I'd like to put down (draw with mouse...) an indeterminate numbers of points in a scene first, then, move these points on xyz.

I don't want to draw the points or shapes as if I would draw only ONE gridshape and would not clear the render, for example, 

but real elmts, all contro-able on xyz (with jit.expr later).

- The first solution I see is "reset, point xyz" to sketch 

but if I want to draw 400 autonomous points, I need 400 messages box or 400 messages in the same box or anything equivalent :(

..and I don't know how many points I'll draw :((

- The second solution is [jit.iter] to "position", like in many examples, but I think I would not have a good control on the flow ...

- A third one could be to use a float32 matrix with dims 20 20 for example, but how to progressively iterate it? 

- I didn't really already took my head on particles system in jitter (vishnu etc.). 

But is it possible to birth particules on demand?

I don't want to draw the points or shapes as if I would draw only ONE gridshape and would not clear the render, for example, 
but real elmts, all contro-able on xyz (with jit.expr later).

- The first solution I see is "reset, point xyz" to sketch 
but if I want to draw 400 autonomous points, I need 400 messages box or 400 messages in the same box or anything equivalent :(
..and I don't know how many points I'll draw :((

- A third one could be to use a float32 matrix  with dims 20 20 for example, but how to progressively iterate it? 
If I bang it, 400 elmts go out!

- I didn't really already took my head on particles system in jitter (vishnu etc.). 
But is it possible to birth particules on demand?

how-to

On Thu, Nov 13, 2008 at 11:43 PM, Derrick Giscloux

> I'd like to put down (draw with mouse...) an indeterminate numbers of

> points in a scene first, then, move these points on xyz.

> - A third one could be to use a float32 matrix with dims 20 20 for

> example, but how to progressively iterate it?

that's the best option, its will take some time to warp your head around it

but matix are the native format for mass manipulation of "lists" in jitter.

> - I didn't really already took my head on particles system in jitter

> But is it possible to birth particules on demand?

im still not sure what your after, better explain better, better better is

see this hack i did on the shatter recipe by Andrew, deconstructing that

recipe- for me- was key for matrix+opengl understanding

https://cycling74.com/forums/index.php?t=msg&goto=116508#msg_num_11

On Thu, Nov 13, 2008 at 11:43 PM, Derrick Giscloux
wrote:

>
> Hello,
>
>
> I'd like to put down (draw with mouse...) an indeterminate numbers of
> points in a scene first, then, move these points on xyz.

>
> - A third one could be to use a float32 matrix  with dims 20 20 for
> example, but how to progressively iterate it?
> If I bang it, 400 elmts go out!

that's the best option, its will take some time to warp your head around it
but matix are the native format for mass manipulation of "lists" in jitter.
400 elements are nothing.

>
> - I didn't really already took my head on particles system in jitter
> (vishnu etc.).
> But is it possible to birth particules on demand?

im still not sure what your after, better explain better, better better is
to post a patch

see this hack i did on the shatter recipe by Andrew, deconstructing that
recipe- for me- was key for matrix+opengl understanding

I can send all the cell to mesh, and make quads but it is one stack of cells.

Yes! thanks Yair!
I worked on this, since now

How to have cell appear after cell ... ?


On Sat, Nov 15, 2008 at 2:38 AM, Derrick Giscloux

its hard to understand your goal, cant help further

> I can send all the cell to mesh, and make quads but it is one stack of

> How to have cell appear after cell ... ?

On Sat, Nov 15, 2008 at 2:38 AM, Derrick Giscloux
wrote:

>
> Yes! thanks Yair!
> I worked on this, since now
>
> But what about iterate a matrix?
>
its hard to understand your goal, cant help further
im on max 4.6 btw

>
> I can send all the cell to mesh, and make quads but it is one stack of
> cells.
>
> How to have cell appear after cell ... ?
>

I want to some drawing in jitter, via [jit.window]->[route mouse].

But rather than (for example) don't clear the render and keep trails of an object, I want the mouse to put points (ex: w/mesh).

Further I'd like to apply forces to these points.

Is there a way to do that (put individual points) ?

First of all, I think you're correct in your assumption that handling 

all the data *outside the matrix* would be difficult. 400 elements 

Do as much as possible inside a matrix, and only "spill" it if need be.

So, for instance (and this is just one way of doing things - probably 

Mouse input -> setcell in jit.matrix, where x/y/z and other parameters 

Then you can choose to either apply jit.op or similar to the *entire* 

matrix, or apply a gradient to that processing, giving you a gradual 

Another way would indeed be to iterate through it, each new step with a 

new degree of processing - the heavy part, computationally, would be 

extracting this data and then reintroducing them to a new matrix (or the 

Much better to stay in the matrix. And yes, 20x20 cells is NOTHING. :)

First of all, I think you're correct in your assumption that handling 
all the data *outside the matrix* would be difficult. 400 elements 
processed iteratively can be difficult.

So, for instance (and this is just one way of doing things - probably 
not the optimal one!):

Mouse input -> setcell in jit.matrix, where x/y/z and other parameters 
get stored, four params per cell.
Then you can choose to either apply jit.op or similar to the *entire* 
matrix, or apply a gradient to that processing, giving you a gradual 
implementation of the operation.
Another way would indeed be to iterate through it, each new step with a 
new degree of processing - the heavy part, computationally, would be 
extracting this data and then reintroducing them to a new matrix (or the 
same, in a feedback loop).

Much better to stay in the matrix. And yes, 20x20 cells is NOTHING.  :)

I don't want to draw the points or shapes as if I would draw only ONE gridshape and would not clear the render, for example,

As far as the "clear" goes, you can also use the "clear" command to jit.gl.render, but use an erase_color with a very low alpha (like erase_color 0. 0. 0. 0.001). This will take a long time to clear out what's there, so you'll get long trails of your points etc. Using a low alpha for your points will also allow lots more drawing before you get a screen full of opaque points.

20X20 is definitely a small matrix :) but don't be afraid of using something like [uzi] either, to draw your points, if it works better. However, all the jit.ops available will probably work best for you.

Whatever you draw into a jit.gl.sketch can then be stretched, rotated, etc. as a group.

-->
I don't want to draw the points or shapes as if I would draw only ONE gridshape and would not clear the render, for example,
but real elmts, all contro-able on xyz (with jit.expr later).
-->

20X20 is definitely a small matrix  :)  but don't be afraid of using something like [uzi] either, to draw your points, if it works better. However, all the jit.ops available will probably work best for you.

Whatever you draw into a jit.gl.sketch can then be stretched, rotated, etc. as a group.


> Whatever you draw into a jit.gl.sketch can then be stretched, rotated, etc. as a group

Just use a [scale float float float] to the jit.gl.sketch, as you can with most GL objects. Also there's position, rotatexyz, etc. Until you "reset" the jit.gl.sketch, it'll remember everything on there and you can transform it however you want (at least that's my understanding).

Try out this example patch, hopefully is self-explanatory. Simple, yet still fun to mess with :)

Sorry only Max 5, screenshot attached to see what's going on if you're on 4.

Try out this example patch, hopefully is self-explanatory. Simple, yet still fun to mess with :) 

As far as the "clear" goes, you can also use the "clear" command to jit.gl.render

My mistake, I meant "erase", using the different alpha values for erase_color.

-->
As far as the "clear" goes, you can also use the "clear" command to jit.gl.render
-->

My mistake, I meant "erase", using the different alpha values for erase_color.


I wonder why there is nothing about "beginstroke" in jitter Object Reference.

Some on the sketch commands would be hidden? or I have to read the Open GL books?

Thanks for the screenshot seejayjames.
So it just works like any other gl'

This object seems huge.
Where to start for specifics?

How to ...