Fixes several files incorrectly stated a different license from the actual project, as well as the copyright headers included in all files. This change has no effect on the licensing terms, it should clear up a bit of confusion by contributors. Plus the files get a bit smaller, and we have less duplicated information across the entire project.
Overall the project is GPLv2 if not built with Qt, and GPLv3 if it is built with Qt. There are no parts licensed under a different license, all have been adapted from other compatible licenses into GPLv2 or GPLv3.
While the previous method worked, it matches no other implementation including a reference implementation. The new implementation almost perfectly matches the reference implementation and uses oversampling to achieve the goal. This has the downside of limiting the blur size to just 64, but it is necessary in order to achieve correct results.
Fixes#573
Dual Filtering (or Dual Kawase) is an approximation of Gaussian Blur that can reach much higher Blur sizes at a much lower cost. However it is locked to a 2^n size, which means that currently it isn't possible to use it for blur sizes like 19, 24 and 31.
The Blur works by using the linear sampling of a GPU, combined with down- and upsampling and carefully placed sampling points. This means that there is no need for a linear optimized version of this Blur.
Related: #45, #6
While Gaussian Blur is not a Blur type that really benefits much from linear sampling, it can be used for a slight quality and gpu usage reduction. However for Area and Directional Blur there is a better alternative: Dual Filtering Blur. And as with all other currently implement Linear versions of Blur, only Area and Directional Blur are supported.
This type of Gaussian Blur also has the loading hitch that exists in normal Gaussian Blur.
Related: #45, #6
Gaussian Blur is another Blur that now supports the new system, increasing the maxium Blur size to 128 and adding support for Rotational and Zoom blur. Various optimizations were done to the actual shader code which further reduced the GPU usage.
Currently the Gaussian curve is recalculated when the blur is first created, which can lead to a short hitch due to it having to search for the correct kernels. This is currently unavoidable and expected behavior until a better solution is found.
Related: #45, #6
Box Blur is a prime candidate for Linear optimizations, and as such reducing the total necessary samples by about half. However due to the reduction in samples, only Area and Directional Blur are supported.
Related: #45, #6
Box Blur is the first to be on the new system and has received all the new features and optimizations available. The maximum Blur size has been increased to 128, Rotational and Zoom Blur are supported and a small optimization has been done to the shader.
Related: #45, #6
