HOWTO Design your own Framebuffer Splash
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Introduction
This article is not about installing the framebuffer splash, or about configuring your kernel for framebuffer splash - there's plenty of documentation on that already, so get the emergence theme up & running before you try making your own themes. I'm assuming you've got that far before you proceed with designing your own layout.
I wrote this because I wanted to create my own theme, and although I found plenty of themes on the net (mostly for bootsplash used in older kernels) I couldn't find much documented about how to make my own - about the best I could find was "to have an idea how they should look like, have a look at the config files for the default theme". Well, that's what I did.
I don't plan on maintaining this article, so I'd be indebted if you would. Please correct errors & ommissions, but do so accurately - if this works for you, add the article to your watch list so that you can correct other Wikipaedians' spelling & grammer.
Starting out with a splash
Once you know your kernel & grub.conf work with splashutils, it's time to start making your own theme. I wanted to build one with my company logo on it, so unfortunately I can't post the trademarked graphics here - for this demo I'm going to use these (http://img45.exs.cx/img45/7186/silent1280x10247et.jpg) images (http://img18.exs.cx/img18/6623/bootsplash1280x10247vc.jpg) that _mikec_ (http://forums.gentoo.org/profile.php?mode=viewprofile&u=56632) on the forums was having some problems with. This picture isn't quite to my taste, but I hope Mike will forgive me for taking the mickey out of his design.
Try to create your image at high resolution, and only downsize as infrequently as possible. I had some problems with a jpeg created in Photoshop on my Mac, but I found that it worked perfectly when I shipped it over to the target machine as a bitmap & then converted it to jpeg using imagemagick. I couldn't get PNG images to work at all, but maybe I didn't test thoroughly - I later found that sometimes during the boot process (about one time in five) my kernel would hang just before loading the splashscreen but that I'd get no problem on a reboot. This is probably because of the slightly esoteric hardware I'm trying this on, but it may help you - if your kernel hangs on bootup, try a power-cycle.
Make all changes incrementally
When you're making changes to your .cfg files, make all changes incrementally - this means no fancy stuff initially, just add one component at a time & see if that works. If you start from scratch with a massive long .cfg file full of eye-candy and it doesn't work, how do you debug it?
Create a theme directory & artwork
I'm only working on one canvas-size to start with - this machine won't do a framebuffer larger than 1024x768, but you also don't want to be messing around with several sizes at once - get one working and then you can upscale the rest.
When you design your artwork, remember that the verbose screen will need to be mostly dark - the console text is a light grey which works great on black, but not so well on lighter colours. Is there any way to change that, short of modifying the kernel source?
| Code: Create a theme directory & artwork |
# mkdir -p /etc/splash/mytheme/images |
Create a theme .cfg file
Again, we're gonna keep this absolutely as simple as possible, and cut out all the cruft. We'll still have the original theme to refer back to, but don't worry right now about semi-transparent progress bars - let's just get it working. Just edit /etc/splash/mytheme/1024x768.cfg
| File: /etc/splash/mytheme/1024x768.cfg |
bgcolor=0 |
I think the above is about as simple as it gets - if you find that any
of these entries are unnecessary, please remove them from this page.
What the above says is:
- Set background colour to 0, IE no colour, black
- Set text frame:
- 25 pixels in from the left
- 28 pixels down from the top
- 979 pixels wide
- 728 pixels deep
- Paths to
- verbose background image
- silent background image
Note:You can find more options in /usr/share/doc/splashutils-*/theme_format.gz - I urge you to read this file and to keep it open for reference.
Edit GRUB
I'm using a fairly unusual RAID array here, so your root= sections will almost certainly be something different - probably something like root=/dev/hda3, I guess.
| File: /boot/grub/grub.conf |
timeout 15 |
Note that for the purposes of constructing the splash theme I'm always placing the initrd as a separate file in /boot,
rather than compiling it into the kernel. Sure we can compile it into
the kernel if we want to when we've finished laying it out, but at the
moment that just takes a few extra commands which slow us up - we're
gonna need to reboot quite a few times to get everything just how we
want it.
Install the theme to /boot & test
You'll find you're running the below commands quite frequently as you tweak the dimensions of your layout - I keep the two lines below close at hand in my history buffer:
| Code: Install the theme to /boot & reboot to test |
# mount /boot ; splash_geninitramfs -v -g /boot/fbsplash-mytheme-1024x768 -r 1024x768 \ |
Freaking ugly, isn't it? Looks to me like Mike is a programmer rather than a graphics designer - sorry, Mike! Don't give up the day job just yet!
But if I've got the instructions above right, and you've followed them
correctly, then it'll be booting up fine & displaying this picture
of a bird with a fat arse & a car appropriate for us Gentoo ricers (http://funroll-loops.org/).
If you just want to test the theme, edit /etc/conf.d/splash and go to vc1 (ctrl+alt+f2) and play around with the commands below:
| File: /etc/conf.d/splash |
# allows to set different themes on different consoles |
| Code: Test verbose mode |
# /etc/init.d/splash restart |
| Code: Test silent mode |
# splash_util --vc=1 -m s -t mytheme -c setcfg |
Getting the verbose text right
Ok... so now we've rebooted we can see the picture both in silent & verbose mode.
It's worth mentioning at this point that Mike probably didn't need to do the green Matrixesque tinting in his image program - splashutils offers improvements over the old bootsplash and does transparency & stuff. I think they probably do alpha-blending, too, except I'm not quite sure what that is.
The first thing to do is get the text fitting into the appropriate area in verbose mode. We do this using the tx=, ty=, tw= & th= settings.
It's interesting to note that these are the only commands in the theme format that don't define the box in terms of the x & y co-ordinates of its top-left & bottom-right corners. The verbose text box is defined by the x & y of it's top-left corner and by its width and height.
You can look in /usr/share/doc/splashutils-*/theme_format.gz for more details but the important thing to remember is that if your screen is 1024 pixels wide and you want the verbose text to be 15 pixels in from the left, but 20 pixels in from the right then tx=15 and tw=... erm... 1024 - (15 + 20)... erm... tw=989.
The first time I tried this I just copied & pasted the figures from Mike's posting (http://forums.gentoo.org/viewtopic-p-2203857-highlight-.html#2203857) on the Gentoo forums, and the verbose screen didn't display. These were Mike's settings:
tx=162
ty=110
tw=955
th=804
Now, I'm not sure if they worked for him, because the original image
he sent me was 1280x1024, but these figures won't work on my 1024x768
screen - the sum of tx and tw are more than 1024, and the y & height are more than 768.
Troubleshooting: if your system boots to a login prompt but
instead of your verbose screen being displayed you just get a black
framebuffer with white writing, check & ensure your height, width
and starting co-ordinates are sane relative to the screensize.
| File: /etc/splash/mytheme/1024x768.cfg |
bgcolor=0 |
Install the theme, reboot & test!
I'd like to say that this looked alright to me, but I didn't like to
examine Mike's artwork too closely. Suffice to say it boots & the
text came up & stuff.
Displaying a silent message
When the system boots in silent mode, we'd like to display some text saying "Hit f2 to show a bunch of Lunix stuff", just like all the other themes do.
The content of the text is defined in /etc/conf.d/splash, but the text size & colour is part of our theme. Let's edit our config:
| File: /etc/splash/mytheme/1024x768.cfg |
bgcolor=0 |
The only change I've made here is the addition of the text_x=, text_y=, text_size= & text_colour= lines.
Respectively these mean:
- text_x - left-hand edge of text, distance from left of screen.
- text_y - top edge of text, distance from top of screen.
- text_size - height of text in pixels.
- text_color (sic) - colour of the silent text in hex format. 0xffffff means "white"
It's worth observing another unusual case in the layout config here - nowhere else in the theme is the 0x needed before the hex colour code. I believe the 0x is technical for "this is a hex number, not a decimal one", but the colour for the progressbar & other boxes that we'll paint don't need that.
Install the theme, reboot & test!
Understanding hexadecimal colour codes
If you've designed webpages then you may already be familiar with hex colour codes, but here's a quick recap, just in case - you're going to need these throughout your theme.
The principle is that 2563 colours is plenty enough colours to satisfy any interior-decorator, and that hex is a convenient way of describing values between 00 and 255 without wasting any bits. Consequently we define our colour as (I think) RRGGBB, where RR is a value of red between 00 and FF, blended with an amount of green between 00 and FF, and mixed with some blue, too.
Examples:
- Absolutes:
- ffffff - white - all of all of the composite colours.
- 000000 - black - a distinct lack of colour.
- Greyscales:
- eeeeee - very light grey - nearly white, in fact.
- ddddd - light grey
- 999999 - 60% grey
- 333333 - 20% grey - quite dark
- 111111 - very dark - nearly black, in fact.
- Primaries
- ff0000 - bright red.
- 00ff00 - bright green.
- 0000ff - bright bloo.
- Composites
- ffff00 - bright yellow, a mix of red & green
- ff00ff - bright violet - a mixture of red & blue.
If you want a bunch of useful colours, a Google for "hex colour codes" should bring up a big bunch of useful colour tables (http://www.google.com/search?&q=hex+colour+codes)
Drawing a box
From /usr/share/doc/splashutils-0.9.1/theme_format.gz
|
box [flags] x0 y0 x1 y1 color1 [color2 color3 color4]
Flags:
x0, y0 - coordinates of the upper left corner of the box Colors are specified one of the following formats: If only color1 is specified, the box is filled with the color. If all four colors are specified, then:
and the box if filled with a gradient formed by these colors. |
| File: /etc/splash/mytheme/1024x768.cfg |
bgcolor=0 |
This box has the attributes:
- silent - displayed only when the splashscreen is in silent mode.
- noover - painted the first time the screen is shown and then never updated.
- Corners:
- Top left:
- 300 pixels from the left edge of the screen
- 750 pixels from the top edge of the screen
- Bottom right:
- 824 x 768 - so the box covers approximately the middle third of the screen horizontally, but only the bottom few pixels.
- Top left:
- Black
If you've scaled the original artwork (http://img45.exs.cx/img45/7186/silent1280x10247et.jpg) to 1024x768 and you're following along, then you'll see why I've drawn this box. Those that are paying attention will see that I've also moved the silent text correspondingly.
Note: this didn't seem to work properly when the text started inside the box, but does so perfectly when the text starts above the top of the box. I have no idea why this might be.
Don't forget to install the theme, reboot & test!
Defining the progressbar
I think the next thing we want to do is get the progressbar working, if nothing for no other reason than to cover that fat bird's hideous arse... erm... I mean to protect the young lady's modesty.
I'm pretty sure there's some requirement about having a baselayout that supports splashutils here - I believe the progressbar is incremented to represent how far the system has proceeded through the active /etc/init.d/ events. I seem to recall reading that splashutils provide an interface for animation events, and so init scripts must call this interface in order to show progress - I presume this is what /etc/conf.d/splash is using to write the text to the splashscreen, too. I'd imagine that all current baselayouts do this correctly, but I don't know for sure - I'm using baselayout-1.11.10.
The critical part of the theme format for the progress bar is where it says "inter - The box will be interpolated with the following one, based on the value of progress". I can't really give a helpful definition of interpolation other than "mixing stuff together" - the best thing to do is look at an example:
| File: /etc/splash/mytheme/1024x768.cfg |
bgcolor=0 |
What these three additional lines basically say is:
- only in silent mode
- draw a box
- only a single pixel wide - from (300,350) to (300,418).
- interpolate it with the next box, based on progress.
- make it a suitable colour.
- draw another box
- from (300,350) to (824,418).
- make it the same colour.
- draw a box
So the first "box" is tiny - it's what's used to represent no progress at all, except that we never see the box that small, because it's not painted until the progress begins - I'd guess it's usually 5% or 10% wide when we first see it. The second box represents the completed progress - you'll see it full with when you run shutdown -hf now.
I reckon that, considering splashutils allows transparency, one could have a progress bar that gets darker during the progression. I haven't tried that, so implementation is left as an exercise for the reader.
Install the updated theme, reboot & test!
Drawing rectangles
Ok, so we've got the progressbar working, but it looks kinda lame... something's missing. How does the viewer know where 100% is? Let's draw a rectangle around the progressbar to show how full it is. There are two ways of doing this.
Solid filled
| File: /etc/splash/mytheme/1024x768.cfg |
bgcolor=0 |
It only takes a single additional line to do this - you can see how it's 3 pixels wider on each side than the progressbar and it's a contrasting colour. The noover option seems a bit of a misnomer to me - it doesn't prevent the box from being overwritten, but rather prevents it from overwriting other graphical items - such as the progressbar on the following two lines. Check it out!
Transparent
Well, that's all well & good, but some folks will want to see what's underneath the progressbar, at least while it's progressing.
Creating a transparent box doesn't work:
box silent noover 297 347 827 421 #dcdcdc
box silent noover 300 350 300 418 #000000ff
box silent inter 300 350 300 418 #ff00ff
box silent 300 350 824 418 #ff00ff
Because the box just shows what's underneath it - the plain rectangle we want as our progressbar border.
In fact, spock (http://dev.gentoo.org/~spock/index.php) shows us the way around this in his Emergence theme - take a look at /etc/splash/emergence/1024x768.cfg. In that he draws a 1-pixel wide "hollow rectangle" - it's not a single transparent rectangle, but rather 4 independent 1-pixel wide retangles forming a border.
| File: /etc/splash/mytheme/1024x768.cfg |
bgcolor=0 |
The above theme gives the progressbar a 3-pixel border by the use of 4 rectangles:
- top edge:
- progressbar(x0) - 3, progressbar(y0) - 3
- to progressbar(x1) + 3, progressbar(y0)
- progressbar(x0) - 3, progressbar(y0) - 3
- left edge:
- progressbar(x0) - 3, progressbar(y0) - 3
- to progressbar(x0), progressbar(y1) + 3
- progressbar(x0) - 3, progressbar(y0) - 3
- bottom edge:
- progressbar(x0) - 3, progressbar(y1)
- to progressbar(x1) + 3, progressbar(y1) + 3
- progressbar(x0) - 3, progressbar(y1)
- right edge:
- progressbar(x1), progressbar(y0) - 3
- to progressbar(x1) + 3, progressbar(y1) + 3
- progressbar(x1), progressbar(y0) - 3
Where:
- progressbar(x0), progressbar(y0) is the upper left corner of the progressbar.
- progressbar(x1), progressbar(y1) is the lower right corner of the progressbar.
If working this out melts your brain as badly as it does mine, then I suggest you get a pen & a sheet of paper. I'm sure there are a few Gentoo geeks out there who can do this maths in their heads, but the rest of us'll have to plan it all out a few times on A4 & expect to make a few corrections in red ink. A good way to debug would be to comment out one line at a time & see which edge is affected.
Conclusion
I hope you find this article useful and that it encourages you to design you own themes. Please update the wiki if you find errors or discover a new way to do cool stuff with gensplash (http://dev.gentoo.org/~spock/projects/gensplash/) - I notice I haven't covered colour gradients at all. They are supported, so please feel free to experiment with them.
I haven't posted to the wiki the original artwork I used for this theme, because I'm not clear on the ownership of all its components - you can probably get a copy of it somewhere.
What would be really nice is a piece of Free artwork to go with this article - if you have one for which you own the copyright, please feel free to make it available & edit the article to accommodate it, but I'd be grateful if you'd be prepared to take on the full article & make the layout of the .cfg file fully-compatible with your artwork.
Contributors
- Spock (http://dev.gentoo.org/~spock/index.php) for writing Gensplash (http://dev.gentoo.org/~spock/projects/gensplash/)! Thanks!
- Andreoni.com, original artists of the Lamborghini & its logo on the pictures, Tux the penguin & the Gentoo G.
- _mikec_ - from postings on the Gentoo Forums which inspired this HOWTO and for his work on the "GentooHorns" collage.
- Joe Stroller - original article, written in a single 8-hour session. I spent the last 3 days building a splashscreen and wishing there was a HOWTO on it. When I saw postings on the Gentoo Forums with problems I had to address them. I don't anticipate maintaining or updating this article, so please volunteer!