On the Match three game, I’m at the point where I need to be able to click on a piece and drag it to the next piece (horizontal or vertical) and then start the two animating to swap positions.

In SDL, I’ve got a simple mouseclick function that is called from ProcessEvents (my function for handling all input) with the x,y coordinates on the screen where clicked. These have to be  converted from screen coordinates to board coordinates (or ignored if not on the board) to identify the piece clicked. However the mouse now needs to drag this piece to an adjacent piece.

As usual I’m not the first person to ask this and there’s a StackOverflow Question with an answer. So I’ll be following this answer and hopefully get it working. This is possibly the key mechanic in a MatchThree game so it’s important to get it right. After that I’ll get teh touchscreen working again which should in theory use the same code apart from reading the game controller..