As i'm a student and i should be busy with writing some papers ... i'm spending waaaaaaay to much time derping around having crazy ideas. since they are forgotten quickly most of the time, i thought i share them with you.

this time: what D is missing for me

i'm coming from the field of computer vision and computer graphics. algorithms used in that field often utilize some heavy maths. like solving some heavy least squares equation systems, or graph algorithms.
because of that Matlab is often our tool of choice for quickly testing algorithms. After everything is running we translate things to c++.

Idea1: a general interface to describe n-dimensional matrices
i think the D syntax has the power to manipulate matrixes in a very expressive way. a great addition to the standard library would be to define a basic interface to work with matrices.

mat2d = DenseMatrix!float(5,5); // create a 5x5 float matrix
mat2d.zeros(); // initialize with zeros
mat2d[0..$, 2:3] = 1; // slice the matrix and fill the slice with ones

Specialized matrix types would then define the underlying memory layout and capabilities of a matrix. Like a matrix could be dense or sparse ( stored in the yale format or whatever other format ). depending on the needed operations the programmer would choose a fitting matrix implementation.

This would not only be useful to solve math problems. But also to define for example adjacency matrices for graphs, or to store images.

Idea2: Matrix Solvers
Have some base algorithms to solve linear and quadtratic systems on top of those matrices. (LU, QR, ...)

Idea3: Visualization
Imho D is lacking a good UI toolkit. I again like here the simplicity of matlab that lets me just pop up a window, and show a simple diagram or picture. Often its not necessary to create a sophisticated UI, but having a visual representation of data often helps with debugging and understanding of algorithms.

Some modern applications like Avast, Steam or Spotify create their user interfaces based on web technologies. Recently i've seen that somebody threw together a demo with libcef, which lets you use the chrome embedded framework, to basically have chrome in a little window.
http://dblog.aldacron.net/2015/01/derelictcef-binding-to-chromium-embedded-framework/
http://imgur.com/pYlP3dE

maybe that would be suitable to throw together a simple image viewer / diagram viewer. Based on some opensource web chart library ( like d3.js or whatever )



until now i didnt have yet the time and/or skill to realize those still very rough ideas. i hope you can give me some suggestions ...
... on what does already exist maybe in a similar form
... on what you would love to see to be realized of those ideas
... on why my ideas are garbage :'D destory pls

cheers :)

On Tuesday, 22 March 2016 at 14:08:55 UTC, _d0s_ wrote:
> Idea1: a general interface to describe n-dimensional matrices

Perhaps this is what you're looking for?

https://dlang.org/phobos/std_experimental_ndslice.html

On Tuesday, 22 March 2016 at 14:08:55 UTC, _d0s_ wrote:
>
> Idea2: Matrix Solvers
> Have some base algorithms to solve linear and quadtratic systems on top of those matrices. (LU, QR, ...)

You would be interested in
https://github.com/DlangScience

They have cblas for matrix multiplication and scid.linalg has an interface to LAPACK (the most common way to do LU/QR/etc). I don't have experience with these, but I think they were created before std.experimental.ndslice, so I'm not sure how well they inter-operate. I believe there is work being done on this, but I'm sure John Colvin et al would appreciate any help you would be able to provide.

With respect to your point about about sparse vs. dense matrix types and other special layouts, it would probably be possible to build some of that functionality on top of ndslice. I'd prefer there to be a focus of getting blas/LAPACK working seamlessly with ndslice before that.

On Tuesday, 22 March 2016 at 14:08:55 UTC, _d0s_ wrote:
> Idea3: Visualization
> Imho D is lacking a good UI toolkit. I again like here the simplicity of matlab that lets me just pop up a window, and show a simple diagram or picture. Often its not necessary to create a sophisticated UI, but having a visual representation of data often helps with debugging and understanding of algorithms.
>

If all you need are plotting tools, these would be useful
https://code.dlang.org/packages/ggplotd
https://code.dlang.org/packages/plotd

More complicated than that, I don't have familiarity with, but there are some other libraries worth looking at on https://code.dlang.org/

Idea 1:

Sigh I do wish the author of gl3n had given permission for relicense for Phobos. Would do what you want.

Idea 3:

My goal is get windowing/image library into Phobos. Now that is not a UI toolkit but you can atleast get a window up and show an image like a graph.
Kinda everything you want.

About web based UI's, just ew. They've been shown to not work time and time again. Nothing better than a native UI.

If you want to help me with windowing/image library, I need https://github.com/D-Programming-Language/phobos/pull/2845 to support blending.
Otherwise blah work being https://github.com/rikkimax/alphaPhobos/tree/master/source/std/experimental/bindings severely bigger.

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On Tuesday, 22 March 2016 at 15:19:10 UTC, rikki cattermole wrote:
> Idea 1:
>
> Sigh I do wish the author of gl3n had given permission for relicense for Phobos. Would do what you want.
>
> Idea 3:
>
> My goal is get windowing/image library into Phobos. Now that is not a UI toolkit but you can atleast get a window up and show an image like a graph.
> Kinda everything you want.

Any tips on how easy it will be to plot a cairo surface to a window? ggplotd currently relies on gtkd for that, but would be great if there is a D based solution.

I'm especially interested in plotting image of the below type in a window:

CAIRO_FORMAT_ARGB32[1]
each pixel is a 32-bit quantity, with alpha in the upper 8 bits, then red, then green, then blue. The 32-bit quantities are stored native-endian. Pre-multiplied alpha is used. (That is, 50% transparent red is 0x80800000, not 0x80ff0000.)

[1] cairographics.org/manual-1.2.0/cairo-Image-Surfaces.html

On Tuesday, 22 March 2016 at 15:33:04 UTC, Edwin van Leeuwen wrote:
> On Tuesday, 22 March 2016 at 15:19:10 UTC, rikki cattermole wrote:
>> Idea 1:
>>
>> Sigh I do wish the author of gl3n had given permission for relicense for Phobos. Would do what you want.
>>
>> Idea 3:
>>
>> My goal is get windowing/image library into Phobos. Now that is not a UI toolkit but you can atleast get a window up and show an image like a graph.
>> Kinda everything you want.
>
> Any tips on how easy it will be to plot a cairo surface to a window ?

Very easy.

- wrap a context in a Canvas with the methods for drawing.
- BLIT the cairo surface.

It also works with simple bitmaps, so image proceduraly rendered.
Actually I've started to work on this at the end of 2015.

(https://github.com/BBasile/kheops/blob/master/src/kheops/bitmap.d#L396)

While it was planned to make a native D UI, using it to plot 2D data would require very few work. There's also a OO wrapper called cairoD or something like that which is for sure very easy to use to render bitmap proceduraly.

The positive point with cairo is that it has a "png surfaces" so images can be saved in a single call (cairo_surface_write_to_png).

On Tuesday, 22 March 2016 at 15:50:15 UTC, Basile B. wrote:
> On Tuesday, 22 March 2016 at 15:33:04 UTC, Edwin van Leeuwen wrote:
>> On Tuesday, 22 March 2016 at 15:19:10 UTC, rikki cattermole wrote:
>>> Idea 1:
>>>
>>> Sigh I do wish the author of gl3n had given permission for relicense for Phobos. Would do what you want.
>>>
>>> Idea 3:
>>>
>>> My goal is get windowing/image library into Phobos. Now that is not a UI toolkit but you can atleast get a window up and show an image like a graph.
>>> Kinda everything you want.
>>
>> Any tips on how easy it will be to plot a cairo surface to a window ?
>
> Very easy.
>
> - wrap a context in a Canvas with the methods for drawing.
> - BLIT the cairo surface.

Thanks!

>
> It also works with simple bitmaps, so image proceduraly rendered.
> Actually I've started to work on this at the end of 2015.
>
> (https://github.com/BBasile/kheops/blob/master/src/kheops/bitmap.d#L396)

That looks interesting. Would you say kheops is stable enough to be relied upon  by other projects? Any plans to make it into a dub package?

Since kheops is vector based it would be even nicer to be able to convert a cairo svg/pdf surface to kheops.

> While it was planned to make a native D UI, using it to plot 2D data would require very few work. There's also a OO wrapper called cairoD or something like that which is for sure very easy to use to render bitmap proceduraly.

cairoD is indeed what ggplotd uses to produce the plot. And saving svg/png/pdf to disk is indeed very easy with cairo.

On Tuesday, 22 March 2016 at 16:01:43 UTC, Edwin van Leeuwen wrote:
> That looks interesting. Would you say kheops is stable enough to be relied upon  by other projects? Any plans to make it into a dub package?

No. This would require a bit of work (currently it's linux only).
Go with cairoD since it's already used for that.

thanks for all the opinions!

> Perhaps this is what you're looking for?
> https://dlang.org/phobos/std_experimental_ndslice.html

that would be a good starting point for a matrix library

> You would be interested in
> https://github.com/DlangScience

> They have cblas for matrix multiplication and scid.linalg has an interface to LAPACK (the > most common way to do LU/QR/etc). I don't have experience with these, but I think they were created before std.experimental.ndslice, so I'm not sure how well they inter-operate. I > believe there is work being done on this, but I'm sure John Colvin et al would appreciate > any help you would be able to provide.

thx, havent found that before :)
i haven't used lapack/blas before, i will have a look at it. i'm using mostly Eigen for my projects.

> If all you need are plotting tools, these would be useful
> https://code.dlang.org/packages/ggplotd
> https://code.dlang.org/packages/plotd
that would be somewhat close already to matlab like plotting

> Sigh I do wish the author of gl3n had given permission for relicense for Phobos. Would do what you want.

i have used gl3n before, it's not really what i'm looking for. gl3n afaik only provides up to 4x4 dense matrices, with the focus on being a GLM (http://glm.g-truc.net/0.9.7/index.html) replacement for the use with Opengl. correct me if i'm wrong.


Cairo and Kheops look interesting. I have used Openvg before. Some time ago i've created a little Openvg D wrapper for shiva vg ( https://code.dlang.org/packages/dopenvg ) . From a diagram or image viewer i'd also expect some level of interactivity. That's why i thought a web app with CEF would be suitable

do you have experience with creating web apps for desktop, or reasons why i'd definitively want to use a native framework for such a project? .. or for UI in general