Those two images, although part of the same graphic, are not the same scale! When I put any of my P99s next to a Glock 32 (same size as a Glock 19), the P99 is taller. That photo is misleading. The P99 is 5.37 inches high, but the Glock 19 (and 23 and 32) are only 5 inches high. They are made to be the same height in the photo. I really like the P99, and own four of them, but they need to be compared fairly.
I find that the P99 is somewhere between the G17 and G19 in length and height.