Pegon 

While relaxing after the hard-working period that was the GSoC, I came across a comment left by Torsten Rahn of the marble team. He wondered whether it would be possible to adapt image warping functionality so that it can be used to morph some old maps. Read More

Though this entry will be the last one about my GSoC, it certainly won't be the last one about my work on Krita or even on its new Transformation Tool. It was a great summer, I had a lot of fun working on this project. It was all the more stimulating so as I could follow the progress of the other GSoC students working for Krita. Everyone did such an incredible job, it gave me the envy and the energy to complete my project and make it as it is. Read More

I spent the past 10 days working on image warping. It wasn't easy, but I think most of the work is done ! Since I had absolutely no idea concerning the algorithm, and wasn't even sure what I wanted to do - I only knew I wanted to add an "image deformation" functionality to the tool -, I began searching randomly on the web. I eventually came across a nice paper entitled Image Deformation Using Moving Least Square. Apart from the snappy pictures at the top of the front page, what I liked was that it gave implementation details and put the emphasis on the speed of this method. Basically, it describes 3 different math functions (affine, similitude, and moving least squares) which distort an image according to the modifications made on a set of points. Read More

It's been two weeks since my last blog entry, so I thought it was time I gave an update about my work. The next step was to add perspective transformation to the tool, and the least I can say is it wasn't easy. First thing is it took me some time to find the formulas and good values to create a good perspective effect, and then to obtain the same one with Qt. There are different reasons why I had to know the formulas and couldn't just rely on Qt, one of them is that the perspective transformation is not invertible, unless you know the equation of the plane in which were all the points before the perspective projection. Read More

Hello everyone ! Last week I finally decided to spend some time on the UI of the tool, and you will see on this screencast that there has been some changes ! Read More

Hi guys, Maybe it's a bit late to talk about what I did last week, but anyway : After fixing some bugs in the transformation tool, I decided to add the possibility for the user to change the center of rotation. It was a bit tricky, because I wanted to express this rotation (around the current center) as a composition of a rotation around the original center of the selection and a translation (which is possible). Consequently, a succession of rotations around different center can be reduced to only 1 rotation around the original center and 1 translation. I used complex numbers for the calculation (quite convenient for 2D transformations), and I was pleased to see that complex numbers were standard C++ objects. Read More

This is my first blog entry about my GSoC project for Krita. Because i was busy doing a school project until June 11, i actually began working on the transformation tool last week. The aim was to rewrite most parts of the old transformation tools, in order to continue the project on a solid base, and with my own code, to make the job easier. I also wanted to make the tool perform transformations in real time, not just when the user releases the mouse button. Read More