Hi Pete, Sorry I forgot to send that example as reference, but what you have so far is good.
I think there's just a couple of things you should need to change to get this working. 1- Don't normalize the "from" and "to" coordinates. The matrices you're building need to map from the "to" corners to a unit square, and then from a unit square to your from coordinates, using absolute values. So just do: to1x = theCornerpinNode['to1'].value()[0] etc... 2- By the time you fill the "theCornerpinAsMatrix" object, you should have the correct transformation matrix already, but in column-major order. Unfortunately, values in matrix knobs seem to be returned (or set when using setValue) in row-major order, so you would either need to fill in the matrix knob in a loop mirroring the cell values, or, what I usually do is transpose the matrix before filling in the knob. So, in your script, after this line: theCornerpinAsMatrix = projectionMatrixTo * projectionMatrixFrom.inverse() You can just do: theCornerpinAsMatrix.transpose() And then continue as you were. See if that helps. Cheers, Ivan On Mon, Aug 22, 2011 at 6:37 PM, Pete O'Connell <[email protected]>wrote: > #OK I think I'm getting close. I tried Ivan's instructions but I think I > missed something. It looks really close though. Anyone care to take a look > at what I have so far? > > ############################################################################################################################## > projectionMatrixTo = nuke.math.Matrix4() > projectionMatrixFrom = nuke.math.Matrix4() > > #dir(projectionMatrix) > theCornerpinNode = nuke.toNode("CornerPin2D1") > imageWidth = float(theCornerpinNode.width()) > imageHeight = float(theCornerpinNode.height()) > > #normalized to and from coordinates > to1x = theCornerpinNode['to1'].value()[0]/imageWidth > to1y = theCornerpinNode['to1'].value()[1]/imageHeight > to2x = theCornerpinNode['to2'].value()[0]/imageWidth > to2y = theCornerpinNode['to2'].value()[1]/imageHeight > to3x = theCornerpinNode['to3'].value()[0]/imageWidth > to3y = theCornerpinNode['to3'].value()[1]/imageHeight > to4x = theCornerpinNode['to4'].value()[0]/imageWidth > to4y = theCornerpinNode['to4'].value()[1]/imageHeight > > from1x = theCornerpinNode['from1'].value()[0]/imageWidth > from1y = theCornerpinNode['from1'].value()[1]/imageHeight > from2x = theCornerpinNode['from2'].value()[0]/imageWidth > from2y = theCornerpinNode['from2'].value()[1]/imageHeight > from3x = theCornerpinNode['from3'].value()[0]/imageWidth > from3y = theCornerpinNode['from3'].value()[1]/imageHeight > from4x = theCornerpinNode['from4'].value()[0]/imageWidth > from4y = theCornerpinNode['from4'].value()[1]/imageHeight > > > > projectionMatrixTo.mapUnitSquareToQuad(to1x,to1y,to2x,to2y,to3x,to3y,to4x,to4y) > > projectionMatrixFrom.mapUnitSquareToQuad(from1x,from1y,from2x,from2y,from3x,from3y,from4x,from4y) > > theCornerpinAsMatrix = projectionMatrixTo*projectionMatrixFrom.inverse() > > theNewCornerpinNode = nuke.toNode("CornerPin2D2") > theNewCornerpinNode['transform_matrix'].setValue(theCornerpinAsMatrix) > > > ############################################################################################################################ > #Thanks > #Pete > > > On Tue, Aug 23, 2011 at 10:14 AM, Pete O'Connell > <[email protected]>wrote: > >> Hi Michael. I had a look at the planar tracker but as far as I can tell, >> that node creates a cornerpin based on the matrix that it calculates, but as >> far as I can see there is no way in that you can feed the planar tracker >> cornerpin data and have it calculate the corresponding Matrix. I think >> nuke.math.Matrix4 is the way. >> >> Pete >> >> >> On Tue, Aug 23, 2011 at 3:30 AM, Michael Garrett >> <[email protected]>wrote: >> >>> I haven't got 6.3 in front of me but does the PlanarTracker add anything >>> into the mix to make this easier? I seem to remember it outputs a 4*4 >>> matrix for the planar track which is essentially a corner pin but I'll admit >>> I need to look more closely at it. >>> >>> >>> On 21 August 2011 23:40, Pete O'Connell <[email protected]> wrote: >>> >>>> Thanks a lot Ivan. I'll have a play around with that tonight. >>>> >>>> Cheers >>>> Pete >>>> >>>> >>>> On Mon, Aug 22, 2011 at 3:57 PM, Ivan Busquets >>>> <[email protected]>wrote: >>>> >>>>> Hi Pete, >>>>> >>>>> It's very possible, but probably easier to do it in Python than using >>>>> expression-links. Have a look at the nuke.math.Matrix4 class, and its >>>>> mapUnitSquareToQuad() method. >>>>> >>>>> I have a function somewhere to feed the transformation of a CornerPin >>>>> node into the "matrix" knob of a roto/rotopaint node that would >>>>> probably fit the bill for this too. I can try to dig that up if you're >>>>> interested, but it would roughly consist of the following steps: >>>>> >>>>> 1 - Get the coordinates of the 4 "TO" corners from your cornerpin node. >>>>> 2 - Build a "TO" matrix using mapUnitSquareToQuad(to0.x, to0.y, to1.x, >>>>> to1.y, ...) >>>>> 3 - Get the coordinates of the 4 "FROM" corners from your cornerpin >>>>> node. >>>>> 4 - Build a "FROM" matrix using mapUnitSquareToQuad(from0.x, from0.y, >>>>> from1.x, from1.y, ...) >>>>> 5 - The final transformation matrix should be => to_matrix * >>>>> from_matrix.inverse(). >>>>> >>>>> Then you can use that to fill in the matrix knob in a gridwarp, a roto >>>>> node, etc. >>>>> >>>>> Not the best example, but if you want some more info on how to use >>>>> nuke.math.Matrix4.mapUnitSquareToQuad(), have a look here (towards the >>>>> end of the page). >>>>> >>>>> >>>>> http://www.nukepedia.com/written-tutorials/using-the-nukemath-python-module-to-do-vector-and-matrix-operations/page-4/ >>>>> >>>>> Hope that helps. >>>>> >>>>> Cheers, >>>>> Ivan >>>>> >>>>> On Sun, Aug 21, 2011 at 10:24 PM, Pete O'Connell >>>>> <[email protected]> wrote: >>>>> > Hi does anyone know if it is possible somehow to convert cornerpin >>>>> values to >>>>> > a 4 by 4 matrix? Seem like it would be useful for the new Gridwarp >>>>> and >>>>> > Splinewarp nodes. >>>>> > Thanks >>>>> > Pete >>>>> > >>>>> > >>>>> > _______________________________________________ >>>>> > Nuke-users mailing list >>>>> > [email protected], http://forums.thefoundry.co.uk/ >>>>> > http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >>>>> > >>>>> _______________________________________________ >>>>> Nuke-users mailing list >>>>> [email protected], http://forums.thefoundry.co.uk/ >>>>> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >>>>> >>>> >>>> >>>> >>>> -- >>>> Pete >>>> >>>> _______________________________________________ >>>> Nuke-users mailing list >>>> [email protected], http://forums.thefoundry.co.uk/ >>>> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >>>> >>> >>> >>> _______________________________________________ >>> Nuke-users mailing list >>> [email protected], http://forums.thefoundry.co.uk/ >>> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >>> >> >> >> >> -- >> Pete >> > > > > -- > Pete > > _______________________________________________ > Nuke-users mailing list > [email protected], http://forums.thefoundry.co.uk/ > http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >
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