drawLine method
draw a line using Bresenham's line algorithm
Implementation
void drawLine(int x0, int y0, int x1, int y1, bool color) {
final dx = (x1 - x0).abs();
final sx = x0 < x1 ? 1 : -1;
final dy = (y1 - y0).abs();
final sy = y0 < y1 ? 1 : -1;
var err = (dx > dy ? dx : -dy) / 2;
while (true) {
drawPixel(x0, y0, color);
if (x0 == x1 && y0 == y1) break;
final e2 = err;
if (e2 > -dx) {
err -= dy;
x0 += sx;
}
if (e2 < dy) {
err += dx;
y0 += sy;
}
}
}