GLFW-style infinite mouse movement in SDL2?

Question

GLFW has a function which does exactly what I need:

glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);

This function lets the mouse to move freely without being bounded to the window or the screen.

One solution I found is to reset the mouse position each frame using:

 SDL_WarpMouseInWindow(window, defaultMousePositionX, defaultMousePositionY);

But I would still like to know If there is something like glfwSetInputMode() in SDL2.

Answer 1

If you require relative movement, FPS style, SDL has a SDL_SetRelativeMouseMode function as seen here . This forces SDL to only report motion events, so the mouse position doesn't change.

Another method would be to track the current and next positions yourself and manually calculating the differential, to get the distance moved.

// Last position
lastX = currX;
lastY = currY;

// Current position
currX = event.motion.x;
currY = event.motion.y;

// Motion
motionX = currX - lastX;
motionY = currY - lastY;

This could translate smoothly to other control methods too, like analogue sticks and touch controls, giving you a more uniform experience should you decide to use other platforms.