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icosahedron
03-17-2009, 01:41 PM
Not sure if this is in the right section, but I'd like some very, very simple advice please, this is my first day with Gimp and I have no prior drawing experience to speak of.

I thought since I'm playing with the Gimp to see what it does, I might as well practise with something I want, so I had a go at the throne I put in the requests section (I'm still looking for offers btw, I doubt if this will turn out to be any good.)


Since there is no alabaster in the patterns area and I have no idea how to import a texture even if I could find one, I went with default marble.

I started by opening the throne image I'd created in Word Draw. There's no way I could draw a complex assembly of geometric shapes like that in the Gimp yet awhile, then I figured out how to use the lasso select and selected each of the shapes in turn. The fill tool works like MSPaint, so that was no problem, and I got each face of the throne filled with marble texture.

Whilst I had each area selected (cos there's no way I'd be able to accurately re-select it once I'd let go) I put a drop shadow on some of the parts. I know that's probably the wrong technique and I did see something called perspective shadow, but I couldn't make Gimp see what the shape was supposed to be to lay the correct shadow down. The drop shadow seemed to do it sort of nearly right anyway.

Then finally I lassoed the whole shape and put a drop shadow round all of it.

General comments and helpful suggestions for simple improvements please (and how to carry them out) particularly:

Is is possible accurately to re-select something once you've let go of it? How?

How do I darken/lighten selections (eg to make two sides of the plinth shadowy)?

How do I put shadowing on the top of the backrest to make it look like there are points at the two ends and in the middle?

How could I take some text (say in a runic font) and make it appear like it's carved into the arms of the chair? I'll worry about perspective carvings in the backrest later, that's probably a whole lot more difficult.

How do I make it look older?

If these techniques are beyond the novice, just give me a general pointer in the right direction and I'll try to pick it up later.

Thanks.

RobA
03-17-2009, 02:35 PM
Is is possible accurately to re-select something once you've let go of it? How?

Yes. Use the Select > Save to Channel. This saves the selection as an "alpha mask" in the channels dialog. If you don't have that showing, you can with Windows > Dockable Dialogs >Channels (but I think it is in the default dock. It is the tab that looks like this:
11401

The arrow points to the button that lets you load up a saved selection.

If you intend to save many selections, I would suggest renaming them (double click on the "Selection Mask copy" text and give it a new name, like "Seat Selection"





How do I darken/lighten selections (eg to make two sides of the plinth shadowy)?


When you have a selection, thee are a number of ways to lighten and darken it. I would suggest starting with Colors > Brightness/Contrast.


No time for the others right now, sorry...

-Rob A>

icosahedron
03-17-2009, 06:47 PM
Thanks for that Rob.

I have another problem with the Gimp.

I've tried to save my throne as a png with a drop shadow around it. I can save the throne with a transparent background, but as soon as I try to put a drop shadow around it and save, I get this popup:


Your image should be exported before it can be saved as PNG for the following reasons:
PNG plug in can't handle layers

* Flatten image

* Merge visible layers


If I choose to flatten, the background becomes white instead of clear, and if I choose to merge, Viewingdale's PNG to VMI converter has a "runtime error" whatever one of those is, when I try later to convert the PNG.

I don't know why I get the popup at all, because I've previously saved images with a drop shadow and it just saved ok.

Any idea what's happening?

Cheers.

Redrobes
03-17-2009, 08:30 PM
Can you post me any file that consistently causes a runtime error. I was aware a long time ago that 16bit PNG's caused it to go bad but that was supposed to be fixed ages ago where it stripped off the bottom byte and made it 8bit instead. No image should cause it to crash. Anything that causes any of my apps to crash I wanna know about pronto !

If you can mail something can you just check the version number of the converter app and see if its V1.06 ? Maybe I screwed up the patcher and its not dishing out the latest one.

PNG is a file format with a number of styles but the main one is a colour set of red green and blue and the transparency amount called the Alpha so its known as RGBA. These come in 8 bits per pixel or very rarely 16 bits per pixel. But thats it. There are no layers saved with PNGs. If you merge the layers in Gimp and save out then it loses the layers in the file.

I wouldn't have expected Gimp to merge and save the file as a 16bit PNG but you never know...

Edit -- Tried many options all similar to that described and I cant get a crash. Could do with that specific file there.

jfrazierjr
03-17-2009, 08:42 PM
Thanks for that Rob.

I have another problem with the Gimp.

I've tried to save my throne as a png with a drop shadow around it. I can save the throne with a transparent background, but as soon as I try to put a drop shadow around it and save, I get this popup:



If I choose to flatten, the background becomes white instead of clear, and if I choose to merge, Viewingdale's PNG to VMI converter has a "runtime error" whatever one of those is, when I try later to convert the PNG.

I don't know why I get the popup at all, because I've previously saved images with a drop shadow and it just saved ok.

Any idea what's happening?

Cheers.

Make sure you have a layer selected and NOT one of your channels. I accidentally do this once in while and you just have to go back to the Layers tab and select a layer. NOW... first... don't save it as a png cause then you can't easily edit the layers which eliminates the entire power of GIMP. Save the file before ANY CHANGES as a native gimp file (.xcf). Then as you make changes with new layers (if needed, depending on what you are trying to do), you using the Save a Copy menu setting to "transform" a copy of the native gimp file to another format such as png or jpeg.

If you still have problems, if you would save it as a xcf file, zip, and attach to your post I can take a look at it based on your steps.

RobA
03-17-2009, 10:18 PM
I doodled this up in Inkscape -

It might have a better shape on the chair back for your needs.

11420

-Rob A>

icosahedron
03-18-2009, 07:34 AM
Thanks for the support guys, all useful info there. Bit of a bind that I need to store two copies of the drawings, one for Gimp and one for all other apps, especially as I'm just starting to realise how much space graphics storage can eat, but I can see the value of it.
I suppose I could just store in xcf and print pngs on demand...

I eventually managed to get the file to a suitable PNG by just poking about with it. Still not sure what I was doing, but it worked. Wish I'd got your replies about saving in native format before I closed down for the night, JF, but hey, it's just an experiment. Once I get used to the software, I could probably reproduce in a few minutes what it's just taken me several hours to create by trial and error. And I know for next time. :)

Redrobes, it wasn't what I'd call a crash, nothing locked up or trashed my work, it was more of a refusal to comply with a request. I'll PM you, but I think I've overwritten that file.

Right now, I don't even know the difference between a channel and a layer. I'll get there eventually. Surprisingly, Gimp hasn't scared me off yet, in fact I might be able to do most of the simple stuff I always wanted to do without too much learning. After that, it's all bonus.

I'll be happier when I get a windows copy of the help file. I'll email Gimp today and see where they've hidden it. It's a PITA to have to look things up online, on another computer, that might not even be powered up at the time. :(

Here's the current version, background is now properly transparent and I've cleaned up some of the ugly black lines with a bit of pixel-clicking. I might try rounding off a few corners next, though that's gonna make area selection almost impossible.

That seat-back looks great, Rob. See, no matter how good the software is, it's no substitute for talent - unfortunately for me.
Hmm. It shows up the fact that my seat back is too wide, it shouldn't overhang the plinth. Can't fix that without starting again from scratch, though.

Looks a bit tombstoneish at pres...

C&C anyone??

jfrazierjr
03-18-2009, 10:52 AM
Right now, I don't even know the difference between a channel and a layer. I'll get there eventually. Surprisingly, Gimp hasn't scared me off yet, in fact I might be able to do most of the simple stuff I always wanted to do without too much learning. After that, it's all bonus.


Lets do the simple one first. A channel is a special layer that is b/w only. Typically, it's used to make masks(come back to this one later by viewing my tutorial in my sig on layer masks.)

A layer is just what it sounds like. You draw stuff and as you draw stuff on higher layers, they overlap. This is exactly the type of thing used in animation (except images are not animated of course). So.. in your example below, I would probably break your chair up into component parts. The base would be the lowest layer, followed by the seat, then the arms and finally, the back as the highest layer. Generally, you would put drop-shadows on the lowest available layer of an image after you have created the whole thing. If you have ever seen any type of animation cells the old way, they will have several layers of clear plastic type stuff and draw different things on each of those plasticy layers and then put them together into a single "frame" to form one cell of an image. Layers in GIMP are pretty much the same.




I'll be happier when I get a windows copy of the help file. I'll email Gimp today and see where they've hidden it. It's a PITA to have to look things up online, on another computer, that might not even be powered up at the time. :(Do you have the latest version or an older version of GIMP?

http://gimp-win.sourceforge.net/old.html There is a link to several language specific helpfiles for an older "dot" release(only a few months old and no feature changes, just bug fixes, so should be up to to date)





Here's the current version, background is now properly transparent and I've cleaned up some of the ugly black lines with a bit of pixel-clicking.
C&C anyone??

Overall, I think you did a really good job!



I might try rounding off a few corners next, though that's gonna make area selection almost impossible. This is where building in layers makes a WORLD of difference in ease of editing later...

RobA
03-18-2009, 01:11 PM
Nice Work!

I picked up a few tips at the Dundjinni user art forum while making this type of object.

Here is a rework of your throne:
11445

The only difference is in the shadows. I reduced the overall outer shadow.

Keep it a bit closer to the object then you had. I lightened it at the back of the throne, cause higher objects tend to cast a less distinct shadow.

I added shadows across the seat font and arms to give more illusion of height above the base.

I shaded the left and right of the base slightly to define the corners to the front.

All of this was done with new layers (the extra shadows/shading) or layer masks (reducing the existing shadows) to make it effectively "non-destructive" on the original image.

And layers is what lets you do (more non-destructive) things like adding a solid dark violet layer in "grain extract" mode to get a variant like this:

11446

and my changing that colour layer you can create a whole plethora of different coloured thrones as needed.

Keep working at it! See, Gimp isn't that hard!

-Rob A>

Redrobes
03-18-2009, 04:28 PM
Redrobes, it wasn't what I'd call a crash, nothing locked up or trashed my work, it was more of a refusal to comply with a request. I'll PM you, but I think I've overwritten that file.
That was a crash. If you had been running a program like Gimp or Photoshop and had many hours of work painted and it did that then you would lose it unless it had some kind of autosave facility. Crashing apps are a pain. I got your image now so ill look into whats going on. I have used the converter extensively and have not seen it before so glad it happened at a non critical moment.

icosahedron
03-18-2009, 06:20 PM
Ok, thanks for that. I'm pretty much sold on layers. :)
I knew they were useful, but I'm beginning to see just HOW useful.

Doh! I hadn't realised the 'old' versions of Gimp were bug fixes and only a few months old. That'll be why there isn't an up-to-date help file. I'll go grab one of those 'old' helpfiles. I've installed the latest Gimp, it seems to run ok on W2K.

I might start the throne again from scratch and build it up in layers, saving in xcf and applying what I've learned. Then I can get rid of those 'wings' on the backrest and practise copying some of the shadow techniques you've shown me, and maybe pick up some other tips from the helpfiles as I go. I might even see if I can carve some runes on it.

What 'width' of shadows did you use, Rob? Mine were set at 50.

I tried adding a seat cushion to it today, but it turned out a bit 'floaty'. If I can put some shadow on top of it, it might look better. This is fun so far - taking up far too much time that I don't have, but fun nevertheless. :)

jfrazierjr
03-18-2009, 06:54 PM
Doh! I hadn't realised the 'old' versions of Gimp were bug fixes and only a few months old. That'll be why there isn't an up-to-date help file. I'll go grab one of those 'old' helpfiles. I've installed the latest Gimp, it seems to run ok on W2K.


Yep. x.y.z versioning format:


x is the major version which means some very large changes.
y is for some minor features (not that all users will think the are minor additions!).
z is generally for fixing bugs that are found that can't wait for a y release to be fixed.

Software producers have a WIDE range in timelines between releases, but you could expect GIMP to release y releases perhaps once a year and several z releases throughout the year.


Ok, thanks for that. I'm pretty much sold on layers. :)
I knew they were useful, but I'm beginning to see just HOW useful.

GREAT. now.. play for a few weeks and make sure to check out my layer MASK tutorial (channels are one way to make repeatable masks) and you will realize quickly just how much more useful it is when using layer masks opposed to layers alone(not for everything... sometimes it's overkill...) One of your goals should be trying to make non destructive alterations as much as possible. Layers (and eventually layer masks) will help with this a TON.

Also.. be sure to check out RobA's scripts for GIMP as well as several others floating around as they greatly simplify things (GURM!!!!!). There is also a really nice noise maker that is far better than the default one named Femilage... get it as soon as you realize you want/need to add some noise to an image.

Redrobes
03-18-2009, 09:34 PM
Robs scripts are great but they would require you to install Python and do some tweaking stuff to get them running. Id suggest moving onto those when your more comfortable with the app. The stuff Robs scripts do by nature are things that Gimp cant do easily which means that they are doing some pretty convoluted things.

RobA
03-18-2009, 10:06 PM
What 'width' of shadows did you use, Rob? Mine were set at 50.

:oops: I have to admit I didn't use the drop-shadow command. I just used the path tool to outline the area, turned it into a selection (there is a button in the path tool to do that), then filled it with a Foreground (black)->transparent gradient by eye (using the ctrl key to force the gradient tool orthagonal... that is a handy tip for most gimp actions... the control key forces things into 15 degree angle increments...)

-Rob A>

jfrazierjr
03-19-2009, 12:14 AM
Robs scripts are great but they would require you to install Python and do some tweaking stuff to get them running. Id suggest moving onto those when your more comfortable with the app. The stuff Robs scripts do by nature are things that Gimp cant do easily which means that they are doing some pretty convoluted things.

Actually, I think all of Rob's script's work out of the box since they are written scheme. But you are right, there are a few scripts (GURM is the big one for me) that require python and as you say, its a pain in the but to set up.

RobA
03-19-2009, 01:45 AM
jfrazierjr is correct. I've been playing with python, but have stuck with scheme as it is available on all platforms "out of the box".

-Rob A>

icosahedron
03-19-2009, 09:10 AM
Much of this is like a foreign language just now, but I'll pick it up in time. It gives me some pointers of what to look out for.

Thanks for the tips. :)

icosahedron
03-22-2009, 01:56 PM
Nice Work!

I picked up a few tips at the Dundjinni user art forum while making this type of object.

Here is a rework of your throne:
11445

The only difference is in the shadows. I reduced the overall outer shadow.

Keep it a bit closer to the object then you had. I lightened it at the back of the throne, cause higher objects tend to cast a less distinct shadow.

I added shadows across the seat font and arms to give more illusion of height above the base.

I shaded the left and right of the base slightly to define the corners to the front.

All of this was done with new layers (the extra shadows/shading) or layer masks (reducing the existing shadows) to make it effectively "non-destructive" on the original image.

-Rob A>


Rob, I've done a re-work from scratch on the throne, reducing the 'wing effect' of the back and trying to copy the effects you've shown me here, but I'm struggling to find how you got a shadow on the front of the seat and one side of the arms. I can get all sorts of weird shadow effects, but not a straight shadow along an edge. How is it done? The only thing I can think of is to do a standard drop shadow and then mask off 3 sides of it, but I haven't mastered masks yet and there's probably an easier way. :)
And I still haven't got the help file to load. :(
Cheers.

icosahedron
03-22-2009, 02:50 PM
Never mind, I found it. It's just a simple offset on the drop shadow. :)

Now I just need to read those mask tutorials to find out how to lessen a shadow.
Once I've got that bit done I'll repost the pic.

icosahedron
03-22-2009, 04:58 PM
Here we go.

I suppose I haven't put as many layers into this as I ought to for self-preservation, but I have the basic throne on one layer and each of the different shadows on new layers, so I'm getting there.

Having found how to do one-sided shadows, and having saved as an xcf this time, I've been able to play around with the shadows much more (I might still go back and lessen the shadows on the outside of the arms a bit) so it has helped a lot.

I read JF's mask tutorial and applied it to the top of the backrest. The 'face' of the backrest had a drop shadow on it which covered the top of the backrest, and I reduced this shadow by adding a slot shaped mask with a 50% grey slot and a 'marble layer'.

Of course, as I write this, I'm thinking 'idiot! why didn't you just remove the drop shadow and add a shadow to the lower edge only, now that you know how to do that?'

Ah, the benefit of hindsight! Still, it's given me some practice with adding channels and layer masks, and I can always go back and do it the right way later.

Anyway, I'm reasonably happy with this as a first Gimp project. It's given me the throne I wanted and I've learned some basic Gimp techniques along the way. I'll probably try adding some embellishments later, such as carved runes, but I think stage 1 is complete.

Thanks for the help on this, guys.

Just in case there's anyone out there who's even worse at drawing than me, you can use this on a CC by NC basis.

BTW, how does one go about rating a tutorial?

Redrobes
03-22-2009, 05:19 PM
You can rate a thread at the top bar.

I like the throne. Most people seem to put some dark halo around objects to give them a bit of lift off the floor - it seems to work pretty well. I have found that as the height of an object gets larger - i.e. arms of a monster as opposed to feet, then making the halo less pronounced and wider seems to give an even greater degree of feeling that its off the ground. Sometimes that's a bit hard to do tho.

So, if this CC with NC-BY-SA, would you like your throne to be a viewingdale download ? :)

icosahedron
03-23-2009, 07:09 AM
Ah, I see the rating thing now. I wasn't logged in before, so it didn't appear.

I put a small drop shadow or halo around it, (Gimp automates the process, I couldn't do it by hand) but I made it smaller and tighter following Rob's advice. It probably doesn't show up well on the brown background here. I haven't seen what it looks like in context yet.

If you think it's worthy as a download, I'd be honoured. :)