored 3D cube in the center of the viewport. 3 Camera Controls: We implemented mouse-based camera controls in the ViewportWidget: • Zoom: Mouse scroll wheel. • Rotate: Middle mouse button drag. • Pan: Shift + Middle mouse button drag. 4 View Cube: We added a view orientation cube (like in Fusion 360) to the top-right corner of the viewport. • The first version used QPainter to draw 2D text labels ("TOP", "FRONT", etc.) over the 3D cube. • We then improved this by rendering the labels as textures directly onto the faces of the 3D view cube, so they rotate with the cube. 5 Refactoring: To improve code organization, all logic related to the view cube (drawing, texturing, and axis lines) was extracted from ViewportWidget into its own dedicated ViewCube class. 6 UI Toolbar: We implemented a tabbed toolbar in the MainWindow to mimic the Fusion 360 UI. • Created "SOLID", "SURFACE", and "TOOLS" tabs. • Added "Create Sketch" and "Extrude" QToolButtons to the "SOLID" tab, complete with custom SVG icons loaded via a Qt resource file (.qrc). 7 Code Cleanup & Bug Fixes: • Removed the initial colorful test cube from the main scene. • Fixed a build error caused by a typo (QMatrix4xá4 instead of QMatrix4x4) that was introduced during the cleanup. • Resolved a Qt6 compatibility issue by replacing a legacy Qt5 OpenGL header include with its modern equivalent.