DRAWING ROBOT NXT-G (need some help)

[muntoo]

Basic structure of program:

• Read black & white image file
  • Read header
    • Width
    • Height
• Read a horizontal line in the image file
  • If pixel is black
    • Make the pen touch the paper
    • Make a rectangular/circular motion (depends on the writing tool)
    • Move pen back up
  • Move motor right by a tiny amount (one pixel)
• If there is another line, move the motor down one pixel, and back to the left by [width] pixels
• Go back to the instruction Read a horizontal... until all lines have been read

In C, this is something like:

Code: Select all

ReadFileHeader("filename.pic", &width, &height);

for(y = 0; y < height; ++y)
{
    for(x = 0; x < width; ++x)
    {
        if(ReadFileNextByte() == BLACK)
        {
            MovePen(DOWN);
            MoveHand(CIRCLE_MOTION);
            MovePen(UP);
        }
        
        MoveHand(RIGHT, 1);
    }
    
    MoveHand(LEFT, width);
    MoveHand(DOWN, 1);
}

What happens in that program is: you determine the width and height of the image (Line 1); loop through each horizontal line (Line 3); loop through each pixel (Line 5); draw the pixel if it is black (Line 7); and move the hand holding the pen into the proper positions.