Tutorials

Down with tri’s – long live quads – close in work on my Blender spaceship model

After a long night watching pretty much all of Mad Men 3 back-to-back on DVD it’s once more to the spaceship model for more mesh tweaking. It’s time to turn all those tri’s peppered over my model like a pox into beautiful even quads – without compromising the complex mesh of this Vega Strike game spaceship.

Eliminating tri clumps on my spaceship mesh

The Vega Strike game engine won't like these triangles

But first some procrastination. What does Google say about the fine art of losing tri’s in Blender.

As usual the first hit I found giving advice about Blender issues was a post on BlenderArtists.org. It contains a couple of useful hints on how to kill tri’s. I also found a general discussion on Blender Newbies. It blames the subsurf modifier for the need to get rid of tri’s, and my spaceship is intended to have subsurf. This other Blender Newbies thread has a cool tip for slightly modifying tri’s that won’t convert into quads. You change their mind with the smooth command. Cool but too destructive my finely tuned spaceship model. OK enough of that. On with the job.

new quad, Blender

now one quad has replaced the two tri's

Two tri’s right next to each other was an easy win. I simply highlighted them with face select in edit mode and pressed ctrl J. Now as you can see above my spaceship has a quad that looks a bit like a necktie instead of those original tri’s circled in red in the first image in this post.

I hoped they were all going to be this easy – but…

I had two triangles at the mirror seam which refused to play nice and turn into a quad. I tried pressing ctrl j, I tried pressing F – and nothing. They just sat there.

So I deleted them and it turns out there was no edge at the mirror axis. I solved this little problem by selecting the two “hanging” vertexes and pressing f to draw a line. Then I switched to edge select and selected the four sides of my new four sided hole in the mesh. I then simply pressed f, and a quad was born.

No triangle could resist the power of my logical and spatial mind.

I did have to chase some triangles all the way to the mirror edge of the model on the central axis before I could merge two vertexes and finally get them to disappear, but even the most obstinate triangles could finally be squeezed out of existence at the mirror seam – leaving hopefully a spaceship model that will behave well and not throw up too many shading artifacts once it is in game.

OK, on to the next job in getting this model ready for baking.

Recalculating normals, marking seams, evening teselation, turning tris to quads etc on my spaceship model with Blender

Flipped normals on a Blender spaceship mesh

The ugly black hole made by flipped normals

http://starbrightillustrations.com/blog/wp-content/uploads/2010/04/Screenshot.png

Instead of posting about it i should probably be getting on with it, but what I’m doing is painstakingly – and over a period of days – tidying up my spaceship mesh in Blender.

This spaceship is intended to eventually be the Franklin, a unit used in the Vega Strike, open source space trading, combat and exploration game. I’m following a lot of advice I’ve been getting at the Vega Strike forums and step by step bringing this model to the point it needs to be to be added in game as a unit.

Lots of detail to be seamed and sharpened

Lots of detail, this might take some time

http://starbrightillustrations.com/blog/wp-content/uploads/2010/04/17_franklin_render_back2.jpeg

All this detail in the image here needs to be sharpened as explained in this Vega Strike forums post written by Chuck Starchaser. I’m beginning to wish I had added these seams before duplicating four guns for the wing hard points and attaching them. Oh well.

creases and sharp edges on mesh blender

Hard to forget which edges are done

http://starbrightillustrations.com/blog/wp-content/uploads/2010/04/Screenshot_wing_edge.png

Once the edge is marked as a seam and sharp it glows a bright radioactive orange in the default Blender theme. I was worried that I would forget which seams were marked. it turns out that i was worrying over nothing.

mesh tricky bit

A tricky bit

It’s not all plain sailing though. There are quite a few tricky seams to mark, like this one which is a circle with a bit hollowed out of it. it’s hidden away under the spaceship’s wing and buried underneath a pipe. I’m not sure how often it’ll even be noticed in the game, but I guess if a thing is worth doing then it’s worth doing right.

Once my mesh was looking a bit better I added the subsur fmodifyer as suggested, but it tore a bit of a hole in the nose of my spaceship model.

Now why on earth did it do that?

nice smooth spaceship

smooth

http://starbrightillustrations.com/blog/wp-content/uploads/2010/04/franklin_render_action_with_subsurf1.jpeg

I moved some edges of the mesh around and managed to get rid of most of the holes. So here are the latest renders.

latest render franklyn blender

the spaceship nose is all mended

http://starbrightillustrations.com/blog/wp-content/uploads/2010/04/franklin_render_action_with_subsurf2.jpeg

spaceship engines

http://starbrightillustrations.com/blog/wp-content/uploads/2010/04/franklin_render_back_with_subsurf2.jpeg

side shot spaceship spotlight render

http://starbrightillustrations.com/blog/wp-content/uploads/2010/04/franklin_render_side_with_subsurf2.jpeg

electric blue spaceship top

http://starbrightillustrations.com/blog/wp-content/uploads/2010/04/franklin_render_top_with_subsurf2.jpeg

spaceshipoverflies in dark void

http://starbrightillustrations.com/blog/wp-content/uploads/2010/04/franklin_render_under_with_subsurf2.jpeg

It’s interesting seeing this spaceship model evolve step by step through the various 3D Blender processes toward completion, isn’t it? Hopefully you’ll be able to follow the progress all the way to it’s eventual appearance in the game.

Here’s the blend file. it’s getting quite big with all these quads (and some tris still).

http://www.starbrightillustrations.com/blends/franklin_wip10.blend

Tips for making a professional spaceship mesh for games gratefully received

Spaceship render

There’s been progress on the spaceship mesh. It might not look like much, but a lot has been going on underneath. I have alerted the community at the Vega Strike forums about my intentions of doing 3D stuff, and have received a cautiously welcoming reception, and a lot of good advice. You can read the tips for spaceship modeling I was given in the second post of this forum.

I am really into the idea of getting some professional grade 3D stuff done for Vega Strike, even if it doesn’t turn out to be my own spaceship designs, and I have already started incorporating their advice into the model I’m making.

To summarise what I think they are saying;-

Point one would be that I should stop worrying about how many polygons the model is made up of. Apparently the sky is the limit, numbers like 150,000 being bandied about for a space station. This is a great relief. I’m sure I had read that the number of polygons had to be kept down, but apparently this relates to old technology and I’m probably showing my age by even mentioning it.

I think the number of polygons has already doubled in my mesh.

Point two is that as many polygons should be rectangular as possible. If possible, every polygon on the model should be a quad. My model had a lot of triangles, but I immediately started turning them into quads. It’s not that tricky, and once you know that this stricture exists it shouldn’t be too much trouble to keep to it. Here we start with two triangles, ready to cause all sorts of problems in the rendering process.

Mesh detail Blender spaceship

Now they have been deleted and a nice new rectangle is sitting where they once were.

Alterations to Blender mesh

So Like I said, it might not look like much has changed in this render of the spaceship, but a lot is going on beneath the skin.

Another fine spaceship image made with Blender and GIMP

I’ve been modeling spaceships in 3D again, to add to the huge gallery of spaceship art here at Starbright.

It’s not just about expanding the gallery though, playing around with the capabilities of Blender and GIMP is also a lot of fun. I’m working in a style right now that takes advantage of the 3D capabilities of Blender, but then has a lot of work done in GIMP to produce a 3D image that looks like an illustration.

In the illustration above the planet in the foreground has had a lot of GIMP work done on it and looks very painterly, and the planet in the background is straight out of Blender. It has that shiny chrome appearance of a render. It’s going to be the very next element to get a working over as I take this image towards being a completed illustration.

I’m also working on floor plans to go with the spaceship illustration – I know how everyone loves them. I suddenly realised that if I did a screen grab of the top view window in Blender and chose wire mesh as the view option I would have a nice technical drawing of my spaceship without having to do much extra work. So floor plans coming soon, but in the mean time what has been happening with the illustration, well…


Last time we saw the spaceship illustration it looked like this. Just a mesh with the default skin, and not a very complex mesh either, but it is already beginning to suggest the completed spaceship. It’s a simple cube cut in half and mirrored with a few simple transformations; subdivide, extrude and grab.


After just a few more extrude operations the spaceship mesh starts to look much more real. I’ve also changed the colour of the skin that the mesh receives when it is rendered.


Another bump extruded and scaled has been added here to be the cockpit. I’m now very happy with the camera angle and I haven’t fiddled with it for a while, I am still fiddling with the lighting though. I want it a little more dramatic so I added a second light source to brighten up the foreground edges of the spaceship.


More and more detail and complexity being added to the mesh. Even though there is a lot of complexity, it has almost exclusively been achieved by simply extruding and grabbing surfaces I also added a cylinder right at the front of the spaceship.


It’s a tiny detail, but like a cherry on a cake it makes all the difference. I had to join it to the original spaceship mesh to get it to mirror properly. With that little touch I was finished with Blender and it was time to move on to GIMP.


I rendered a nice big jpeg of the finished mesh and dropped it into GIMP. Because I chose a jpeg as the format I had a lot of white background to get rid of, but cutting out a spaceship with hard straight edges is no problem in GIMP. I just held down shift as I used the eraser and GIMP kept my lines nice and straight.


Once I had my spaceship cut out I started to add some details to it. Abstract spaceship details are called greebles in the business and you need to add an awful lot of them before the spaceship starts to look good.

This spaceship has only a light dusting of greebles – an airlock and some windows – it’s going to need a few more.

I also went back to Blender to make a couple of planets – just spheres set smooth with textures chosen from the presets that come with Blender. The foreground planet uses “random noise” and the background planet has the “marble” texture applied.

I’ve made a good start with this image and I have high hopes that it’s going to be my most professional looking spaceship illustration yet, when I eventually get it done.

GIMP step by step Moby-Dick tutorial more detail

After a quick pause to post my entry for Illustration Friday it’s back to the Moby-Dick painting. I quickly added some spume to the big wave at the centre of the painting and then was about to turn to the whaling boat, when I realised that I don’t really know what a whaling boat looks like.

Thank goodness that all us artists have Google now. To find a nice boat to use as reference I simply had to do a quick Google search. I did the same to remind myself what a whale looks like and to find out what made Moby white. It makes the whole illustration process a lot easier. Here is the page where I found a nice detailed view of the inside of the craft. It’s actually a website for people who build model boats and has a lot more detail in sharper focus than I was able to find anywhere else.


I’m just going to be using it for reference, and I’m pretty comfortable that finding a picture of a boat to use in painting my illustration isn’t cheating. Here I’ve dropped the picture I got from the internet into the GIMP xcf file to make sure I can do it justice.

With the boat in place, and a few alterations made to turn it around to face the danger coming from the background of the illustration, it was time to add some detail to the figures in the boat. At the moment they still look like the match-stick men of an L.S. Lowry painting.

As I’m not entirely sure what the 18 th century adventurers I want to put in the picture might look like It’s back to Google.

I found a great bunch of whalers to use as reference. I found them on a blog post where the blogger was boasting of his friend’s performance in the Alaskan Whaler category of the World Beard and Moustache Competition. Based on this photo, I guess the most important accessory to give my crew is an Aron jumper.


I got distracted after working on Ahab for a while and did some work on the eye of the monster whale. I added detail and got it to pop out of the image a bit more. Then I sketched some white lines on the whale.

I did this to give the impression of sheets of water floating down the monster’s hide as it emerges from the depths. To help sell these white squiggles as sheets of water I used the smudge tool to smear them a bit. It’s quite a nice effect.


The picture is really starting to take shape now. Next I decided that the wave needed a bit of detail too. So, going about adding detail to the image in exactly the same way as the stage before, I just drew some lines on the wave in the same colour as the wave’s brightest point.


Then to sell these little touches as natural I used GIMP’s smudge tool to make them a little more complex and smoky looking. I think it looks quite good and gives a good impression as a boat wake.


So now I’m going to keep on adding more and more detail in exactly the same way, until of course I suddenly decide that this illustration is done. I have a feeling that won’t be for a while yet though, I think this image is good for at least another couple of blog posts.

paint ebook cover image with GIMP, tutorial pt 2

Here is stage two of the illustration that will eventually be the book-cover image, you can see stage one, the initial sketch, in the original post. The main subject of the illustration is really starting to take shape, but a lot of work still needs to go into Ahab and his crew.

To start turning my scan of my initial sketch into an illustration I opened gimp and made a new document of the dimensions I wanted. Then I just dragged and dropped the jpeg image of the scan into the new gimp document. I then resized it to cover the whole image and I was ready to go, time to plug the graphics tablet into the USB port. On top of the scan of the initial illustration I added four or five large areas of colour to the image.


The whale is one solid block of colour on a separate layer, and so is the wave, boat, flippers etc. You can see the first few layers of the image in the screen grab below, but of course I’ll be creating an awful lot more layers than these few. The more layers you have the more control over your picture you have.


You can see that I have switched some of the layers off in the image above (the eye icons are gone). I did so that I could work on other elements without the whale for example getting in the way.


Just a few more details have been added here. You can see the clouds have been painted very roughly into the background and I’ve just started to make them more cloudy with the smudge tool. I’ve also given ol’ Moby some teeth.


The distinctive white colour of the mythical beast from this illustration comes from barnacles. I did a bit of research and it turns out that our creature from the depths was not an albino. This image is right at the start of the process of adding this colouration.


After twenty minutes of repeatedly jabbing the graphics tablet with the stylus the look of the main character is starting to take shape. It still looks a little like the measles though so I’m not going to be able to close GIMP for the day just yet.


I added a big shadow on top of the layer of the illustration with the colouration and then finally added a layer of patchy white underneath that layer to produce first a bumpy but imposing effect and then a much smoother and more frightening creature. The star of the this book, although most people probably read Moby-Dick as an ebook these days, and there’s no reason why an illustration like this cant be its digital cover.

digital GIMP art image with a graphics tablet

Today I am painting a scene that is inspired by the word rescue*. Actually I started painting the scene yesterday, and there might still be some little touches to add to the illustration before it’s done, but enough of that – back to work.

Rescue of course requires a dangerous situation and someone in danger, and naturally someone to get them out of it. In my illustration I decided that the brave heroic figure of the image would be a lion, and the creature in danger would be a monkey. I later changed my mind and decided that the foreground figure of the picture would be an elephant instead. But that’s the beauty of GIMP, or any other image manipulation software that you might like (I know you are all thinking it so I’ll just say it, some poor misguided people even use Photoshop for this sort of thing, no matter the price and the bloat). Whatever application you use, if you put each element of the image on a different layer you can just delete the layer and replace it with very little trouble – replacing your monkey with an elephant for example.

Here is the original sketch for this illustration, and as always I didn’t do any preliminary sketches or look for any reference material, I just jammed my graphics tablet into the USB port fired up GIMP and got going. The composition of the illustration was a little tricky but once I had put the boat on a nice big wave in the background there was plenty of room in the foreground of the image for action.

As you can see in the above screen grab I try not to touch the background and so I put every different element of an illustration on a separate layer. Here the sketch is on a transparent layer – denoted by grey checks – hovering above the background layer.


The next step is a simple and fun series of colouring in. The layers with the different colours on are all separate, and if each layer is put below the layer with the sketch on it’s a lot harder to go over the lines.


Next come the stage where I add detail by overlaying layer after layer of semitransparent black over the bare colours and moving them about and mixing them with the smudge tool. Then I sample the original colour and lighten it a bit by selecting the foreground colour at the bottom of the tool box. I paint this on top at full opacity – on it’s own layer of course, you can never have too many layers – and you have highlights.


The monkey looked too much like a badly drawn human so it had to go, but what to replace it with. I decided that an elephant would be quite funny, because there is no way that the skinny lion in the boat is going to be strong enough to pull the elephant out of the water, even if the boat was big enough for it to sit in without it sinking.

The elephant gets a little more detail with the trusty layers of black and smudge then highlight method I mentioned earlier and the image is getting a lot closer to being a completed digital painting.

*as usual my inspiration word came from Illustration Friday, and I’ll be posting the illustration there as soon as it’s done.

Vampire Cat illustration, with GIMP step-by-step tutorial

Vampire Cat Illustration

Yum! Packed Lunch!

Although I am far from finished with my troublesome Pixie Catcher fantasy illustration, I’m going to put it on hold for a day because it is Illustration Friday time again. As regular readers of this blog will know – and yes this blog does seem to have regular readers – Illustration Friday is what is known as an art challenge website . This means that every week they post a word, and the online artistic community (i.e. everybody) is invited to create an illustration based on that word. This week’s word is “ expired”.

Probably inspired by the famous Monty Python Dead Parrot Sketch

Mr. Praline: ‘E’s not pinin’! ‘E’s passed on! This parrot is no more! He has ceased to be! ‘E’s expired and gone to meet ‘is maker! ‘E’s a stiff! Bereft of life, ‘e rests in peace! If you hadn’t nailed ‘im to the perch ‘e’d be pushing up daisies! ‘Is metabolic processes are now ‘istory! ‘E’s off the twig! ‘E’s kicked the bucket, ‘e’s shuffled off ‘is mortal coil, run down the curtain and joined the bleedin’ choir invisible!! THIS IS AN EX-PARROT!!

( more about the sketch on Wikipedia)

… the word expired is associated with the death of small animals in my mind, and my first ideas for illustrations were to do with zombie parrots and hamsters.

But then inspiration struck and I thought, “Why not a Vampire cute little animal!”

Why not indeed, technically vampires are the undead rather than expired, but I think the idea still holds.

So I fired up GIMP (as you probably know, GIMP is the leading open-source competitor to Photoshop) and attached my trusty graphics tablet to one of the USB ports on my lappy.

My first sketch was as usual a little off composition-wise, but that was easy to fix because I had done the sketch on a transparent layer that I added above the background white layer of the image. I simply increased the size of the layer of the sketch until the central part of the image, with the cat, was all that was left showing.

Now the cat is undoubtedly the focus of the image, as competing elements such as the coffin in the foreground have been forced off the edge. I created a second transparent layer and coloured in the cat.

I also coloured in all the other elements of the illustration in the same rough and ready way, using the sketch as a guide and putting each new element on a separate layer. For example the cat’s body, collar, tag, eyes and teeth all get their own layer. With my graphics tablet and the GIMP brush set to a wide radius this is the work of just a few seconds.

When this process of colouring is far enough along it is possible to just delete the layer of the image file with the sketch on, because it isn’t needed any more.

Because the image is an illustration of a vampire it is almost inevitably a night time picture. To make a nice night sky I have put silhouettes of trees on one layer, a blend from orange to invisible on a layer behind that, then a moon, then a duplicate of the moon on a new layer smudged and with the opacity turned down to make it shine, then behind that a layer with stars and behind that a layer of solid dark blue.

Then to add more character to my character I added a new layer to paint shadows onto the cat, and yet another layer to give it eyelids. As the image is becoming more finished I also dropped the png file I have of my signature into GIMP by dragging and dropping, GIMP then did all the hard work of importing it into the image on a separate layer for me, yippee!


Now where into the phase of adding detail and tidying up. Here I have added some bumpiness to the soil, and I’ve tidied up the lower edges of the grave stones in the background of the illustration. This process of tidying up and adding detail to the image could potentially go on for a long, long time, and it really is a matter of taste as to where you draw the line and say, “ This is a finished illustration!”

I hope you like the Vampire Cat.

Digital Fantasy Painting with pixies using gimp

I’m working on another digital painting right now, as usual, with GIMP and my Wacom Bamboo graphics tablet. I have spent a couple of evenings on it, something like eight hours in all, and it looks about half done to me. I am still trying desperately to take my images in a cuter direction, and so I decided to paint an image with pixies in it. It is going to be called The Pixie Catcher when it is finally done.

For people who were not brought up in the UK being read Enid Blyton stories at bed time, a pixie is a fairy like creature, sometimes thought of as being blue. Here is what Wikipedia has to say about pixies.

All I have decided about the pixies in my illustration so far is that they are blue and have wings and a tail. I’ll be adding more detail to them as work on the illustration progresses.

I started work with the largest and most important character in this cute fantasy illustration, the pixie catcher himself. I simply opened GIMP and created a new image (I chose to make it an .xcf file to be able to use all GIMP’s features and save drafts). Then I immediately created a new layer within the image to sketch on, I prefer sketching on a transparent layer, rather than the white background because then I can colour in underneath the sketch more easily. I like to sketch freehand with no reference material, like photographs or thumbnails, because the image always seems more spontaneous and real to me when little or no planning has gone into it. It does mean that I sometimes have some problems to solve as I go on though, but that just adds to the fun.

I liked the way the sketch was going and added more and more detail to the character, adding pointy ears to make him look more like a fantasy creature.

Next I turned my attention to imagining the sort of fantasy world where this image might be set. I have been imagining a fantasy world which might end up being called Spiral Land. There would of course be a lot of spirals and, as you can see here, even the branches of the trees might be more spiraly than usual. I have turned the layer with the main character off, by clicking on the eye icon, so that I can concentrate on the background.

As you can see in this screen shot of the GIMP interface that in the layers window only the forest sketch and the background are enabled with the eye icon.

I then switched the layer with the main character back on and created a new layer below it to add some colour to him.

I then added a couple of pixies flying away from the main character as fast as their wings can carry them. To make the image cuter I had the idea that the trees would be helping the fairies to escape, so I altered the image to have one of the branches curling around the main character’s hat to try to stop him. It’s quite a subtle change, and I might have to add more branches helping the pixies to make this idea more obvious.

Here I have started to add some shadows to the image, you can see the change best on the character’s face. Shadows are really easy to add in GIMP, and they really bring the image to life. Simply create a new layer above the thing you want to add shadows to. Paint the shadows roughly in a dark colour, but turn down the opacity of the layer, using the slider at the top of the layer window. The lines and areas you paint will transform from solid colour to the merest hint of a shadow at low opacity, or quite heavy shadows at high opacity. You can make the edges of the shadows less sharp with the smudge tool, and when you are happy with the effect just right click on the shadow layer and chose the merge down option to add the shadows to your object.

Apart from a few edits like changing the shape of the hat, adding spirals to the main character’s collar and resizing the image to zoom in more on the scene the only difference between this image and the one before is layer after layer of shadows and a lot of time. Although I have also switched off and deleted the layers with the original sketches on because I don’t really need them any more. Now I’m more painting than drawing, but still using the same GIMP tools and my graphics tablet, the best 60 euros I ever spent.

I’m starting to like this image and I’ll be doing more work on it soon. I’ll post the final image here on the blog as soon as it’s done.

GIMP Tutorial section gets a makeover

I’ve been working on the tutorials section – including GIMP, Photoshop, etc – at my Illustrations website. It’s going to be a great page when it’s done, with link after link to step-by-step tutorials telling how to paint and render all kinds of images, from sc-fi to children’s book.

But as I was editing it I noticed an ugly problem. When you look at the website on a computer with a wide screen, on an Apple Notebook for example, the title bar is stuck in the left corner and the dividing line below it extends on for an arbitrary number of pixels. It’s really quite untidy, and I’m going to have to fix it.

I’m using Kompozer to create the non-blog part of the site, with all the galleries and tutorials, and it is really quite limited, but I strongly hoped there would be a solution.

This tutorial on using Kompozer to create a site seemed to have the answer. Just put everything in a table that has the precisely attribute and is set to 100%. I quickly gave this a go.

And with a new page, following these instructions it would have been no problem, but this is the main page of my art portfolio website and I have been working on it for a year with more than one web editor, uploading illustrations, moving images and text around and doing a bit of direct poking about in the html as well.

It just wouldn’t work for me for a long time, and then I noticed that deep within the code of the page, its width was being defined. I deleted that line of code and almost everything started working. It only took an hour of trial and error too.

I say almost everything because there was still an annoying white border to the right of the site header. I couldn’t find any way to fix this using the Kompozer WYSIWYG interface, but when I edited the code to copy the same 0 margin value as at left and top, it finally started to look the way I wanted, a solid bar across the top of the screen.

So here is what the illustration site looks like now, oh and there are some nice illustrations to go with my hard won graphic design victory.