jshaffer

A critical element of any game that must be considered carefully when designing and developing is the
movement and controls. The decision will affect every aspect of the game and
the very feel of play. There are as many
movement styles as there are game types. Ranging from the simple run-and-jump
of a platformer to the head-scratchingly complicated schemes that allow precise
control in flight simulators. In our case we chose a relatively simple setup
that works off of lines. When the player drags from fixbot to a point on the
screen a line is projected out in front of his finger that collides with walls
and objects in that direction. When he releases his finger fixbot is rotated to
a correct landing angle and moved through space to the new wall.

To handle the movement from the code side we use a modified version of the Cocos 2D engine's built-in
movement and rotation actions. By starting from a pre-built engine we avoided a
lot of the risk of redesigning the proverbial wheel. Of course even with the
assistance Cocos was, it still didn't solve all the issues we had but luckily
we were able to reuse a lot of the math work that we did for the surfaces in
the level. In fact, the most difficult math came into play with adjusting
player rotation after launching to a new surface. By dragging a line from the
player to one of the level surfaces we calculate distance to the point of
collision and once the player releases we launch them down that line until they
land safely (or so they hope) on another surface. Getting the correct rotation
required a healthy smattering of linear algebra and geometry but the less said
about those dark times the better.

Because controls dictate how the player interacts with the game they color his entire experience and
directly affect his enjoyment. It is therefore important to make sure that the
control scheme chosen matches the goals for the game.

Original Post @ Demergostudios.com