I recently read a review of Ocularis, that had an interesting complaint. It takes 3 mouse clicks to replace the camera in a viewport in Ocularis, and we don’t offer a panel to be semi-permanently displayed on the screen like others clients. The idea is that dragging and dropping from a panel is easier than 3 mouse clicks. The math being, that when using a panel, you are not using “clicks” but “actions”, and “clicks” should be avoided. I think that argument is flawed, and I’ll explain why.
Fitts’ Law
In 1954, Paul Fitts suggested that the time it takes to click on something is dependent on the distance traveled and the size of the target. That’s pretty easy to understand, and it also means that all clicks are not created equal. Some are simply more expensive than others. The cheapest targets to acquire are the corners of the screen, and where the mouse is currently located. To get to the lower left corner, you simply move the mouse in a left-down direction, and without aiming, you will hit the lower-left corner of the screen.
With Fitts’s law in mind, it is clear that merely counting clicks and actions is too simplistic. From a scientific standpoint, simply counting clicks is no reasonable gauge of usability.
Math
Ocularis requires the following steps :
- Click on the viewport you want to change
- Select “Camera”
- Pick from list
Clicking on a viewport is a very easy operation, and so is selecting “Camera” (the distance is short, and the target is big). In my opinion, these 2 clicks are very cheap. But if mouse-clicking is not your cup of tea, you can always map a short-cut to show the camera list, thereby avoiding 2 mouse clicks.
Using a panel
- Move mouse to camera icon/label
- Drag and Drop to viewport
This seems easy. Hitting the camera sounds simple enough, but keep in mind that you may need to move your mouse quite some distance, and that the target is quite small. Once you’ve found your camera, you need to move your mouse again to hit the viewport, and so the cost of that is comparable to Step 1 in Ocularis.
As a thought experiment, consider a situation where you got the wrong camera. What would you prefer? 2 mouse clicks right where you are, or moving the mouse across the screen once again?
Picking Cameras
Ocularis shows a linear list of cameras, so finding a camera in a list of 2000 cameras, you would imagine that you’d have some difficulty. The overwhelming list is easily filtered though; typing a few keystrokes will filter the list to a small number of cameras, making it a lot easier to pick the correct camera. If you miss this crucial feature, you will clearly be at a disadvantage. In the clip below (best viewed full-screen) at the 1:55 point, you can see the filtering in action.
In the traditional tree control you will need to know – a priori – which folder the camera is in. If you have a large tree, you may find yourself opening and closing folders, scrolling up and down, trying to find a particular camera. You may find yourself asking, did the admin put the reception camera in the “Entrance” or “South Wing” folder. And if there are even 10 cameras in each folder, you may spend a considerable amount of time searching if the camera is NOT in the folder.
Wasting Space
Not only does the panel take up space for an operation you should rarely need (ideally the system sends the cameras to you when you need to watch them), but it also messes up the aspect ratios, causing a secondary loss due to letterboxing. I’ve made a few wireframes to illustrate this aspect. Keep in mind the wireframes are just wireframes, the scale is not 100% accurate.
Now, you may argue that you can show/hide the panel, but then we must update our click-math above to reflect this new operation.
Conclusion
Some people hold on to what they are used to, and that’s fine by me. If time permits, we’ll cater to those folks too. But Ocularis primary design goal is to make it simple for all users – not just the user that is going to use our software once in their life. We know that we are sometimes have some un-orthodox methods and that people need to see a feature in order for them to understand that it exists. Even then, one of the praises I hear quite often is that it is easy and fast to train new personnel in using Ocularis, and it takes just a few clicks on our web page to get to the tutorials.
As we move forward, we are going to continue to improve the UI. We have a bunch of ideas in the backlog, and I am confident that we can offer a compelling solution.
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