I tried with 32bit and 16bit color and the same results on both (174). Maybe my machine has a non compatible video card (my machine is 6 years old).
I am trying to write a simple obstacle/snake game where 2 lines are growing with time, and each player control the direction of one line and trying to avoid hitting itself or the opponent or the fence around. I was thinking of using GetPixelColor to find out if the next pixel to draw on next the snake/line is already taken, and the player lose. I guess I will need to come up with alternative method. (maybe using a huge 2D boolean array to hold values for pixels: True - pixel is a wall/line, False - pixel is free and the line can pass through. ANy other ideas are welcome.