3D World Space
In the last tutorial we saw how the Left-Handed 3D Coordinate System worked. This is the coordinate system that we will use from now on. We will specify in our code (below) that the y axis points up.
What is the difference between left and right-handed coordinate systems? In left-handed coordinates, the positive z axis points away from you. In right-handed coordinates, the positive z axis points towards you. In both cases the positive y axis points up and the positive x axis points to the right. You can remember this by holding up your left hand so that the palm is facing up (y axis) and your fingers point to the right (x axis). Your thumb represents the positive z axis (points away). If you did the same with your right hand, your thumb would point towards you, hence left and right-handed coordinate systems. We will always use the left-handed system, this is what DirectX uses.