This simulation demonstrates how computers render lines on a pixel grid using Bresenham's Line Rasterization Algorithm. You'll see the step-by-step process of how the algorithm decides which pixels to illuminate to create a line.

Step-by-Step Procedure

1. Setting Up the Line:

   • Enter the coordinates for two points that define your line:
     • Point 1 (Start Point): Enter x and y coordinates
     • Point 2 (End Point): Enter x and y coordinates
   • Coordinate ranges:
     • x-coordinates: -45 to 43
     • y-coordinates: -23 to 21
   • Click "Submit" to initialize the simulation

2. Understanding the Display:

   • The canvas shows a pixel grid with:
     • A yellow line connecting your points
     • Red dots marking the start and end points
     • Grid lines for reference
   • The left panel shows:
     • Your input coordinates
     • Algorithm information (decision parameter and pixel direction)
     • Step-by-step messages
   • The right panel displays the sequence of chosen pixel coordinates

3. Running the Simulation:

   • Click "Next" to proceed through the algorithm steps
   • At each step, you'll observe:
     1. Candidate Pixels:
        • Blue highlights show possible next pixels
        • These represent the algorithm's choices
     2. Selected Pixel:
        • Green highlight shows the chosen pixel
        • Red highlight shows the rejected option
     3. Algorithm Information:
        • Current decision parameter value
        • Direction of the chosen pixel (East, North-East, etc.)
     4. Step Message:
        • Explains the current decision
        • Shows the coordinates of the chosen pixel

4. Understanding the Algorithm:

   • Watch how the decision parameter influences pixel selection
   • Observe how the algorithm chooses between:
     • Moving horizontally (East)
     • Moving diagonally (North-East, South-East)
     • Moving vertically (North, South)
   • The decision parameter helps determine which pixel is closer to the ideal line

5. Navigation Controls:

   • "Next": Move forward through the algorithm steps
   • "Prev": Go back to the previous step
   • "Reset": Start over with new coordinates

6. Observing Results:

   • The right panel shows the complete path of chosen pixels
   • Each step's message explains the reasoning
   • The algorithm information helps understand the decision-making process
   • The final result should show a continuous line of pixels approximating your input line

Tips for Better Understanding

• Start with simple lines (horizontal or vertical) to understand basic movement
• Try diagonal lines to see how the algorithm handles different slopes
• Pay attention to the decision parameter values and how they change
• Notice how the algorithm maintains visual continuity of the line
• Use the "Prev" button to review important steps

Expected Outcomes

• A continuous line of pixels connecting your start and end points
• Smooth visual appearance despite the discrete nature of pixels
• Efficient pixel selection that minimizes deviation from the ideal line
• Clear understanding of how the algorithm makes decisions at each step