<p>Note that in your Dark Souls example, all the resolutions listed are the exact same aspect ratio.  So the question is, why doesn't it support arbitrary aspect ratios?  </p>

<p>The answer is that it costs time and effort to support arbitrary aspect ratios, and if that money spent doesn't translate to increased profit, then it doesn't make sense to do.</p>

<ul>
<li><p>This <a href="http://gamedev.stackexchange.com/a/125316/26734">answer</a> covers the 2d layout issues, which includes extra time and effort to create a versatile layout that can be resized so that elements do not overlap, stretch, or pixelate in an undesired manner, and that the overal UI maintains the best user experience.</p></li>
<li><p>The developer would have to ensure that the window doesn't get too large or too small.  Does it make the game any better if the user can drag the window size to be smaller than 800 x 450?  probably not.</p></li>
<li>you have to define the behavior of the camera when the aspect ratio changes. </li>
</ul>

<p>For example, take the following scene:</p>

<p><a href="https://i.sstatic.net/5YUYg.png" rel="noreferrer"><img src="https://i.sstatic.net/5YUYg.png" alt="Original Aspect Ratio"></a></p>

<p>If we allow the user to change the horizontal size, we can decide to "zoom out" horizontally so that the same area still shows up horzontally but now we can see more vertically.</p>

<p><a href="https://i.sstatic.net/998Of.png" rel="noreferrer"><img src="https://i.sstatic.net/998Of.png" alt="enter image description here"></a></p>

<p>Or, instead, we can keep the same zoom level but just clip the viewing area more:</p>

<p><a href="https://i.sstatic.net/cHGce.png" rel="noreferrer"><img src="https://i.sstatic.net/cHGce.png" alt="enter image description here"></a></p>

<p>Note, that if you don't specifically handle the changing aspect ratio, the default graphics pipeline behavior will be to stretch the image:</p>

<p><a href="https://i.sstatic.net/jJbqG.png" rel="noreferrer"><img src="https://i.sstatic.net/jJbqG.png" alt="enter image description here"></a></p>

<p>These decisions take time and effort to design, code and test, but management has to decide if it actually makes the user experience better enough to be worth the time.  Apparently, most games have decided its not worth the effort.  I'd even go further and suggest that allowing users to screw up the best layout of the game is a bad feature.</p>

CC BY-SA 3.0
2017-06-20T07:57:02.083Z
Interesting point. Does this mean Dark Souls will run distorted on screens with different aspect ratios (e. g. an old 800x600)? I think the fact that they all have the same ratio might be due to what @Alan Wolfe said in the comments, that these are only those supported by my hardware on full screen mode.
piegames
CC BY-SA 3.0
2017-06-20T11:50:27.963Z
As a specific example, in the 2d game [slither.io](http://slither.io/) there is a max distance you can see. In portrait, you can see this distance vertically, with your horizontal view restricted. In landscape, you can see this distance horizontally, with your vertical view restricted. If you resize the window to be perfectly square, then you can see the max distance both vertically and horizontally, giving a significant advantage over other players. In addition to the time and money required to adjust to different aspect ratios, it can also become a potentially undesirable meta game.
trichoplax is on Codidact now
CC BY-SA 3.0
2017-06-19T22:14:25.480Z
2017-06-19T22:24:19.707Z
2017-06-19T22:24:19.707Z
default
<p>Only a few games have resizable windows when running in full screen mode. All others have a finite fixed set of allowed resolutions. But why? I see some reasons, but none of them seems to be that important to me that would justify such a user-unfriendly feature.</p>

<p><strong>Example</strong></p>

<p>Let's use Dark Souls II, because it's the first I can think of. The allowed resolutions are:</p>

<pre><code>800x450
1024x576
1152x648
1280x720
1440x810
1600x900
1680x945
1920x1080
</code></pre>

<p>What is the reason to not allow the resolutions <code>800x451, 800x452, ..., 801x450, 801x451, ...</code>? What it I think can't be:</p>

<ul>
<li><strong>The UI.</strong> If we keep minimum and maximum window sizes as limitations, the only issue I can see here is with settings with a weird aspect ratio (1920x450, 800x1080). Otherwise, there shouldn't be any problems with free scaling between the resolutions.</li>
<li><strong>Camera, Viewport.</strong> Same as above.</li>
</ul>

CC BY-SA 3.0
2017-06-19T13:24:42.943Z
I would think part of it has to do with the layout of 2d elements on the screen.  If you allow the user to freely resize the screen then the elements could overlap.
default
CC BY-SA 3.0
2017-06-19T13:28:07.610Z
Someone who can't build a GUI that's scaling resistant shouldn't be allowed to build GUIs at all. Also, scaling is possible, but only in steps. So a little window where things might overlap is still possible, so why not sizes in between?
piegames
CC BY-SA 3.0
2017-06-19T13:30:45.260Z
Also, the 2d elements are often textures that are designed to be the right size for a certain screen resolution.  If the user arbitrarily blows up the screen size, those textures will stretch and look bad.  Instead, there are different textures for each supported resolution.
default
CC BY-SA 3.0
2017-06-19T13:34:15.813Z
This question is probably more appropriate for gamedev.stackexchange.com.  See https://gamedev.stackexchange.com/a/125316/26734
default
CC BY-SA 3.0
2017-06-19T13:56:13.407Z
I posted it here because I think this is mostly a graphical issue that just happens to appear mostly in games, but you might be right. Also, the answer on that question on gamdev isn't really satisfying.
piegames
CC BY-SA 3.0
2017-06-19T13:58:53.293Z
See also: https://gamedev.stackexchange.com/a/56952
piegames
CC BY-SA 3.0
2017-06-19T14:14:28.783Z
Not quite enough info for an answer, but we query the driver to ask for what resolutions will work in full screen mode.  The specific list of resolutions you give in dark souls 2 will vary from machine to machine. There are hardware and software (driver) limitations to what is available.
Alan Wolfe
CC BY-SA 3.0
2017-06-19T14:29:40.100Z
But why would they matter in windowed mode? And if the game takes all the resolution the system throws at them, does it mean the game in fact *is* resolution independent and the restriction is purely artificial?
piegames
CC BY-SA 3.0
2017-06-19T18:25:28.247Z
If you find the linked answer unsatisfying, you might be more likely to get the answer you seek if you edit the question to explain why you are not satisfied with the reasons given. That way you can avoid getting the same answer here.
trichoplax is on Codidact now
<rendering><frame-buffer>
Why do games only allow certain resolutions?
piegames
# Why do games only allow certain resolutions?

(Asked by: username_0 on 2017-06-19)

Only a few games have resizable windows when running in full screen mode. All others have a finite fixed set of allowed resolutions. But why? I see some reasons, but none of them seems to be that important to me that would justify such a user-unfriendly feature.

**Example**

Let's use Dark Souls II, because it's the first I can think of. The allowed resolutions are:

```
800x450
1024x576
1152x648
1280x720
1440x810
1600x900
1680x945
1920x1080

```

What is the reason to not allow the resolutions `800x451, 800x452, ..., 801x450, 801x451, ...`? What it I think can't be:

* **The UI.** If we keep minimum and maximum window sizes as limitations, the only issue I can see here is with settings with a weird aspect ratio (1920x450, 800x1080). Otherwise, there shouldn't be any problems with free scaling between the resolutions.
* **Camera, Viewport.** Same as above.

**Tags:** rendering, frame-buffer

> **Comments:**
> **username_1**: I would think part of it has to do with the layout of 2d elements on the screen.  If you allow the user to freely resize the screen then the elements could overlap.  
> **username_0**: Someone who can't build a GUI that's scaling resistant shouldn't be allowed to build GUIs at all. Also, scaling is possible, but only in steps. So a little window where things might overlap is still possible, so why not sizes in between?  
> **username_1**: Also, the 2d elements are often textures that are designed to be the right size for a certain screen resolution.  If the user arbitrarily blows up the screen size, those textures will stretch and look bad.  Instead, there are different textures for each supported resolution.  
> **username_1**: This question is probably more appropriate for gamedev.stackexchange.com.  See https://gamedev.stackexchange.com/a/125316/26734  
> **username_0**: I posted it here because I think this is mostly a graphical issue that just happens to appear mostly in games, but you might be right. Also, the answer on that question on gamdev isn't really satisfying.  
> **username_0**: See also: https://gamedev.stackexchange.com/a/56952  
> **username_2**: Not quite enough info for an answer, but we query the driver to ask for what resolutions will work in full screen mode.  The specific list of resolutions you give in dark souls 2 will vary from machine to machine. There are hardware and software (driver) limitations to what is available.  
> **username_0**: But why would they matter in windowed mode? And if the game takes all the resolution the system throws at them, does it mean the game in fact *is* resolution independent and the restriction is purely artificial?  
> **username_3**: If you find the linked answer unsatisfying, you might be more likely to get the answer you seek if you edit the question to explain why you are not satisfied with the reasons given. That way you can avoid getting the same answer here.  

---

## 1 answers

### Answer by username_1 on 2017-06-19. Score: 7

Note that in your Dark Souls example, all the resolutions listed are the exact same aspect ratio. So the question is, why doesn't it support arbitrary aspect ratios?

The answer is that it costs time and effort to support arbitrary aspect ratios, and if that money spent doesn't translate to increased profit, then it doesn't make sense to do.

* This [answer](http://gamedev.stackexchange.com/a/125316/26734) covers the 2d layout issues, which includes extra time and effort to create a versatile layout that can be resized so that elements do not overlap, stretch, or pixelate in an undesired manner, and that the overal UI maintains the best user experience.
* The developer would have to ensure that the window doesn't get too large or too small. Does it make the game any better if the user can drag the window size to be smaller than 800 x 450? probably not.
* you have to define the behavior of the camera when the aspect ratio changes.

For example, take the following scene:

[![Original Aspect Ratio](https://i.sstatic.net/5YUYg.png)](https://i.sstatic.net/5YUYg.png)

If we allow the user to change the horizontal size, we can decide to "zoom out" horizontally so that the same area still shows up horzontally but now we can see more vertically.

[![enter image description here](https://i.sstatic.net/998Of.png)](https://i.sstatic.net/998Of.png)

Or, instead, we can keep the same zoom level but just clip the viewing area more:

[![enter image description here](https://i.sstatic.net/cHGce.png)](https://i.sstatic.net/cHGce.png)

Note, that if you don't specifically handle the changing aspect ratio, the username_1 graphics pipeline behavior will be to stretch the image:

[![enter image description here](https://i.sstatic.net/jJbqG.png)](https://i.sstatic.net/jJbqG.png)

These decisions take time and effort to design, code and test, but management has to decide if it actually makes the user experience better enough to be worth the time. Apparently, most games have decided its not worth the effort. I'd even go further and suggest that allowing users to screw up the best layout of the game is a bad feature.

> **Comments:**
> **username_0**: Interesting point. Does this mean Dark Souls will run distorted on screens with different aspect ratios (e. g. an old 800x600)? I think the fact that they all have the same ratio might be due to what @username_2 said in the comments, that these are only those supported by my hardware on full screen mode.  
> **username_3**: As a specific example, in the 2d game [slither.io](http://slither.io/) there is a max distance you can see. In portrait, you can see this distance vertically, with your horizontal view restricted. In landscape, you can see this distance horizontally, with your vertical view restricted. If you resize the window to be perfectly square, then you can see the max distance both vertically and horizontally, giving a significant advantage over other players. In addition to the time and money required to adjust to different aspect ratios, it can also become a potentially undesirable meta game.  

---

