Cycling 74 » Topic: corner pin adjustement of plane/quad with videotexture? http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/feed Wed, 19 Jun 2013 01:47:15 +0000 http://bbpress.org/?v=2.2.4 http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-41839 <![CDATA[corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-41839 Mon, 19 Jan 2009 16:36:36 +0000 hc gilje Before I twist my brain yet another turn:

I am trying to achieve something which seems simple in environments like quartz composer/vdmx and vvvv: corner pin positioning of a quad/plane.

If you take a look at this link there is an example video and also the shader used to create the warp for qc/vdmx: http://www.memo.tv/projection_mapping_quad_warping_with_quartz_composer_vdmx

In vvvv there is the homography module which does the same thing.

I have looked at different keystone examples on the list (particularly jasch and robtherich), but they seem quite complex to achieve a simple corner pinning (and also I would want many instances in my setup).

I have figured out how to capture parts of or the whole gl scene to a texture, and then ideally I would want a shader based on the code from the link above:

uniform vec2 BL, BR, TL, TR;
uniform vec2 renderSize;

void main() {
// transform from QC object coords to 0…1
vec2 p = (vec2(gl_Vertex.x, gl_Vertex.y) + 1.) * 0.5;

// interpolate bottom edge x coordinate
vec2 x1 = mix(BL, BR, p.x);

// interpolate top edge x coordinate
vec2 x2 = mix(TL, TR, p.x);

// interpolate y position
p = mix(x1, x2, p.y);

// transform from 0…1 to QC screen coords
p = (p – 0.5) * renderSize;

gl_Position = gl_ModelViewProjectionMatrix * vec4(p, 0, 1);
gl_FrontColor = gl_Color;
gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;
}

I have so far not been able to get this shader code to work in jitter, I haven

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149189 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149189 Mon, 19 Jan 2009 17:04:29 +0000 Joshua Kit Clayton On Jan 19, 2009, at 8:36 AM, hc gilje wrote:

> I am trying to achieve something which seems simple in environments
> like quartz composer/vdmx and vvvv: corner pin positioning of a quad/
> plane.

Something like the following email coding should be all you need. You
might need to flip the texture coordinates to get the proper texture
orientation. Check out the redbook if the following doesn’t make sense.

glbindtexture texname,
glbegin quads,
gltexcoord 0 0,
glvertex left top 0,
gltexcoord 1 0,
glvertex right top 0,
gltexcoord 1 1,
glvertex right bottom 0,
gltexcoord 0 1,
glvertex left bottom 0,
glend

-Joshua

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149190 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149190 Mon, 19 Jan 2009 21:18:17 +0000 hc gilje here is a simple patch with a quad using a video texture, but the texture gets a pretty nasty distortion even with moderate tweaks of the quad, so I need to do something with the texture coordinates as well I assume?

hc

– Pasted Max Patch, click to expand. –

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149191 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149191 Mon, 19 Jan 2009 21:57:26 +0000 Joshua Kit Clayton On Jan 19, 2009, at 1:18 PM, hc gilje wrote:

>
> here is a simple patch with a quad using a video texture, but the
> texture gets a pretty nasty distortion even with moderate tweaks of
> the quad, so I need to do something with the texture coordinates as
> well I assume?

Sorry about that. Yeah, you’ll be better off using either a more dense
vertex mesh, since a simple quad breaks down into two triangles and
interpolates only within each triangle.

The basic idea would be to make a 4 cell matrix containing each of
your corner xyz values, and the standard texture coordinates, and then
send it to a 20×20 or whatever jit.matrix @interp 1. This will make a
mesh which can be sent on to jit.gl.mesh, jit.gl.sketch drawmatrix, or
jit.gl.render or whatever your preferred means of drawing vertex data
as a trigrid/quadgrid. The more vertices in your mesh the better it
should look.

-Joshua

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149192 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149192 Mon, 19 Jan 2009 22:18:23 +0000 hc gilje I was sort of guessing that was the problem, but that still makes me wonder why such a simple shader as the one I linked to for quartz composer doesn

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149193 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149193 Mon, 19 Jan 2009 22:34:50 +0000 Joshua Kit Clayton

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149194 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149194 Mon, 19 Jan 2009 22:50:35 +0000 Joshua Kit Clayton Here’s what I’m suggesting. Took about 10 minutes to make from your
existing patch.

– Pasted Max Patch, click to expand. –

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149195 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149195 Mon, 19 Jan 2009 22:52:05 +0000 hc gilje ok, I am not obsessed with shaders myself,
I just look at the output and see no unwanted distortion in the video texture in the qc example, and lots of distortion with my jitter test.
So obviously I am missing something?

hc

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149196 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149196 Mon, 19 Jan 2009 22:55:51 +0000 hc gilje that was quick, thanks!
I would have spent a bit more than 10 minutes on that :-)

So if get rid of the aliasing I will be happy, and maybe I will force myself to make a shader out of it. Maybe that

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149197 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149197 Mon, 19 Jan 2009 23:08:21 +0000 Joshua Kit Clayton On Jan 19, 2009, at 2:55 PM, hc gilje wrote:

> So if get rid of the aliasing I will be happy

Here you go with a natively sized jit.gl.texture object and @fsaa 1.
That’s as good as you’ll get without some alternate form of texture
filtering. Bilinear filtering (which is most likely the same as is
used in QC/vvvv), will have visible aliasing artifacts when
downsampling by large amounts. Performing gaussian/bicubic/mitchell/
etc filtering is more of an endeavor.

-Joshua

– Pasted Max Patch, click to expand. –

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149198 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149198 Mon, 19 Jan 2009 23:16:34 +0000 hc gilje thanks,
yes it looks quite good here. I didn

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149199 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149199 Mon, 19 Jan 2009 23:16:44 +0000 Joshua Kit Clayton On Jan 19, 2009, at 2:52 PM, hc gilje wrote:

> I just look at the output and see no unwanted distortion in the
> video texture in the qc example, and lots of distortion with my
> jitter test.

Texture size? Use jit.qt.movie @adapt 1-> jit.gl.texture to make sure
that’s not the issue.

Dimensions of the plane’s vertex mesh? Try 40×40 rather than 20×20.

I’m pretty sure it’s only one of those two possibilities. In your
first example you were using a 320×240 -> 256×256 down sampling
without any antialiasing, which of course would have significant
artifacts.

-Joshua

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149200 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149200 Mon, 19 Jan 2009 23:30:44 +0000 hc gilje your patch came while I was writing my post, so that is why my message about texture distortion appears after your example, sorry for the confusion.
it works beautifully with 20×20 here.
thanks again!

hc

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149201 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149201 Mon, 19 Jan 2009 23:36:14 +0000 Joshua Kit Clayton On Jan 19, 2009, at 3:16 PM, hc gilje wrote:

> I am just wondering if this approach would work if I wanted to
> apply different warpings to different videoplanes. Since the matrix
> transform goes directly to the renderer in this example, I would
> need some way to connect individual matrix transforms to each
> separate plane.
> This is where I thought it would be handy to have a shader version,
> but would it work with your method if things are banged in the right
> order?

Sure. You can also use jit.gl.mesh if it makes your patch organization
simpler… So many different ways to do the same thing.

-Joshua

– Pasted Max Patch, click to expand. –

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149202 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149202 Mon, 19 Jan 2009 23:50:38 +0000 hc gilje excellent, thanks for sharing!
I have had quite a few false starts trying to get this working, so glad you took the time to help me out. This should be useful for a few others than me as well.

hc

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149203 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149203 Mon, 19 Jan 2009 23:56:08 +0000 Scott Fitzgerald I am one of those few others, was going to be asking a similar
question in a few days if I couldn’t get it right.

Thanks to you both!

~s

On Mon, Jan 19, 2009 at 6:50 PM, hc gilje wrote:
>
> excellent, thanks for sharing!
> I have had quite a few false starts trying to get this working, so glad you took the time to help me out. This should be useful for a few others than me as well.
>
> hc

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149204 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149204 Tue, 20 Jan 2009 12:33:57 +0000 hc gilje Here is a modified version of the patch, now easy to use as a fullscreen keystone tool.
By clicking directly on the output screen, you can easily place/displace the image by corner pinning.

hc

– Pasted Max Patch, click to expand. –

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149205 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149205 Tue, 20 Jan 2009 12:57:03 +0000 FP hi,

just by curiosity.
how to just crop with your solution ?
and keep the possibility to choose between “crop” and “adapt”.

thx.
f./

i had it by this way :

– Pasted Max Patch, click to expand. –

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149206 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149206 Tue, 20 Jan 2009 15:36:49 +0000 hc gilje I haven

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149207 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149207 Tue, 20 Jan 2009 23:14:50 +0000 pelado This makes the texture part a bit more efficient. You can send messages to
the slabs to change the dimensions of their texture units if you need to.

– Pasted Max Patch, click to expand. –

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149208 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149208 Wed, 02 Jun 2010 02:32:41 +0000 e-ars I am new with max/msp, and not where paste the key patcher, tell me please

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149209 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149209 Tue, 02 Nov 2010 16:49:06 +0000 outoff hi, joshua! nice tip with 4 cell matrix!
but I try to add 5th control point in center without success (
matrix must be 3×3 now?

humbala ! ;-)

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149210 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149210 Fri, 18 Mar 2011 03:19:00 +0000 joshua goldberg

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149211 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149211 Fri, 18 Mar 2011 03:19:50 +0000 joshua goldberg someone sent me another version of this patch, looking to make it flexible in terms of vertex points. i moved it to javascript.

– Pasted Max Patch, click to expand. –

and this is the keygen.js javascript:

// keygen.js
// joshua goldberg 2011
// defines control points for keystoning video

// initialization code

autowatch = 1; // why would you NOT use this
inlets = 1;
outlets = 1;
// X_WIDTH for 4:3= 1.33333. for 16:9= 1.777777
var X_WIDTH=1.333333;
var totalWidth = X_WIDTH * 2.0; // full GL width of image
var mySize=[3,3]; // size of ctlmatrix as global (dummy values)
// we put dummy values in ctlMatrix to make sure it’s globally available
var ctlMatrix = new JitterMatrix(5, “float32″, mySize[0], mySize[1]);
// and the name of the control matrix is also a global
var myName = ctlMatrix.name;
sizer(2,2); //preloads 2×2 values for placement
post(“keygen.js reloaded!n”); // so i know it’s been properly compiled

// functions

function sizer(x,y){
mySize=[x,y];
var sliceSize = totalWidth/(x-1) // size of each quantized Xslice
// this is the cell placement init code
// first redefine ctlMatrix with the proper size
ctlMatrix.dim = [x, y];
for (i=0; i

]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149212 <![CDATA[Re: corner pin adjustement of plane/quad with videotexture?]]> http://cycling74.com/forums/topic/corner-pin-adjustement-of-planequad-with-videotexture/#post-149212 Fri, 18 Mar 2011 03:19:54 +0000 joshua goldberg someone sent me another version of this patch, looking to make it flexible in terms of vertex points. i moved it to javascript.

– Pasted Max Patch, click to expand. –

and this is the keygen.js javascript:

// keygen.js
// joshua goldberg 2011
// defines control points for keystoning video

// initialization code

autowatch = 1; // why would you NOT use this
inlets = 1;
outlets = 1;
// X_WIDTH for 4:3= 1.33333. for 16:9= 1.777777
var X_WIDTH=1.333333;
var totalWidth = X_WIDTH * 2.0; // full GL width of image
var mySize=[3,3]; // size of ctlmatrix as global (dummy values)
// we put dummy values in ctlMatrix to make sure it's globally available
var ctlMatrix = new JitterMatrix(5, “float32″, mySize[0], mySize[1]);
// and the name of the control matrix is also a global
var myName = ctlMatrix.name;
sizer(2,2); //preloads 2×2 values for placement
post(“keygen.js reloaded!n”); // so i know it's been properly compiled

// functions

function sizer(x,y){
mySize=[x,y];
var sliceSize = totalWidth/(x-1) // size of each quantized Xslice
// this is the cell placement init code
// first redefine ctlMatrix with the proper size
ctlMatrix.dim = [x, y];
for (i=0; i

]]>