Anecdote

I was inspired by a post over at the BlenderArtists forum about matte painting, to give camera mapping (a technique employed in the modern matte painter’s toolbox) a try. I remember a while ago following this tutorial, but it was very “hacky” and complicated, now there is a much easier/simplified way of doing it.

I partially followed this tutorial over at the Blender Wiki, but I decided I wanted to try something more organic, and found this picture:

The first thing to do, was to isolate the foreground hill in the image, by cutting out the original reference image in GIMP:

Then I roughly modelled the hill in Blender, before using a “UVProject” modifier, which (as the name implies) projects the isolated image onto the 3D geometry.

The next thing to do was to prepare the background. Using the clone tool in GIMP, I repainted the parts of the background that the foreground hill were covering to produce a background image.

Admittedly the cloning was a bit rushed, so it’s not a very good result!

Anyway, all I needed to do now was to map this image to a plane (for even more realistic results, I could have roughly modelled the background mountain, and made a second projection), and make a simple camera move.

The result was quite good, but just to had some of the errors in my model, and to add “real-world” camera properties, I also added some motion blur (or Vector Blur, as it’s called in blender).

OK, so after all that, here’s the result:

Camera Mapping Test (AVI, h264)

Camera Mapping test from Joel Davies on Vimeo.

I’ve finally completed the “architectural modelling” tutorial, and come up with the following render:

I composited it with a background image I got from Flickr.com… It’s hard to tell but the image is actually stretched in the render - I only just noticed it now!! I’ll be posting another render soon without the stretched background… I might try and add an entrance to the building if I have time.

There is a possibility that I might try and recreate the “Saying goodbye to an empty train” cartoon in 3D - it would be quite a challenge, but also would help me to learn more Blender!!!

Just a quick doodle type of thing I did t’other day, I think it’s pretty cool:

I’m rendering a 141 frame (5.64s) fluid simulation at the moment - it’s taking aaaaaaaaaaaaaaaaaaages!! On average it’s taking like 4 minutes per frame! Anyway I’ll probably post that up by tommorow.

As I mentioned before I’ve been trying to get this optical flow effect to work in Blender using the displace composite node. I tried it out on some real ‘live action’ footage (as opposed to the cube I used before). It didn’t really work that well - mainly because the shot contained some very dark spots where you couldn’t really make the effect out. Also I think the clip was too short, so you barely noticed the effect at all. I think I might try and make it work by looping some fire footage and duplicating it a lot of times. Another possibility is to use a development version of Blender, which has enhanced particle effect features (see the progress here), to use a technique called billboards, which means that you use particles to control a certain video, which in this case would be the looping fire footage. This would mean that I could have a controlled randomness to the fire footage. Unfortunately I’m having trouble getting the billboards to work without crashing Blender! Anyway, hopefully I should have a nice optical flow effect to show by… the end of the year!

Finally the end of exam-idge!

Just saw this ace effect on the extras of the LotR extended edition DVD, called Optical Flow. Basically you use the brightness values of a greyscale video/image as a basis to displace another video or image. For example in LotR, the scenes where Frodo puts on the Ring, and the whole world changes into this weird wispy kind of effect. To achieve this they would have used a video of some fire, converted it to greyscale and then used its brightness values to displace the video of Frodo’s view of the world. It’s also a bit more complicated - they use some kind of technique called particle billboard or something, where a particle system is used to drive the video of fire.

OK! So now that I’ve successfully confused you, here’s a video I made of what I mean:

Click here to view (120Kb, Quicktime MOV)

Right, so now you know what I’m on about, you may be wondering how I did it, ey?

Blender! Using the Displace node (coded by Matt Ebb - cheers!), I realised that this optical flow type effect could ACTUALLY be done in Blender!! Here’s a screenshot of my node setup:

For the video I used some free fire footage, from the good folks at detonationfilms. Basically I fed the fire footage into the “Vector” input of the Displace node, and just used a simple rendering of a cube as the image to be displaced. Also an interesting way of checking what the displace node is doing, is generating a “UV test grid” and applying the displacement to that:

Anyway, now that I’ve got more time I’m hoping to get this effect to work to the same extent that they used it in LotR - should be a good challenge!

Another thing… I was a bit bored of revising the other week and so I decided to write a script inspired by the “Look Around You” series. Basically its a spoof of all those cheesy old education videos (like Physics in Action!), called “Look to the Future”. Anyway I though I might as well upload it:

Click here to view (PDF, 7Kb).

Oh yeh, I forgot to mention the most obvious piece of news! NEW THEME!!

Hopefully I’m gonna finish making those 2 music videos I mentioned before as well!

Just recently did this test using Blender to composite a fire (from Detonation Films, who make fire & explosion stock footage freely available - thank you!) into this still I have from a short film I’m making. To make it more interesting, I partially “hid” the fire behind one of the foreground hills/ledges. Anyway, here it is:

Right click, Save As… to download (307Kb, MP4)