Coding Challenge: 3D on Apple II

Step-by-Step Tutorial: Creating a 3D Rotating Cube on Apple II

1. Understanding Variable Naming in Apple BASIC

   • Variable names in Apple BASIC are limited to two characters.
   • Demonstration: Creating variables startX and startY and printing their values.

2. Exploring Beagle Brothers BASIC Enhancements

   • Beagle Brothers BASIC was an enhancement utility for Apple II.
   • Highlighting the swap command for variables.

3. Navigating and Editing in Apple II BASIC

   • Using the escape key and arrow keys to navigate and edit code lines.
   • Utilizing shortcuts to move the cursor efficiently.

4. Implementing Double Buffering for Animation

   • Explaining the concept of double buffering for smoother animation.
   • Setting up two high-resolution graphics pages for off-screen drawing.

5. Animating a Moving Line

   • Writing a program to animate a line moving across the screen.
   • Implementing a subroutine to switch between drawing pages.

6. Drawing a 3D Cube

   • Planning the coordinates for a 3D cube on a 2D screen.
   • Creating arrays for points and lines to construct the cube.

7. Applying 3D Rotations

   • Understanding the math behind 2D rotation transformations.
   • Implementing rotation matrices for X, Y, and Z axes in the code.

8. Completing the 3D Cube Rendering

   • Updating the program to rotate and draw the 3D cube.
   • Connecting all points to form the complete cube shape.

9. Optimizing the Code

   • Discussing optimization techniques like pre-computing values and erasing lines individually for faster performance.
   • Encouraging experimentation and feedback for further improvements.

10. Exploring Further Challenges

    • Hinting at future challenges like perspective projection for advanced 3D rendering.
    • Providing links to the emulator and code for hands-on exploration.

By following these steps, you can recreate the process of rendering a 3D rotating cube on an Apple II using BASIC programming. Feel free to experiment, optimize, and expand upon the provided code to enhance your understanding of computer graphics and programming concepts.