Revision history [back]

I found the reason, the reason is I ignored the resolution of the map data.

I thought the origin.position both represented the coordinates of the lower left and upper right corners. So If I get x:-5, y:-4 of the map origin's position data, I just thought the right and top coordinate is (5,4). This is wrong.

The position of the origin just represented the coordinates of the lower left. The real width of the map in ros is info.resolution * info.width . In the above question, it's 0.0500000007451 * 100. So the width of the map is about 5. It means the right coordinate is 0 instead of 5 ( width of the ros map + origin.position = right coordinate)