Elisp: Generating Image Files

Elisp: Generating Image Files

[Christopher Howard]

Hi, is there a library for Emacs that would allow me to use elisp to
generate an image file? E.g. a function that takes an array of RBGA
color values and outputs a PNG file?

-- 
https://qlfiles.net

Re: Elisp: Generating Image Files

[Emanuel Berg]

Christopher Howard wrote:

> Hi, is there a library for Emacs that would
> allow me to use elisp to generate an image
> file? E.g. a function that takes an array of
> RBGA color values and outputs a PNG file?

There is a chapter in the Elisp manual which
might help you, namely "Defining Images":

    http://www.gnu.org/software/emacs/manual/html_node/elisp/Defining-Images.html

Also check out the parent section, "Images"!

-- 
underground experts united
http://user.it.uu.se/~embe8573

Re: Elisp: Generating Image Files

[Christopher Howard]

But that chapter are only about loading and display images, as far as I
can tell. I want to generate the image itself.

On 05/20/2017 06:37 AM, Emanuel Berg wrote:
> Christopher Howard wrote:
> 
>> Hi, is there a library for Emacs that would
>> allow me to use elisp to generate an image
>> file? E.g. a function that takes an array of
>> RBGA color values and outputs a PNG file?
> 
> There is a chapter in the Elisp manual which
> might help you, namely "Defining Images":
> 
>     http://www.gnu.org/software/emacs/manual/html_node/elisp/Defining-Images.html
> 
> Also check out the parent section, "Images"!
> 

-- 
https://qlfiles.net

Re: Elisp: Generating Image Files

[Yuri Khan]

On Sat, May 20, 2017 at 10:35 PM, Christopher Howard
<christopher.howard@qlfiles.net> wrote:
> But that chapter are only about loading and display images, as far as I
> can tell. I want to generate the image itself.

What larger goal do you want to achieve by generating an image?

The master branch contains a library named svg.el. You might be able
to use it, or just generate SVG text with a bunch of (insert)s.

Re: Elisp: Generating Image Files

[Christopher Howard]

I see Emacs depends on libpng, which I believe has writing
functionality. Is there some way to interface with that through elisp?

On 05/20/2017 03:58 PM, Christopher Howard wrote:
> Hi. One of my little hobbies is exploring digital art or patterns
> generated with various algorithms and formulas. E.g.:
> 
> https://qlfiles.net/the-ql-files/next-nearest-neighbors-cellular-automata/
> https://qlfiles.net/the-ql-files/interference-patterns/
> 
> Of course, there's a lot of different areas to explore, and some of them
> involve the need to be able output the pixels in pixmap images.
> 
> On 05/20/2017 12:33 PM, Yuri Khan wrote:
>> On Sat, May 20, 2017 at 10:35 PM, Christopher Howard
>> <christopher.howard@qlfiles.net> wrote:
>>> But that chapter are only about loading and display images, as far as I
>>> can tell. I want to generate the image itself.
>>
>> What larger goal do you want to achieve by generating an image?
>>
>> The master branch contains a library named svg.el. You might be able
>> to use it, or just generate SVG text with a bunch of (insert)s.
>>
> 

-- 
https://qlfiles.net

Re: Elisp: Generating Image Files

[Thien-Thi Nguyen]

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() Christopher Howard <christopher.howard@qlfiles.net>
() Fri, 19 May 2017 21:20:01 -0800

   Hi, is there a library for Emacs that would allow me to use
   elisp to generate an image file? E.g. a function that takes
   an array of RBGA color values and outputs a PNG file?

I (wrote and) use xpm.el (et al):

 http://www.gnuvola.org/software/xpm/

You can generate XPM and convert to PNG (or any other format).
In the source repo, see flower.el for an example program (that
shows the Code Enhancement Opportunity that lies ahead.  :-D).

-- 
Thien-Thi Nguyen -----------------------------------------------
 (defun responsep (query)
   (pcase (context query)
     (`(technical ,ml) (correctp ml))
     ...))                              748E A0E8 1CB8 A748 9BFA
--------------------------------------- 6CE4 6703 2224 4C80 7502


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Re: Elisp: Generating Image Files

[Emanuel Berg]

Thien-Thi Nguyen wrote:

> Code Enhancement Opportunity

I always wondered what CEO actually meant - and
this is surely a surprise, as those guys never
seemed to know anything about code!

-- 
underground experts united
http://user.it.uu.se/~embe8573

Re: Elisp: Generating Image Files

[tomas]

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On Fri, May 26, 2017 at 02:42:25PM +0200, Emanuel Berg wrote:
> Thien-Thi Nguyen wrote:
> 
> > Code Enhancement Opportunity
> 
> I always wondered what CEO actually meant - and
> this is surely a surprise, as those guys never
> seemed to know anything about code!

When there's nothing, the enhancement opportunities are maximal
(assuming a non-negative domain).

Cheers
- -- t
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Re: Elisp: Generating Image Files

[Emanuel Berg]

>>> Code Enhancement Opportunity
>>
>> I always wondered what CEO actually meant -
>> and this is surely a surprise, as those guys
>> never seemed to know anything about code!
>
> When there's nothing, the enhancement
> opportunities are maximal (assuming
> a non-negative domain).

So where does that leave us after X years'
doing this? Answer: what is left is either too
difficult, or it is too big an effort to do.

After climbing Annapurna, some people feel
enriched their entire life. While others feel
cheated of their grail, knowing no coming
adventure or conquest will ever match it...

*sob*

-- 
underground experts united
http://user.it.uu.se/~embe8573