[Feature Request] Mouse support?

[teadrinker]

mouse support is great for quickly exploring a parameter space (2 variables) interactively.

currently the mouse cursor is hidden, I feel this could still be the behaviour, no need to support built-in cursor (if you want to a graphical cursor, you have to draw it yourself)

for good behavior in a browser or window, I think it's important that the coordinate range is not clamped to 320x240. Also, if the mouse is clicked inside the screen ("mouse-capture") and dragged out, mouse buttons should still report as down when cursor is outside 320x240

maybe something like this? (aligns with tic-80):

float mouseX();
float mouseY();
unsigned int mouseButtons(); // 1 = left, 2 = middle, 4 = right
float mouseScrollX();
float mouseScrollY();

(Float precision is nice cos it enables subpixel accuracy for higher resolutions)